CN102060416A

CN102060416A - Method for treating low-temperature city sewage by using anoxic-oxic moving bed biomembrane reactors

Info

Publication number: CN102060416A
Application number: CN2010105681082A
Authority: CN
Inventors: 孙德智; 张立秋; 马华敏
Original assignee: Beijing Forestry University
Current assignee: Beijing Forestry University
Priority date: 2010-12-01
Filing date: 2010-12-01
Publication date: 2011-05-18

Abstract

The invention belongs to the field of city sewage treatment and relates to a method for treating low-temperature city sewage by using anoxic-oxic moving bed biomembrane reactors, comprising the specific steps of: (1) introducing the low-temperature city sewage to the anoxic moving bed biomembrane reactor for anoxic reaction; (2) after anoxic reaction, introducing the sewage to a settling tank 1, settling, and then introducing the discharged water to the oxic moving bed biomembrane reactor; (3) introducing the discharged water to a settling tank 2 after oxic reaction for a certain time; and (4) after settlement, introducing the discharged water to a water discharging tank, directly discharging part of the sewage in the discharged water, and introducing the other part of the sewage to an anoxic reaction tank for denitrification treatment according to a certain reflux ratio. City sewage can be effectively treated with the process under the low temperature of 8 DEG C. Compared with other treatment technologies, the method has the advantages of no sludge discharging for long time, small occupied area and strong removing capability for organic matters, ammonia nitrogen, total nitrogen and total phosphorus and the like.

Description

A kind of method of utilizing anaerobic-aerobic MBBR combination process to handle the low temperature municipal effluent

One, technical field

The present invention relates to a kind of method that is applicable to municipal sewage treatment under the cold condition.

Two, background technology

The processing of cold district low-temperature sewage is the difficult point in the present water treatment always.Because the most of the time in high latitude cold district winter is in low temperature environment, the land drainage temperature is generally at 6～12 ℃ (minority is at 5～9 ℃), the processing efficiency that is arranged at outdoor sewage biochemical treatment facility significantly reduces, and it is up to standard to cause effluent of municipal sewage plant water quality to be difficult to.After sewage not up to standard entered near river, city, the pollution load total amount that makes river bear was compared other seasons and is improved greatly, and ice-bound season in winter, the self-purification capacity of river is almost lost, and water quality of river has been caused very big influence.

In recent years, obtained attention gradually, had broad application prospects for microbic activity research under the low temperature and in Application of Sewage.Advantage is subjected to extensive concern to MBBR because of having that biomass is big, the anti impulsion load ability is strong, processing power is high, energy consumption is low and maintenance management is simple etc.At present carried out a large amount of research at moving-bed biofilm technology abroad, generally obtained good effect, mechanism and the influence factor to organic removal and denitrogenation dephosphorizing had more deep understanding simultaneously.The present invention is combined as anoxic-aerobic process with MBBR, when reactor is efficiently removed organism and ammonia nitrogen, also possessed the ability of removing total nitrogen, made water outlet after the processing reach the one-level A standard (" urban wastewater treatment firm pollutant emission standard (GB18918-2002) ") of national requirements discharging.Therefore, use anaerobic-aerobic MBBR processing low temperature municipal effluent that the promotion and application of cold district sewage disposal technology are had great importance.

Three, summary of the invention

The present invention be directed to the characteristics of freezeup period in winter municipal effluent, propose a kind of method that is applicable to municipal sewage treatment under the cold condition,, make effluent quality meet one-level A emission standard to solve the problem of biochemical treatment weak effect under low temperature condition.

Concrete technical process is as follows:

1, send into anoxic moving-bed biofilm reaction tank from the equalizing tank lifting sewage, water outlet enters settling tank 1 behind the hypoxia response;

2, through the post precipitation of 2h in settling tank 1, water outlet enters aerobic moving bed biomembrane reaction pond, and water outlet enters settling tank 2 behind the aerobic reaction;

3, the post precipitation of 2h in settling tank 2, water outlet enters outlet sump, directly discharging of a sewage part in the outlet sump, another part is back to anoxic moving-bed biofilm reaction tank with 200% ratio, carries out denitrogenation processing.

The present invention can be under 8 ℃ cold condition, effective Treating Municipal Sewage, compare with other treatment technologies have for a long time not spoil disposal, floor space is little, to advantages such as removal abilities such as organism, ammonia nitrogen, total nitrogen and total phosphorus are strong.

The explanation of accompanying drawing table

Fig. 1 is the process device figure of invention;

Specific embodiments

Embodiment one:

Come the present invention is further detailed below in conjunction with concrete embodiment.

This example is for adopting certain city, art breading of the present invention north low-temperature sewage in winter.The sewage quality feature sees Table 1.

