text:
|Publication number
|Publication type
|Application number
|Publication date
|25 Feb 2003
|Filing date
|10 Oct 2001
|Priority date
|16 Oct 2000
|Fee status
|Also published as
|Publication number
|Gordon Cheng I. Chen, Gary Peter Richardson
|Original Assignee
|Ciba Specialty Chemicals Water Treatments Ltd.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (28), Non-Patent Citations (3), Referenced by (53), Classifications (19), Legal Events (4)
|External Links: USPTO, USPTO Assignment, Espacenet
This application claims benefit of U.S. Provisioned Application No. 60/240,635 filed Oct. 16, 2000.
This invention relates to processes of making paper and paperboard from a cellulosic stock, employing a novel flocculating system.
During the manufacture of paper and paper board a cellulosic thin stock is drained on a moving screen (often referred to as a machine wire) to form a sheet which is then dried. It is well known to apply water soluble polymers to the cellulosic suspension in order to effect flocculation of the cellulosic solids and enhance drainage on the moving screen.
In order to increase output of paper many modern paper making machines operate at higher speeds. As a consequence of increased machine speeds a great deal of emphasis has been placed on drainage and retention systems that provide increased drainage. However, it is known that increasing the molecular weight of a polymeric retention aid which is added immediately prior to drainage will tend to increase the rate of drainage but damage formation. It is difficult to obtain the optimum balance of retention, drainage, drying and formation by adding a single polymeric retention aid and it is therefore common practice to add two separate materials in sequence.
EP-A-235893 provides a process wherein a water soluble substantially linear cationic polymer is applied to the paper making stock prior to a shear stage and then reflocculating by introducing bentonite after that shear stage. This process provides enhanced drainage and also good formation and retention. This process which is commercialised by Ciba Specialty Chemicals under the Hydrocol� trade mark has proved successful for more than a decade.
More recently there have been various attempts to provide variations on this theme by making minor modifications to one or more of the components.
U.S. Pat. No. 5,393,381 describes a process in which a process of making paper or board by adding a water soluble branched cationic polyacrylamide and a bentonite to the fibrous suspension of pulp. The branched cationic polyacrylamide is prepared by polymerising a mixture of acrylamide, cationic monomer, branching agent and chain transfer agent by solution polymerisation.
U.S. Pat. No. 5,882,525 describes a process in which a cationic branched water soluble polymer with a solubility quotient greater than about 30% is applied to a dispersion of suspended solids, e.g. a paper making stock, in order to release water. The cationic branched water soluble polymer is prepared from similar ingredients to U.S. Pat. No. 5,393,381 i.e. by polymerising a mixture of acrylamide, cationic monomer, branching agent and chain transfer agent.
In WO-A-9829604 a process of making paper is described in which a cationic polymeric retention aid is added to a cellulosic suspension to form flocs, mechanically degrading the flocs and then reflocculating the suspension by adding a solution of a second anionic polymeric retention aid. The anionic polymeric retention aid is a branched polymer which is characterised by having a rheological oscillation value of tan delta at 0.005 Hz of above 0.7 or by having a deionised SLV viscosity number which is at least three times the salted SLV viscosity number of the corresponding polymer made in the absence of branching agent. The process provided significant improvements in the combination of retention and formation by comparison to the earlier prior art processes.
EP-A-308752 describes a method of making paper in which a low molecular weight cationic organic polymer is added to the furnish and then a colloidal silica and a high molecular weight charged acrylamide copolymer of molecular weight at least 500,000. The description of the high molecular weight polymers indicates that they are linear polymers.
EP-A-462365 describes a method of making paper which comprises adding to an aqueous paper furnish ionic, organic microparticles which have an unswollen particle diameter of less than 750 nanometers if cross-linked and less than 60 nanometers if non-cross-linked and water-insoluble and have an anionicity of at least 1%, but at least 5% if cross-linked, anionic and used as the sole retention additive. The process is said to result in significant increase in fibre retention and improvements in drainage and formation.
EP-484617 describes a composition comprising cross-linked anionic or amphoteric, organic polymeric microparticles, said microparticles having an unswollen number average particle size diameter of less than 0.75 microns, a solution viscosity of at least 1.1 mPa.s and a cross-linking agent content of above 4 molar parts per million, based on the monomeric units and an ionicity of at least 5.0%. The polymers are described as being useful for a wide range of solid-liquid separation operations and specifically said to increase the drainage rates paper making.
However, there still exists a need to further enhance paper making processes by further improving drainage, retention and formation. Furthermore there also exists the need for providing a more effective flocculation system for making highly filled paper.
FIG. 1 is a graph retention versus dosage for various systems.
FIG. 2 is a graph showing ash retention versus dosage for various systems.
FIG. 3 is a graph showing drainage versus dosage for various systems.
According to the present invention a process is provided for making paper or paper board comprising forming a cellulosic suspension, flocculating the suspension, draining the suspension on a screen to form a sheet and then drying the sheet, characterised in that the suspension is flocculated using a flocculation system comprising a siliceous material and organic microparticles which have an unswollen particle diameter of less than 750 nanometers.
The microparticles may be prepared according to any suitable technique documented in the literature. They may be prepared from a monomer blend that comprises water soluble ethylenically unsaturated monomers and polymerised by any suitable polymerisation technique that provides microparticles which have an unswollen particle diameter of less than 750 nanometers. The monomer blend may also comprise cross-linking agent. Generally the amount of crosslinking agent may be any suitable amount, for instance up to 50,000 ppm on a molar basis. Typically the amounts of cross-linking agent are in the range 1 to 5,000 ppm.
The microparticles may be prepared in accordance with the teachings of EP-A-484617. Desirably the microparticles exhibit a solution viscosity of at least 1.1 mPa.s and a cross-linking agent content of above 4 molar ppm based on monomeric units. Preferably the microparticles have an ionicity of at least 5.0% More preferably the microparticles are anionic.
In one form of the invention the microparticles are microbeads prepared in accordance with EP462365. The microbeads have a particle size of less than 750 nanometers if cross-linked and less than 60 nanometers if non-cross-linked and water-insoluble.
Preferably the microparticles exhibit a rheological oscillation value of tan delta at 0.005 Hz of below 0.7 based on 1.5% by weight polymer concentration in water. More preferably the tan delta value is below 0.5 and usually in the range 0.1 to 0.3.
It has surprisingly been found that flocculating the cellulosic suspension using a flocculation system that comprises a siliceous material and organic polymeric microparticles provides improvements in retention, drainage and formation by comparison to a system using the polymeric microparticles alone or the siliceous material in the absence of the polymeric microparticles.
The siliceous material may be any of the materials selected from the group consisting of silica based particles, silica microgels, colloidal silica, silica sols, silica gels, polysilicates, aluminosilicates, polyaluminosilicates, borosilicates, polyborosilicates, zeolites or swellable clay.
This siliceous material may be in the form of an anionic microparticulate material. Alternatively the siliceous material may be a cationic silica. Desirably the siliceous material may be selected from silicas and polysilicates. The silica may be for example any colloidal silica, for instance as described in WO-A-8600100. The polysilicate may be a colloidal silicic acid as described in U.S. Pat. No. 4,388,150.
The polysilicates of the invention may be prepared by acidifying an aqueous solution of an alkali metal silicate. For instance polysilicic microgels otherwise known as active silica may be prepared by partial acidification of alkali metal silicate to about pH 8-9 by use of mineral acids or acid exchange resins, acid salts and acid gases. It may be desired to age the freshly formed polysilicic acid in order to allow sufficient three dimensional network structure to form. Generally the time of ageing is insufficient for the polysilicic acid to gel. Particularly preferred siliceous material include polyalumino-silicates. The polyaluminosilicates may be for instance aluminated polysilicic acid, made by first forming polysilicic acid microparticles and then post treating with aluminium salts, for instance as described in U.S. Pat. No. 5,176,891. Such polyaluminosilicates consist of silicic microparticles with the aluminium located preferentially at the surface.
Alternatively the polyaluminosilicates may be polyparticulate polysicilic microgels of surface area in excess of 1000 m2/g formed by reacting an alkali metal silicate with acid and water soluble aluminium salts, for instance as described in U.S. Pat. No. 5,482,693. Typically the polyaluminosilicates may have a mole ratio of alumina:silica of between 1:10 and 1:1500.
Polyaluminosilicates may be formed by acidifying an aqueous solution of alkali metal silicate to pH 9 or 1 0 using concentrated sulphuric acid containing 1.5 to 2.0% by weight of a water soluble aluminium salt, for instance aluminium sulphate. The aqueous solution may be aged sufficiently for the three dimensional microgel to form. Typically the polyaluminosilicate is aged for up to about two and a half hours before diluting the aqueous polysilicate to 0.5 weight % of silica.
The siliceous material may be a colloidal borosilicate, for instance as described in WO-A-9916708. The colloidal borosilicate may be prepared by contacting a dilute aqueous solution of an alkali metal silicate with a cation exchange resin to produce a silicic acid and then forming a heel by mixing together a dilute aqueous solution of an alkali metal borate with an alkali metal hydroxide to form an aqueous solution containing 0.01 to 30% B2O3, having a pH of from 7 to 10.5.
The swellable clays may for instance be typically a bentonite type clay. The preferred clays are swellable in water and include clays which are naturally water swellable or clays which can be modified, for instance by ion exchange to render them water swellable. Suitable water swellable clays include but are not limited to clays often referred to as hectorite, smectites, montmorillonites, nontronites, saponite, sauconite, hormites, attapulgites and sepiolites. Typical anionic swelling clays are described in EP-A-235893 and EP-A-335575.
Most preferably the clay is a bentonite type clay. The bentonite may be provided as an alkali metal bentonite. Bentonites occur naturally either as alkaline bentonites, such as sodium bentonite or as the alkaline earth metal salt, usually the calcium or magnesium salt. Generally the alkaline earth metal bentonites are activated by treatment with sodium carbonate or sodium bicarbonate. Activated swellable bentonite clay is often supplied to the paper mill as dry powder. Alternatively the bentonite may be provided as a high solids flowable slurry , for example at least 15 or 20% solids, for instance as described in EP-A485124, WO-A-9733040 and WO-A-9733041.
