May 11, 2007

US scientist invents filter to absorb ammonia in chicken farms

A US scientist has found a way to filter the air in chicken coops to reduce ammonia, dust and pathogen levels entering the environment.

Philip Moore, who works in the Agricultural Research Service (ARS)'s Poultry Production and Product Safety Research Unit, has developed and patented a simple scrubber that cleans exhaust air from poultry houses and hog farms.

The scrubber releases a solution of aluminum sulfate, or alum, down a series of wooden slats so that ammonia, dust and pathogens is absorbed into it.

It can capture as much as 10 pounds of nitrogen in the form of ammonia a day. The captured nitrogen can then be applied as fertilizer.

Aluminum suphate is a proven ammonia and phosphorus absorber. It is currently used in US chicken farms but new technologies are still being explored.

Ammonia can be problematic in chicken farms, especially during the winter months when heat needs to be kept in the farms to keep costs down.

High ammonia concentrations causes health problems in birds and weaken their immunity to viruses. It also reduces growth rate, causes drops in egg production and can cause blindness.

In the environment, ammonia contributes to acid rain and algal blooms.