Bioevaporation Treatment Of Concentrated Landfill Leachate From Two-Stage DTRO

With the development of social modernization process,the amount of municipal waste generated in China each year at a rate of about 10%of rapid growth,followed generated a lot of landfill leachate.At present,the Two-Stage DTRO(Disc-Tube Reverse Osmosis)process is a more mature and mature leachate treatment process in recent years,but it will produce higher organic matter concentration,more complex pollutants,higher processing costs,more difficult large concentrated liquid.Bioevaporation is a new technology to deal with high-concentration organic wastewater in recent years,the technology utilizes the metabolic heat released by the aerobic degradation of organic matter in high concentration organic wastewater itself to evaporate the waste water to achieve the simultaneous removal of organic matter and moisture in the wastewater.In this study,bioevaporation treatment of concentrated landfill leachate which is from Two-Stage DTRO has been conducted,in which sponge-biofilm was used as the microbial carrier and bulking agent,and food waste(FW)was used as the supplementary carbon source.Meanwhile,COD,airflow rate and addition of the mixture in each cycle were also optimized.With the sponge-biofilm as the microbial carrier and bulking agent,and the food waste as the supplementary carbon source,the concentrated landfill leachate could be effectively treated by the bioevaporation process.The higher the COD(0,18,40,80,120,160,200 g·L-1),the higher the temperature of the reactor,the better the bioevaporation performance.When the COD concentration of the mixture was 160 g·L-1,the temperature of the eight-batch bioevaporation reactor was up to 42.9-70.4?,the maximum duration of high temperature(45 ?)was 1.3 days,the total water removal rate was 86.2%.The bulk density increased from 133.7 g·L-1 to 179.2 g·L-1.When the COD concentration of the mixture was 160 g·L-1 and the addition was 100%,the influence of the four groups of different airflow rates(0.1,0.3,0.5,0.7 L·min-1)on the bioevaporation was obtained.Though higher temperature was observed,less water was removed while the pile was under lower airflow rate.Considering the pile temperature and water removal,0.5 L·min-1 was chosen as the optimal airflow rate in the bioevaporation process.The maximum temperature of the eight-wheel batch bioevaporating reactor was 43.3-69.6 ?,and the total water removal rate was 98.9%.The bulk density increased from 131.9 g L-1 to 140.5 g·L-1.When the concentration of COD was 160 g·L-1 and the airflow rate was 0.3 L·min-1,the effect of different addition(95%,90%,85%)on the bioevaporation was obtain in the trial with addition of 85%,the highest water and VS removal was achieved and bioevaporation sustainable and effective conduct,thus addition of 85%was thought to be the optimal addition,and five rounds of biological evaporation of water and VS total removal rate of 58.1%and 59.5%.When the concentration of COD was 200 g·L-1 and the aeration rate was 0.3 L·min-1,the effect of different addition(95%,90%,85%)on the bioevaporation was obtain in the trial with addition of 95%,the highest water and VS removal was achieved and bioevaporation sustainable and effective conduct,thus addition of 95%was thought to be the optimal addition,and five rounds of biological evaporation of water and VS total removal rate of 74.9%and 58.9%.The results showed that the COD concentration of the mixture was 160 g·L-1,the addition was 85%and the COD concentration of the mixture was 200 g·L-1,the addition was 95%.For the further comparison,the VS removal rate equivalent,but the mixed solution COD concentration of 200 g·L-1,addition of 95%moisture removal rate is higher,more removal.The purpose of this study is to remove the concentrate,so in practical applications,the mixed solution COD concentration of 200 g·L-1,addition of 95%more advantages.