Studies On Semi Aerobic Landfill Leachate Denitrification Process Water Content At Two Different Temperatures

Facing with increasing penurious resource and deteriorating ecological environment, Municipal solid waste gradually become a prominent problem, It constraint urban development, waste resources, and destroy ecological environment. The treatment of municipal solid waste with semi aerobic landfill technology in our country is not so much. most of our city still use the traditional landfill technology to dispose large urban garbage, Due to land resources are limited, leachate of landfill are large and landfill gas escape in air bring about secondary pollution, All these are direct threat our soil and the atmosphere. It becomes an extremely urgent task to achieve sustainable development of human society and alleviate greenhouse effect.This experiment based on many semi-aerobic research and it can be carried out in laboratory simulation study, Four group test device are arranged.Each simulation experiment observed in different temperature, different moisture content of landfill in the law of organic matter degradation and waste nitrogen conversion relationship, the research can reduce landfill leachate volume and pollution load, shorten the cycle of waste degradation and optimize the engineering design provides reference dataTest carried out in 20 degrees and 35 degrees, The heat insulating device, air import and export temperature compensation, rain regular pouring, geotextile filter layer water distribution uniformity, cushion adopts quartz sand distribution, rainwater to irrigate constant temperature are taken to make sure the simulation of biological degradation state close to the actual landfill operation and avoid the larger negative impact such as the room temperature on the test and ensure stability of the test. The main conclusions are as follows:(1) Moisture content experiments:this experiment made some basic assumptions, simulate rainfall irrigation amount and fixed frequency; landfill in each layer permeability characteristic is consistent, that means the permeability coefficient is fixed; the initial moisture content of waste is uniformly fixed and each layer of garbage water character is the same. The calculated garbage permeability coefficient is 3.68 ×10-3 by the simulation(2) Simulation experiment column temperature change:this experiment uses two kinds of temperature to simulate experiment. In one condition, the packing column is placed in room and the temperature is fixed at 20 ℃, another condition the temperature is35℃. Experiment result show that under the constant temperature environment garbage in the reaction temperature is higher than that in the normal heap in reaction temperature (42-34 ℃). In general, temperature curve showed that the value increases first and then decreases gradually, this phenomenon coincidence with garbage quasi aerobic landfill degradation process.(3) A conclusion is obtained in the process of simulated rainfall.Although the litter moisture present periodic change, but the overall change tendency of total nitrogen and ammonia nitrogen have no significant effect. The main influence reflected in maintaining and changing waste water rate.On the degradation effect mainly manifests in the form of nitrogen with the movement of the water and quickly transfer from the upper to the lower layer, produce nitrite nitrogen accumulation or change the local reaction conditions.(4) In the simulation experiment process,waste water rate has remained at 60%, and increase and ensure its stable water content by the way of pouring rain periodically. Through degradation of organic matter and nitrogen to convert the test results can be tell that fixed state moisture content in favor of biodegradable garbage.(5) In this experiment, the success of the present experiment simulation is that it achieves a relative moisture content stable of garbage and rubbish in vivo reaction temperature, thus the test results are also relatively stable. During the test, it has been found that the landfill moisture content and ambient temperature is semi-aerobic landfill influence factor. Therefore, the degradation rate of garbage can be effectively increased by reasonable controlling moisture content and temperature.(6)By degradation of organic matter model under the test in landfill leachate COD average of three measured at 20 days to analysis, an analytical curve has a higher correlation can be inferred by the model at different temperatures in the leachate COD variation.