The microparticles may be made as microemulsions by a process employing an aqueous solution comprising a cationic or anionic monomer and crosslinking agent; an oil comprising a saturated hydrocarbon; and an effective amount of a surfactant sufficient to produce particles of less than about 0.75 micron in unswollen number average particle size diameter. Microbeads are also made as microgels by procedures described by Ying Huang et. al., Makromol. Chem. 186, 273-281 (1985) or may be obtained commercially as microlatices. The term "microparticle", as used herein, is meant to include all of these configurations, i.e. beads per se, microgels and microlatices.
Polymerisation of the emulsion to provide microparticles may be carried out by adding a polymerization initiator, or by subjecting the emulsion to ultraviolet radiation. An effective amount of a chain transfer agent may be added to the aqueous solution of the emulsion, so as to control the polymerization. It was surprisingly found that the crosslinked, organic, polymeric microparticles have a high efficiency as retention and drainage aids when their particle size is less than about 750 nm in diameter and preferably less than about 300 nm in diameter and that the noncrosslinked, organic, water-insoluble polymer microparticles have a high efficiency when their size is less than about 60 nm. The efficiency of the crosslinked microparticles at a larger size than the noncrosslinked microparticles may be attributed to the small strands or tails that protrude from the main crosslinked polymer.
Cationic microparticles used herein include those made by polymerizing such monomers as diallyldialkylammmonium halides; acryloxyalkyltrimethylammonium chloride; (meth)acrylates of dialkylaminoalkyl compounds, and salts and quaternaries thereof and, monomers of N,N-dialkylaminoalkyl(meth)acrylamides, and salt and quaternaries thereof, such as N,N-dimethyl aminoethylacrylamides; (meth)acrylamidopropyltrimethylammonium chloride and the acid or quaternary salts of N,N-dimethylaminoethylacrylate and the like. Cationic monomers which may be used herein are of the following general formulae:
where R1 is hydrogen or methyl, R2 is hydrogen or lower alkyl of C1 to C4, R3 and/or R4 are hydrogen, alkyl of C1 to C12, aryl, or hydroxyethyl and R2 and R3 or R2 and R4 can combined to form a cyclic ring containing one or more hetero atoms, Z is the conjugate base of an acid, X is oxygen or —NR1 wherein R1 is as defined above, and A is an alkylene group of C1 to C12; or
where R5 and R6 are hydrogen or methyl, R7 is hydrogen or alkyl of C1 to C12 and R8 is hydrogen, alkyl of C1 to C12, benzyl or hydroxyethyl; and Z is as defined above.
Anionic microparticles that are useful herein those made by hydrolyzing acrylamide polymer microparticles etc. those made by polymerizing such monomers as (methyl)acrylic acid and their salts, 2-acrylamido-2-methylpropane sulfonate, sulfoethyl-(meth)acrylate, vinyisulfonic acid, styrene sulfonic acid, maleic or other dibasic acids or their salts or mixtures thereof.
Nonionic monomers, suitable for making microparticles as copolymers with the above anionic and cationic monomers, or mixtures thereof, include (meth)acrylamide; N-alkyacrylamides, such as N-methylacrylamide; N,N-dialkylacrylamides, such as N,N-dimethylacrylamide; methyl acrylate; methyl methacrylate; acrylonitrile; N-vinyl methylacetamide; N-vinyl methyl formamide; vinyl acetate; N-vinyl pyrrolidone, mixtures of any of the foregoing and the like.
These ethylenically unsaturated, non-ionic monomers may be copolymerized, as mentioned above, to produce cationic, anionic or amphoteric copolymers. Preferably, acrylamide is copolymerized with an ionic and/or cationic monomer. Cationic or anionic copolymers useful in making microparticies comprise from about 0 to about 99 parts, by weight, of non-ionic monomer and from about 100 to about 1 part, by weight, of cationic or anionic monomer, based on the total weight of the anionic or cationic and non-ionic monomers, preferably from about 10 to about 90 parts, by weight, of non-ionic monomer and about 10 to about 90 parts, by weight, of cationic or anionic monomer, same basis i.e. the total ionic charge in the microparticle must be greater than about 1%. Mixtures of polymeric microparticles may also be used if the total ionic charge of the mixture is also over about 1%. Most preferably, the microparticles contain from about 20 to 80 parts, by weight, of non-ionic monomer and about 80 to about 20 parts by weight, same basis, of cationic or anionic monomer or mixture thereof. Polymerization of the monomers occurs in the presence of a polyfunctional crosslinking agent to form the cross-linked microparticle. Useful polyfunctional crosslinking agents comprise compounds having either at least two double bounds, a double bond and a reactive group, or two reactive groups. Illustrative of those containing at least two double bounds are N,N-methylenebisacrylamide; N,N-methylenebismethacrylamide; polyethyleneglycol diacrylate; polyethyleneglycol dimethacrylate; N-vinyl acrylamide; divinylbenzene; triallylammonium salts, N-methylallylacrylamide and the like. Polyfunctional branching agents containing at least one double bond and at least one reactive group include glycidyl acrylate; glycidyl methacrylate; acrolein; methylolacrylamide and the like. Polyfunctional branching agents containing at least two reactive groups include dialdehydes, such as gyloxal; diepoxy compounds; epichlorohydrin and the like.
Crosslinking agents are to be used in sufficient quantities to assure a cross-linked composition. Preferably, at least about 4 molar parts per million of crosslinking agent based on the monomeric units present in the polymer are employed to induce sufficient crosslinking and especially preferred is a crosslinking agent content of from about 4 to about 6000 molar parts per million, preferably, about 20-4000. More preferably the amount of crosslinking agents used is in excess of 60 or 70 molar ppm. The amounts particularly preferred are in excess of 100 or 150 ppm, especially in the range 200 to 1000 ppm. Most preferably the amount of cross-linking agents is in the range 350 to 750 ppm.
The polymeric microparticles of this invention are preferably prepared by polymerization of the monomers in an emulsion as disclosed in application, EP-484617. Polymerization in microemulsions and inverse emulsions may be used as is known to those skilled in this art. P. Speiser reported in 1976 and 1977 a process for making spherical "nanoparticles" with diameters less than 800 Ångstrom by (1) solubilizing monomers, such as acrylamide and methylenebisacrylamide, in micelles and (2) polymerizing the monomers, See J. Pharm. Sa., 65(12), 1763 (1976) and U.S. Pat. No. 4,021,364. Both inverse water-in-oil and oil-in-water "nanoparticles" were prepared by this process. While not specifically called microemulsion polymerization by the author, this process does contain all the features which are currently used to define microemulsion polymerization. These reports also constitute the first examples of polymerization of acrylamide in a microemulsion. Since then, numerous publications reporting polymerization of hydrophobic monomers in the oil phase of microemulsions have appeared. See, for examples, U.S. Pat. Nos. 4,521,317 and 4,681,912; Stoffer and Bone, J. Dispersion Sci. and Tech., 1(1), 37, 1980; and Atik and Thomas, J. Am. Chem. Soc., 103 (14), 4279 (1981); and GB 2161492A.
The cationic and/or anionic emulsion polymerization process is conducted by (i) preparing a monomer emulsion by adding an aqueous solution of the monomers to a hydrocarbon liquid containing appropriate surfactant or surfactant mixture to form an inverse monomer emulsion consisting of small aqueous droplets which, when polymerized, result in polymer particles of less than 0.75 micron in size, dispersed in the continuous oil phase and (ii) subjecting the monomer microemulsion to free radical polymerization.
The aqueous phase comprises an aqueous mixture of the cationic and/or anionic monomers and optionally, a non-ionic monomer and the crosslinking agent, as discussed above. The aqueous monomer mixture may also comprise such conventional additives as are desired. For example, the mixture may contain chelating agents to remove polymerization inhibitors, pH adjusters, initiators and other conventional additives.
Essential to the formation of the emulsion, which may be defined as a swollen, transparent and thermodynamically stable emulsion comprising two liquids insoluble in each other and a surfactant, in which the micelles are less than 0.75 micron in diameter, is the selection of appropriate organic phase and surfactant.
The selection of the organic phase has a substantial effect on the minimum surfactant concentration necessary to obtain the inverse emulsion. The organic phase may comprise a hydrocarbon or hydrocarbon mixture. Saturated hydrocarbons or mixtures thereof are the most suitable in order to obtain inexpensive formulations. Typically, the organic phase will comprise benzene, toluene, fuel oil, kerosene, odorless mineral spirits or mixtures of any of the foregoing.
The ratio, by weight, of the amounts of aqueous and hydrocarbon phases is chosen as high as possible, so as to obtain, after polymerization, an emulsion of high polymer content. Practically, this ratio may range, for example for about 0.5 to about 3:1, and usually approximates about 1:1, respectively.
One or more surfactants may be selected in order to obtain HLB (Hydrophilic Lipophilic Balance) value ranging from about 8 to about 11. In addition to the appropriate HLB value, the concentration of surfactant must also be optimized, i.e. sufficient to form an inverse emulsion. Too low a concentration of surfactant leads to inverse emulsions of the prior art and too high a concentrations results in undue costs. Typical surfactants useful, in addition to those specifically discussed above, may be anionic, cationic or nonionic and may be selected from polyoxyethylene (20) sorbitan trioleate, sorbitan trioleate, sodium di-2-ethylhexylsulfosuccinate, oleamidopropyidimethylamine; sodium isostearyl-2-lactate and the like. Polymerization of the emulsion may be carried out in any manner known to those skilled in the art. Initiation may be effected with a variety of thermal and redox free-radical initiators including azo compounds, such as azobisisobutyronitrile; peroxides, such as t-butyl peroxide; inorganic compounds, such as potassium persulfate and redox couples, such as ferrous ammonium sulfate/ammonium persulfate. Polymerization may also be effected by photochemical irradiation processes, irradiation, or by ionizing radiation with a Co60 source. Preparation of an aqueous product from the emulsion may be effected by inversion by adding it to water which may contain a breaker surfactant. Optionally, the polymer may be recovered from the emulsion by stripping or by adding the emulsion to a solvent which precipitates the polymer, e.g. isopropanol, filtering off the resultant solids, drying and redispersing in water.
The high molecular weight, ionic, synthetic polymers used in the present invention preferably have a molecular weight in excess of 100,000 and preferably between about 250,000 and 25,000,000. Their anionicity and/or cationicity may range from 1 mole percent to 100 mole percent. The ionic polymer may also comprise homopolymers or copolymers of any of the ionic monomers discussed above with regard to the ionic beads, with acrylamide copolymers being preferred.
