Biological Purification Of A Typical Groundwater With High Concentration Of Iron And Manganese In Jiamusi And Engineering Application

Jangbei Water Plant supplies groundwater with high concentration of iron andmanganese in Jiamusi. The treatment of the groundwater with high concentration of Feand Mn using a well-established biofilter was studied in this paper. The first, Seed sludgewas inoculated and cultivated in biofilter. The second, the test treats the groundwaterwith high concentration of Fe and Mn using anthracite sand fiter, and the removal rules,influencing factors, the best operation parameters and management of the plant wereinvestigated.Seed sludge was inoculated and cultivated in biofilter. Domestication conditionswere2m/h of filtration velocity,2min of backwash time,72hours of backwash cycle and11L/(s·m2) of backwash intensity after continuous aerated to enhance cultivation. Thecultivation continued for3~5months under weak backwash intensity and low filtrationvelocity before effluent water quality mets the national standard of drinking water. Then，the filtration velocity of biofilter was gradually increased to6m/h in1m/h stepwise.The concentration of iron and manganese in influent was12~18mg/L and0.5~1.2mg/L, and the effluent is lower than the National Drinking Water Standard(Fe＜0.3mg/L,Mn＜0.1mg/L). The best operation parameter of the groundwater with highconcentration of Fe and Mn using a well-established biofilter was6m/h of filtrationvelocity,5min of backwash time,72hours of backwash cycle and12L/(s·m2) ofbackwash intensity.The test analyses influence conditions of purification process, such as filtration rate,backwash, temperature, pH, and nutrient. The filtration velocity of biofilter was graduallyincreased from6m/h to9m/h, which has any effect for the water quality of the effluent. Itshows mature anthracite after cultivation is a high-quality filter material. Temperatureand pH of raw water is6.5℃and6.67～7.20respectively. It is very suitable for iron,manganese oxide bacteria to grow in biofilter.Iron, manganese oxide bacteria isoligotrophic microbes, permanganate of raw water is only1.2mg/L, show that nutrient isthe limiting factors for iron, manganese oxide bacteria to grow.The filtration velocity of biological iron and manganese removal technology mustbe gradually increased to design velocity in1m/h stepwise and prohibits to suddenlyincrease. On-site experiments were performed to determine the reasonable backwashcycle and intensity.