| Sanitary landfill is the main process of the municipal refuse treatment, and it will produce landfill leachate that is very harmful for the environment. The landfill leachate is a complex wastewater with considerable variations in composition, and high concentration of COD,heavy metal ion and ammonia-nitrogen. Pollutant concentration of the landfill leachate used to change largely. Currently, all of the processing craft in domestic and foreign are divided into three segments; the biological treatment is taken as the main body craft, the physical-chemical treatment and land method are taken as the pretreatment craft and the post-processing craft, respectively. The experimental use of mineral resource-rich, low prices of bentonite as absorbent pretreatment municipal leachate, it is an important supplement to the pretreatment leachate.Through the experimental study showed that the methodology which the pretreatment leachate using bentonite is feasible, and sodium bentonite is better as treatment Pharmacy.The main parameters,which affect the absorbing process,including bentonite dosage,solution pH,adsorption time and Static-time,etc.Sodium bentonite adsorption optimum conditions are as follows: pH value of 7.0, adding to 15 g / L, water conditions 250 r / min (3min), Static-time 1 hour. In the coagulation conditions, the leachate SS removal rate is 74.2 percent, CODcr the removal rate is 45.3 percent, ammonia nitrogen removal rate is 39.5 percent.Based on the test results of that analysis of the mechanism, the leachate bentonite in the absorption of pollutants The adsorb mechanism include physical and chemical adsorption,the former is the main adsorption,and include depth filtration and molecular sieving properties as well.
|
PDF Full Text Request