The tan delta at 0.005 Hz value is obtained using a Controlled Stress Rheometer in Oscillation mode on a 1.5% by weight aqueous solution of polymer in deionised water after tumbling for two hours. In the course of this work a Carrimed CSR 100 is used fitted with a 6 cm acrylic cone, with a 1� 58′ cone angle and a 58 μm truncation value (Item ref 5664). A sample volume of approximately 2-3 cc is used. Temperature is controlled at 20.0� C.�0.1� C. using the Peltier Plate. An angular displacement of 5�10−4 radians is employed over a frequency sweep from 0.005 Hz to 1 Hz in 12 stages on a logarithmic basis. G′ and G″ measurements are recorded and used to calculate tan delta (G″/G′) values. The value of tan delta is the ratio of the loss (viscous) modulus G″ to storage (elastic) modulus G′ within the system.
At low frequencies (0.005 Hz) it is believed that the rate of deformation of the sample is sufficiently slow to enable linear or branched entangled chains to disentangle. Network or cross-linked systems have permanent entanglement of the chains and show low values of tan delta across a wide range of frequencies, Therefore low frequency (e.g. 0.005 Hz) measurements are used to characterise the polymer properties in the aqueous environment.
According to the invention the components of the flocculation system may be combined into a mixture and introduced into the cellulosic suspension as a single composition. Alternatively the polymeric microparticles and the siliceous material may be introduced separately but simultaneously. Preferably, however, the siliceous material and the polymeric microparticles are introduced sequentially more preferably when the siliceous material is introduced into the suspension and then the polymeric microparticles.
In a preferred form of the invention the process comprises including a further flocculating material into the cellulosic suspension before adding the polymeric microparticles and siliceous material. The further flocculating material may be anionic, non-ionic or cationic. It may be for instance a synthetic or natural polymer and may be a water soluble substantially linear or branched polymer. Alternatively the first flocculating material is a cross-linked polymer or a blend of cross-linked and water soluble polymer. In a preferred form of the invention the polymeric microparticles and siliceous material are added to the cellulosic suspension, which suspension has been pre-treated with a cationic material. The cationic pre-treatment may be by incorporating cationic materials into the suspension at any point prior to the addition of the polymeric microparticle and siliceous material.
Thus the cationic treatment may be immediately before adding the polymeric microparticle and siliceous material although preferably the cationic material is introduced into the suspension sufficiently early in order for it to be distributed throughout the cellulosic suspension before either the polymeric microparticle or siliceous material are added. It may be desirable to add the cationic material before one of the mixing, screening or cleaning stages and in some instances before the stock suspension is diluted. It may even be beneficial to add the cationic material into the mixing chest or blend chest or even into one or more of the components of the cellulosic suspension, for instance, coated broke or filler suspensions for instance precipitated calcium carbonate slurries.
The cationic material may be any number of cationic species such as water soluble cationic organic polymers, or inorganic materials such as alum, polyaluminium chloride, aluminium chloride trihydrate and aluminochloro hydrate. The water soluble cationic organic polymers may be natural polymers, such as cationic starch or synthetic cationic polymers. Particularly preferred are cationic materials that coagulate or flocculate the cellulosic fibres and other components of the cellulosic suspension.
According to another preferred aspect of the invention the flocculation system comprises at least three flocculent components. Thus this preferred system employs polymeric microparticles, siliceous material and at least one additional flocculant/coagulant.
The additional flocculant/coagulant component is preferably added prior to either the siliceous material or polymeric microparticle. Typically the additional flocculent is a natural or synthetic polymer or other material capable of causing flocculation/coagulation of the fibres and other components of the cellulosic suspension. The additional flocculant/coagulant may be a cationic, non-ionic, anionic or amphoteric natural or synthetic polymer. It may be a natural polymer such as natural starch, cationic starch, anionic starch or amphoteric starch. Alternatively it may be any water soluble synthetic polymer which preferably exhibits ionic character. The preferred ionic water soluble polymers have cationic or potentially cationic functionality. For instance the cationic polymer may comprise free amine groups which become cationic once introduced into a cellulosic suspension with a sufficiently low pH so as to protonate free amine groups. Preferably however, the cationic polymers carry a permanent cationic charge, such as quaternary ammonium groups.
The additional flocculant/coagulant may be used in addition to the cationic pre-treatment step described above. In a particularly preferred system the cationic pre-treatment is also the additional flocculant/coagulant. Thus this preferred process comprises adding a cationic flocculant/coagulant to the cellulosic suspension or to one or more of the suspension components thereof, in order to cationically pre-treat the cellulosic suspension. The suspension is susbsequently subjected to further flocculation stages comprising addition of the polymeric microparticies and the siliceous material.
The cationic flocculant/coagulant is desirably a water soluble polymer which may for instance be a relatively low molecular weight polymer of relatively high cationicity. For instance the polymer may be a homopolymer of any suitable ethylenically unsaturated cationic monomer polymerised to provide a polymer with an intrinsic viscosity of up to 3 dl/g. Homopolymers of diallyl dimethyl ammonium chloride are preferred. The low molecular weight high cationicity polymer may be an addition polymer formed by condensation of amines with other suitable di- or tri-functional species. For instance the polymer may be formed by reacting one or more amines selected from dimethyl amine, trimethyl amine and ethylene diamine etc and epihalohydrin, epichlorohydrin being preferred. Preferably the cationic flocculant/coagulant is a polymer that has been formed from a water soluble ethylenically unsaturated cationic monomer or blend of monomers wherein at least one of the monomers in the blend is cationic or potentially cationic. By water soluble we mean that the monomer has a solubility in water of at least 5 g/100 cc. The cationic monomer is preferably selected from di allyl di alkyl ammonium chlorides, acid addition salts or quaternary ammonium salts of either dialkyl amino alkyl (meth) acrylate or dialkyl amino alkyl (meth) acrylamides. The cationic monomer may be polymerised alone or copolymerised with water soluble non-ionic, cationic or anionic monomers. More preferably such polymers have an intrinsic viscosity of at least 3 dl/g, for instance as high as 16 or 18 dl/g, but usually in the range 7 or 8 to 14 or 15 dl/g.
Particularly preferred cationic polymers include copolymers of methyl chloride quaternary ammonium salts of dimethylaminoethyl acrylate or methacrylate. The water soluble cationic polymer may be a polymer with a Theological oscillation value of tan delta at 0.005 Hz of above 1.1 (defined by the method given herein) for instance as provided for in copending patent application based on the priority U.S. patent application Ser. No. 60/164,231 (reference PP/W-21916/P1/AC 526).
The water soluble cationic polymer may also have a slightly branched structure for instance by incorporating small amounts of branching agent e.g. up to 20 ppm by weight. Such branched polymers may also be prepared by including a chain transfer agent into the monomer mix. The chain transfer agent may be included in an amount of at least 2 ppm by weight and may be included in an amount of up to 200 ppm by weight. Typically the amounts of chain transfer agent are in the range 10 to 50 ppm by weight. The chain transfer agent may be any suitable chemical substance, for instance sodium hypophosphite, 2-mercaptoethanol, malic acid or thioglycolic acid.
When the flocculation system comprises cationic polymer, it is generally added in an amount sufficient to effect flocculation. Usually the dose of cationic polymer would be above 20 ppm by weight of cationic polymer based on dry weight of suspension. Preferably the cationic polymer is added in an amount of at least 50 ppm by weight for instance 100 to 2000 ppm by weight. Typically the polymer dose may be 150 ppm to 600 ppm by weight, especially between 200 and 400 ppm.
Typically the amount of polymeric microparticle may be at least 20 ppm by weight based on weight of dry suspension, although preferably is at least 50 ppm by weight, particularly between 100 and 2000 ppm by weight. Doses of between 150 and 600 ppm by weight are more preferred, especially between 200 and 400 ppm by weight. The siliceous material may be added at a dose of at least 100 ppm by weight based on dry weight of suspension. Desirably the dose of siliceous material may be in the range of 500 or 750 ppm to 10,000 ppm by weight. Doses of 1000 to 2000 ppm by weight siliceous material have been found to be most effective.
In one preferred form of the invention the cellulosic suspension is subjected to mechanical shear following addition of at least one of the components of the flocculating system. Thus in this preferred form at least one component of the flocculating system is mixed into the cellulosic suspension causing flocculation and the flocculated suspension is then mechanically sheared. This shearing step may be achieved by passing the flocculated suspension through one or more shear stages, selected from pumping, cleaning or mixing stages. For instance such shearing stages include fan pumps and centri-screens, but could be any other stage in the process where shearing of the suspension occurs.
The mechanical shearing step desirably acts upon the flocculated suspension in such a way as to degrade the flocs. All of the components of the flocculating system may be added prior to a shear stage although preferably at least the last component of the flocculating system is added to the cellulosic suspension at a point in the process where there is no substantial shearing before draining to form the sheet. Thus it is preferred that at least one component of the flocculating system is added to the cellulosic suspension and the flocculated suspension is then subjected to mechanical shear wherein the flocs are mechanically degraded and then at least one component of the flocculating system is added to reflocculate the suspension prior to draining.
According to a more preferred form of the invention the water-soluble cationic polymer is added to the cellulosic suspension and then the suspension is then mechanically sheared. The siliceous material and the polymeric microparticle are then added to the suspension. The polymeric microparticle and siliceous material may be added either as a premixed composition or separately but simultaneously but preferably they are added sequentially. Thus the suspension may be re-flocculated by addition of the polymeric microparticles followed by the siliceous material but preferably the suspension is reflocculated by adding siliceous material and then the polymeric microparticles.
The first component of the flocculating system may be added to the cellulosic suspension and then the flocculated suspension may be passed through one or more shear stages. The second component of the flocculation system may be added to re-flocculate the suspension, which re-flocculated suspension may then be subjected to further mechanical shearing. The sheared reflocculated suspension may also be further flocculated by addition of a third component of the flocculation system. In the case where the addition of the components of the flocculation system is separated by shear stages it is preferred that the polymeric microparticle component is the last component to be added.
