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.

[1]  B. F. Severin,et al.  Laboratory simulation of belt press dewatering: Application of the Darcy equation to gravity drainage , 1996 .

[2]  F. Haywood.  Handling liquids and solids on hog farms , 1997 .

[3]  P. Walker,et al.  Solids, organic load and nutrient concentration reductions in swine waste slurry using a polyacrylamide (PAM)-aided solids flocculation treatment. , 2003, Bioresource technology.

[4]  P. Ndegwa,et al.  Effects of Solid Levels and Chemical Additives on Removal of Solids and Phosphorus in Swine Manure , 2001 .

[5]  Charles R. Rhyner,et al.  Waste Management and Resource Recovery , 1995 .

[6]  J. Burkholder,et al.  Impacts to a coastal river and estuary from rupture of a large swine waste holding lagoon , 1997 .

[7]  D. M. Sievers,et al.  Treatment of Dilute Manure Wastewaters by Chemical Coagulation , 1994 .

[8]  B. Urlings,et al.  Utilization of fermented flocculated poultry sludge as a feed constituent for pigs. , 1995, Poultry science.

[9]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[10]  J. A. Merkel,et al.  Managing livestock wastes , 1981 .

[11]  P. Walker,et al.  Bacterial concentration reduction in swine waste amended livestock feed using a single-screw dry-extrusion process , 2000 .

[12]  Patrick G. Hunt,et al.  Solids and nutrient removal from flushed swine manure using polyacrylamides , 1999 .

[13]  W. Bennett.  Nutrient Deficiencies & Toxicities in Crop Plants , 1993 .

[14]  W. Ritter,et al.  Impact of animal waste lagoons on ground-water quality. , 1990 .

[15]  E. Mckyes,et al.  Performance of a continuous belt microscreening unit for solid liquid separation of swine waste , 1988 .

[16]  Joseph A. Salvato,et al.  Environmental engineering and sanitation , 1972 .