Biochemical landfill leachate treatment process

Abstract

The invention discloses a biochemical landfill leachate treatment process, which comprises: adjusting the pH value of landfill leachate with an ammonia nitrogen concentration of more than 2000 mg / L and B / C of less than 0.2 to 8-9, and filtering; precipitating the filtered landfill leachate in a coagulation pool; carrying out electrolysis treatment on the effluent of the coagulation pool for 20-30min in an electrolysis tank with a voltage of 3-5 V by using a titanium alloy electrode and a composite electrolyte, wherein the composite electrolyte comprises sodium hydroxide and hydrochloric acidfor adjusting the pH value of the effluent of the coagulation pool to 6-9, sodium chloride for adjusting the TDS value of the effluent of the coagulation pool to more than or equal to 6000 mg / L, and sodium hypochlorite for adjusting the redox potential of the effluent of the coagulation pool to more than -300 mV; and sequentially carrying out catalytic ozone oxidation treatment and biochemical treatment on the effluent of the electrolysis tank. According to the present invention, with the process, by adjusting the TDS value and the redox potential, the direct oxidation effect and the indirectoxidation effect in the electrolysis reaction are optimally balanced so as to obtain the optimal ammonia nitrogen and COD removal effect at low energy consumption.

Description

technical field [0001] The invention belongs to the technical field of wastewater treatment, and in particular relates to a biochemical landfill leachate treatment process. Background technique [0002] Landfill leachate refers to the moisture contained in the garbage itself in the landfill, the rain and snow water and other moisture entering the landfill, deducting the saturated water holding capacity of the garbage and the covering soil, and passing through the garbage layer and the covering soil. A high concentration of organic wastewater. Its characteristics are: complex water quality components, high COD and BOD concentrations, high ammonia nitrogen concentration, and many types of organic matter; based on the above characteristics, the treatment of landfill leachate needs to combine various technical means to meet the requirements of the new discharge standards. [0003] Among them, the common technologies for removing ammonia nitrogen are deammonization tower, nitrif...

AI Technical Summary

Problems solved by technology

[0003] Among them, the common technologies for removing ammonia nitrogen are deammonization tower, nitrification and denitrification deammonization biofilm, and electrolysis. The metabolism of microbial flora is greatly affected by changes in water quality, which in turn affects the treatment efficiency. However, the electrolysis method is limited in scope of use because of its single electrolyte and high energy consumption for electrolysis.

[0004] The common technical methods for deep oxidation to remove COD include the Fenton method and the ozone oxidation method. The Fenton method needs to be carried out in a strong acid environment, which requires high equipment materials, and at the same time produces more physical and chemical sludge, and the treatment cost is higher. ; and because of its limited treatment efficiency and relatively high energy consumption, the use of the ozone oxidation method is also subject to certain restrictions.

[0005] Biochemical treatment after proper pretreatment is also one of the landfill leachate treatment methods, but the traditional activated sludge microbial agent may have insufficient impact resistance or low metabolic efficiency, resulting in post-treatment The effluent does not meet the new discharge standards