Garbage infiltration device

1、 Introduction to garbage infiltration device:
Garbage leachate refers to a high concentration wastewater formed by the moisture contained in the garbage itself in the landfill, the rain and snow water entering the landfill, and other moisture, after deducting the saturated water holding capacity of the garbage and soil layers, and passing through the garbage and soil layers.
The water quality of garbage leachate is quite complex, generally containing high concentrations of organic matter, heavy metal salts, SS, and ammonia nitrogen. Garbage leachate not only pollutes soil and surface water sources, but also pollutes groundwater. There have been many studies on the removal of CODCr in garbage leachate, and biological methods are generally used for treatment, but the treatment effect is not very ideal and the operating cost is relatively high.
2、 Process characteristics of garbage infiltration device:
1. Adopting mature technology to meet the requirements of new standards
2. Efficient removal of nitrogen (ammonia nitrogen and total nitrogen) is one of its major features
3. Small footprint, low investment, and low operating costs
4. Short construction period
5. Easy maintenance and management
6. Save tedious construction drawing design tasks
7. Detachable and transportable
2、 The garbage infiltration device is divided into five stages:
1. Initial adjustment stage: Garbage is filled into the landfill, and the stabilization stage of the landfill enters the initial adjustment stage. During this stage, the easily degradable components in the garbage rapidly undergo aerobic biodegradation reactions with the oxygen carried in the garbage, generating carbon dioxide (CO2) and water, while releasing a certain amount of heat.
2. Transition stage: During this stage, the oxygen in the landfill is consumed, and anaerobic conditions begin to form in the landfill. The degradation of garbage transitions from aerobic degradation to facultative anaerobic degradation. At this stage, nitrate and sulfate in the garbage are reduced to nitrogen (N2) and hydrogen sulfide (H2S), respectively, and the pH of the leachate begins to decrease.
3. Acidification stage: When hydrogen gas (H2) is continuously produced in the landfill, it means that the stabilization of the landfill has entered the acidification stage. The microorganisms that play a major role in garbage degradation at this stage are facultative and transitional anaerobic bacteria, and the main component of landfill gas is carbon dioxide (CO2). The COD, VFA, and metal ion concentrations of leachate continue to rise to their maximum values in the middle stage, and then gradually decrease thereafter; The pH continues to decrease to its lowest value and gradually increases thereafter.
4. Methane fermentation stage: When the H2 content in the landfill reaches its lowest point, the landfill enters the methane fermentation stage, during which methane producing bacteria convert organic acids and H2 into methane. The concentration of organic matter, metal ions, and conductivity all rapidly decrease, BOD/COD decreases, biodegradability decreases, and pH begins to rise.
5. Mature stage: When the easily biodegradable components in the landfill waste are basically degraded, the landfill enters the mature stage. At this stage, as the vast majority of nutrients in the garbage have been removed with the leachate, only a small amount of microorganisms degrade some difficult to degrade substances in the garbage. At this time, the pH is maintained in a slightly alkaline state, and the biodegradability of the leachate further decreases, with BOD/COD less than 0.1. But the concentration of the filtrate is already very low.