Method for starting short-cut nitrification sludge micro-expansion under condition of low carbon-nitrogen ratio domestic sewage

Abstract

The invention discloses a method for starting short-cut nitrification sludge micro-expansion under the condition of low carbon-nitrogen ratio domestic sewage, and belongs to the technical field of biological sewage treatment. The method includes inoculating short-cut nitrification sludge in the SBR reactor; domesticating for 7 days to recover the activity, wherein the SVI is 60-80ml / g; starting short-cut nitrification sludge micro-expansion: performing continuous aeration in the first-stage single-cycle operation mode with low dissolved oxygen (DO concentration is 0.5 + / -0.1 mg / L), the aerobic time being 150-210 min, finishing aeration at the ammonia valley point, namely dissolved oxygen suddenly rises, enabling the nitrite accumulation rate to be larger than 85% after operation for 25 days and be kept stable, and entering the second stage; performing intermittent aeration in the second state, performing single-period oxygen deficiency and aerobic alternate operation for three times,wherein the ratio of oxygen deficiency to aerobic is 30: 60 min, stably keeping the short cut nitrification sludge micro-expansion state after operation is performed for 30 days, and controlling SVI to be 180-230 ml / g. Under the condition of low dissolved oxygen, low-carbon-nitrogen-ratio domestic sewage serves as inlet water, short-cut nitrification sludge micro-expansion can be started and stably maintained, the total nitrogen and COD removal rate of outlet water is increased, the water quality of the outlet water is improved, and the aeration rate and a carbon source are saved.

Description

Technical field: [0001] The invention relates to the field of sewage biological treatment, and provides a device and method for starting short-range nitrification sludge micro-expansion under the condition of low carbon-to-nitrogen ratio domestic sewage, which can start and maintain the state of sludge micro-expansion coupled with short-range nitrification for a long time, and improve total nitrogen and COD removal efficiency, save aeration and energy consumption, provide a short-range nitrification sludge micro-expansion start-up scheme for energy saving and consumption reduction for actual sewage treatment plants. Background technique: [0002] Activated sludge process is currently the most widely used sewage treatment technology in the world, but sludge bulking has always been a common problem in the operation of activated sludge process sewage treatment plants, and in severe cases, the sewage treatment system will collapse. Most of the activated sludge bulking problems a...

AI Technical Summary

Problems solved by technology

At present, domestic and foreign researches on sludge micro-expansion and short-range nitrification have achieved certain results. There are still few studies on the control of sludge bulking by quantitatively starting short-range nitrification sludge micro-expansion, especially the lack of precise control of the micro-expansion state of short-range nitrification sludge in combination with the physiological characteristics of filamentous bacteria and short-range nitrification conditions, so as to improve effluent water quality and save energy. consumption purpose

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