Source Reduction of Ammonia, Methane and Odor Emissions from Pig Houses

Samenvatting

In intensive livestock production areas, like parts of the Netherlands, there are big challenges to reduce emissions from the manure, especially ammonia (affects biodiversity), methane (greenhouse gas) and odor (nuisance). In a cooperation between research and the pig industry, different low emission designs for pig houses have been developed. A precondition was that these designs should also improve the indoor air quality by reducing emissions at their source. The designed systems reduced emissions mainly by one or more of the following measures: 1) frequent and complete removal of manure (with or without direct separation of urine and faeces); 2) dilution of manure; 3) reduction of the emitting surface; 4) clean floors. These low emission designs have been implemented on approx. 15 farms. So far complete emission measurements have been done at two farms with the following low emission design: - daily removal of manure by flushing with fresh manure, a small emitting area by reduced slatted floor areas and slanted walls in the manure channel, and dilution of a part of the manure. From the results it can be concluded that: - methane emission was reduced by over 90% by the daily flushing, with the remaining methane primarily produced by the pigs themselves (enteric methane); - ammonia emission was reduced by 45 to 65%, where higher reductions were achieved at low pen fouling levels; - odor emission was reduced by 10 to 40% and this decrease also appears to be associated with fouling in the pen.