There is an enormous potential for growth in biogas in Uruguay. The country is not large, with a population of around 3.4 million, but the government is relatively stable, and the land is mostly verdant and productive. Meat and sheep farming in Uruguay occupies about 60% of the land. Most of the rest is used for when cattle breeding, and other farm activities such as dairy, forage, and rotation with crops such as rice. In other countries with a generally similar agriculture there has been success in installing and operating biogas facilities.
However, apart from some information on anaerobic digestion plants installed at some Uruguayan sewage works, for the disposal of sludge, in combination with biogas production, the seemed to be a lack of large biogas facilities in Uruguay.
To view this video on YouTube click this link to the biogas in Uruguay.
Regarding Municipal Solid Waste (MSW), 960 000 tons are generated per year in Uruguay. Landfill disposal is the only method used in Uruguay for MSW. From experimental data, landfill biogas generation is 20 m 3 / ton, and the energy that could be generated is 16.5 ktoe/year as biogas or 6.2 ktoe/year as electricity.
There are different sewage treatment systems in the country, aerobic and anaerobic systems and primary treatment. In all these cases the sludge generated must be treated. Considering the different options, the generated sludge was calculated. From this sewage works sludge, using anaerobic digestion, 1.86 ktoe/year could be obtained.
Slaughterhouses are one of the main industries in Uruguay. The methane production from paunch manure [partially digested feed] would be 2.3 ktoe/year.
This energy could provide 8% of the energy requirements of this industry.
At dairy farms, 51 000 tons of volatile solids per year are produced. The methane production from the solid digestion of would be 10.4 ktoe/year.
At the moment, 8% of the milk is pasteurised in the farms. About 40% of the energy that would be produced by anaerobic digestion of the residue could cover the energy requirements for the pasteurisation process.
An UASB reactor treating a malting plant effluent produces 300 m 3 /day of biogas (75% methane content).
Nevertheless the industry has installed a heater in order to take profit of the biogas generation.
In the case of MSW and sludge from sewage treatment, the main scope for biogas in Uruguay is to solve an environmental problem, with an extra benefit of energy production.
Press Release – 14 December 2017: The German biogas plant manufacturer WELTEC BIOPOWER recently signed the contract for a biogas plant extension of the milk powder producer, Estancias del Lago (EDL) in Uruguay.
From late 2018, the plant with its eight digesters will generate a rated thermal input of more than 6 Megawatt from cattle manure and fodder leftovers. The company will use the biogas for drying and steam generation purposes in the production process.
Founded in 2007, the agricultural company EDL now farms an area of about 37,000 ha. On this area, the South Americans grow maize, sorghum and soya as feed for their approximately 14,000 dairy cows. The company foundation was accompanied by the establishment of a huge site in Durazno, north of the capital Montevideo.
Apart from the cowsheds with milking centres and feed silos as well as the biogas plant, the premises now host a dairy and a grain mill. In Durazno, Estancias del Lago produces about 20,000 t of milk powder a year for export. Most of the milk solids are sold to China, Brazil and the Middle East.
In 2013, WELTEC had set up the first 800-kW biogas plant for EDL. Back then, expansion plans were already being considered. First, however, more cattle were needed. In the meantime, the number has therefore been stocked up from 8,000 to 14,000 cows. Now, 1,365 t of cattle manure plus 8.4 t of feed leftovers are available for the energy generation.
In view of the dimensions of the AD plant, the structural preparations already started in September 2017. In early 2018, WELTEC BIOPOWER will begin installing the six new 5,000-m³ stainless-steel digesters and the two 1,050-m³ pre-storage tanks for the slurry. With WELTEC’s custom-developed process control system CeMOS, the entire biogas plant will be fully automated from the end of 2018.
“As was the case back in 2013, the main reasons why the company opted for us were the high requirement profile and quality standard” explains Jens Albartus, Director of WELTEC BIOPOWER. For the plant expansion, the customer thus again wants to make use of stainless steel.
, explains Franz Cifuentes, Director of EDL.
Equipped with experience gained in the construction of large biomethane parks such as the one in Könnern, Germany, WELTEC is in charge of the entire building site management in Durazno, including the ancillary work.
Two gas boilers use part of the 30,000 standard m³ of biogas that is produced every day to generate heat for the biogas process. Most of the biogas is transferred to the close-by milk powder production facility via a pipeline. The biogas covers up to 35 percent of the heat required for the drying process. 100 percent of the steam needed is generated with biogas.
All operational units of the entire site are run in a very sustainable way. EDL contributes to this by growing its own fodder. The digestate from the biogas plant is used as fertiliser. Moreover, the cylce is closed by raising its own dairy cows and processing the milk on site. At the facilities located just 150 m from the cowsheds, the milk is processed to powder within four to eight hours. Another synergy has been established between EDL’s fuel production and other parts of the business: Apart from soya oil for the biodiesel plant, the oil mill yields press cake that is fed to the animals.
By means of plant extension, EDL can use its huge supply of raw material to establish a smart synergy between its agricultural and industrial operations.
This is exemplary for biogas in Uruguay, especially in view of the fact that this strategy is pursued throughout the country. Meanwhile, energy efficiency and renewable energies are the main drivers of the diversification of Uruguay’s energy mix.
The efforts which are encouraging for biogas in Uruguay, are promoted by progressive environmental laws.
In relation to the share of the primary energy, renewable energies already accounted for 57 percent in 2017. To further boost this share, the government in Montevideo has formulated the goal of using a growing portion of the agricultural leftovers for the generation of energy. The project Estancias del Lago is a fine example of how this can be achieved.
For more information about Weltec and other previous Weltec anaerobic digestion facility projects click here.