Climate mitigation measures in Danish pig production
The aim is ambitious: 50% reduction in CO2e emissions from pig production by 2023.
Danish pigs currently account for 14 per cent of the total CO2 emissions from the agriculture sector. New technological measures need to be adopted on Danish pig farms.
In this series of articles on climate mitigation measures, we examine current initiatives, research and technologies in Danish pig production aimed at meeting the carbon footprint reduction target. This edition focuses on slurry cooling.
Slurry cooling
Slurry cooling helps to reduce ammonia emissions.
Several systems have been tested within this area. Tests were carried out in Denmark in the 1990s whereby cooling pipes were placed at the bottom of the slurry pit in a finisher unit with a fully slatted floor. However, the study showed that the temperature of the slurry increased throughout the slurry which reduced the effect of slurry cooling on ammonia emissions. In this study, the reduction was found to be 10 per cent, with a cooling rate of 10 W/m2.
In the Netherlands, slurry is cooled through the surface by using cooling fins that float on the surface, which is why slurry cooling in the Netherlands is approved for higher efficiency. However, the approved reduction in the Netherlands involves slurry cooling combined with a minimum of 40 per cent solid flooring in the pen combined with cast iron slats in the manure area, resulting in a total reduction of 70 per cent in ammonia emissions.
Slurry cooling using embedded cooling pipes has been tested in Sweden where it was shown that the method could cool the bottom of the slurry pit as well as the slurry. This method is now the most widespread in Denmark as it ensures the effective operation of the slurry system.
On the basis of the above studies, slurry cooling has been included on the Danish Environmental Protection Agency’s Technology List.
Slurry cooling connected to a heat pump is an environmental technology that can reduce ammonia emissions from the housing unit while recycling energy to generate heat for the farm. The heat can, for example, be used in housing units where heating is required as well other heating needs elsewhere. This technology is therefore interesting, particularly in connection with renovation projects or new builds.
Read more about climate migitation measures: