Freeze separation to remove nutrients from liquid swine manure

Thin-layered freezing was used in a pilot-scale field study for the treatment of liquid swine manure. It was found to be a viable mechanism for extracting a large volume of nutrients from liquid swine manure. More than 75% of the nutrients were recovered and concentrated to one-third the original volume. A significant volume of treated water was produced, which may be a valuable resource for use as recycle or irrigation water on farms. The thin-layered freezing process also removed the objectionable odour of the liquid swine manure.; The technical components of the pilot-scale field system and its operation were examined as a basis for developing a full-scale treatment system at intensive livestock operations. The capital cost for constructing a new system was {dollar}38/m 3 of manure treated compared to {dollar}25/m3 treated for retrofitting an existing dual earthen manure storage system. The annual operating costs were found to be {dollar}0.45/m3.