CN101746889B

CN101746889B - Method for reducing sludge of aerobic unit in activated sludge and sewage treatment process

Info

Publication number: CN101746889B
Application number: CN200810207463XA
Authority: CN
Inventors: 仓一华; 郭志宏; 赵海云; 吴培云; 吴敏
Original assignee: Sinopec Shanghai Petrochemical Co Ltd
Current assignee: Sinopec Shanghai Petrochemical Co Ltd
Priority date: 2008-12-19
Filing date: 2008-12-19
Publication date: 2011-08-31
Anticipated expiration: 2028-12-19
Also published as: CN101746889A

Abstract

The present invention relates to a method for reducing sludge of an aerobic unit in an activated sludge and sewage treatment process comprising the following steps: a chemical uncoupler is added in inlet water of the aerobic unit. The chemical uncoupler is a composition which comprises components of 3,3',4',5-tetrachloro salicylanilide and zeolite. The weight ratio of the 3,3',4',5-tetrachloro salicylanilide and the zeolite is 1: (0.1-1.5). The adding amount of the chemical uncoupler in the inlet water is controlled at 1-4mg/l according to the 3,3',4',5-tetrachloro salicylanilide. The method has obvious positiveeffects that the sludge reduction effect is better, the added TCS can be reduced by 20-60% for achieving the same sludge reduction rate, and the COD removal rate is not affected.

Description

The method of reducing sludge of aerobic unit in activated sludge and sewage treatment process

Technical field

The present invention relates to a kind of method that reduces excess sludge yield of aerobic unit in activated sludge and sewage treatment process, this method is by adding chemical uncoupler in the aerobic unit water inlet, reduce the productive rate of activated sludge sewage disposal process aerobic unit excess sludge with the uncoupling method, reach the purpose of aerobic unit mud decrement.

Background technology

Activated sludge process is present most widely used sewage (comprising a municipal effluent or industrial sewage) biologic treating technique, though this Technology has a lot of advantages, few as initial cost, treatment effect is good, stable etc., but also there is a significant disadvantage in it, promptly can produce a large amount of excess sludges in operational process.The processing cost of excess sludge is quite high, generally can account for 25%～65% of Sewage Plant operation total expenses, and therefore, the production rate that activated sludge sewage disposal process reduces or reduce excess sludge is the problem of being paid close attention to very much always.According to different sewage qualities, concrete active sludge treatment process has multiple unit and makes up, and excess sludge mainly results from aerobic unit.Existing commonly used mud decrement technology comprises that mainly extended aeration process, pure-oxygen aeration method, microorganism predation method, aerobic or anaerobic digestion conciliate coupling method etc., although these methods all exist tangible advantage and deficiency separately, but comparatively speaking, wherein the uncoupling method is not because of increasing or do not change the unit combination of original technology, it is convenient to implement, especially reduce the amplitude maximum of sludge yield, thereby be most widely used and have more development prospect.

In activated sludge process, microorganism is pollutent to be removed from waste water as the carbon source and the energy of growth with pollutants in waste water matter (matrix), obviously microorganism growth is relevant with the matrix utilization, and the synthetic energy that also needs to be coupled with it of microorganism to be to form new cell, and this energy is mainly provided by Triphosaden (ATP).ATP then mainly is that oxidation and the phosphorylation by adenosine diphosphate (ADP) (ADP) generates in the microbiological degradation metabolic process, under the normal circumstances, oxidizing reaction and phosphorylation reaction are link coupled, and promptly microorganism changes into simultaneous ADP in the process of pollution substance oxidation the phosphorylation process of ATP.The uncoupling method is to add chemical agent-uncoupling agents in system, makes the coupling relation broken that exists between oxidation and the phosphorylation, suppresses the carrying out of the phosphorylation reaction of generation ATP, thereby makes the microorganism anabolism reduce the purpose that reduces the microorganism productive rate to reach.

The performance of uncoupling agents is most important in the uncoupling method, and uncoupling agents commonly used in the prior art has 2,2, 4-dinitrophenol, Trichlorophenol, 2,4 dichloro phenol and 3,3 ', 4 ', 5-tetrachloro-salicylanilide (TCS) etc.Wherein TCS significantly uses the most extensive because of the decrement effect to excess sludge, in some active sludge treatment process, the multipotency of the output of mud reduces 40%, " Utilization ofa metabolic uncoupler 3 for example, 3 ', 4 ', 5-tetrachlorosalicylanilide (TCS) to reduce sludge growth in activated sludge culture " (Water Res, 2002,36 (8): 2077-2083) introduced in the literary composition.Although all uncoupling agentss all have a common shortcoming, can make the activity of mud reduce after the i.e. adding system, yet this shortcoming of TCS is more remarkable, " killing and wounding " effect to microorganism is bigger relatively, and this perhaps is that TCS can't thoroughly replace one of main reason of other uncoupling agents.

