Remonal Of Ammonia And Phosphorus From Sludge Fermentation Liquid And Utilization Of Internal Carbon Source

The sludge in sewage treatment plant has become an inevitable problem in the process of solving environmental pollution problems.The excess sludge treatment has become a hot spot in sludge reclamation and reuse area because that the sludge contains a large amount of organic such as nitrogen,phosphorus,etc which can be used for resource utilization and produces high concentration of ammonia phosphorus which is an important component of struvular stone during the alkaline anaerobic fermentation process.In the process of sewage treatment plant running,there always was a lack of carbon sources while the volatile acid produced in sludge fermentation process could be a supplementary to solve this problem which has an important practical significance.The volatile acid(VFAs)produced can be used as a supplementary carbon source to solve the problem of carbon deficiency in the operation of the WWTP,which has an important practical application significance.According to the previous study,this paper extracts the supernatant of alkaline anaerobic fermentation sludge and introduces the chemical precipitation and electrolytic method to remove the ammonia phosphorus substance in it.The high COD supernatant after treatment was used as the influent carbon source in SBR system,and compares with the water distribution system with sodium acetate as the carbon source by which to verify the feasibility of biological nitrogen and phosphorus removal system by adding carbon source.The results were showed as follows:(1)The fermentation sludge treat by the chemical precipitation method,the rate of ammonia phosphorus removal is so rapid that the reaction can reach the end within 1min.The optimum process effect of ammonia removal and COD retention is determined by exploring the different dosing ratios.Finally,the conclusion was drawn as follows: the remove of cmmonia nitrogen is more than 80% and the phosphorus removal over 90%,while 78% COD is preserved under P / N = 1.13,Mg / P = 1.00.The electrolysis time results cmmonia nitrogen to minimum can reduce by increasing the current density when the fermentation sludge under the impacts of electrolytic magnesium rods.There is a economical ammonia removal when the current is 70 mA and the reaction time is 3h by controlling the different time,the current and other factors.(2)Compared with the chemical reaction and electrolysis reaction,it is concluded that the chemical reaction is superior to the electrolysis reaction in terms of ammonia removal rate,reaction rate,effluent ammonia nitrogen concentration and COD retention rate.(3)In the SBR reaction system,it is found that the COD utilization rate of the distribution water source is close to 90%,the removal rate of ammonia nitrogen is mostly above 90% while the removal rate of phosphorus is below 50% The carbon source in the fermentation broth is rich,and the dissolved sugar and protein can be used as carbon source.the utilization rate of sugar was 55%,protein 65% and total COD higher than 75% as the removal rate of ammonia nitrogen is more than 80% and the removal rate of phosphorus is close to 75%.It is feasible to utilize the anaerobic fermentation sludge as a substitute carbon source to reduce the nitrogen and phosphorus jin municipal wastewater.The sugar and protein of the fermentation broth can promote the effect of nitrogen and phosphorus removal.