Study On The Phosphorus And Nitrogen Removal Of Sewage By Calcium And Magnesium Composite Method And ZSM-5 Adsorption Method

In recent years,National emissions of pollutants have strict requirements to enterprises,especially for waste water discharge of sewage treatment plant.Dongying sewage treatment plant adopts advanced A/A/O process for sewage treatment,and the content of TP,TN and NH₃-N is still high.In this paper,the following tasks are carried out in the following tasks:first,the solution to the treatment of sludge disposese is proposed for the high nitrogen and phosphorus content.Secondly,chemical precipitation method was used to combine calcium salt with magnesium salt and control its influencing factors to carry out static and dynamic tests,and remove TP,TN and NH₃-N indexes.Finally,ZSM-5 molecular sieves were used to adsorb NH₃-N in wastewater,and the pull-forming and regeneration of powder molecular sieve were studied.?1?This paper has taken a process course to adjust the way that nitrogen phosphorus is in the process,and it analyzes the water quality of the work,and the results are as follows:it's a1-5 mg/L,and TN is 15-35 mg/L,and the NH₃-N is 6-35 mg/L,and the nitrogen levels are far above the national standard.?2?In this paper,the chemical precipitation method was used to remove phosphorus and nitrogen from the sludge treatment filtrate,and the optimal technological conditions were obtained by comparing it with the existing agents in the sewage plant.It was found that in the static test,NaOH was 150 mg/L?pH value was 9.2?,MgCl₂ was 60 mg/L,CaCl₂ was 40 mg/L,and the optimal NH₃-N removal rate was 25%.In the dynamic test,it was determined that NaOH was 105 mg/L?pH value was 9.2?,MgCl₂ was 48 mg/L,CaCl₂ was 24 mg/L was the best ratio,and TP removal rate reached 90%,andTN,NH₃-N removal rate reached 30%.It was found that the cost of calcium and magnesium compound method was 0.074 yuan/m³lower than that of phosphorus removal agent,which highlighted the advantages of low cost and high efficiency of calcium and magnesium formula.This paper aiming at the problem of chemical precipitation denitrification falling below,puts forward the ZSM-5 molecular sieve adsorption method of ammonia nitrogen wastewater treatment and explores the factors affecting the adsorption of optimum adsorption conditions as follows:At room temperature,dosage of molecular sieves for 1 g,pH value of 8,mixing30min,dealing with 50 ml initial concentration of 50 mg/L of ammonia nitrogen wastewater,ammonia nitrogen removal rate was 86.6%,and the residual ammonia nitrogen concentration of 4.2 mg/L is lower than the national level A discharge standard 5 mg/L.The study on the mechanism of ZSM-5 molecular sieve adsorption ammonia nitrogen found that the process of ZSM-5 adsorption ammonia nitrogen conforms to the second-order kinetics model.The Langmuir equation conforms to the adsorption behavior of molecular sieve to ammonia nitrogen.The increase of temperature can promote the adsorption process,indicating that the adsorption process is spontaneous endothermic.Considering the molecular sieve powder,it is not conducive to recycling and is explored the optimum process.Conditions of molecular sieve powder forming are as follows:When ZSM-5 is 50 g,adding sesbania powder 1.8 g and1.8 g hydrochloride,and thin diaspore is 15g,mixing with 20 g water,and squeeze in shape.The optimal regeneration condition of ZSM-5 as follows:when the mixed solution of 0.2%NaOH and 0.2%NaCl was used as the reagent for desorption for 60 min,the regeneration effect was appropriate.