Experimental Study On The Selection Of Solid Organic Carbon Source For Denitrification Of Groundwater

Emissions of nitrogen compounds have increased dramatically in recent years,with the development of industry and agriculture as well as the population growth.This fact leads to the increasing concentration of nitrate in the groundwater,which has caused continuous deterioration of the water quality.The contamination of nitrate in groundwater has become an ever-increasing and worldwide environmental problem.In this paper the corncob,kitchen waste and leaves were used as the solid organic carbon source and biological carrier;secondly,we have making a unified standard of nitrate pollution bioremediation reactor,and have making a comparison under various conditions in the denitrification of nitrate removal efficiency.The removal rates of nitrate nitrogen in different solid organic carbon sources,hydraulic retention time and different biological carriers were compared.The following conclusions can be drawn:1)Peristaltic pump flow rate is 8 rad/min,influent nitrogen content is 100 mg/L,the reaction temperature is 28 degrees Celsius conditions,corncob,bones,leaves such as carbon source,hydraulic retention time(HRT)set the gradient were 4h,4.5H,5h,5.5h,6h,6.5h,7h,7.5h,8h 12 h,14h,10 h,and 16 h.With the increase of hydraulic retention time,corncob,bones and leaves as carbon source was proportional to the rate increase,the nitrate nitrogen and total nitrogen removal,the bones as carbon source the highest rate of nitrate nitrogen and total nitrogen removal,but when the hydraulic retention time of 10 hours or more,three kinds of carbon sources the nitrate nitrogen and total nitrogen removal rate of growth slowed.2)With the increase of nitrogen content,the removal efficiency of nitrate nitrogen was decreased,but the content of ammonia nitrogen and nitrite nitrogen increased significantly.3)The natural solid organic carbon source provides carbon source and electron donor,and as the carrier of microbial growth,it can solve the problem of low autotrophic denitrification capacity and difficult to control the dosage of heterotrophic denitrification carbon source.