Summary of the invention

The invention provides a kind of method of reducing sludge of aerobic unit in activated sludge and sewage treatment process, it has adopted a kind of with 3,3 ', 4 ', 5-tetrachloro-salicylanilide (TCS) is the compound uncoupling agents of main component, can solve effectively in the prior art to cause sludge activity to reduce this technical problem because of TCS adds Sewage treatment systems.

Below be the technical scheme that the present invention solves the problems of the technologies described above:

A kind of method of reducing sludge of aerobic unit in activated sludge and sewage treatment process, this method comprise in aerobic unitary water inlet and add chemical uncoupler.This chemical uncoupler is a composition, and component comprises 3,3 ', 4 ', and 5-tetrachloro-salicylanilide and zeolite powder, 3,3 ', 4 ', the weight ratio of 5-tetrachloro-salicylanilide and zeolite powder is 1: (0.1～1.5).With 3,3 ', 4 ', 5-tetrachloro-salicylanilide meter, the add-on of chemical uncoupler is controlled to be 1～4mg/l in the water inlet.

By convention, above-mentioned aerobic unit comprises an aeration workshop section and a precipitation workshop section at least successively.Sewage prior in the aeration workshop section with the active sludge uniform mixing, sludge loading is controlled to be 0.3～6kgBOD ₅/ (kgMLVSSd), and aeration aerating in the aeration workshop section, dissolved oxygen is controlled to be 0.5～4mg/l, and the residence time of sewage in aeration workshop section is controlled to be 0.5～8hr, carries out mud-water separation subsequently in precipitation workshop section.

In the above-mentioned chemical uncoupler 3,3 ', 4 ', the weight ratio of 5-tetrachloro-salicylanilide and zeolite powder is preferably 1: (0.2～0.8); The granularity of chemical uncoupler mesolite powder is generally got 40～100 orders.

The present invention is suitable for any activated sludge process Sewage treatment systems that contains aerobic unit, as by single-stage or multistage aerobic unit, single-stage or multistage aerobic/system that the anaerobism alternate cells constitutes.

In aerobic unit, sewage and mud are not to be in the homogeneous admixture each other, although there is the mechanical agitation of aeration, mud serves as main being suspended in the system with micelle particulate form still.The contriver finds that in experiment TCS is very relevant in the concentration of aqueous phase with TCS to " killing and wounding " effect of microorganism, and concentration higher " killing and wounding " effect is bigger.The uncoupling of TCS is then very relevant with the concentration of TCS in mud micelle particle, and concentration heals high uncoupling more greatly.

Essence of the present invention is to have adopted a kind of compound uncoupling agents, it by TCS and zeolite powder according to a certain percentage mixed preparing form.The contriver observes in experiment, because zeolite powder has bigger porosity and specific surface, TCS is not only had stronger adsorption, and loading capacity is very big.When TCS with after zeolite powder mixes according to a certain percentage, zeolite powder is as the carrier TCS that adsorbed load, form the compound uncoupling agent of a kind of " loading type ", and be carried on the TCS meeting rapid " dissolving " in water and unlike simple TCS on " carrier ", and slowly discharge with relatively low speed, therefore the compound uncoupling agent of this " loading type " can be regarded as " slowly-releasing " TCS.The contriver finds by further experiment, compares with simple TCS, and the dissolution rate at sewage behind the TCS of this " loading type " input coefficient obviously slows down, and therefore the concentration at the sewage aqueous phase greatly reduces.On the other hand, gather fusedly because the zeolite powder particle is very easy with mud micelle particle, both gather fused back TCS and will discharge lentamente in " dissolving in " mud micelle, make can obtain higher TCS concentration in the mud micelle.

The mechanism that more than to be exactly the compound TCS uncoupling agents that adopts of the present invention can obviously reduce when keeping good mud decrement performance to the abated effect of sludge activity.So positively effect compared with prior art of the present invention is fairly obvious, is embodied in following 2 points:

1) effect of mud decrement is better, as reaches same mud decrement rate, and the TCS that adds can reduce 20～60%;

2) the COD clearance is unaffected substantially.

