Comparison of a static gravity screen-roll press combination separator to a PAM-assisted gravity belt thickener system for swine waste slurry solids separation.
Liquid effluent resulting from solids separation from raw swine slurry (RS) using a static gravity screen-roll press separator (SE) and a polyacrylamide (PAM) flocculant-assisted gravity belt thickener system (BE1 and 2, with BE2 designating an added belt thickening of SE) were compared. Effluent pH was 7.6-7.7. Dissolved oxygen was less than 0.01 mg/l in RS and SE and 0.50 mg/l in BE1 and 2. Solids dry weight and total phosphorus concentrations were reduced significantly (p0.05) in SE (17-27%) and in BE1 and 2 (92-96%), relative to RS. Phosphorus concentration reductions were higher than those previously found. Settleable and suspended solids, total nitrogen and chemical oxygen demand were significantly reduced in BE1 and 2 (63-99%). No significant differences (p>0.05) were found between BE1 and 2. Results indicated that the gravity belt thickener system was more efficient at solids separation than the screen-roll press system.
Walker
Paul
P
Department of Agriculture, College of Applied Science and Technology, Illinois State University, Normal, IL 61790, USA. pwalker@ilstu.edu
Kelley
Tim
T
D000180:Acrylic Resins; D000818:Animals; D005427:Flocculation; D006112:Gravitation; D006863:Hydrogen-Ion Concentration; D008372:Manure; D010100:Oxygen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D013552:Swine; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods*; D000099166:Polyacrylamides
D000180:Acrylic Resins; D008372:Manure; D010100:Oxygen; D010758:Phosphorus; D000099166:Polyacrylamides