In another form of the invention the suspension may not be subjected to any substantial shearing after addition of any of the components of the flocculation system to the cellulosic suspension. The siliceous material, polymeric microparticle and where included the water soluble cationic polymer may all be introduced into the cellulosic suspension after the last shear stage prior to draining. In this form of the invention the polymeric microparticle may be the first component followed by either the cationic polymer (if included) and then the siliceous material. However, other orders of addition may also be used.
In a further preferred form of the invention we provide a process of making paper or board in which the a cationic material is introduced into the furnish or components thereof and the treated furnish is passed through at least one shear stage selected from mixing, cleaning and screening stages and then the furnish is subjected to flocculation by a flocculation system comprising anionic polymeric microparticles and a siliceous material. As given before the anionic polymeric microparticles and siliceous material may be added simultaneously or added sequentially. When added sequentially there may be a shear stage between the addition points.
A particularly preferred process employs the organic microparticle as the major component of the total flocculation system comprising a siliceous material and organic microparticles. Hence the organic microparticle should in this case be greater than 50%, preferably greater than 55% of the total flocculation system. In this form of the invention it is highly desirable that the ratio of organic microparticles to siliceous material is in the range 55:45 and 99:1 based on weight of materials. Preferably the ratio of organic microparticle to siliceous material is between 60:40 and 90:10, more preferably between 65:35 and 80:20, especially about 75:25.
In one preferred form of the invention we provide a process of preparing paper from a cellulosic stock suspension comprising filler. The filler may be any of the traditionally used filler materials. For instance the filler may be clay such as kaolin, or the filler may be a calcium carbonate which could be ground calcium carbonate or in particular precipitated calcium carbonate, or it may be preferred to use titanium dioxide as the filler material. Examples of other filler materials also include synthetic polymeric fillers. Generally a cellulosic stock comprising substantial quantities of filler are more difficult to flocculate. This is particularly true of fillers of very fine particle size, such as precipitated calcium carbonate.
Thus according to a preferred aspect of the present invention we provide a process for making filled paper. The paper making stock may comprise any suitable amount of filler. Generally the cellulosic suspension comprises at least 5% by weight filler material. Typically the amount of filler will be up to 40%, preferably between 10% and 40% filler. Thus according to this preferred aspect of this invention we provide a process for making filled paper or paper board wherein we first provide a cellulosic suspension comprising filler and in which the suspension solids are flocculated by introducing into the suspension a flocculating system comprising a siliceous material and polymeric microparticle as defined herein.
In an alternative form of the invention we provide a process of preparing paper or paperboard from a cellulosic stock suspension which is substantially free of filler.
As an illustration of the invention a cellulosic stock is prepared containing a 50/50 bleached birch/bleached pine suspension containing 40% by weight (on total solids) precipitated calcium carbonate. The stock suspension is beaten to a freeness of 55� (Schopper Riegler method) before the addition of filler. 5 kg per tonne (on total solids) cationic starch (0.045 DS) is added to the suspension.
500 grams per tonne of copolymer of acrylamide with methyl chloride quaternary ammonium salt of dimethylaminoethyl acrylate (75/25 wt./wt.) of intrinsic viscosity above 11.0 dl/g is mixed with the stock and then after shearing the stock using a mechanical stirrer then 250 grams per tonne of a polymeric microparticle comprising anionic copolymer of acrylamide with sodium acrylate (65/35) (wt./wt.) with 700 ppm by weight methylene bis acrylamide prepared by microemulsion polymerisation as given herein is mixed into the stock. 2000 grams per tonne of an aqueous colloidal silica is applied after the shearing but immediately prior to the addition of polymeric microparticle.
We find that for doses that provide equivalent drainage and/or retention the combination of both microparticle and silica gives improved formation over the separate use of microparticle or silica.
The following Example further illustrate the invention without in any way being intended to limit the invention.
A model fine paper stock is prepared containing a fibre content comprising equal mix of bleached birch and bleached pine and contained 40%, by weight (PCC on dry fibre), precipitated calcium carbonate (Albacar HO, Specialty Minerals Inc). The stock is used at a 1% paper stock concentration.
The following ADDITIVES are used in the evaluation
CATIONIC POLYMER=High molecular copolymer of acrylamide with dimethylaminethyl acrylate, methyl chloride quaternary ammonium salt (60/40 weight/weight) then made up as a 0.1% solution.
ORGANIC-MICROPARTICLE=Anionic copolymer of acrylamide with sodium acrylate (65/35) (wt./wt.) with 300 ppm by weight methylene bis acrylamide prepared by microemulsion polymerisation as given herein, then made up in water as a 0.1% polymer concentration.
Bentonite=A commercially available bentonite clay—made up as a 0.1% solids by weight aqueous suspension using deionised water.
The single component systems are evaluated by adding the ADDITIVE at the stated dose t o 500 ml of the paper stock suspension in a 500 ml measuring cylinder and mix ed by 5 hand inversions before being transferred to the DDJ with the stirrer set at 1000 rpm. The tap was opened after 5 seconds and then closed after a further 15 seconds. 250 ml of filtrate is collected for each test.
The dual component systems were evaluated by adding the CATIONIC POLYMER at a dose of 250 grams per tonne to the stock in a measuring cylinder and mixing by five hand inversions. The flocculated stock is then transferred to a shear pot and mixed for 30 seconds with a Heidolph stirrer at a speed of 1500 rpm. The sheared stock was then returned to the measuring cylinder before being dosed with the required amount of anionic component. The re-flocculated suspension was transferred to the DDJ with the stirrer set at 1000 rpm and the filtrate was collected in the same way as specified above.
The three component system are evaluated in the same way as the dual component systems except that the ORGANIC MICROPARTICLE is added immediately after the BENTONITE addition and then mixed by hand inversions.
The blank (no chemical addition) retention value is also determined. For the blank retention, the stock is added to the DDJ, with the stirrer set at 1000 rpm, and the filtrate is collected as above.
A Schopper-Riegler free drainage survey is carried out using the same flocculation systems as described in the method for the retention survey.
All retention values shown are percentages
The blank retention is 65.1%
Dose Level (g/t)
CATIONIC POLYMER used at 250 g/t
Dose Level (g/t)
CATIONIC POLYMER used at 250 g/t
BENTONITE used at 500 g/t
Dose Level (g/t)
The results of table 3 show the benefits of using both siliceous material and organic microparticle.
All retention values shown are percentages
The blank filler retention is 31.3%
Dose Level (g/t)
CATIONIC POLYMER used at 250 g/t
Dose Level (g/t)
CATIONIC POLYMER used at 250 g/t
BENTONITE used at 500 g/t
Dose Level (g/t)
The results of table 6 show the benefits in terms of filler retention of using both siliceous material and organic microparticle.
The free drainage results are measured in seconds for 600 ml of filtrate to be collected. The blank free drainage is 104 seconds
Dose Level (g/t)
CATIONIC POLYMER used at 250 g/t
Dose Level (g/t)
CATIONIC POLYMER used at 250 g/t
BENTONITE used at 500 g/t
Dose Level (g/t)
The results of table 9 show the benefits of using both siliceous material and organic microparticle.
The First Pass Retention tests of Example 1 are repeated except using an ORGANIC-MICROPARTICLE that has been prepared using 1000 ppm by weight methylene-bis-acrylamide.
All retention values shown are percentages
The blank retention is 82.6%
Dose Level (g/t)
CATIONIC POLYMER used at 500 g/t
Dose Level (g/t)
CATIONIC POLYMER used at 500 g/t
BENTONITE used at 500 g/t
Dose Level (g/t)
The results of table 12 show the benefits of using both siliceous material and organic microparticle.
Laboratory headbox stock was prepared to 0.64% consistency with 50% hardwood fibre and 50% softwood fibre and containing 30% precipitated calcium carbonate (PCC) based on dry fibre.
The additives used are as in Example 1 except that the bentonite is replaced by a commercially available polyaluminosilicate microgel (Particol BXRTM)
A 500 ml aliquot of stock was treated for each retention test; 1000 ml was treated for free drainage testing. For single component testing, the stock was mixed at 1500 rpm for 20 seconds in a Britt jar fixed with an 80M screen. CATIONIC POLYMER was added and, after an additional 5 seconds of shear at 1000 rpm, 100 ml of whitewater was collected through the jar valve for first pass retention testing.
For the two component systems, CATIONIC POLYMER was added 10 seconds prior to the microparticle addition. Particol BX or Organic microparticle was dosed after 20 seconds of total shear. Whitewater was collected as for single component testing.
The third component was added immediately after the second component for each 3-component system.
First pass ash retention was determined by burning the dry filter pads at 525� C. for 4 hours. Free drainage testing was conducted using a Schopper-Riegler free drainage tester. The stock was mixed at 1000 rpm for a total of 30 seconds for each test. Retention aids were added in the same time intervals as retention testing.
The single component cationic flocculant was dosed at 0.25, 0.5, 0.75, 1 and 1.25 pounds per ton active. A fixed flocculant dosage was then determined from those results for use in the two- and three-component systems. Each additional component was dosed at 0.25, 0.5, 0.75, 1 and 1.25 pounds per ton active. The second components were fixed at 0.75 pounds per ton active for the three-component systems.
The results are shown in FIGS. 1 through 3.
FIG. 1 shows the first pass retention performance of the various systems. The components used for each system are listed in the legend with the final component dosage used as the x-axis. FIG. 1 shows that the highest advantage in first pass retention can be achieved by adding organic microparticle as the final component in the three-component system with microgel Particol BX.
Similar trends in first pass ash retention performance are shown in FIG. 2 for the same systems used with Particol BX. The advantage in ash retention is demonstrated by the addition of Organic microparticle to the Particol system.
FIG. 3 shows the free drainage performance of the microparticle systems tested.
