CN103623692B - A kind of method of blanket waste gas biofiltration device and process waste gas thereof - Google Patents

Abstract

The invention discloses a blanket-type waste gas biological filter device and a method for treating waste water. The filter device comprises a nutrient solution spray room, a packing room, a nutrient solution recovery room, an air inlet, an exhaust port, an induced draft fan, a pressure Pump, nutrient solution inlet, nutrient solution outlet and nutrient solution collection pool, the upper end of the blanket type waste gas biological filter device is a nutrient solution spray room, the lower end of the blanket type waste gas biological filter device is a nutrient solution recovery room, and the packing chamber Located between the nutrient solution spray room and the nutrient solution recovery room; the packing room hangs several pieces of blanket-type porous packing vertically, and the surface of the packing is inoculated with activated sludge or microorganisms for waste gas treatment, and the thickness of the blanket-type porous packing is 1 ～100mm, the horizontal distance between the adjacent blanket-type porous fillers is 1～10mm; the present invention has the advantages of simple operation and low energy consumption, and solves the problem of filler blockage in traditional biological filtration technology. When the space velocity is 0.07m/s, the unit The pressure drop of packing height has been kept stable within 400Pa/m.

Description

A blanket type waste gas biological filter device and method for treating waste gas

(1) Technical field

The invention relates to a waste gas treatment device and a method for treating waste gas, in particular to a blanket-type waste gas biological filter device and a method for treating waste gas, which can remove various pollutants such as hydrogen sulfide, ammonia and volatile organic compounds, and are suitable for Treatment of industrial waste gas, garbage and sewage odor.

(2) Background technology

Due to the advantages of low cost and environmental friendliness that cannot be compared with traditional methods (such as absorption, adsorption, combustion, etc.), waste gas biological treatment technology has gradually become a high-tech that is rapidly promoted in the field of waste gas purification, especially in low concentration, relatively high Large amount of organic waste gas and malodorous gas treatment. Compared with some developed countries abroad, although our country has a certain research foundation, its practical application is still in its infancy.

At present, there are three main types of research and application of gaseous pollutant biological treatment technology, namely biological scrubber, biological filter and biological trickling filter. These technologies have their own characteristics. For example, the biological washing tank has good absorption, but the biomass per unit volume is small and the treatment load is low, so it has been seldom used at present; Gas purification) does not need to spray nutrient solution, the equipment is simple, the processing capacity is large, and the management and maintenance are convenient, but the artificial control is poor, the pressure loss is large, and the service life is short; the biological trickling filter (currently generally used in industrial waste gas purification) can pass Nutrient solution circulation adjusts nutrients in time, has strong controllability and high processing load, and is especially suitable for volatile organic compounds that are difficult to degrade, but there are problems such as packing bed and circulation system blockage.

Generally speaking, the pressure drop of the packing layer of biological filtration technology is mainly related to the space velocity in the waste gas refilter tank. The higher the space velocity, the greater the pressure drop, so the higher the power of the induced draft fan required for air supply, the lower the energy consumption loss. bigger. At the same time, with the operation of the biofilter, the microorganisms attach to the filler to form a biofilm, and the microorganisms decompose the pollutants in the exhaust gas while performing metabolism and adding value. At this time, the biofilm will become thicker and thicker, resulting in narrower and narrower air passages. As the air velocity increases, the pressure loss will also increase accordingly. Microorganisms will age and die after growing for a certain period of time, and the dead biofilm will fall off from the filler. Since the fillers of traditional biofiltration technology are basically scattered in the biofilter, and the gaps are relatively small, this will cause the shedding biofilm to accumulate in the gaps of the fillers, thereby blocking the fillers, causing the gas channels to be further reduced and increasing the pressure loss. increase. If the exfoliated biofilm is not treated, the designed gas flow rate cannot meet the design and actual treatment requirements due to the large pressure drop of the packing layer.

How to overcome the defects such as bed blockage of traditional biological filtration technology, and explore a new generation of more advantageous biological treatment technology has become the starting point of the present invention.

