Garbage leachate is a highly concentrated organic wastewater with extremely complex composition, containing a large amount of organic pollutants. It not only has high ammonia nitrogen and salt content, but also contains more than ten metal ions, which are toxic, with imbalanced biological nutrition ratio, large changes in water quantity and quality, deep color and foul odor, making it difficult to treat.
Based on the existing problems in leachate treatment, the key to the current leachate treatment process in China mainly focuses on solving the difficulties in high concentration ammonia nitrogen treatment technology and leachate deep treatment technology.

The methods of re spraying (re injection) treatment, physical and chemical treatment, biochemical treatment, and membrane separation are the existing technologies for treating leachate from garbage. The following mainly introduces membrane separation technology to you:

Membrane separation technologies mainly include ultrafiltration membranes, reverse osmosis membranes, nanofiltration membranes, and membrane bioreactors. The technical characteristics of membrane separation: no phase change occurs during the membrane separation process, and the energy conversion rate is high; In general, there is no need to add other substances, which can save raw materials and chemicals; During the membrane separation process, simultaneous separation and concentration can greatly reduce the amount of concentrated solution that needs to be refilled; The membrane separation process is not affected by external temperature changes and can be suitable for various climatic conditions; Easy to automate control; The effluent quality is good and stable.

Membrane treatment technology is an emerging treatment process, but its concentrated solution can cause the accumulation of pollutants, which will increase the difficulty of treatment over time. Moreover, the problem of membrane fouling has not been well solved, resulting in frequent replacement of membrane components and high operating costs. Moreover, this process itself has the problem of high energy consumption. Disadvantages of membrane separation: large one-time investment, requiring high professional technical level of operation, maintenance, and management personnel; High operating costs; Strict pre-treatment facilities must be equipped to ensure the safe long-term operation of membrane filtration; Recharge of concentrated solution can lead to the accumulation of pollutants in leachate, especially difficult to treat ammonia nitrogen, which is higher.

Due to the high investment and operating costs of membrane separation, it is generally difficult to accept economically in China. In recent years, due to the fact that traditional biochemical treatment does not meet the standards and there is no other effective method with relatively low investment and operating costs, some leachate treatment projects in economically developed areas only use membrane separation as a deep treatment after biochemical treatment. The treated water is used for washing vehicles, reducing dust on roads, and greening in the area.


The above figure is a schematic diagram of the membrane separation technology for garbage permeate. Nanofiltration unit (reverse osmosis separation technology) can effectively filter out organic pollutants, inorganic components, heavy metals, and microorganisms in the leachate of garbage, enabling it to meet emission standards and return to landfills or pH adjustment tanks.