Example 3 demonstrates the improvements over the two component systems using cationic polymer a polysilicate microgel and organic microparticle over the two component systems using cationic polymer and either organic microparticle or polysilicate microgel.
|Cited Patent
|Filing date
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|4 Dec 1973
|3 May 1977
|Prof. Dr. Peter Speiser
|Microcapsules in the nanometric range and a method for their production
|26 Feb 1981
|14 Jun 1983
|Eka Aktiebolag
|Papermaking and products made thereby
|8 Apr 1983
|4 Jun 1985
|Institut Francais Du Petrole
|Process for manufacturing a microlatex in a continuous oil phase by polymerization of a water-soluble monomer in a water-in-oil microemulsion, resultant microlatices, and their use for enhanced oil recovery
|7 Jun 1985
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|Institut Francais Du Petrole
|Process for manufacturing inverse microlatices of watersoluble copolymers, the resultant inverse microlatices and their use for improving the production of hydrocarbons
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|2 Jun 1993
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|Process for the manufacture of a paper or a cardboard having improved retention
|19 Jul 1993
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|14 Mar 1994
|9 Jan 1996
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|21 Jan 1994
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|Allied Colloids Limited
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|21 Feb 1995
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|E. I. Du Pont De Nemours And Company
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|1 Jun 1995
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|24 Oct 1997
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|Method for treating suspended solids
|14 Oct 1998
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|Nalco Chemical Company
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|13 May 1998
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|20 Jan 1987
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|Allied Colloids Limited
|Production of paper and paperboard
|9 Sep 1988
|29 Mar 1989
|Nalco Chemical Company
|Method for dewatering paper
|22 Mar 1989
|10 Mar 1993
|Allied Colloids Limited
|Production of paper and paper board
|27 Mar 1991
|27 Dec 1991
|Cytec Technology Corp.
|Charged organic polymer microbeads in paper making process
|15 Apr 1991
|13 May 1992
|Cytec Technology Corp.
|Cross-linked anionic and amphoteric polymeric microparticles
|1 Nov 1991
|13 May 1992
|Allied Colloids Limited
|Paper making process
|Title not available
|6 Jun 1985
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|Eka Ab
|Papermaking process
|10 Mar 1997
|12 Sep 1997
|Allied Colloids Limited
|Activation of swelling clays and processes of using the activated clays
|10 Mar 1997
|12 Sep 1997
|Allied Colloids Limited
|Clay compositions and their use in paper making
|30 Dec 1997
|9 Jul 1998
|Ciba Specialty Chemicals Water Treatments Limited
|Processes of making paper and materials for use in this
|17 Sep 1998
|8 Apr 1999
|Nalco Chemical Company
|Colloidal borosilicates and their use in the production of paper
|2 Nov 2000
|17 May 2001
|Ciba Specialty Chemicals Water Treatments Limited
|Manufacture of paper and paperboard
|S. Atik et al., J. Am. Chem. Soc. (1981), vol. 103, pp. 4279-4280.
|Stoffer et al., J. Dispersion Sci. and Tech., vol. 1, No. 1, (1980), p. 37.
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|Citing Patent
|Filing date
|Publication date
|11 Jun 2002
|13 Mar 2007
|Akzo Nobel N.V.
|Aqueous composition
|21 Feb 2006
|6 Apr 2010
|Akzo Nobel N.V.
|Aqueous composition
|5 Sep 2006
|5 Apr 2011
|Basf Aktiengesellschaft
|Method for the production of paper, cardboard and card
|14 Dec 2005
|7 Jun 2011
|Akzo Nobel N.V.
|Process for the production of paper
|14 Sep 2006
|19 Jul 2011
|Kemira Oyj
|Method for paper processing
|14 Sep 2007
|18 Oct 2011
|Kemira Oyj
|Composition and method for paper processing
|28 Apr 2009
|3 Jan 2012
|Nalco Company
|Controllable filler prefloculation using a dual polymer system
|12 Sep 2007
|8 May 2012
|Nalco Company
|Controllable filler prefloculation using a dual polymer system
|20 Dec 2006
|25 Sep 2012
|Akzo Nobel N.V.
|Process for the production of paper
|8 May 2009
|13 Nov 2012
|Hercules Incorporated
|Retention and drainage in the manufacture of paper
|3 May 2011
|13 Nov 2012
|Akzo Nobel N.V.
|Process for the production of paper
|10 Apr 2009
|1 Jan 2013
|S.P.C.M. Sa
|Method for producing paper and cardboard
|22 Dec 2010
|26 Feb 2013
|Nalco Company
|Recycling of waste coating color
|30 Apr 2008
|2 Jul 2013
|Bayer Innovation Gmbh
|Metal salt nanogel-containing polymers
|26 Oct 2011
|9 Jul 2013
|Buckman Laboratories International, Inc.
|Papermaking and products made thereby with ionic crosslinked polymeric microparticle
|3 Nov 2010
|22 Oct 2013
|Applied Chemicals Handels-Gmbh
|Method for producing paper
|18 Apr 2012
|10 Jun 2014
|Nalco Company
|Controllable filler prefloculation using a dual polymer system
|1 Nov 2012
|15 Jul 2014
|Nalco Company
|Preflocculation of fillers used in papermaking
|10 Oct 2012
|29 Jul 2014
|Akzo Nobel N.V.
|Process for the production of paper
|6 Sep 2012
|18 Nov 2014
|Akzo Nobel N.V.
|Process for the production of paper
|11 Oct 2013
|22 Sep 2015
|Akzo Nobel N.V.
|Process for the production of paper
|17 Jun 2013
|8 Nov 2016
|Nalco Company
|Method of improving dewatering efficiency, increasing sheet wet web strength, increasing sheet wet strength and enhancing filler retention in papermaking
|10 Jul 2014
|7 Feb 2017
|Akzo Nobel N.V.
|Process for the production of paper
|25 Feb 2013
|25 Apr 2017
|Basf Se
|Process for the manufacture of paper and paperboard
|14 Jul 2014
|5 Sep 2017
|Ecolab Usa Inc.
|Anionic preflocculation of fillers used in papermaking
|11 Jun 2002
|26 Dec 2002
|Duncan Carr
|Aqueous composition
|14 Dec 2005
|22 Jun 2006
|Akzo Nobel N.V.
|Process for the production of paper
|21 Dec 2005
|29 Jun 2006
|Sutman Frank J
|Retention and drainage in the manufacture of paper
|21 Dec 2005
|29 Jun 2006
|Gelman Robert A
|Retention and drainage in the manufacture of paper
|21 Dec 2005
|29 Jun 2006
|Harrington John C
|Retention and drainage in the manufacture of paper
|21 Dec 2005
|29 Jun 2006
|Sutman Frank J
|Retention and drainage in the manufacture of paper
|21 Dec 2005
|29 Jun 2006
|Harrington John C
|Retention and drainage in the manufacture of paper
|21 Feb 2006
|29 Jun 2006
|Akzo Nobel N.V.
|Aqueous composition
|21 Dec 2005
|28 Dec 2006
|Fushan Zhang
|Retention and drainage in the manufacture of paper
|20 Dec 2006
|5 Jul 2007
|Akzo Nobel N.V.
|Process for the production of paper
|14 Sep 2006
|20 Mar 2008
|Marco Savio Polverari
|Composition and method for paper processing
|14 Sep 2007
|5 Jun 2008
|Kemira Oyj
|Composition and method for paper processing
|5 Sep 2006
|21 Aug 2008
|Basf Se
|Method For the Production of Paper, Cardboard and Card
|12 Sep 2007
|12 Mar 2009
|Weiguo Cheng
|Controllable filler prefloculation using a dual polymer system
|28 Apr 2009
|29 Oct 2009
|Weiguo Cheng
|Controllable filler prefloculation using a dual polymer system
|10 Apr 2009
|12 Nov 2009
|Snf Sas
|Method for producing paper and cardboard
|30 Apr 2008
|15 Jul 2010
|Helling Innovation Ug
|Metal salt nanogel-containing polymers
|22 Dec 2010
|21 Apr 2011
|Weiguo Cheng
|Recycling of waste coating color
|3 Nov 2010
|6 Sep 2012
|Alexander Frank
|Method for producing paper or the like
|25 Feb 2013
|29 Jan 2015
|Basf Se
|Process for the manufacture of paper and paperboard
|14 Sep 2007
|31 Aug 2016
|Kemira Oyj
|Process for making paper or paperboard
|22 Dec 2005
|6 Jul 2006
|Hercules Incorporated
|Improved retention and drainage in the manufacture of paper
|22 Dec 2005
|6 Jul 2006
|Hercules Incorporated
|Improved retention and drainage in the manufacture of paper
|22 Dec 2005
|6 Jul 2006
|Hercules Incorporated
|Improved retention and drainage in the manufacture of paper
|22 Dec 2005
|6 Jul 2006
|Hercules Incorporated
|Improved retention and drainage in the manufacture of paper
|12 Sep 2008
|19 Mar 2009
|Nalco Company
|Controllable filler prefloculation using a dual polymer system
|18 Oct 2013
|8 May 2014
|Nalco Company
|Preflocculation of fillers used in papermaking
|12 Oct 2015
|20 Apr 2017
|Solenis Technologies, L.P.
|Method of increasing drainage performance of a pulp slurry during manufacture of paper products, and products therefrom
|U.S. Classification
|162/168.1, 162/168.3, 162/181.6, 162/183, 162/168.2, 162/181.8
|International Classification
|Cooperative Classification
|European Classification
|15 Jan 2002
Owner name: CIBA SPECIALTY CHEMICALS WATER TREATMENTS LIMITED,
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CHEN, GORDON CHENG I;RICHARDSON, GARY PETER;REEL/FRAME:012484/0487;SIGNING DATES FROM 20010802 TO 20010916
|28 Jul 2006
|Fee payment
Year of fee payment: 4
|18 Aug 2010
|Fee payment
Year of fee payment: 8
|20 Aug 2014
|Fee payment
Year of fee payment: 12


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38 year old woman | Arnold, MD, United States | Seeking men 33-45 within 50 miles
The hardest 10 yards of any workout are the 10 yards from the couch to the door.
Starting off with the standard cliche, I'm really at a loss as to what exactly to write here. I like to think I'm complicated enough to make it difficult to sum it up in 4,000. I have a degree in physics and currently do public outreach, meaning my job is to get people excited about physics. I do all sorts of things to do this, but my favorit is the series of comics I write about a laser super hero. Its neat to watch it go from a small idea into something big. Outside of work, I'm an endurance athlete, specifically triathlons. In general, I pretty much like my life. I love training for endurance sports. There is nothing like the feeling of pushing yourself to be better, trying to go just a little bit harder than last time and "embracing the suck" to push through the pain. I've been told I have a wicked sense of humor and am on the sarcastic side. I love making people laugh and in tense situations I tend to fall back on humor because nothing puts everyone at ease like a good one liner. I am very independent and very much into my own activities. But I also love time with others. I'm looking for someone that does their own thing, but is interested in spending time with me too. I put a lot of heart and soul into both my job and my training, but that doesn't mean that is all I want to do. But I am looking for someone that is ok with the fact I can be fiercely independent at times.
