Title: Geotextile filtration performance for lagoon sludges and liquid animal manures dewatering Authors
|Chastain, John - CLEMSON UNIV, CLEMSON,SC|
|Moore, Kathy - CLEMSON UNIV, CLEMSON,SC|
Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 26, 2008
Publication Date: June 23, 2008
Repository URL: http://hdl.handle.net/10113/19615
Citation: Cantrell, K.B., Chastain, J.P., Moore, K.P. 2008. Geotextile filtration performance for lagoon sludges and liquid animal manures dewatering. Transactions of the ASABE 51(3):1067-1076. Interpretive Summary: Maintenance and control of the liquid levels in lagoons and storage ponds require removal of solids from the feed waste streams as well as periodic removal of the accumulated sludges. Geotextile filtration uses woven plastic mesh to retain a portion of the solids while reducing the volume of manure needing disposal. Experiments were performed to test geotextile filtration in dewatering: dairy lagoon sludge, swine lagoon sludge, fresh liquid swine manure, and fresh liquid dairy manure. Geotextile filtration was effective in treating dairy and swine lagoon sludge retaining significant portions of solids and reducing the volume of solids to one-fifth the total input volume. Geotextile filtration was ineffective in treating fresh swine manure since a significant volume of manure did not pass through the weave. Geotextile filtration of the fresh dairy manure retained almost half of the solids and reduced the solid's volume to less than 1% of the total volume.
Technical Abstract: Maintenance and control of liquid levels in anaerobic lagoons and storage ponds require liquid-solid separation as a pretreatment and periodic removal of accumulated sludges. Until local options become available, sludges can be contained, dewatered, and stored using geotextile filtration. We used a geotextile filtration testing method termed a hanging-bag test to treat dairy lagoon sludge, swine lagoon sludge, fresh liquid dairy manure, and fresh liquid swine manure. Hanging-bag performance was evaluated by:(1)determining solids and plant nutrient mass retention efficiencies (MRE);(2)quantifying the overall volume reduction; and (3)characterizing the dewatered manure. When bags underwent multiple fill-dewater cycles, the MRE-values for the various manures or sludges did not vary for many constituents. In fact, after three fill-dewater cycles, the overall MRE-values among the sludges were not significantly different. Geotextile filtration retained 87.8% of total solids (TS), 58.4% of total ammoniacal nitrogen (TAN), 87.0% of organic-N (Org-N), and 86.7% of total phosphorous (TP) and reduced the total influent volume to less than 18.5%. Relatively high MRE-values were calculated for liquid swine manure: 70.2% of TS, 65.1% of TAN, 69.9% of Org-N, and 75.8% of TP. However, the geotextile bag retained 60.3% of the total influent volume making geotextile filtration ineffective for primary liquid-solid separation. For fresh dairy manure (TS=0.71%), geotextile filtration reduced the total influent volume to less than 1%, concentrated the solids and nutrients in the dewatered material 16 to 21 times greater than the influent, and retained 47.3% of TS, 25.8% of TAN, 43.0% of Org-N, and 44.9% of TP making this an effective liquid-solid separation technique.