Study On Treatment Efficiency Of Micro-polluted Groundwater By Twostage Biofiltering Process

The problem of micro-pollution of groundwater is common in China,and it is difficult to guarantee the safety of water supply when the conventional groundwater purification process is compound pollution caused by natural organic matter,ammonia nitrogen,iron and manganese.A groundwater plant water supply scale of 50,000 tons/day,is the city’s main water supply.Due to improper location of water wells and poor water quality,the existing water treatment plant is difficult to protect water quality and safety.Especially in winter,the problem of poor water quality is more prominent,in order to ensure that the water quality of drinking water to meet the drinking water standards,an urgent need for an efficient and economical treatment process to solve the water quality problems faced by non-compliance.This study has important theoretical significance and practical application value for the determination of water purification engineering.In order to find out the water quality of the water plant and the water quality of the plant,the characteristics of the water quality of the water source in the winter of 2015 were investigated,the water quality of the factory and the problems existing in the existing process of the water plant were investigated.Characteristics and the problems existing in the existing process of the water plant,the pilot test platform was established.Through the pilot test device,the changes of the conventional water quality indexes of the effluent in different pilot units were studied,and the treatment efficiency of each pilot test process was explored;Determine the factors affecting the operation of the pilot process.The results show that the water quality of source water is not fluctuant,and the contents of iron and manganese in source water are respectively increased by 0.7mg/L and 0.3mg/L respectively after the opening of Well # 1 in winter.The organic pollutants in the source water were mainly fulvic acid-like substances,and some humic substances were also present in the water.After stable operation of the pilot plant,the bio-fortified and non-bio-fortified test groups were compared and analyzed.The effluent quality of the non-bio-fortified group was lower than that of the non-bio-fortified group.The effluent of the non-bio-fortified group was 0.15~0.3mg/L lower than that of the non-bio-fortification process,and the ability of controlling the permanganate index and ammonia nitrogen was 0.15~0.3mg/L and 0.2~0.3 mg/L.The optimal pilot process was determined as follows: bio-fortified primary filter(anthracite + manganese sand)+ aeration column + bio-enhanced secondary filter(activated charcoal + anthracite).The preferred pilot process was compared with the existing Treatment process,the water quality indicators in the standards and operating cost control has a greater advantage;the preferred pilot process effluent indicators: turbidity is 0.2NTU,color is 3 degrees,permanganate index is 1.90mg/L,ammonia nitrogen is 0.05mg/L,iron content is 0.01mg/L,manganese content is 0.03mg/L,are better than the water of the plant in quality.