Study On Ammonia Emission Factors In Concentrated Pig Farm

Ammonia (NH₃) and other air pollutants emission from concentrated animal feeding operations(CAFOs) are becoming more and more serious with the rapid development of livestock and poultryproduction in recent years, it has become the common index to assess the farm air quality in Europeand USA.The NH₃ emission factor is one of the effective methods for estimating ammonia emissionfrom CAFOs, assessing the air quality in and around CAFOs and evaluating efficiency of emissionreduction technologies. The researchers and public are paying more attention on the fields of NH₃emission factors, models and control technologies, and it has been hot in the livestock and poultryenvironmental engineering research field.1. Ammonia emission and impact factors of the four pig rooms with different floor systemswere studied, the NH₃ concentration and environmental parameters were monitored continually inthis research. The ammonia emission models of the four pig rooms were developed based on insideroom temperture, relative humidity, room vetilation rate and swine weight.The fully-slatted floor system room, F_NH3=-1.3837-0.0455T-0.0028H+0.0765W-1.6555V;The semi-slatted floor system room, F_NH3=-7.8555-0.0899T-0.0029H+0.2458W-42.5384V;The concrete floor system room, F_NH3=1.0497-0.0182T-0.0209H+0.1348W-35.9583V;The deep-litter system room, F_NH3=-2.6379+0.2368T-0.0281H+0.0176W+0.7640V;Where F_NH3-Ammonia concentration, ppm; T-Temperature,℃; H-Humidity, %; W-pigweight, kg; V-Ventilation rate, m³/s2. Mean daily ammonia emission factors of the four natural ventilation rooms withfully-slatted floor system, semi-slatted floor system, concrete floor system and deep-litter systemwere 9.87±5.77 g/(d·pig), 9.47±7.09 g/(d·pig), 11.23±4.23 g/(d·pig), 4.27±2.09 g/(d·pig) respectively.While, the emission factors of the four mechanical ventilation rooms were 7.10±7.14 g/(d·pig),4.79±6.16 g/(d·pig), 5.91±6.66 g/(d·pig) and 4.83±1.76 g/(d·pig), respectively.3. The ammonia emission characteristics, emission factors and impact factors during compost insummer were studied. The results showed that the daily ammonia concentrations were 2.04 to 14.67ppm, and average concentration during the compost was 7.2±4.17 ppm. Higher ammoniaconcentrations happened from third to twelfth days, which accounts for 60% of the total ammoniaemission. The ammonia emission factor of the compost was 3.26g/kg manure and the yearly nitrogenloss of the livestock and poultry manure in Zhejiang Province was estimated, and it was about 68.7million kilogram. The ammonia emission of composting was affected by turning, composting temperature andambient temperature. The ammonia emission rate was 2.5 to 12 times than normal when the compostwas turned and 65% of the ammonia volatilization during the day time (8:00AM to 20:00PM), 33%of the total ammonia emitted during the period of high temperature time (13:00PM to 17:00PM). Itwas found that ammonia emission affected the odor emission.4. Ammonia emission factors in extensive pig farms were studied. The results of the field andlaboratorial experiments were comparable. The emission factors of the fattening, weaning, farrowingpig rooms were 6.6 -7.1 g/(d·pig), 1.0-2.2 g/(d·pig), 12.5-17.3 g/(d·pig), respectively, and the boarroom was 35.2 g/(d·pig).It was primary research of the ammonia emission factors in China. The fingdings will providethe theoretical and technological base to the research of measuring and controlling the air pollutantsemission from CAFOs, the assessment of the animal buildings air quality impacted on human andanimal health, the research of low NH3 emission housings and slurry management technologies forChinese swine operation characteristics.