Reduction of Methane Emissions from Manure

摘要

Slurry is the most common manure system in Dutch animal husbandry. Cost effective options to reduce methane emissions, without increasing emissions of ammonia and nitrous oxide, are covering the outdoor slurry storage, shortening the indoor storage time, frequent and complete removal of the slurry from the building, lowering the slurry temperature and filtration of the air from the livestock house and storage facility. Other, from a cost and management point of view less favorable, options are aeration, acidification, feed adjustments and controlled anaerobic digestion. In The Netherlands the average temperature of outdoor storage is less than 10.2°C, but the indoor storage for pig manure is around 17°C. Quick removal of slurry from the animal housing can reduce methane emissions by 66%. In addition, measurements showed a reduction of more than 50% of methane emissions for well covered outdoor storages with slurry at rest. Since most of the methane is produced in the livestock house it is evident that filtering the methane from the ventilation air can be an effective mitigation option. Air filters, which are still under development, can result in a reduction of up to 50% of the total methane emissions from livestock. Implementation of reduction options in agriculture are only possible if farmers are willing to co-operate. Additional income from emissions trading might be a stimulating option.