During the operation of the biological filter, the plugging of the filler not only increases the pressure loss of the filter, but also reduces the amount of exhaust gas actually processed, thus affecting the actual project operation effect. In actual operation, it is necessary to regularly clean the packing or remove the biofilm on the packing by mechanical means, which makes the engineering operation difficult. In order to solve a series of problems caused by packing blockage, the present invention has developed a new type of blanket biofiller that can solve the problem of packing blockage. The air flow can not only diffuse vertically but also horizontally. The gaps between the fillers fall into the bottom of the filter tank, thus avoiding the accumulation of biofilm on the fillers and blocking the fillers.

(3) Contents of the invention

The purpose of the present invention is to provide a blanket-type waste gas biological filter device and its method for treating waste gas, which solves the problems of large pressure loss and unstable operation caused by stuffing blockage in traditional waste gas biological filter technology.

The technical scheme adopted in the present invention is:

The invention provides a blanket-type waste gas biological filter device, which includes a nutrient solution spray room, a packing room, a nutrient solution recovery room, an air inlet, an exhaust port, an induced draft fan, a pressure pump, a nutrient solution inlet, a nutrient solution Liquid outlet and nutrient solution collection pool, the upper end of the blanket-type waste gas biological filter device is a nutrient solution spray room, the lower end of the blanket-type waste gas biological filter device is a nutrient solution recovery room, and the packing room is located between the nutrient solution spray room and Between the nutrient solution recovery rooms; the top of the nutrient solution spray room is provided with an exhaust port, the side is provided with a nutrient solution inlet, and the interior is provided with a spray system; the side of the nutrient solution recovery room is provided with an air inlet and a nutrient solution outlet, the air inlet communicates with the induced draft fan through the pipeline, the outlet of the nutrient solution communicates with the nutrient solution collection pool, the nutrient solution collection pool communicates with the nutrient solution inlet through the pressure pump, and the nutrient solution inlet communicates with the spray The system is connected, and several pieces of blanket-type porous fillers are vertically suspended in the filler chamber, and the surface of the fillers is inoculated with activated sludge or microorganisms for waste gas treatment. The thickness of the blanket-type porous fillers is 1-100mm, and the adjacent blanket-type porous fillers The horizontal spacing is 1-10mm.

Further, the pore diameter of the blanket-type porous filler is 2-10 mm.

Further, the horizontal distance between adjacent blanket-type porous fillers is 2-5 mm.

Furthermore, the thickness of the blanket-type porous filler is 10-20 mm.

Further, the blanket-type porous filler is a net made of organic polymer materials with a pore size of 2-10 mm (preferably a net-like blanket-type porous filler woven with nylon or polyurethane), and the specific gravity of the filler is 0.65-1.28 g/cm ³ .

Furthermore, the aspect ratio of the packing chamber is (1-4):1.

Further, crossbeams are respectively set at the contact between the packing chamber and the nutrient solution spray chamber and the nutrient solution recovery chamber and the middle part of the packing chamber, and the top of the blanket packing is fixed on the crossbeam at the contact place between the packing chamber and the nutrient solution spray chamber Above, the bottom end of the blanket filler is fixed on the beam at the contact between the filler chamber and the nutrient solution recovery chamber, and the middle of the blanket filler is fixed on the beam in the middle of the filler chamber.

Further, the air inlet is located at the upper part of the nutrient solution recovery chamber, 0.2-2m away from the bottom end of the nutrient solution recovery chamber, the nutrient solution outlet is 0-0.5m away from the nutrient solution recovery chamber bottom end, and the nutrient solution inlet is 0-0.5m away from the nutrient solution inlet The top of the spray room is 0.3~1.5m.

The present invention also provides a method for treating waste gas by using the blanket-type waste gas biological filter device, the method is: open the induced draft fan, and the waste gas (preferably the waste gas containing xylene, the concentration of xylene is 1500-2000mg/m ³ ) passes through The induced draft fan enters the blanket-type exhaust gas biological filtration device, flows through the packing chamber and is discharged from the exhaust port, and at the same time, the pressure pump is turned on to spray the nutrient solution in the nutrient solution collection pool into the filling chamber through the nutrient solution spray system, and the nutrient solution flows into the filling chamber through the packing chamber The nutrient solution recovery chamber at the lower end of the exhaust gas biological filtration device enters the nutrient solution collection pool through the nutrient solution outlet; the ratio of the nutrient solution spray flow to the exhaust gas flow is (1-30): 10000, and the nutrient solution contains N, Mixture of inorganic compounds of P and organic compounds of C, H, and O. Preferably, the nutrient solution of the present invention is formulated with starch, ammonium chloride, and potassium hydrogen phosphate, with a starch concentration of 800 mg/L, a total phosphorus concentration of 6.8 mg/L, an ammonia nitrogen concentration of 90 mg/L, and a pH of 5.6-6.0.

