Study Of Wastewater Treatment Method Of Dental Amalgam

With the social and economical development,dental health is getting more and more important. Obviously,the dental clinic is booming rapidly. The widely used amalgam to stuff in dental caries will produce lot of sewage disposal. It is proved the amalgam will transform to virulent methyl mercury which will definitely jeopardize humans'health.Therefore,this article will raise and research two effective methods to handle amalgam disposal.This research stimulated the amalgam disposal in daily clinical operation,based on treatment of landfill leachate and Membrane technology,according to Orthogonal design,respectively to discuss the related factors under the two different methods,and using analysis of variance to identify the better parameters in the application of two methods.The coagulation and deposition method indicated: influencing factors included coagulant,dosage,PH value,coagulant aid dosage,temperate. The analysis of variance showed , coagulant , dosage and coagulant aid dosage did have dramatically statistical significance (p<0.05).The major and minor relationship was: coagulant>dosage>coagulant dosage. PH value and temperate influenced little(p>0.05). Based on the single factor analysis and total mercury factor,the optimum program was: Polyaluminium chloride (PAC) 35mg/L,Polyacrylamide (PAM) 15 mg/L,PH and temperate in normal conditions. According to single factor statistical analysis,under the mixture of factors,the total mercury fell 95% of confidence interval in mean of population,which could not fully comply with national medical agency for discharge standard of water pollutants (GB 18466—2005,total mercury density less than 50μg/L).Membrane treatment of total mercury results indicated: the experiment took use of plate form Micro-filtration as end-filter,the influencing factors included membrane materials,PH value,temperate. The analysis of variance showed,membrane materials sig. is 0.013,had dramatically statistical significance (p<0.05),PH value and temperate influenced little (p>0.05). Based on the single factor analysis and total mercury factor,CN-CA membrane was proved to be the best material in this experiment. According to single factor statistical analysis,under the mixture of factors,the total mercury fell 95% of confidence interval in mean of population,which could wholly comply with the national medical agency for discharge standard of water pollutants (GB 18466—2005,total mercury density less than 50μg/L).Membrane treatment of leaching time results indicated: the effectiveness influencing factors included membrane materials,PH value,temperate. The Analysis of variance shows,membrane materials,PH value and temperate all had dramatically statistical significance (p<0.05),the major and minor factors on effect of membrane flux were: PH value> membrane materials> temperate. Based on the single factor analysis,according to less leaching time and higher efficiency,the result showed when PH=12,temperate=45℃,Poly Ether Sulfone(PES) membrane would reach the highest membrane flux .The studies showed that ,to some extent,the coagulation and deposition methods could deal with waste water of dental amalgam ,but which could not fully comply with national standard. Membrane treatment method could achieve national standards,but they were limited by terms of membrane treatment efficiencies. In order to get the requested effect and efficiency,we should improve operations and perfect technologies according to the existing practices.