Recovery process and equipment for ammonia leachate in sanitary landfill of domestic waste

Abstract

The invention provides a process and equipment for recovering ammonia from landfill leachate of domestic waste sanitary landfill. The first step is to remove ammonia from the landfill leachate: adding alkaline chemicals to the leachate to adjust the pH of the leachate The value is 9-11; the ammonia in the landfill leachate is removed in the deammonization tower by air stripping; the second step is the recovery of ammonia: the ammonium sulfate is recovered by the sulfuric acid solution absorption method for the ammonia-containing gas. Two absorption reactors are used for absorption. In the first absorption reactor, 85% to 95% of the ammonia-containing gas is treated. The concentration of ammonium sulfate in the circulating mother liquor of the first absorption reactor is lower than the saturation concentration of ammonium sulfate. Avoid the generation of ammonium sulfate crystallization; the unsaturated circulating mother liquor in the first absorption reactor is sent to the second absorption reactor to continue to react with 5% to 15% ammonia-containing gas, so that the second absorption reaction circulates in the mother liquor The concentration of ammonium sulfate is higher than the saturation concentration of ammonium sulfate, which promotes the generation of ammonium sulfate crystals; the third step is the separation of ammonium sulfate crystals.

Description

technical field [0001] The invention relates to a recovery process and equipment for ammonia leachate in domestic garbage sanitary landfills, and in particular to the technical field of domestic garbage treatment and utilization. Background technique [0002] Sanitary landfill is a method of disposing solid waste widely used in my country in recent years. For an anaerobic landfill, its mechanism is to use anaerobic fermentation method to convert organic matter in garbage into gaseous products such as carbon dioxide and methane through the degradation of anaerobic and facultative microorganisms. Since municipal solid waste itself contains a lot of water, it will leach out in the form of leachate during the bioconversion process. At the same time, affected by factors such as rainfall and runoff, landfills will also pass through percolation to form landfill leachate. [0003] The composition of landfill leachate is complex, and its composition depends not only on the landfill...

AI Technical Summary

Problems solved by technology

In particular, it solves the equipment problem of reaction between ammonia-containing gas and sulfuric acid after deamination, overcomes the problems of high cost of ammonium sulfate saturator process equipment, easy blockage of pipelines by ammonium sulfate crystals, frequent equipment maintenance and other problems, high absorption efficiency, and simple operation and management.

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