Further, the ratio of the nutrient solution spray flow rate to the waste gas flow rate is (5-10):10000.

The exhaust gas of the present invention can enter from the bottom of the filter device and be discharged from the top, or can enter from one side of the lower end of the filter device and be discharged from the upper end of the other symmetrical side. The microorganisms decompose, and at the same time, the nutrient solution is sprayed from the upper part of the filter device to supply the metabolism of the microorganisms. The spraying nutrient solution flows through the packing chamber together with the microbial sludge that falls off from the packing and enters the nutrient solution recovery room, and then is discharged into the nutrient solution collection pool from the nutrient solution outlet. The microbial sludge in the nutrient solution collection pool needs to be cleaned regularly. The nutrient solution needs to be refreshed regularly.

The microorganisms attached to the filler come from the activated sludge inoculated at the initial stage of the operation of the biological filter, and the activated sludge is derived from microbial sludge or purely cultured microorganisms in urban sewage treatment plants or industrial wastewater biological treatment stations.

Compared with the prior art, the beneficial effects of the present invention are mainly reflected in: because the fillers in the traditional biofilter are scattered in the filter, the aged biofilm will fall from the gaps of the fillers to the bottom after falling off the fillers. On the filler, and accumulate on the top of the filler to gradually accumulate into a larger sludge mass, which eventually leads to the narrowing of the filler gap channel and complete blockage. The vertically suspended blanket-type porous filler inside the blanket-type biological filter device of the present invention has a large horizontal distance, and the shed biofilm directly falls from the filler gap to the bottom of the biological filter device and is discharged from the outlet of the absorbing liquid, which will not accumulate on the filler and cause blockage Fill voids or air channels. Therefore, the present invention has the advantages of simple operation and low energy consumption, and solves the problem of packing blockage in traditional biological filtration technology. When the air velocity is 0.07m/s, the pressure drop per unit packing height is always stable within 400Pa/m, equivalent to or even It is lower than the normal operating pressure of the current traditional biofiltration technology, and when the traditional biofiltration technology is clogged, the pressure drop can reach more than 4000pa/m (References 1-3, Document 1: Zhou Weilie, Wang Jiade, Zheng Rongqin, Chen Jianmeng. Research on biofilm formation process of tower packing and its characteristic parameters. Journal of Zhejiang University of Technology, 1999,27(4):300～305.

Document 2: Guo Bingbing, Wang Yuren, He Fengyou, Mou Guizhi. Medium-scale test of biological purification of malodorous waste gas from sewage treatment plants of petrochemical enterprises. Petroleum Refining and Chemical Industry, 2005, 36 (5): 66-70.

Document 3: Galina. Research on purification method of bio-trickling filtration of styrene organic waste gas. Dissertation of Qingdao University of Technology, 2006. ).

(4) Description of drawings

Figure 1 is a schematic diagram of the structure of the blanket-type exhaust gas biological filtration device: 1-nutrient solution spray room, 2-filler room, 3-nutrient solution recovery room, 4-air inlet, 5-exhaust port, 6-nutrient solution inlet, 7-nutrient solution outlet, 8-blanket packing, 9-spray system, 10-nutrient solution collection pool, 11-induced fan, 12-pressure pump.

(5) Specific implementation methods

The present invention is further described below in conjunction with specific embodiment, but protection scope of the present invention is not limited thereto:

Example 1:

