Abstract: Evaporation is much higher than rainfall in arid loess area， evaporation reduction by irrigating soil cover was a feasible way to treat landfill leachate in situ in this area. In order to find out the influencing factors of evaporation reduction， the correlation between evaporation of loess irrigated by leachate and meteorological conditions， irrigation intensity （soil moisture content after irrigation） and leachate water quality were studied by simulating the cover layer in a landfill in Lanzhou. The results showed that the local water surface evaporation（E1） was mainly related to temperature（T）， pressure（P）， air humidity（HUM）， wind speed（W）， precipitation（R） and sunshine duration（S）. The fitting equation was E1=12.529+0.256T-0.010P-0.062HUM+0.351W-0.007R+0.022S. There was a linear relationship between the water surface evaporation of pure water and leachate. Under different soil water content of 25%， 20% and 15%， the evaporation of leachate irrigation decreased with the decrease of water content， and the evaporation at 25% water content was the maximum under non-liquefaction conditions. According to the meteorological data of the test site， the annual water surface evaporation was 1 405.82 mm， and the leachate irrigation evaporation was 806.09 mm. The annual evaporation loss of leachate per unit area of loess overburden was about 0.8 m3m2.The efficient treatment of toilet black water and yellow water was an essential component of current wastewater treatment. According to the research process and treatment mode， the black water treatment technology could be divided into centralized black water treatment technology， dispersed black water treatment technology， emerging black water treatment technology and black water resource technologies. Most technologies， including biological， physicochemical， and other treatment methods， were focused on the treatment and recovery of nutrients due to the high concentration of nitrogen and phosphorus resources in source-separated yellow water. The different technical characteristics， principles， research status and application cases of black water and yellow water were summarized. And the corresponding development directions， such as source separation technology development， micro-pollutants advanced treatment and high-quality resource recovery were proposed.

Key words: soil evaporation, water surface evaporation, leachate recharge, multiple linear regression