Apparatus for extraction Performance of commercial extraction equipment type HTU plate spacing between typical capacity /ft plates applications combined stage or stages treams efficiency ft3/ft2-h (% mixer-settler 75-100 Duo-Sol process 50-250 10-20 ammonia column extraction of salt from caustic soda packed 20-150 5-20 phene column recover perforated 10-200 1-20 6-24 30-70 furfural p column process agitated 50-100 2 80-100 12-24 pharmaceutica tower Is and organic chemicalsApparatus for extraction • Performance of commercial extraction equipment type Liquid capacity combined streams, ft3/ft2-h HTU /ft plate or stage efficiency (%) spacing between plates or stages, in. typical applications mixer-settler 75-100 Duo-Sol lube-oil process spray column 50-250 10-20 ammonia extraction of salt from caustic soda packed column 20-150 5-20 phenol recovery perforated -plate column 10-200 1-20 6-24 30-70 furfural lube-oil process agitated tower 50-100 1-2 80-100 12-24 pharmaceutica ls and organic chemicals