Kitchen garbage slurry anaerobic fermentation wastewater treatment method

Abstract

The invention relates to a kitchen garbage slurry anaerobic fermentation wastewater treatment method, in particular to a treatment method for treating wastewater produced in other procedures through wastewater produced after anaerobic fermentation dehydration of kitchen garbage slurry and kitchen garbage. Wastewater is subjected to oil-separation primary precipitation, water amount and water quality adjustment, first pH value adjustment, free ammonia stripping in an ammonia stripping tower, second pH value adjustment, A/O biochemical treatment, precipitation treatment, treatment in a Fenton reactor and treatment in a coagulative precipitation tank, so that pollutants such as COD, BOD5 and SS in the wastewater are removed, TN and TP can be removed effectively, the wastewater chroma can be lowered effectively, the TN and TP removing rates are increased, and pollutants such as COD, BOD5, TN, NH3-N, TP and chroma in the treated wastewater can stably meet the requirements in Integrated Wastewater Discharge Standard (GB8978-1996, grade III standard) and Wastewater Quality Standards for Discharge to Municipal Sewers (GB/T 31962-2015, grade B).

Description

technical field [0001] The invention relates to a method for treating kitchen waste wastewater, in particular to a treatment method for waste water after anaerobic fermentation and dehydration of kitchen waste slurry and waste water produced in other processes of kitchen waste treatment, and belongs to the field of sewage treatment. Background technique [0002] Wastewater after anaerobic fermentation and dehydration of food waste slurry, as well as waste water generated by other processes of food waste treatment, has complex components and is a high-concentration organic wastewater that is difficult to treat. The concentration of pollutants in wastewater is high, chemical oxygen demand (COD, 8000-20000mg / L), biochemical oxygen demand (BOD 5 , 4000~8000mg / L), total nitrogen (TN, 2000~3000mg / L), ammonia nitrogen (NH 3 -N, 1500~2500mg / L), total phosphorus (TP, 50~150mg / L), suspended solids (SS, >8000mg / L), salt content (15000~30000mg / L), animal and vegetable oil (800~1500m...

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Problems solved by technology

[0004] In the prior art, there is a method called "treatment method of secondary waste water from kitchen waste", which is a combined process of "pretreatment + anaerobic + aerobic + flocculation and sedimentation". The operation and management requirements are high, especially the anaerobic treatment process consumes the carbon source in the wastewater, which further reduces the carbon-nitrogen ratio in the wastewater (COD, BOD 5 decrease, ammonia nitrogen increases), the reduction of carbon-nitrogen ratio is more unfavorable to the biological denitrification of wastewater; second, the ammonia nitrogen in wastewater mainly undergoes nitrification reaction in the aerobic stage and is converted into nitrate nitrogen and nitrite nitrogen. than (BOD 5 : TKN) was lowered at a lower level, resulting in a lack of carbon sources. Because there is no sufficient carbon source, denitrification and denitrification cannot be completed, and the total nitrogen cannot be effectively degraded and removed, and the total nitrogen removal rate is low. It is difficult to meet the requirements of the "B grade" standard in the "Water Quality Standards for Discharge of Sewage into Urban Sewers" (GB / T 31962-2015)

[0005] In the prior art, there is also a method called "kitchen waste wastewater treatment method". The steps include: first pretreatment to remove solid impurities, oil, sticky matter, etc. in the wastewater, and then pass through the anaerobic biofilm reactor respectively. , The aerobic biofilm reactor acidifies and removes the organic matter in the wastewater, and finally discharges it after being treated by the reverse osmosis membrane; The disadvantages are that, one is that the anaerobic treatment process unit in this method has the same problem as the anaerobic treatment process unit in the above-mentioned "treatment method of kitchen waste secondary wastewater"; the other is that the reverse osmosis membrane used in this method Although the treatment technology can meet the requirements of the "B-level" standard of "Water Quality Standards for Sewage Discharge into Urban Sewers", its disadvantages are: the oil in the wastewater can easily cause membrane blockage, and the high salt in the wastewater will accelerate the aging of the membrane. The lifespan is short, especially membrane technology is a physical filtration technology, which only intercepts the pollutants in the wastewater, but does not really degrade the pollutants. Secondary pollution and higher operating costs

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