| Landfill leachate, which yield from the processes of MSW(municipal solid waste), is a kind of highly concentrated wastewater. Since the fluctuation of quality and quantity, full of harmful pollutants, and great difficulty of treatment, there is still not a efficient method for the processing of it. In this dissertation, experiment and mechanism of essential diatomite as adsorbent for the treatment of landfill leachate was studied. The main parameters, which affect the absorbing process, including diatomite dosage, solution pH, adsorption time and initial concentration of leachate, etc.. Experimental results showed the following regular patterns: under the hydrodynamics condition of 250r/min(2min)+50r/min(1min), the best static adsorption parameters are as following: diatomite dosage was 5g/L, the benefiting pH value was 6~8 and retention period was 20min. By relying on the standard test methods, under the optimum technical parameters, the absorbing type, mechanism and factors which affect the process of adsorption were studied. The adsorb mechanism include physical and chemical adsorption, the former is the main adsorption, and include depth filtration and molecular sieving properties as well. Experimental results showed that, under the best parameters, the adsorb ratios of turbidity, COD, ammonia-nitrogen are 98%, 49.22% and 26.15%. From the characteristic of diatomite adsorbing leachate, we can conclude that when it used in pretreatment process it can remove SS efficiently which will create a better condition for later treatment, and improved the biodegradability of leachate by remove COD. when used in deep treatment process it can make leachate meet the discharge standard.
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