Calcium Peroxide Complex Agent In-situ Remediation For River Sediment Pollution

Remediation of black and stinky water bodies is the hottest issue in current water environment governance and the most difficult environmental problem.Contaminated river sediments are the main source of endogenous pollution that leads to black body odor.The bottom mud is rich in nutrients,Released again into the overlying body of water within a period of time,easily cause secondary pollution,Therefore,it is particularly important for the repair of contaminated sediments.In-situ chemical remediation technology can effectively curb the black odor problem of contaminated sediment.Its treatment effect is fast,the effect is obvious,the secondary pollution is small and other characteristics become the ideal treatment method.Single-dosing chemical remediation has some limitations in the repair process.This topic explores the effect of a single agent on the overlying water in sediment remediation.At the same time,through different combinations of pharmaceutical agents,Exploring compound pharmaceuticals,and analyzing the purification effects and optimal conditions of use the composite agents on black and odorous bodies of water.The subject is to study the sediment of contaminated water,focusing on the Chemical remedies(Ca O2,PAC,Ca(NO3)2)effects overlying water body COD,bottom black mud and odor(acid volatile sulfur AVS index),NH4+-N and TP.At the same time the subject to explore the use of compound agents,designing orthogonal experiments to optimize the conditions of use of the agents.The following conclusions can be drawn: Removal of AVS is Ca O2> Ca(NO3)2>PAC,Ca O2 processing efficiency reaches 70%.NH4+-N increased after pharmaceutical dosage,Increase rate is Ca(NO3)2> Ca O2> PAC.For total phosphorus removal is composite passivator > Ca O2> Ca(NO3)2> PAC;Removal efficiency of COD is composite passivator> PAC >Ca O2> Ca(NO3)2.After an experimental investigation,the optimized conditions for the effect of the composite agent on the ammonia nitrogen in the overlying water are: The p H is alkaline and the reaction time is 30 days.In the order of addition,polyaluminum chloride is added first and calcium peroxide is added again.The greatest impact on the removal rate of total phosphorus in overlying water bodies is: Neutral control of p H,reaction time of 20 days and dosing schedule.The optimized conditions for the restoration of overlying wat er body COD : The p H value is acidic,the reaction time is 20 days,and the order of administration is the addition of polyaluminum chloride followed by calcium peroxide...