The Removal Of Chromium From The Soil Of The Chromium-slag Pile

Chromium is a kind of important environmental pollutants in the soil. If it getsinto the soil, it would contact with the natural environment though a series of naturalcolloidal physical or chemistry reaction such as: redox, coordination, adsorption,precipitation, etc. These properties would influence various pollutants in soilenvironmental behavior. Chromium can get into groundwater by rain leaching andthawing which make pollution to surrounding environment or through biologicalenrichment function, with the geometric growth of human health.For the special physical and chemical properties, the chromium removal hascertain difficulty. Innocuous removal of chromium in soil has become an internationalproblem. For chromium pollution in soil, there is no international standard, in theactual operation, should be based on the remediation of specific uses, repair and soilcover vegetation resistance ability to choose corresponding repairing chromium targetand means. Currently more popular repair methods mainly include microbiologicalmethod, electrochemical method and physical curing method. But a variety ofmethods have their own defects, not suitable for large-scale promotion.This paper proposes a chromium slag heap the contaminated soil by leachingmethod, the soil samples of chromium is transferred to the eluent, obtained betterleaching removal effect, and the use of sodium sulfide, ferrous sulfate system, will theeluent in chromium enrichment, on enrichment of sludge were roasting treatment. Thewhole process is basically no energy consumption and secondary pollution, is a clean,harmless soil removal methods for chromium. Experimental also study eachinfluencing factor’s effect in different steps, on the whole process control arediscussed.The results show that, the effect of soil chromium leaching removal efficiency factors are divided into two aspects, one is the leaching factors, namely the pH of theeluent, leaching time; the other one is the soil particle size and other factors.Experiments show that, the elution process should be mainly in the alkalineenvironment. The leaching time and leaching rate are in inverse ratio with theleaching pH. Soil particle size can also affect the leaching effect, in particular a soil,soil characteristics should be based on the selection of suitable experimentalexpectations and specific experimental conditions. Experimental study on sodiumsulfide and ferrous sulfate removal of chromium in water, stirring speed and time onthe removal efficiency of leaching, the proper removal conditions.