陕西省渭河扩建电厂粉煤灰处理场土壤对Cr(Ⅵ)的吸附作用

ADSORPTION OF SOIL TO HEXAVALENT CHROMIUM IN THE COAL ASH DISPOSAL SITE WITHIN THE EXTENDED WEIHE POWER PLANT IN SHAANXI

粉煤灰处理区的环境地质调查表明:由于受地面排放的粉煤灰的影响,地下水中Cr(Ⅵ)浓度高出背景值4~5倍.野外现场试验对Cr(Ⅵ)监测结果显示:在2m厚的灰体底部,下渗水中的Cr(Ⅵ)浓度已高达0.701ppm,超标14倍.很明显,Cr(Ⅵ)是粉煤灰中的主要污染质之一.老灰场的环境地质调查还发现:土壤对Cr(Ⅵ)的迁移有很大的阻滞作用.作者对此进行一系列野外及室内试验来研究粉煤灰中Cr(Ⅵ)的解吸,迁移及其与土壤之间的相互作用和有关的化学机理,并且评价了渭河扩建电厂新灰场区土壤包气带对粉煤灰中Cr(Ⅵ)的净化能力.

:The field investigation of coal ash disposal site shows that the concentration of hexavalent chromium in ground water had become four to five times higher than that of the background level under the influence of the land-disposed coal ash. The result of water quality monitored in the field test indicates that, at the bottom of two-meter thick coal ash, the concentration of hexavalent chromium in the lecheate has reached 0.701mg/1, four-teen times greater than the drinking standard. The field investigation also shows that the soils play an important part in preventing the migration of the pollutants. A series of field and lab. tests have been carried out to study the desorption, migration of the element and the intereaction between hexavalent chromium and the soils. Based on these results, some measures are proposed to protect the ground water in the coal ash disposal site to avoid from pollution.