Coffee and conversation , Movies/Videos , Exploring new areas , Nightclubs/Dancing , Video games
Cycling, Dancing, Other types of exercise, Running, Swimming, Weights / Machines
I exercise 5 or more times per week.
Don't display my sign
I have Cats, Fish
Very Liberal
Bryn Mawr College, Bryn Mawr, PA
I love many different books but my favorite is Anna Karenina. I love country music and am an avid watcher of Jeopardy. I'm also a huge fan of This American Life, Wait Wait Don't Tell Me, The Moth and Radiolab.
I like to read but with training for triathlons and work, I don't get to do it near enough. I love doing triathlons and training for the Longhorn half ironman. I just signed up for Ironman Lake Placid 2013 and I'm already nervous.
The last thing I read was Swiftly Tilting Planet. I think it is maybe the 5th time I've read it. I haven't started anything new yet, but I hear Middlesex is really good.
Z{{Cta}} {{#if HasMoreInfo}} ?{{CtaSecondary}} {{/if}}
|What she is looking for
|5'8" (172cms)
|5'11" (180cms) to 6'6" (198cms)
|Body type:
|About average
|Slender, About average, Athletic and toned
|No preference
|No preference
|No Way
|No Way
|Social Drinker
|No preference
|Other profession
|No preference
I do physics public outreach. This means my job is to get people interested and excited about physics. Basically, I run a website, come up with fun experiments, write comic books and am a part time superhero.
|I'll tell you later
|No preference
|No preference
|Have kids:
|Yes, and they sometimes live at home, No, Yes, and they live at home
|Wants kids:
|Definitely, Someday
|White / Caucasian
|White / Caucasian
|Christian / Protestant
|No preference
|Religious Attitude:
|I'll tell you later
|No preference
|PhD / Post Doctoral
|Graduate degree

subset: commoncrawl


text:
41419 / 45608 Adverts
House Detached, single storey, separate entrance, in a property
from $29/Night (rates)
6 people 4 adults, 2 kids
3 bedrooms
3 roomsLiveable floor area : 1,300 Sq.ft.
3 bedrooms
3 roomsLiveable floor area : 1,300 Sq.ft.
- View : Unobscured, courtyard
- Kids welcome
- Setting : Ocean, Urban
- Sandy beach at 0.3mi.
- Golf, Thalasso, Festival, Horse riding, Fishing
- Pets friendly
- Exposure : North
Touristic region : discover Sardinian Coast, Costa Rei Bay, Tyrrhenian Sea, Sarrabus Gerrei, Gulf of the Angels
Advert No. 21631
For your guidance
Contact by phone
Contact by email
For safety and quality control reasons, we strongly recommend to contact the owner through IHA Holiday Ads.
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Advert 21631Villasimius - Cagliari Province - Italy
Advert details 21631
Assets House
Parking : Parking uncovered : 1 internal.
Interior House with View: unobscured, courtyard
Receive up to : 6 person(s) (4 adults, 2 kids)
Liveable floor area : 1,300 Sq.ft.
Interior layout : 3 Room(s), 3 bedroom(s), 2 bathroom, 3 shower room, 2 toilets, sitting room, separate kitchen
Sleeps - bed(s) : 3 full bed(s), 2 baby cradle
Guest facilities : Fireplace, T.V., wardrobe, wood-burning stove, Drapes
Appliances : Crockery/flatware, kitchen utensils, cafetiere, gaz stove, oven, electric fries fryer, extractor hood, refridgerator, deep freeze, washing machine
Exterior Vacation rental in Setting: ocean, urban
Outside accommodation : Roof terrace, pergola
Outside setting : Private courtyard
Outside amenities : BBQ, yard table(s), 6 yard seat(s), trolley on wheels, outside shower facilities
Rates Calendar Availability Vacation rental in Villasimius
Seasons & Availability House in Villasimius
Rates House in Villasimius
(Minimum Night)
Season Night Weekend week 2 weeks Month
Low season$29* (4) - - - -
Mid season$41* (4) - - - -
High season$53* (4) - - - -
Festive specials - - - - -
Promotional period - - - - -
ServiceFrequencyIncluded / SuppliedSupplementRates
Single family home
Cleaning on departure$59
For your guidance
Information :
Kids welcome
Pets friendly
Non smoking rental
Cell phone network coverage
Water : hot/cold
Local voltage supply : 220V / 60Hz
Electricity supply : mains
Booking conditions
Reservation :
Payment made upon reservation : 20% of rental sum
Payment balance : 1 month before the stay
Deposit required : $352*
rentals :
Service charges to be added
Cleaning charge levy on departure : $59*
Accepted methods of payment :
Bank transfer (wire)
Leisure, Surroundings, Location Home 21631
Leisure Villasimius - Cagliari Province
Specific activities on site or less than 3 miles :
GOLF Cagliari Province
HORSE RIDING Cagliari Province
FISHING Sardinia
THALASSO Villasimius
FESTIVAL Villasimius
Leisure activities less than 12 miles : Bathing, pedalo, snorkelling, scuba diving, banana boat, water skiing, jet ski, surfing, windsurfing, sailing, kite surfing, canoeing, golf, tennis, riding school, hiking, rappel, mountain bike (path), parascending, boat trips, horse trecking, mini-golf, rollerblade/rollerskate (circuit), skate board (ramps), basketball, volleyball, fishing, fishing, spear fishing, pétanque field
Supervised : Sailing school, dive school, tennis school, riding school
Attractions and relaxation : Bar/pub, discotheque, restaurant, open air summer movie theater, karaoke, park and garden, leisure park, sea world, nature reserve, exhibition center, art gallery, historical site, festivals, local craftstore, cellar and wine tasting, race track, natural spring baths, thalassotherapy center, sauna, steam baths, health spa, beauticians, fitness center
SurroundingsOcean - Cagliari Province
Locality :
Sandy beach at 0.3mi.
Sea inlet at 0.62mi.
9 hole golf course at 1.25mi.
Windsurfing spots at 0.5mi.
Surfing spots at 0.5mi.
Marina at 1.85mi.
Amenities :
Village center at <165'
Bike/mountain bike hire at 660'
Scooter/motorbike hire at 660'
Car rental at 660'
Boat rental at 1.85mi.
Scuba diving material hire at 0.93mi.
Breadstore at 660'
Local stores at 165'
Supermarket at 660'
High class retailers at 165'
Hairdressing salon at 330'
Internet cafe at 330'
Mail office at 990'
Bank at 660'
Drugstore at 990'
Doctor at 990'
Hospital at 12.5mi.
Dispensary at 990'
Location AccessHouse Villasimius
via regina margherita 25
09049 VillasimiusSardinia
GPS coordinates of accommodation
Latitude 39°7'42"N
Longitude 9°30'44"E
Access routes Vacation rental 21631
at 31mi. / 1h
Airport Cagliari Elmas
Cagliari, Cagliari Province, Sardinia, Italy
at 30mi. / 50min.
Sea port Cagliari
Cagliari, Cagliari Province, Sardinia, Italy
at 81mi. / 2h 30min.
Sea port Tortolì Arbatax
Tortolì, Ogliastra Province, Sardinia, Italy
Close to Monte Genis, Golfo di Carbonara, Punta Moitzus, Bruncu Campulongu, Montixeddu, Monte Luab, Scoglio Proci, Fiume Flumendosa, Punta Santa Caterina, Punta Marturedda, Scoglio San Stefano, Bruncu Tiriarxiu, Staini Simbirizzi, Riu Cixerri, Monte Turno, Porto d'Agumu, Scoglio Sant'Elia, Saline di Macchiareddu, Isola dei Cavoli, Punta Furcadizzo, Punta d'Agumu
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text:
Experts on deteriorating state of Rena
Peter Griffin posted in oil spill • rena • Tauranga on October 18th, 2011.
The stricken container ship Rena is being hit with four metre swells hampering efforts to remove oil and prevent further major spillages should the ship break up. The latest official update from Maritime New Zealand is here. The SMC posed questions to international naval architecture experts on the forces at play in the damaged ship […]
Continue reading "Experts on deteriorating state of Rena"


text:
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text:
Some teachers in the Perris Union High School District are angry over a salary and benefits package they voted on Wednesday that did not include a pay increase for teachers with the most education and experience, and that would require them to supervise their campuses during the school day.
Teachers interviewed Wednesday contended they are already underpaid compared to neighboring districts and therefore were disappointed that veterans weren't offered increased salaries.
"I don't think the district will give us anything reasonable," said Fred Twyman, a math teacher at Paloma Valley High School in Menifee. "We're the lowest paid district in the county."
If the benefits contract is approved by the teachers' union, it will become part of their overall contract, which also was up this year. However, negotiations for that document are ongoing because the district is working on a one-year extension.
The union, which represents teachers from Paloma Valley along with several schools in Perris, will announce the outcome of the vote today.
Members of the union, which has about 300 people, including teachers, counselors and psychologists, voted on a package that includes fully paid health coverage and $200 a year for employees in exchange for supervising the school campus 10 minutes daily one week per month.
The contract also includes a salary increase of between a quarter of a percent to 5 percent for teachers in the low and middle part of the pay scale, but first-year teachers and those at the very highest portion of the scale would not receive the increase, said Joe Daugherty, school board president and a member of the district's negotiating team.
The salaries for first-year teachers already were increased several years ago because starting teachers' pay was about $5,000 below other districts in the county, he said. Teachers also get pay increases for every 15 credits of education they receive and longevity bonuses for being with the district more than 14 years.
The salary increase mainly is intended to boost teachers in the middle portion of the pay scale at a time in their careers when they are tempted to find higher paying jobs with other districts, Daugherty said.
If teachers do not approve the contract, their benefits will revert back to the 2002-03 year's package, which included out-of-pocket expenses of up to several hundred dollars per month, depending on the plan, district officials said.
Lorna Hulstrom, president of the union and a teacher at Perris High School, said the district's overall approach to benefits is fair, but it still leaves salaries far behind other districts, and salaries are an important part of recruiting qualified teachers.
