Effect of the application of a heat pump to accumulate heat generated during deep litter fermentation on limiting ammonia emission in pig breeding

摘要

It was assumed that collection of thermal energy of fermenting manure by a heat pump would allow to use it for heating purposes and reduce the intensity of exothermic processes, which should decrease ammonia emission. The aim of the paper was to confirm experimentally the assumptions made and to determine the parameters of the heat recuperated and ammonia produced. The studies on ammonia emission in the function of ambient temperature in pig breeding on the so-called deep litter were carried out ina research room This room is equipped with special facilities for constant control of the air flow and for a few days' registration of gaseous contamination, as well as some microclimate parameters. The studies on the differences in ammonia emission were performed in an experimental room, where a heat exchanger was placed in a concrete floor, and in a control room, both located in a pig fattening house. The studies were carried out from October 1997 to March 1998. To perform the studies in the experimental and control rooms, two pens were used. The animal population was 80 pigs per pen. In the experimental pens, a polyethylene piping in the form of a tube served as a heat exchanger. It was placed in a concrete floor. A CETUS 14 heat pump was also applied. The following parameters were recorded during the research: top and bottom source temperature, litter temperature, floor temperature, air temperature and humidity in the building (in the pigsty and offices) and outside, ammonia concentration at three measuring points, and electric energy use. The following devices were used, among others, in the course of the studies: a HANNA INSTRUMENTS HI91610 hytherograph and a TRIPLE PLUS gas analyzer made by Crown. Those instruments are capable of rememberingthe measurement results, which are sent to the PC memory and then analyzed and processed.