▁increase ▁in ▁rec y cling ▁rates ▁has ▁been ▁seen ▁in ▁the ▁areas ▁where ▁these ▁plants ▁exist . ▁In ▁the ▁United ▁States , ▁there ▁are ▁over ▁ 3 0 0 ▁materials ▁recovery ▁facilities . ▁ ▁Initial ly , ▁the ▁comm ing led ▁rec y cl ates ▁are ▁removed ▁from ▁the ▁collection ▁vehicle ▁and ▁placed ▁on ▁a ▁convey or ▁bel t ▁spread ▁out ▁in ▁a ▁single ▁layer . ▁Lar ge ▁pieces ▁of ▁cor rug ated ▁fi ber board ▁and ▁pl astic ▁b ags ▁are ▁removed ▁by ▁hand ▁at ▁this ▁stage , ▁as ▁they ▁can ▁cause ▁later ▁mach in ery ▁to ▁jam . ▁ ▁Next , ▁autom ated ▁mach in ery ▁such ▁as ▁disk ▁screens ▁and ▁air ▁class ifiers ▁separate ▁the ▁rec y cl ates ▁by ▁weight , ▁splitting ▁l ighter ▁paper ▁and ▁pl astic ▁from ▁heav ier ▁glass ▁and ▁metal . ▁Card board ▁is ▁removed ▁from ▁the ▁mixed ▁paper ▁and ▁the ▁most ▁common ▁types ▁of ▁pl astic , ▁P ET ▁( # 1 ) ▁and ▁HD PE ▁( # 2 ), ▁are ▁collected . ▁This ▁separation ▁is ▁usually ▁done ▁by ▁hand ▁but ▁has ▁become ▁autom ated ▁in ▁some ▁sorting ▁cent ers : ▁a ▁spect ro scop ic ▁sc anner ▁is ▁used ▁to ▁differenti ate ▁between ▁different ▁types ▁of ▁paper ▁and ▁pl astic ▁based ▁on ▁the ▁absor bed ▁w avel ength s , ▁and ▁subsequently ▁di vert ▁each ▁material ▁into ▁the ▁proper ▁collection ▁channel . ▁ ▁Str ong ▁magnet s ▁are ▁used ▁to ▁separate ▁out ▁f err ous ▁met als , ▁such ▁as ▁iron , ▁steel