"To be fair, we're one of the few that have fully paid benefits," Hulstrom said. "Most of the districts have some out of pocket (expenses). If you look at the entire package, we're not as bad as it looks, but if you look at salary, yes, we are."
Assistant Superintendent Barry Kayrell said the district can't put an equal amount into salaries if it fully funds health plans.
"We're second in the county in terms of health and welfare (benefits)," Kayrell said. "So we've been pumping hundreds of thousands into that schedule."
The contract also includes a class-size reduction from 37 students per teacher to 36 per teacher, Daugherty said.
If the contract does not pass, union representatives have asked that it be renegotiated. It requires 51 percent approval to pass.
District officials said they included the supervision requirement to provide extra safety at the campuses, not out of a perceived threat or because of discipline problems. Teachers would patrol the campuses before and after school, during passing periods and lunch.
However, teachers say their days are busy enough without cramming the extra supervision duty in. Twyman, who also is leading an effort to pull Paloma Valley from the Perris district and join it with Menifee, said many teachers already put in extra hours tutoring students or working with them after school and in extracurricular activities.
For the whole year, "I only get $200 (for) 10 minutes of supervision a week," said Twyman, who is running for the position of union president. "I'm already doing way over (what's required)."
Another teacher, who asked not to be named, said some teachers took the offer of $200 a year as an insult.
"Teachers are offended. The time we have is invaluable," the teacher said.
Daugherty, the school board president, said security guards can only be in one place at a time, and the district cannot afford to hire the number of guards that would provide the same level of supervision as teachers at the schools.
"If you have four teachers each doing 10 minute shifts that day …. you can get more exposure," he said. "I don't think it's a lot to ask."
Contact staff writer Kelly Brusch at (909) 676-4315, Ext. 2626,or firstname.lastname@example.com.


text:
City Judge Susan "Tina" Gordon presides over the City's Court, which is located inside City Hall at 130 6th Street West.
To contest a charge, you must appear
on a Monday at 9:00 a.m. prior to the date of appearance
indicated on your citation.
If you do not have a mandatory appearance, you may pay your
violations on-line at:
Facts and Figures
- Fines can be mailed to City Court, PO Box 2735, Columbia Falls, MT 59912.
- The court can be reached at 406-892-4340.
- Monday through Thursday 8:30 am to 4:00 pm. Court is closed on Friday.
City Attorneys
City Attorney Justin Breck and Deputy City Attorney Stephanie Breck provide legal guidance to the City and prosecute violations of City Ordinances.
Looking for our Municipal Code?
Click here: https://www.cityofcolumbiafalls.org/municipal-code
Looking for the laws of the State of Montana?
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Curious about proposed changes in City ordinances?
Visit our Pending Ordinances page.


text:
Sunseeker 30m Yacht Barcos en venta
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Description she is an absolutely stunning example of the Sunseeker 30 Metre Yacht, featuring accommodation for 10 guests in 5 cabins with up to 7 crew. Built in 2010 and powered by twin MTU 12V 2000 Series M94 engines with low hours, boasts an extensive specification with numerous upgrades as well as a fully Custom Master Suite option that transforms the ever-popular Sunseeker 30 Metre Yacht Owner's Suite into a space to rival her larger siblings. Beautifully maintained and finished in Black American Walnut with cream carpets and cream leather sofas/head linings she is a stunning vessel that must be viewed to be appreciated. She offers exemplary accommodation for 10 guests in 5 well-appointed staterooms and comprises of an enlarged custom main deck split level owners suite with luxurious sunken bathroom incorporating a spa style bath tub and walk in shower. On the Lower Deck there are two beautifully appointed double ensuite cabins aft, a further two ensuite twin cabins port and starboard in the mid section There is a accommodation for up to seven crew, with two crew quarters located bow and stern. Some of her features include. ? Trac Digital Fin Stabilisers ? Satellite TV ? Williams 505 Diesel Jet Tender ? Hydraulic bow and stern thrusters ? Gulf specification air conditioning ? FLIR pan and tilt night vision camera ? Upgraded generators to twin 50kWMás20Vendedor avc marine europe Ltd
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text:
RE: will deer eat grass
Deer may eat some grass but it's not very common. Most times people see them eating in a yard or golf course and think the are eating grass but that's not the case most times. They are picking out other plants like clover instead. Read this study...is interesting
Wildlife Management Handbook V-A 1
White-tailed Deer Competition with Goats, Sheep, Cattle
and Exotic Wildlife
W. E. Armstrong
Texas Parks and Wildlife Department
Hunt, Texas
Deer management is a relatively simple process. If Bites of plants that these animals consumed were recorded
you can grow deer foods, you can grow deer. By by species at weekly intervals over a year's period of time.
understanding deer food habits in relation to livestock food The same animals were then taken to a pasture that was
habits, the land manager can manipulate both livestock heavily grazed by cattle, sheep and goats at a rate of one
and deer numbers to grow more deer foods. AU per 8 acres. This pasture also contained white-tailed
Kinds of Forages
Today's rangelands are capable of producing a given
quantity of forage. This forage can broadly be divided into
three groups"forbs, browse and grass.
Forbs are best defined as broadleaved flowering
plants which most people call weeds. Although many are
perennials or biennials, most are annuals. Forbs are
generally seasonal with the greatest abundance being in
the spring, depending on local rainfall patterns. As a
group, they are high in protein. Examples of forbs are
velvet bundleflower, mat euphorhia, Dakota verbena and
knotweed leafflower.
Browse plants are shrubby or woody plants. They are
deeper rooted, more drought-resistant plants than most
forbs or grasses. As a group, they are lower in protein than
forbs. Examples of browse plants would be hackberry, live
oak, Texas oak and guayacan.
Grasses are those plants with long narrow leaves,
jointed stems, flowers in spikelets and a seedlike fruit.
Most of the major grasses are perennial and lower in
protein than forbs. Examples of grasses would be little
bluestem, Indiangrass, Texas wintergrass, johnsongrass
and fescuegrass.
Food Habits of White-Tailed Deer
and Domestic Livestock
Many food habit studies of white-tailed deer have
been conducted throughout the state of Texas. Several of
these studies were concerned not only with the food habits
of white-tailed deer, but also with the competitive effects
of domestic livestock on white-tailed deer food habits.
In the 196Os, the Kerr Wildlife Management Area
conducted a series of studies to determine the food habits
of white-tailed deer, domestic sheep, Angora goats and
cattle under three different grazing conditions. In this
study, a tame deer, sheep, goat and cow were taken to a
96-acre exclosure that had not been grazed by domestic
livestock or deer for a period of 6 years prior to the study.
deer. The experimental animals' food habits were recorded
in this pasture. The third pasture to which the animals
were taken contained only white-tailed deer. Deer
numbers in this pasture were at saturation level. Bites of
food by these animals were also recorded in this pasture.
The results of these bite studies were then totaled.
Comparisons were made between the heavily grazed
pasture, the deer-only pasture and the exclosure. In the
exclosure, when given a free choice of what it wanted to
eat, the white-tailed deer preferred forbs when they were
available. As forbs became unavailable in the summer and
fall, the white-tailed deer began to shift its diet to browse.
Grass never accounted for more than 15 percent of the
deer's diet, even in the heavily grazed pasture where forbs
and browse were in short supply and competition for food
was severe.
Just as deer were primarily forb eaters, so were sheep.
But as forbs began to disappear in the summer and fall, the
sheep began to eat both grass and browse. In the heavily
grazed pasture, grass accounted for the major portion of
the sheep's diet.
Goats were primarily browsers, taking some forbs
when available. In the exclosure, when given a free choice
of plant species, goats did not consume a large quantity of
grass. In the heavily grazed pasture, goats did consume a
larger quantity of grass than deer but were still primarily
browse eaters.
Cattle in the ungrazed exclosure preferred grass,
taking some forbs and browse. During the winter, cattle on
the Kerr Area took a surprisingly large amount (73
percent) of liveoak, which is an evergreen. In the heavily
grazed pasture, cattle were primarily grass eaters.
Analysis of the bite study data suggests that cows,
sheep and goats can survive on three classes of forage,
whereas the white-tailed deer readily utilizes only two
classes of forage (forbs and browse). This is not to say that
deer do not eat grass. Bite studies on the Texas
Agricultural Experiment Station at Sonora indicate that
deer will utilize as much as 20 percent grass in their
V-A 2 Wildlife Management Handbook
diets on those occasions when grass is in a "lush" or rapid 3. a pasture that was being grazed by domestic
state of growth. On the Experiment Station, this was livestock at a rate of one AU per 16 acres.
primarily johnsongrass and cane bluestem, following 11
inches of rain in July. However, grasses only accounted for
8 percent of the deer's total yearly diet. As grasses matured
and became more coarse, deer began to avoid them.
Deer Digestion
Studies of deer digestion by Short indicate that deer
do not digest coarse fibered plants as readily as low
fibered plants. In addition, it has also been determined that
browse plants high in oil content inhibit the "fermentation"
process in deer. Domestic livestock are more efficient in
digestion of these plants. It is not unusual to find deer
which have "starved" with a paunch full of grass.
Effects of Competition for Food
on White-tailed Deer
Evidence of the effects of competition by domestic
livestock on white-tailed deer were also studied on the
Agricultural Experimental Ranch at Sonora. Deer
populations were monitored on pastures that were
continuously stocked at heavy, moderate and light grazing
rates. Deer numbers were greatest in the lightly stocked
pastures as opposed to the heavily stocked pastures. In
pastures stocked with goats, sheep or cattle, the fewest
deer were found in the heavily grazed sheep pasture (one
deer to 40 acres) as well as the goat pasture (also one deer
to 40 acres). Light grazing with sheep only produced one
deer per 20 acres. Light grazing with goats produced one
deer per 32 acres. One deer per 15 acres and one deer per
7.3 acres were recorded in the heavily and lightly stocked
cattle only pastures, respectively.
The deer were avoiding those areas in which domestic
livestock were depleting browse and forb populations.
Classes of livestock coupled with stocking rates influence
forb and browse production. This in turn influences deer
carrying capacity.