Referring to Fig. 1, the blanket type waste gas biological filter device comprises a nutrient solution spray chamber 1, a packing chamber 2, a nutrient solution recovery chamber 3, an air inlet 4, an exhaust port 5, a nutrient solution inlet 6, a nutrient solution outlet 7 and Nutrient solution collection pool 10, the upper end of the blanket-type waste gas biological filter device is a nutrient solution spray room 1, the lower end of the blanket-type waste gas biological filter device is a nutrient solution recovery room 3, and the packing room 2 is located in the nutrient solution spray room and between the nutrient solution recovery chamber; the top of the nutrient solution spray chamber 1 is provided with an exhaust port 5, the side is provided with a nutrient solution inlet 6, and the interior is provided with a spray system 9; the nutrient solution recovery chamber 3 is provided with a side surface The air inlet 4 and the nutrient solution outlet 7, the air inlet 4 communicates with the induced draft fan 11 through the pipeline, the nutrient solution outlet 7 communicates with the nutrient solution collection pool 10, and the nutrient solution collection pool 10 passes through the pressure pump 12 It communicates with the nutrient solution inlet 6, the nutrient solution inlet 6 communicates with the spray system 9, the packing chamber 2 hangs two blanket-type porous packing 8 vertically, the material is polyurethane, and the surface of the packing is inoculated with activated sludge or waste gas treatment With microorganisms, the inoculation method is as follows: after the microorganisms to be inoculated or the activated sludge of urban sewage plants are poured into the nutrient solution collection tank with an inoculum volume of 2g/L filler volume, the microorganisms and nutrients in the nutrient solution collection tank are collected by a lift pump. The liquid is fed into the biological filter device together. Stainless steel beams are respectively set at the contact between the packing chamber and the nutrient solution spray chamber and the nutrient solution recovery chamber and the middle part of the packing chamber, and the top of the blanket packing is fixed on the crossbeam at the contact place between the packing chamber and the nutrient solution spray chamber , the bottom end of the blanket packing is fixed on the crossbeam at the contact between the packing chamber and the nutrient solution recovery chamber, and the middle of the blanket packing is fixed on the crossbeam in the middle of the packing chamber.

The effective volume of the packing chamber of the blanket-type biological filter device is 20L, the thickness of the blanket-type porous filler is 50mm, the vertical length is 1m, the lateral length is 0.2m, and the horizontal distance between the adjacent blanket-type porous fillers is 2mm; The air inlet is located at the upper part of the nutrient solution recovery chamber, 0.2m away from the bottom end of the nutrient solution recovery chamber, the nutrient solution outlet is 0.02m away from the bottom end of the nutrient solution recovery chamber, and the nutrient solution inlet is 0.3m away from the top of the nutrient solution spray chamber; The spraying system is composed of pipes and nozzles, the nozzles are DN15 perforated pipes made of polypropylene, and the distance from the top of the stuffing chamber is 0.2m. Nutrient solution collection pool length × width × height: 0.3m × 0.3m × 0.4m.

The method of treating waste gas: turn on the induced draft fan, the waste gas enters the blanket type waste gas biological filter device through the induced draft fan, flows through the packing chamber and is discharged from the exhaust port, and at the same time turns on the pressure pump to pass the nutrient solution in the nutrient solution collection pool through the nutrient solution spray system Spray into the filling chamber, the nutrient solution flows into the nutrient solution recovery chamber at the lower end of the waste gas biological filter through the filling chamber, and then enters the nutrient solution collection pool through the nutrient solution outlet; the ratio of the nutrient solution spray flow to the exhaust gas flow is 3:10000, The nutrient solution is made of starch, ammonium chloride, and potassium hydrogen phosphate. The starch concentration is 800mg/L, the total phosphorus is 6.8mg/L, the ammonia nitrogen concentration is 90mg/L, and the pH is 5.6-6.0. The nutrient solution collection pool The nutrient solution in the bottle is renewed by 2000ml every day.

The exhaust gas to be purified in the test is the exhaust gas containing xylene, and the concentration of xylene is 1500-2000 mg/m ³ . The test results are shown in Table 1. During the operation of the blanket biological filter device, the intake flow rate and processing load are increased according to the xylene treatment efficiency. The xylene treatment load is controlled at 20g/(m ³ h) at the initial stage of startup, and the nutrient solution spray flow rate is 0.26L/h , the ratio of the nutrient solution spray flow rate to the exhaust gas flow rate is 1:1000, when the xylene removal rate reaches over 90%, the gas flow rate increases by 50% (that is, the gas flow rate is 390L/h, and the nutrient solution spray flow rate is 0.39L/h ); when the xylene treatment load reaches 40g/(m ³ h), the gas flow rate increases by 30% as the xylene removal rate reaches 90% (that is, the gas flow rate is 520L/h, and the nutrient solution spray flow rate is 0.52L/h h); when the xylene treatment load reaches 60-75g/(m ³ h), normal operation starts. At this time, the gas flow rate is 780L/h, the nutrient solution spray flow rate is 0.78L/h, and its operating performance Make an evaluation. After 6 months of start-up and operation, the xylene removal rate is stable at 90%-92%, the pressure difference is stable within 220pa, and the xylene concentration in the exhaust gas is 120-200mg/m ³ .

