Time to get on top of ammonia emissions

The need to control ammonia emissions from poultry units is going to present the UK industry with some weighty challenges and hefty bills, producers have been warned.

Addressing the East Midlands poultry discussion group, Steve Smith, a meteorologist working for ADAS, said the most significant contribution that the industry could make was to put a brake on the output of ammonia seeping out from poultry units.

Air “scrubbing” (filtering) was the most effective method, he said, but also the most expensive. Farmers should also consider reducing the protein levels of rations and treating litter and manure with bisulphate to reduce the ammonia level.

The Environment Agency had emerged as a hard taskmaster in enforcing ammonia limits, Mr Smith warned. “The targets are tough and many existing installations may find their houses exceed permitted levels.”

Producers planning to expand units would have to upgrade to the best available techniques, he added, and this was guaranteed to inflate the cost.

The crux of the matter was the level of total ammoniacal nitrogen (TAN) in poultry litter, which was dependent on the temperature, moisture content, alkalinity and the number of times the litter was disturbed. “The higher the temperature, the wetter the litter and the higher the ph, the greater the quantity of ammonia,” said Mr Smith.