To come below that the present invention is further illustrated by specific embodiment, in an embodiment, the mud decrement rate is defined as:

Wherein, sludge yield I is the sludge yield that does not add uncoupling agents in the aerobic unit, and sludge yield II is the sludge yield that adds in the aerobic unit behind the uncoupling agents.

Because key of the present invention is the uncoupling agents that adopts is improved, and other technical process or parameter and prior art are basic identical, so embodiment will pay attention to enumerating of uncoupling agents composition and dosage thereof.

Embodiment

[embodiment 1～8]

The sewage of handling is oil refining sewerage, handles through oil removal, coagulation flotation, and the water quality of water inlet is:

COD 575mg/l

PH value 8.2

Adopt sequencing batch active sludge (SBR technology) to handle, reactor volume is 8m ³, operation comprises successively: water inlet-aerobic reaction-precipitate-strain water-anaerobism (moving in circles), and the operation process condition of aerobic reaction operation is:

Sludge loading 0.4～0.9kg BOD ₅/ (kgMLVSSd)

20～30 ℃ of temperature of reaction

Dissolved oxygen 2～4mg/l

The uncoupling agents add-on sees Table 1 in the sewage

(in TCS)

The uncoupling agents that each embodiment adopts is prepared in required ratio, and getting granularity is 40～100 purpose zeolite powders, and the weight ratio of TCS and zeolite powder sees Table 1.Uncoupling agents is stirred to formation suspension with service water earlier, and compound concentration is 2～4g/l, adds with water inlet then.

[embodiment 9～16]

The sewage of handling is the ethylene glycol production waste, and the water quality of water inlet is:

COD 2050mg/l

PH value 6～9

Adopt the AB Activated Sludge Process to handle, flow process comprises successively: water inlet-A section high loading aerobic treatment-intermediate sedimentation pond-B section underload aerobic treatment-final tank-draining, the part mud of intermediate sedimentation pond and final tank is back to each spontaneous Aerobic Pond, excess sludge discharge respectively.Embodiment 9～16 carries out mud decrement at the higher A section high loading aerobic unit (comprising A section high loading aerobic treatment and intermediate sedimentation pond) of sludge yield to be handled, and the operation process condition is:

Sludge loading 2～4kgBOD ₅/ (kgMLVSSd)

20～30 ℃ of temperature of reaction

Dissolved oxygen 0.5～1mg/l

Uncoupling agents add-on amount sees Table 1 in the sewage

(in TCS)

[comparative example 1]

Except that the uncoupling agents that uses was simple TCS, all the other were with embodiment 1～8.

[comparative example 2]

Except that the uncoupling agents that uses was simple TCS, all the other were with embodiment 9～16.

The experimental test of each embodiment and comparative example the results are shown in Table 2

Table 1.

Table 2.

Claims

1. the method for a reducing sludge of aerobic unit in activated sludge and sewage treatment process, this method comprises in aerobic unitary water inlet and adds chemical uncoupler, it is characterized in that this chemical uncoupler is a composition, component comprises 3,3 ', 4 ', 5-tetrachloro-salicylanilide and zeolite powder, 3,3 ', 4 ', the weight ratio of 5-tetrachloro-salicylanilide and zeolite powder is 1: (0.1～1.5), and with 3,3 ', 4 ', 5-tetrachloro-salicylanilide meter, the add-on of chemical uncoupler is controlled to be 1～4mg/l in the water inlet.

2. the method for reducing sludge of aerobic unit in activated sludge and sewage treatment process according to claim 1, it is characterized in that described aerobic unit comprises an aeration workshop section and a precipitation workshop section at least successively, sewage prior in the aeration workshop section with the active sludge uniform mixing, sludge loading is controlled to be 0.3～6kgBOD ₅/ (kgMLVSSd), and aeration aerating in the aeration workshop section, dissolved oxygen is controlled to be 0.5～4mg/l, and the residence time of sewage in aeration workshop section is controlled to be 0.5～8hr, carries out mud-water separation subsequently in precipitation workshop section.

3. the method for reducing sludge of aerobic unit in activated sludge and sewage treatment process according to claim 1 and 2 is characterized in that in the described chemical uncoupler 3,3 ', 4 ', and the weight ratio of 5-tetrachloro-salicylanilide and zeolite powder is 1: (0.2～0.8).

4. the method for reducing sludge of aerobic unit in activated sludge and sewage treatment process according to claim 1 and 2, the granularity that it is characterized in that described chemical uncoupler mesolite powder is 40～100 orders.