Compared with the existing biological filtration technology, the above research results show that under the same air velocity, removal efficiency and treatment load, the pressure difference of the biological filtration device is basically stable within 220pa/m, lower than the traditional biological filtration technology, and there is no filler clogging phenomenon.

Table 1 Experimental test data

Claims (7)

1. a blanket waste gas biofiltration device, described filter comprises nutrient solution spray chamber, filler chamber, nutrient solution recovery room, air inlet, exhaust outlet, nutrient solution entrance, air-introduced machine, compression pump, nutrient solution outlet and nutrient solution collecting pit, the upper end of described blanket waste gas biofiltration device is nutrient solution spray chamber, the lower end of blanket waste gas biofiltration device is that nutrient solution reclaims room, and described filler chamber reclaims between room at nutrient solution spray chamber and nutrient solution, described nutrient solution spray chamber top is provided with exhaust outlet, and side is provided with nutrient solution entrance, and inside is provided with spray system, described nutrient solution reclaims side, room and is provided with air inlet and nutrient solution outlet, described air inlet is communicated with air-introduced machine by pipeline, described nutrient solution outlet is communicated with nutrient solution collecting pit, described nutrient solution collecting pit is by compression pump and nutrient solution inlet communication, described nutrient solution import communicates with spray system, it is characterized in that described filler chamber vertical hanging some blocks of blanket porous aggregates, described filling surface inoculation of activated-sludge or exhaust-gas treatment are with microorganism, described blanket porous aggregate is aperture is net prepared by 2 ~ 10mm high-molecular organic material, filler proportion is 0.65 ~ 1.28g/cm ³, described blanket porous aggregate thickness is 1 ~ 100mm, and described adjacent blanket porous aggregate level interval is 1 ~ 10mm.

2. blanket waste gas biofiltration device as claimed in claim 1, is characterized in that described adjacent blanket porous aggregate level interval is 2 ~ 5mm.

3. blanket waste gas biofiltration device as claimed in claim 1, is characterized in that described blanket porous aggregate thickness is 10 ~ 20mm.

4. blanket waste gas biofiltration device as claimed in claim 1, it is characterized in that the middle part that described filler chamber and nutrient solution spray chamber and nutrient solution reclaim contact position, room and filler chamber arranges crossbeam respectively, the top of described blanket filler is fixed on the crossbeam of filler chamber and nutrient solution spray chamber contact position, the bottom of described blanket filler is fixed on filler chamber and nutrient solution reclaims on the crossbeam of contact position, room, and the centre of described blanket filler is fixed on the crossbeam of filler chamber middle part.

5. blanket waste gas biofiltration device as claimed in claim 1, it is characterized in that described air inlet is positioned at nutrient solution and reclaims top, room, distance nutrient solution reclaims bottom, room 0.2 ~ 2m, described nutrient solution outlet distance nutrient solution reclaims bottom, room 0 ~ 0.5m, described nutrient solution entrance distance nutrient solution spray chamber top 0.3 ~ 1.5m.

6. one kind utilizes the method for blanket waste gas biofiltration device process waste gas described in claim 1, it is characterized in that described method is: open air-introduced machine, waste gas enters blanket waste gas biofiltration device by air-introduced machine, flow through filler chamber and discharged by exhaust outlet, nutrient solution in nutrient solution collecting pit is sprayed onto filled chamber by nutrient solution spray system by opening pressure pump simultaneously, the nutrient solution of nutrient solution through filler chamber's inflow exhaust gas biofiltration device lower end reclaims indoor, then enters nutrient solution collecting pit by nutrient solution outlet; The ratio of described nutrient solution spray flow and exhaust gas flow is 1 ~ 30:10000, and described nutrient solution contains the inorganic compound of N, P and the mixing liquid containing C, H, O organic compound.

7. the method for blanket waste gas biofiltration device process waste gas as claimed in claim 6, other are that the ratio of described nutrient solution spray flow and exhaust gas flow is 5 ~ 10:10000.