Ammonia evaporation is negatively correlated with the temperature. Cooling the slurry in the slurry channels with an effect of 24 W/m2 slurry channel has scientifically been verified to give 31% reduced ammonia evaporation. The effect on evaporation depends on the housing system and the cooling effect.
Slurry cooling is established by embedment of plastic (PEL) tubing at the bottom of slurry or manure channels in the stables. The hoses are typically laid with a distance of 35-40 cm. In stables with slurry system, the cooling hoses are alternatively laid directly on top of the channel bottom. The cooling tubes are connected to a heat pump. Liquid cooling is most relevant in pig herds wherein the recovered heat can be used for heating purposes, which typically is about herds with sows and piglets.