||There are many livestock farms and composting fields in Taiwan. In these farms and fields, odorous compounds such as ammonia, skatole, volatile organic acids, dimethyl sulfide, and low molecule weight aldehydes are emitted from animal bans or waste (excreta) treatment units. The emitted odorous air may cause olfactory nuisance to the nearby residents. In the present study, tests were performed for eliminating these odorous compounds by spraying the emitted air with aqueous solution containing hypochlorous acid or with water and ozone. The simulated odorous air was generated by passing air through a vessel containing wetted animal (pig or chicken) excreta.|
Experimental results indicate that spraying water containing hypochlorous acid with doses of 10 and 50 mg effective chlorine per cubic meter of gas could be effective for the removal of pig- and chicken-manure odor, respectively. Spraying water with ozone doses of 0.1-0.2 mg/m3 gas could effectively remove pig-manure odor. However, 5-10 mg/m3 ozone were required for the chicken-manure odor removal.
Estimation results indicate that it requires around 3 kg sodium hypochlorite solution (containing 12% effective chlorine) per hour for the removal of odorous air emitted from a field of 1,000 pigs. Application of spraying ozone and water to a field with 10,000 chickens, it requires NT$100,000 for the ozone generator and an electricity cost of NT$1.08 per hour for the ozone generation.