Food Habits of Exotics
Food habit studies have also been conducted with
axis, silo and fallow deer, as well as with blackbuck
antelope and aoudad sheep. These were conducted on the
Kerr Area and the results are in the process of being
published. The study utilized the animal bite method. Food
habits were studied in three different pastures under three
different grazing conditions. Grazing conditions were:
1. a non-grazed pasture in which no livestock or
deer had been grazed for a minimum of 15 years
prior to the study,
2. a pasture containing white-tailed deer only (at
carrying capacity), and
Results of these studies indicate that these major
exotics can effectively utilize three classes of forage. As
far as food habits are concerned, they are either "sheep" or
"goats" in deer clothing. That is, they prefer forbs or
browse but are able to shift their diets to grass without
apparent signs of malnutrition.
Effects of Exotic Competition
As an extension of this study, six sika deer and six
white-tailed deer were placed in a 96-acre pasture. No
hunting or predation occurred in the pasture. Sika deer and
white-tailed deer increased to 27 and 18, respectively, on
96 acres before competition for food became severe.
White-tailed deer at this time decreased to six animals.
Sika deer increased to 32 during the same period. By the
ninth year of study, there were 59 sika deer and no whitetailed
deer alive in the pasture.
A similar study was carried out with axis deer and
white-tailed deer with similar results. Populations of axis
and white-tailed deer reached peaks of 16 axis and 15
white-tailed deer before competition for forbs and browse
became severe. White-tailed deer populations decreased
to three animals at the end of the study while axis
populations were at 16 animals in 96 acres.
In both cases, exotics and white-tailed deer depleted
a food supply causing losses in white-tailed deer. Exotics
shifted their diets to grass, survived and reproduced. By
maintaining grazing pressure on white-tailed deer foods,
exotics depleted white-tailed deer foods from the pasture.
Loss of foods resulted in losses of white-tailed deer.
Conclusions drawn from the studies conducted on
food habits of white-tailed deer, domestic livestock and the
major exotics found in Texas suggest that white-tailed
deer are able to utilize a more narrow range of plants
(plants low in cellulose fiber or low in oils) than either
domestic livestock or exotics.
Sheep are competitive with white-tailed deer primarily
for the higher protein forbs, while goats compete
with deer for the more stable drought-resistant browse.
Cattle on properly stocked ranges are the least competitive
with white-tailed deer. No conclusions were drawn on the
effects exotics have on domestic livestock although it
seems obvious that many exotics would be highly
competitive with domestic livestock, especially goats.
Our ranges only produce a given quantity of forbs and
browse. If a given range will produce enough
Wildlife Management Handbook V-A 3
forbs or browse to produce 100 animals and if 90 of them result will be small, stunted deer with poor antler
are goats and 10 are white-tailed deer, then the 10 white- development, low fawn production and frequent die-offs.
tailed deer will have adequate diets and grow into healthy
animals. If 90 are white-tailed deer and 10 are goats, then
all will be healthy animals.
The problem comes when we overstock our ranges support a given number of animals. By analyzing the
with domestic livestock as well as white-tailed deer. competition for forages available and adjusting both
White-tailed deer, which are not as competitive as the domestic livestock, exotic and native deer numbers to this
domestic livestock, will suffer from malnutrition. The forage, we can produce healthy, good quality, high
In conclusion, our ranges are capable of producing a
given quantity of forage comprised principally of forbs,
browse and grasses in varying amounts. This forage will
producing animals.
Appendix I
The following is a list of some of the more preferred food items in the white-tailed deer diet. Since browse plants are
the more stable range plant in the deer's diet (not as weather related as forbs), browse plants are good indicators of deer
range. Adequate forb production should release grazing pressure on browse. Heavy dependence on browse in the spring and
early summer indicates an overpopulation of forb or browsing animals. This, in turn, inhibits good deer production.
Selected South Texas forage plants:
Pricklypear cactus
Opuntis lindheimeri
Mesquite mast
Prosopis glandulosa
La coma
Bumelia celastrina
Celtis pallida
Catclaw acacia
Acacia greggii
Desert lantana
Lantana macropoda var. albiflora
Lime pricklyash
Zanthoxylum fagara
Poelieria angustifolia
Allthorn castela
Castela texana
Texas silverleaf
Leucophyllum frutescens
Texas colubrina
Colubrina texensis
Perennial lazy daisy
Aphanostephus riddellii
Kidder dosedaisy
A. kidderi
Dayflower sp.
Commelina sp
Prostrate euphorbia
Euphorbis prostrata
Selected Rolling Plains forage plants:
Phoradendron serotinum var. pubescens
Abutilon incanum
Opuntis lindheimeri
Woollybucket bumelia
Rhus aromatica
Common mesquite (mast)
Prosopis glandulosa
Spreading sida
Sida filicaulis
Gray goldaster
Heterotheca canescens
V-A 4 Wildlife Management Handbook
Appendix I (continued)
Selected East Texas forage plants:
Alabama supplejack
Berchemia sp.
White ash
Fraxinus americana
Ilex vomitoria
Rubus sp.
Smilax sp.
Kentucky virburnum
Virburnum molle
Georgia holley
Ilex longipes
Honey locust
Gleditsia sp.
Selected Edwards Plateau forage plants:
Texas oak (Spanish oak)
Quercus texana
Q. virginiana
Post oak
Q. stellata
White shin oak
Q. breviloba
Woollybucket bumella
Bumelia lanuginosa
Celtis sp.
Smilax sp.
Ulmus sp.
Flameleaf sumac
Rhus copallina
Grape sp.
Vitis sp.
Velvet bundleflower
Desmanthus velutinus
Knotweed leafflower
Phyllanthus polygonoides
Prickly lettuce
Lactuca serriola
Southwest bedstraw
Galium sp.
Mat euphorbia
Euphorbia serpens
Four-o'clock sp.
Mirabilis sp.
RE: will deer eat grass
absolutley. In fact during spring turkey season here in oklahoma I say two does eat plain ol' grass right in front of me for about thirty minutes
RE: will deer eat grass
Sorry Kybuckhunter, this is one of the few times I don't need a handbook. At least up here in New England, I've been watching deer feed in hay fields for more then 35 years.
RE: will deer eat grass
[align=left]Deer Digestion[/align][align=left]Studies of deer digestion by Short indicate that deer[/align][align=left]do not digest coarse fibered plants as readily as low[/align][align=left]fibered plants. In addition, it has also been determined that[/align][align=left]browse plants high in oil content inhibit the "fermentation"[/align][align=left]process in deer. Domestic livestock are more efficient in[/align][align=left]digestion of these plants. It is not unusual to find deer[/align][align=left]which have "starved" with a paunch full of grass.[/align]
RE: will deer eat grass
I think the point that is trying to be made is,,deer eat some types of grass. Clover, alfalfa, rye, oats, wild flowers, forbes,etc... JUST TO NAME A FEW. I'm sure that on occassion that deer might eat just plain old lawn grass. But all in all deer deer don't eat plain old lawn grass, as a main food source.
People on here saying they saw deer in a field eating grass, probably saw a deer in a field eating clover, forbes, alfalfa or one of the many TYPES of grass.
Thisthread is just some people confusing "plain old lawn grass" for one of the many types eaten by deer.
Some are labeling all types of grasses as just grass while others are noting that there are certain types eaten and are seperating lawn grass from oats, clover, wildflowers.
When you shell out big bucks for a bag of seeds for a food plot you are not buying lawn grass. You are buy the types that are desired by deer.
I think the original intent of this thread was ask by a beginner hunter asking if deer eat gras that grows between corn fields and woods. Perhaps he was thinking of putting up a stand there or something. Then everyone was posting that, yes, deer eat grass.
The thread then got turned around.
It is true that deer are browsers not grazers. While they eat certain types of grass they aren't partial to lawn grass. They may eat it but they prefer many, many, many other types of plants over it.
RE: will deer eat grass
Right on,WW7!
RE: will deer eat grass
I have 40 acres of Argentine Bahia, Wild Persimmons, Crab Apples, Over 100 Live Oak Trees (tons of acorns), Wild Black Berries, Wild Asparagus, Wild Pears and God knows what else!
All the hugeHibiscus Plants around the houseget their leafs eaten off, can't keep Rose Bushes around house. Here is a fat rump Doe and her two twins that I chased from my yard into the pasture. This is about 800 ft from my front door.They appear to be eating grass, but are picking on forbes in the grass.
I have Bucks, Does and fawns all around my house and many more on the property.
RE: will deer eat grass
When I read this I thought, "this must be a trick question."
Yes, deer will eat grasses of many types. I will see countless deer often when I drive, especially at night on relatively quiet country roads where there is fresh green grass, some clover and assorted other vegetation.
Of course, they eat all sort of other browse like young sappling shoots, acorns, apples, cedar bows, grainsand some pine tree ends (white pine) to name a few.
I have no idea why anyone wouldn't think an animal that browses on all sorts of other vegetation would eat tender green grasses.
RE: will deer eat grass
deerhunt1...i think all browsers can and do
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text:
An architecture student will host a metal casting workshop to celebrate the Tottenham's industrial history.
Alexander Sarafian, who studies at the Cass School of Architecture, in Holloway, organised the event at the Holy Trinity Church, in Philip Lane, Tottenham.
It will take place on Saturday and Sunday and is open to anybody interested in the areas industrial history and to those who would like to learn about the process of casting.
People who wish to attend have been asked to bring their old aluminium cans, which will then be melted down and cast into memorabilia on-site.
The workshop will run from 10am to 5pm.


text:
Tennis / Son of Ramle Market Vendor Isn't Your Usual Tennis Prodigy
Yshai Oliel, who won the Junior Orange Bowl tourney this week, gets quiet support from parents, not money and pressure.
Four years ago, tennis coach Jan Pochter took four of the young players he had been nurturing at the Ramle Tennis Center to see veteran coach Schlomo...
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text:
A poster competition has been launched by West Sussex County Council. The Youth Support and Development Service is asking young people to design a poster using the slogan 'we're better without bullying'. The slogan was the theme for Anti-Bullying Week 2012, which ran from November 19 to 23.
Young people can enter individually or as a school or youth centre in two age categories: seven to 12 years old and 13 to 16 years old. High street shopping vouchers worth £20 will be presented to the best poster in each age group, with the overall winning poster being produced and used across the county to promote anti-bullying.
Closing date is December 14 at 7pm. Send entries to firstname.lastname@example.com or post them to Karon Chamberlain, Oriel Lodge, County Hall, West Street, Chichester, PO19 1RF. Find out more at www.yourspacewestsussex.co.uk