Research On The Treatment Of Ammonia Nitrogen In Vegetable Biogas Liquid Based On Aerobic Baffle Device

The annual output of livestock and poultry manure and vegetable waste in my country increases year by year,which makes agricultural solid waste become the main source of current pollution.Anaerobic digestion technology can convert agricultural solid waste into organic fertilizer and clean energy,but with the development of biogas projects With the expansion and scale,a large amount of high ammonia nitrogen biogas slurry is becoming an important part of China’s sewage sources,and the problem of discharge treatment needs to be properly solved.In this paper,in view of the problem of biogas slurry discharge after vegetable waste in Yunnan Province is treated by CSTR reactor,a combined process is selected to treat biogas slurry wastewater and recover nitrogen,so as to control the effluent water quality within the standard discharge range.For the characteristics of high content of colloidal suspended solids and ammonia nitrogen in vegetable biogas slurry,and large processing capacity,the project first tried to remove a large amount of suspended solids in the biogas slurry through a filtration unit based on aerobic devices,and then used the sedimentation and adsorption process.Combined to treat ammonia nitrogen in biogas slurry wastewater.Firstly,in the filtration unit,according to the isothermal adsorption and desorption rate results under the static condition of the material,the low-adsorption fillers for ammonia nitrogen were screened,and then the depth of the filler in the aerobic baffle trench and the operation time were investigated under dynamic conditions to remove suspended solids in the biogas slurry.The effect and the influence of ammonia nitrogen concentration,the suspension of vegetable biogas slurry was initially controlled within a reasonable range.Secondly,in the precipitation experiment,through static treatment,the optimal parameter ratio of ammonia nitrogen removal rate was determined by reaction time,reaction p H,phosphorus-nitrogen ratio,and magnesium-nitrogen ratio,and the response surface test was used to determine the dynamic test parameter setting.Then,the adsorption process was used to treat biogas slurry wastewater with low ammonia nitrogen concentration.Ammonia nitrogen adsorption and desorption performance,determine the treatment of biogas slurry wastewater filler.Finally,the above filtration,precipitation and adsorption units were combined into an aerobic baffle device to test the effect.The results of the filtration process showed that the removal of SS in the biogas slurry was higher at 18 h under the conditions of medium and high packing depths,which were 8.1 and 8.2 g/L,respectively,and the removal rates were 86.1 and 88.7%,respectively.The precipitation process had the highest removal rate of ammonia nitrogen.The adsorption process results show that the unit equilibrium adsorption capacity of broken lignite activated carbon is the largest,which is about 26.75 mg/g,and the desorption capacity is 17.31 mg/g;the combined process shows that in When running for 24 h,the residual ammonia nitrogen amount was about 10.4 mg/L,and the removal rate was about 98.5%.