(a) back spray method
In view of the leachate some more dry matter, can take back to spray method to increase the rate of combustion, lower the content of harmful substances in the leachate, burning again need to judge according to the calorific value of leachate, using high-pressure device for injection, when heat is lower than the standard, burning from the leachate will stop back to spray, continue to accumulate in the centralized pool, stay concentration heat amount to mark again, can undertake injection, guarantee the processing efficiency.
Before choosing this treatment method, it is necessary to measure the production amount and heat of the leachate. This technology is not suitable for use in the case of high production and low heat, and flameout may occur, and the treatment effect is not ideal. In some kitchen waste treatment, the backspray method is commonly used and has achieved good results.
(2) reverse osmosis method
In the treatment of landfill leachate with high salt concentration, the reverse osmosis method is often used. The leachate in the future and after incineration is controlled within the designated area, so as not to cause a wider range of pollution effects due to infiltration in the soil.
After burning garbage, leachate concentration is far greater than accumulation amount, content of suspended matter more, also USES the isolation of reverse osmosis membrane, after this processing method can help solve the problem of the current common garbage pollution, reverse osmosis membrane surface accumulation of a large number of floating garbage, should timely replacement, otherwise the isolation effects of leachate can't display.
Reverse osmosis method is mainly to increase the concentration of leachate and isolate suspended pollutants, so that the final leachate is naturally ultra-high concentration, and it is also very difficult to deal with it. Reverse osmosis is usually used in combination with other methods to re-burn the resulting high concentration of liquid, greatly reducing the amount of harmful substances in it.
Reverse osmosis concentrate processing is a difficulty, the concentrate of landfill leachate can use recharge landfill area, landfilling adsorption on degradation of concentrate, heavy metals and organic matter in the incinerator leachate treated with reverse osmosis concentrate and produced more than 50%, because there is no convenient conditions of landfill site injection, back to the water injection incinerator is too big, therefore with membrane treatment method and treatment of leachate is the premise of concentrate processing solution.
(3) biochemical treatment
Some chemical reagents are added to the osmotic solution, so that part of the contaminant can continue to be reacted, and the final substance generated can be controlled within the specified standard in terms of the content of contaminant. The main principle of chemical reaction is oxidation reaction, which decomposes and treats polluting substances. This method can completely solve polluting substances, but it also has disadvantages. After reacting one kind of substance, another kind of substance will be generated, and improper control will still cause secondary pollution.
Incinerators leachate treatment is mainly to reduce pollution, although biochemical treatment method can solve part of the problem of pollution, but it is easy to cause the pollution of other aspects, the application before we will strictly control the quality on the chemical, reaction control at reasonable level, oxidation reaction after thoroughly pollutants content will decrease.
An incinerator used Feton reagent oxidation + to remove + coagulation sedimentation + anaerobic ammonia oxidation + SBR + ClO2 + activated carbon adsorption process leachate, the actual process mostly depend on chemical oxidant and activated carbon adsorption removal of pollutants, from the point of operation result, dosing normal water can meet the national level 3 emission standards, but the operating cost is as high as more than 120 yuan/t.
