Hydraulic Settling of Flushed Swine Manure A Case Study

ADAPTION of flushed manure management systems for modern swine production facilities has reduced labor managment problems, but in doing so has created new problems. Typical problems may include odors from lagoons or other liquid storage structures, and the managment of labor and equipment involved with recycling flush water or field applications. Recycling is important because water is limited in many areas and flush water must be reused (Graves et al., 1971; Fischer et al., 1975). The putrified material, when applied to land, can cause odor problems to the surrounding environment. In addition, conventional pumping and irrigation equipment often plug, which results in inefficiencies. Some relief from these problems can be accomplished by separating the liquids from the solids in the flushed manure (Gilbertson and Nienaber, 1979). Mechanical separators are available for separating solids and liquids in agricultural, municipal, and industrial waste (Glerum et al., 1971; Hegg et al., 1981; Ngoddy et al., 1971). The available equipment, however, is not always economically feasible. In addition, design and operational characteristics required to develop equipment suitable for these facilities may be limited. The objective of this study was to develop design criteria and performance characteristics for continuous separation of settleable solids (SS) from flushed swine manure.