Certain city sewage quality in winter feature of table 1

1, at first sewage extracts in the equalizing tank and delivers to anoxic moving-bed biofilm reaction tank, is provided with agitator in the pond, makes nitrate, nitrite denitrification become nitrogen in anoxic pond, and the residence time is 4h, and behind the hypoxia response, water outlet enters settling tank 1;

2, through the 2h post precipitation, water outlet enters aerobic moving bed biomembrane reaction pond, be provided with aerating pipelines at the bottom of the pond, for guaranteeing the efficient removal of total nitrogen, at aerobic stage, dissolved oxygen concentration is adjusted at below the 3mg/L, nitrifying process is controlled at the nitrite stage, and to realize short distance nitration in anoxic pond, the pool inner water power residence time is 8h, water outlet enters settling tank 2 behind aerobic reaction, and sedimentation time is 2h.According to the variation of influent quality, the mud intermittences 100% in the settling tank 1,2 are back to hypoxia response pond and aerobic reaction pond, to guarantee when influent load is big competent biomass in two ponds;

3, the water outlet of post precipitation enters outlet sump, and a sewage part is back to the hypoxia response pond with 200% reflux ratio and carries out denitrogenation processing in the outlet sump, and a part is directly discharged, and except that water inlet and refluxing, all relies on the gravity water outlet between each reactor.The polyethylene filler that is mixed with the inorganic active particle all is housed in anoxic pond and Aerobic Pond, and the filler packing ratio is 50% in the anoxic pond, and the filler packing ratio is 40% in the Aerobic Pond, for preventing overflowing of filler, is provided with the filter of aperture less than filler at two Chi Chushuikouchu.

4, the equal spoil disposal not of experimental session two reactor cell, after biofilm is finished, microbial film thickness is even in the two pond fillers, even under the condition of 8 ℃ of low temperature, the aerobic speed of ratio (OUR) biological in the filler of aerobic moving bed biomembrane reaction pond on average still can reach 12.8mgDO/gMLSSh, and the denitrification rate to nitrate nitrogen and nitrite nitrogen in the anoxic pond can reach 0.94mgNO respectively ₃-N/gMLSSh and 13.35mgNO ₂-N/gMLSSh.After the steady running, reactor is to the COD in the sewage, NH _3-The clearance best result Bie Keda 95%, 98%, 75%, 93% and about 95% of-N, TN, TP, SS, COD, NH in the sewage water outlet after reactor for treatment ₃The content of-N, TN, SS all can reach the one-level A standard (" urban wastewater treatment firm pollutant emission standard (GB18918-2002) ") of national requirements discharging.

5, analytical procedure: COD, BOD ₅, NH ₃-N, TN, TP, SS measure and all adopt standard method.

Claims

1. method that effectively is used for the low temperature municipal sewage treatment, its feature mainly comprises the steps:

A, the low temperature municipal effluent is introduced in the anoxic MBBR, its inner suspension filler packing ratio is 50%, and hydraulic detention time is 4h; Sewage enters settling tank 1 and precipitates behind b, the hypoxia response, and sedimentation time 2h can prevent that anoxic mud from entering aerobic reactor, impacts aerobic reaction; C, enter aerobic moving bed biofilm reactor through oettIed sewage, its inner suspension filler packing ratio is 40%, and hydraulic detention time is 8h, by adjusting the nitrated final product of dissolved oxygen concentration control in the pond; Water outlet enters settling tank 2 behind d, the aerobic reaction, and sedimentation time is 2h, and post precipitation mud can be selected discharging or backflow according to influent load; E, post precipitation water outlet enter outlet sump, and a sewage part is directly discharged in the outlet sump, and another part enters the hypoxia response pond with 200% reflux ratio and carries out denitrogenation processing.

2. be combined as anoxic-aerobic process according to claim 1 described use MBBR, it is characterized in that according to the MBBR biomass big, microorganism growth is long generation time, and active higher characteristics, be suitable for handling low-temperature sewage, the adding of anoxic pond makes reactor remove the organic denitrogenation ability that has simultaneously.

3. according to claim 1 described settling tank 1 and the settling tank 2 of behind anoxic and aerobic moving bed biofilm reactor, being provided with respectively, it is characterized in that and to descend in temperature, when microorganism active reduction or influent load are big, guarantee competent biomass in two ponds by the mud backflow, so that sewage is effectively handled.

4. according to controlling final nitration product by adjusting dissolved oxygen concentration in the claim 1 described aerobic moving bed reaction tank, it is characterized in that, under the cold condition, denitrification rate obviously slows down, and when organic concentration in the water inlet is low, can save the usage quantity of aeration rate and carbon source simultaneously by realizing that short distance nitration improves nitrogen removal rate.

5. according in claim 1 described anoxic and the aerobic moving bed biomembrane reaction pond floating stuffing being housed all, compare other fillers, specific surface area is bigger, and total specific surface area is about 900m ²/ m ³, and have microvoid structure through the biologic packing material of modification, help the absorption of microorganism and pollutent.