Drainage Properties and Ammonia Emissions in Slatted Floor Systems for Animal Buildings

Abstract

Drainage properties of and ammonia emissions from slatted floors and drainage channels were investigated using a laboratory arrangement development for the purpose. The arrangement consists of a steel-framed box with two levels in order to simulate different slatted floor systems. The slatted floor under test is laid on the top level and manure is dropped on to it from various heights. The lower level consists of a drainage channel, the top of which is covered by a lid perforated with holes of different shapes.Drainage experiments on slatted floors for cows with slits from 30 to 45 mm wide showed an average total drainage value for faeces and urine of 72% and an average urine drainage value of 82%. Drainage experiments on slatted floors for pigs showed results varying between 38 and 46% for total drainage depending on different drainage arrangements. The best drainage capacity was obtained when the drainage channel cover had holes giving a large drainage area.The ammonia experiments on slatted floors for cows with 2 and 30 mm spacing showed an accummulated ammonia emission of about 8 and 3 g respectively, during the 20 h testing period. On slatted floors for fattening pigs, the accumulated ammonia emission was calculated to be about 2 g during the 20 h testing period. These ammonia emission results are related to the mass quantities and the nitrogen contents of faeces and urine, which normally are dropped to slatted floor surfaces in animal buildings.