Study On The Effects Of Water Purification Processes On The Removal Of Antimony

Quantities researches not only from China,but also from abroad have shown that antimony has cumulative toxicity and carcinogenicity to human.Presently,the deeper removal of antimony in city water is still very rare.Besides,once the water source occurs sudden water pollution,and the pollution load is beyond the processing capacity of prefilter facilities,the water purification technology,as a temporary emergency countermeasures and "the second line of defense",whether can effectively remove the antimony and other contaminants in the water to ensure the safety of drinking water,needed to be further studied.Aiming at the above problems,this study studied:(1)the effect of different water purification technologies on antimony removal in city water,(2)the effect of different water purification technologies on antimony and other pollutants removal in water from water source.The conclusions are as follows:(1)Different water purification technologies have obvious different effects on the antimony removal rate.For trivalent antimony removal efficiency,the optimal technology was reverse osmosis filter,followed by nanofiltration,then by ultrafiltration,finally by the carbon block filter;While for pentavalent antimony removal efficiency,reverse osmosis and nanofiltration filter had the optimal effects,followed by carbon block,finally by the ultrafiltration.According to the characteristics of membrane and parameters,reverse osmosis membrane obtained the optimal ratio of antimony removing in the clean water,under the condition of the running water of 1000 L,trivalent antimony and pentavalent antimony removal efficiencies were as high as 94% and 94% respectively.(2)Different water purification technologies have obvious different effects on the removal rate of antimony,as well as other pollutants.The antimony removal rate for carbon block,fiberdyne,ultrafiltration membrane,nanofiltration membrane and reverse osmosis membrane,nanofiltration membrane+fiberdyne and reverse osmosis membrane+carbon block were 28.7%,13.5%,7.3%,98.5%,99.0%,99.2% and 99.2%.From the viewpoint of oxygen consumption removal efficiency,nanofiltration membrane and reverse osmosis membrane,nanofiltration membrane+fiberdyne and reverse osmosis membrane+carbon block had the obvious removing effects,however,ultrafiltration membrane had a poorer purification effect on oxygen consumption,the removal rate is only 2.9%.Carbon block,fiberdyne,reverse osmosis membrane,nanofiltration membrane+fiberdyne and reverse osmosis membrane+carbon block had satisfactory effects on ammonia nitrogen removal,followed by nanofiltration membrane,the ultrafiltration membrane has little effect on ammonia nitrogen removal,the removal rate is only 1.3%.From hexavalent chromium removal,reverse osmosis membrane and reverse osmosis membrane+carbon block performed best,the hexavalent chromium removal ability decreased with the increasing running water for carbon block,and the final removal rate was 75.9%.fiberdyne,ultrafiltration membrane,nanofiltration membranes and nanofiltration membrane + fiberdyne had relatively poor effect on hexavalent chromium removal.(3)The antimony,oxygen consumption,ammonia nitrogen and hexavalent chromium were served as evaluation indexes,entropy weight coefficient evaluation model was introduced,and the different purification technologies were evaluated and selected.Taking antimony removal rate as the main index while considering other indicators,thus the most optimal technical solution was reverse osmosis membrane + carbon block,suboptimal solution was reverse osmosis membrane,however,ultrafiltration membrane purification was relatively poorer.