Experimental Study On The Technological Process For The Production Of High-quality Anaerobic Fermentation Slurry From Swine Manure

The animal manure that is one of the chief pollution resources from livestock and poultry farms at present, as well as unreasonable utilization of chemical fertilizers and pesticides, result in serious environmental pollution and jeopardize the health of the human being.Anaerobic fermentation system is able to deal with animal wastes effectively and ecologically; therefore, it is studied and made use widely at home and abroad.Anaerobic fermentation slurry is the remains left in reactors after anaerobic microbes decompose organic wastes under the condition of no oxygen. Anaerobic fermentation slurry, which is considered as a high quality organic fertilizer and broard-spctrum biological pesticide, can be used to promote the growth of plants and to prevent them from pests and diseases. Therefore, the manufacture of anaerobic fermentation slurry not only utilizes animal wastes but also enhances the economic benefit of anaerobic fermentation technique, having latent commercial value.In this research, anaerobic fermentation slurry is produced in BIOF-2010 Biological Fermentation Tank and fermentation conditions are controlled automatically. The contents of total nitrogen, ammonia nitrogen, total phosphorus and soluble phosphorus are measured every day to determine how the changes of fermentation conditions affect the quality of anaerobic fermentation slurry. Then, according to the above experimental results, an orthogonal experiment is designed to find the optimum combination of temperature, concentration and fermentation time for the production of anaerobic fermentation slurry. Several conclusions are drawn by variance analysis of the orthogonal experiment. Concentration is the most notable factors influencing the content of ammonia nitrogen in anaerobic fermentation slurry; when fermentation time is 5 days, temperature is 30℃ and concentration is 3.7%, the content of ammonia nitrogen is highest. Fermentation time is the most importantcontrol parameter to affect the content of soluble phosphorus in anaerobic fermentation slurry, followed by temperature; when fermentation time is 4 days, temperature is 55℃ and concentration is 1.85% , the content of soluble phosphorus is highest. Furthermore, the variance analysis is also showed that if the contents of ammonia nitrogen and soluble phosphorus are considered synthetically, the optimal running conditional combination is that the temperature is 55℃, the concentration is 1.85% and the fermentation time is 4 days manufacturing high quality anaerobic fermentation slurry.The technological process for the production of the high quality anaerobic fermentation slurry instead of biogas is given in this thesis, expanding a new road to handle animal wastes ecologically and to manufacture agricultural products safely.