Dewatering of phosphorus extracted from liquid swine waste.
Phosphorus (P) recovery from liquid swine manure is an attractive technology when on-farm application of liquid swine manure is not an option. We developed a technology that enables separation of this P, but its high moisture content makes transportation difficult. In this work, we investigated dewatering procedures to concentrate the P product. Sludge rich in calcium phosphate (> 20% P2O5) was obtained using a field prototype, and it was further dewatered using a combination of polymer treatment and filter bags. Anionic polyacrylamide polymer treatment (> or = 20 mg/L) was effective to flocculate the P-rich sludge, which enhanced filtration and dewatering. Without polymer, filtration was incomplete due to clogging of filters. Non-woven polypropylene and monofilament filter bag fabrics with mesh size < or = 200 microm retained > 99% of suspended solids and total P. Solids content dramatically increased from about 1.5% to > 90%. These dewatered solids can be transported more economically off the farm for use as a valuable fertilizer material.
Szögi
Ariel A
AA
USDA-ARS, Coastal Plains Soil, Water and Plant Research Center, 2611 W. Lucas Street, SC 29501, United States. szogi@florence.ars.usda.gov
Vanotti
Matias B
MB
Hunt
Patrick G
PG
D000180:Acrylic Resins; D000818:Animals; D000838:Anions; D005374:Filtration / Q000379:methods; D007700:Kinetics; D010758:Phosphorus / Q000302:isolation & purification*; D012722:Sewage / Q000737:chemistry*; D013552:Swine; D018505:Waste Management / Q000379:methods*; D000099166:Polyacrylamides
D000180:Acrylic Resins; D000838:Anions; D010758:Phosphorus; D012722:Sewage; D000099166:Polyacrylamides