Study On The Pollution Characteristics And Recycling Of Waste Bag Duster From The Pb&Zn Smeltery

Bag filter is applied widely in various dust collector, in terms of number, bag filter accounts for over60% of dust remover, and over70% fiue-gas treatment capability. In recent years, with the rapid development of electromagnetic pulse valve and filter, filter processing technology have be matured gradually. The problem of application of bag filters in coal-burning boiler have been solved, the application of bag filters have become more and more wider, and much waste bag duster be produced. The key to slove the problem of waste bag duster environmental pollution in our country is to find the method for controlling the pollution of waste bag duster and seeking the methods reclaiming into local conditions.This study is based on the above objective. Waste bag duster and fly ash were taken from a lead-zinc smeltery in Guangdong, the samples were dissolved in different proportioning of HNO3-H2O2-HF system and digested used microwave, extracted with Community Bureau of Reference (BCR) three-step method to determine the total content and different form content by FASS for the Cu、Zn、Pb、Cr、Ni、Cd sequentially; After obtained the best digestion microwave condition, using ashing dry and digestion microwave to deal with the samples respectively, determing heavy mentals content in samples by using FASS, in the same time, determined the standard sample using the same method, and in contrast with standard value to test the method degree of accurancy and precision; At last, cut the waste bag duster into pieces, mixed with tannery sludge and carried out the solidified experiment, looking for the ways for the waste bag duster pollution controlling.The results of the pollution characteristics of waste bag duster showed that the best acid system (HNO3:H2O2:HF) proportioning of waste bag duster decomposed by microwave digestion was10:2:2. Under the best conditions of microwave digestion, the content of heavy metals in the waste bag duster and fly ash exceeded the third class standard of the soil environmental quality standard(GB15168-1995). Heavy metals had kinds of forms in the fly ash. Ni mainly existed in residual and exchangeable fractions form. Cu and Pb were mainly in the state of residual species. The four species of Zn were distributed even, Cd and Zn had higher potential transformation. The different decomposition methods influenced measurement results of elements in various degrees. Microwave digestion is of higher accuracy and reagent utilization than dry ashing, which is more benefit to the element analysis. The precision of two methods were less than5%RSD(n=11).The results of solidification of waste bag duster and tannery sludge showed that addition of waste bag duster promoted the compressed strength and mechanical properties of sludge block, during the solidification experiment, it was mixed with cement、PFA and cinder, enhanced the solidification of heavy metal in the waste bag duster,heavy metal concentrations satisfied with the related standards. After curing, water ratio of the solidification block kept about35%, satisfied with the standards on landfill.