Waste leachate treatment project in Laixi
Waste leachate project
Landfill leachate treatment has been a very difficult problem in landfill design, operation and management process. Leachate is the product of gravity flow of liquid in landfills, mainly from precipitation and internal water content of the waste itself. The nature of the leachate varies a lat due to many factors in the flow that may affect the its properties, including physical, chemical, and biological factors. Generally, the pH value is between 4 and 9, the COD is in the range of 2000 to 62000 mg/L, and the BOD5 is from 60 to 45,000 mg/L. The concentration of heavy metals is substantially the same as the concentration of heavy metals in municipal sewage. Landfill leachate is a high-concentration organic wastewater with complex composition. If it is discharged into the environment without treatment, it will cause serious environmental pollution. It is essential to treat leachate for the purpose of protecting the environment.
The landfill leachate generally has the following characteristics:
1) Complex composition, containing a variety of organic pollutants, metals, phytonutrients;
2) Organic matter concentration;
3) The high metal type is complex and contains more than 10 kinds of metal ions;
4) The ammonia nitrogen is high and the range of variation is large;
5) Composition and concentration vary with the seasons.
At present, China's treatment of leachate mainly includes biochemical treatment, incineration treatment and concentrated evaporation crystallization. Now, the concentrated evaporation and crystallization part is discussed:
MVR evaporation has good effect on the treatment of landfill leachate. It is not affected by temperature, PH, influent concentration and influent composition. It has less land occupation, high water production rate, convenient management, simple debugging, and can be opened and stopped at any time. It can be used for terminal treatment of waste leachate.
Project
|
No |
Item |
Introduction |
||
|
1 |
Name |
Waste leachate treatment project in Laixi |
||
|
2 |
Address |
Shandong Qingdao |
||
|
3 |
Treatment of wastewater industry |
Dangerous waste leachate wastewater |
||
|
4 |
Capacity |
1t/hMVR evaporator, 3t/hMVR evaporator, 4t/hMVR evaporator |
||
|
5 |
Process Technology |
Landfill Leachate - Biochemical Treatment - Reverse Osmosis - High Pressure Reverse Osmosis Treatment - Preheating System - MVR Evaporation Concentration - Mother Liquid Drying Treatment |
||
|
|
Raw Water |
Raw water index: raw water PH: 8.82; density 1.002g/ml; COD: 1520mg/L; salinity: 10.6%; conductivity: 9.88ms/cm; TDS: 4.93g / L; chloride ion: 2.1g / L; hardness : 360mg / L (calculated as calcium ion); The raw water has high hardness, and the raw water is softened and then evaporated. The evaporation temperature is about 92-95 °C. During the evaporation process,a lot of foam occur and the defoaming treatment is needed which will make sure good evaporation effect.The organic matter in the mother liquor is enriched in the later stage, resulting in higher evaporation boiling point. The mother liquor will be dryed after discharged from the evaporator. |
||
|
6 |
Process introduction |
First to reduce the COD of the waste leachate by biochemically treatment.After the RO reverse osmosis and the DTRO membrane concentration,the outlet water will meet discharge standard.The reverse osmosis concentrated water is finally treated by evaporation. The evaporating condensate water is dischaeged after it is cooled and treated by RO filter. |
||
|
7 |
Project Photo |
Inlet water |
Evaporation water |
Mother liquor after evaporation |
|
|
||||
