Separation of Liquid Pig Manure by Flocculation and Ion Exchange Part 2: Pilot-Scale System

Abstract This paper reports the function and working results from a pilot plant in which liquid pig manure was flocculated with Geko-bentonite. The supernatant was irrigated on agricultural land throughout the year, but in the wintertime, only after ion exchange of ammonium with Agrolith. Earlier laboratory experiments showed that it is possible to purify the liquid to exactly the concentration wanted, although higher purity costs more. Hence, it is possible to use the method according to the legislation of individual countries to spray or irrigate the liquid onto fields. The thicker slurry fraction must be stored and treated as ordinary liquid manure. In order to maintain ability for pumping, the treatment should be stopped at approximately 12% dry-matter content, which represents a concentration of the liquid manure to approximately one-quarter to one-third of the original volume.