Treatment method of landfill leachate

Abstract

The invention discloses a treatment method of landfill leachate. The method comprises the following steps: removing suspended matters and floating matters in the landfill leachate by a mechanical grille, and adding PAC (polyaluminium chloride) and PAM (polyacrylamide) into the leachate to perform coagulation sedimentation and ultrafiltration treatment to remove metals, SS (sulindac sulfides) and partial organic matters in the leachate and reduce the treatment load of a follow-up membrane biological fluidized bed unit; then enabling the leachate after treatment to enter the membrane biological fluidized bed, maintaining the relatively high sludge concentration in the membrane biological fluidized bed, and performing biological treatment to remove soluble COD (chemical oxygen demand), BOD (biochemical oxygen demand) and ammonia nitrogen in the leachate; and finally removing the organic matters and salts, which are difficult to degrade, by a reverse osmosis membrane so as to realize up-to-standard emission of outlet water. The treatment method disclosed by the invention has the advantages of strong ability of being suitable for changes in water quality, high impact-resistant load, short treatment period, high treatment efficiency, good effect on removing pollutants, high removal rate of the COD, BOD and ammonia nitrogen of above 97%, small occupied area, high degree of automation and low cost.

Description

Technical field [0001] The invention relates to a waste water treatment method, in particular to a waste leachate treatment method. Background technique [0002] Landfill leachate refers to the black-brown-red liquid that leaks from the landfill due to fermentation, rainwater washing, washing, and surface water soaking during garbage stacking and landfilling. It is a high-concentration organic wastewater with very complex components, large changes in water quality and quantity, and a long duration of damage. It is one of the main factors that cause secondary pollution in the landfill process. Generally speaking, the pH of the landfill leachate is between 4-9, and the COD Cr In the range of 10000~40,000mg / L, BOD 5 In the range of 5000-8000 mg / L, the ammonia nitrogen is in the range of 1000-2000 mg / L. [0003] Due to the high pollution load of landfill leachate, it is difficult to treat. Not only the effectiveness and stability of the treatment project, but also the economic rationa...

AI Technical Summary

Problems solved by technology

[0004] (1) Poor ability to adapt to water quality changes, especially poor ability to adapt to water quality changes throughout the landfill period

As the landfill leachate water quality prolongs with the landfill time, the BOD 5 / COD Cr It shows a downward trend, and the system will run well in the early stage of landfill, but the system will not adapt to it in the later stage

[0005] (2) Cannot meet the requirements of the secondary standard in my country (GB16889-1997)

[0006] High concentration of organic pollutants and refractory substances and high concentration of ammonia nitrogen lead to long process flow, many structures, complex management, large floor area, high operating costs, and effluent COD Cr and ammonia nitrogen are not easy to reach the standard