CN102336503A - Biological membrane-photocatalytic integration reaction device for micro pollution raw water pretreatment - Google Patents

Abstract

The invention relates to a biofilm-photocatalytic integrated reaction device for pretreatment of slightly polluted raw water. The biofilm biochemical reaction area and the photocatalytic reaction area above, the biofilm biochemical reaction area is filled with biological fillers, the photocatalytic reaction area is filled with photocatalytic suspended fillers, the bottom of the biofilm biochemical reaction area is provided with a water inlet pipeline, and the water inlet pipeline passes through The water pump is connected to the raw water, and the top of the photocatalytic reaction zone is provided with a water outlet pipeline. The present invention integrates biofilm biochemical reaction and photocatalytic reaction in the same reaction device, horizontally separates through the middle perforated partition, realizes the switching of water flow direction through the middle vertical water corridor; through biochemical-photocatalytic, regeneration-photocatalytic After the catalytic two-stage treatment, the total degradation efficiency of the reaction device for organic matter can be improved; at the same time, the treatment process is shortened and the floor space is saved.

Description

Biofilm-photocatalytic integrated reaction device for pretreatment of slightly polluted raw water

technical field

The invention relates to a pretreatment device for slightly polluted raw water, which belongs to the technical field of environmental protection, in particular to a biofilm-photocatalytic integrated reaction device for pretreatment of slightly polluted raw water.

Background technique

Slightly polluted raw water refers to drinking water sources that are mainly polluted by organic matter, and some items exceed the standards stipulated in the "Environmental Quality Standards for Surface Water" (GB3838-2002) for Class III water bodies. The pollutants contained in this type of water are more diverse and complex in nature, but the concentration is relatively low.

Experimental research and actual production results at home and abroad have shown that conventional water purification processes are poor in removing organic matter, especially dissolved organic matter in slightly polluted raw water. requirements are more difficult. In addition, the concentration of ammonia nitrogen in many slightly polluted water sources in my country can often reach more than 3mg/L, far exceeding the 0.5mg/L ammonia nitrogen content in drinking water stipulated in the "Hygienic Standards for Drinking Water" (GB5749-2006) This is also a difficult problem that conventional treatment processes cannot effectively solve. In response to these problems of slightly polluted source water, the treatment technologies commonly used by various water plants include adding pretreatment, strengthening conventional processes and continuing advanced treatment.

Pretreatment usually refers to the primary removal of pollutants in water by using appropriate physical, chemical and biochemical treatment methods before conventional water purification processes, reducing the burden of conventional treatment, and improving and improving drinking water quality.

Biochemical treatment is a low-cost and mature water treatment technology, especially in the removal of ammonia nitrogen, which has an ideal effect. Photocatalytic oxidation has a good effect on the removal of refractory organic matter in water, and has energy Low consumption, simple operation, mild reaction conditions and so on. The combination of the two processes is applied to the pretreatment of slightly polluted raw water, and the synergistic effect of the two is brought into play. The strong oxidative active species such as hydroxyl radicals and superoxide radicals generated through the photocatalytic process can not only effectively solve the problem of slightly polluted raw water Ammonia nitrogen exceeds the standard, and it can realize the catalytic oxidation at normal temperature and pressure to efficiently remove natural organic matter (NOM) and synthetic organic matter (SOC) in water, so that organic matter can obtain inorganic mineralization, or improve the biodegradability of organic matter, and reduce the load of subsequent treatment and disinfection The production of by-products ensures the safety of drinking water.

Researchers have used photocatalytic-biological tandem combined treatment process to remove different types of pollutants in water, such as: H-acid, nitrocellulose, pesticides, EDTA and phenol. Photocatalytic oxidation can be used as the first step in the degradation process to decompose macromolecular substances into small molecular substances, destroy the molecular structure of organic substances, and improve the biodegradability of pollutants. Some researchers also use bio-oxidation-photocatalysis integrated technology to degrade phenol, nitrophenol and other pollutants. Biooxidation is the first step of degradation reaction, followed by photocatalytic reaction. After the pollutants are biooxidatively degraded, further oxidative degradation is carried out in the photocatalytic reactor until mineralization. However, the above-mentioned photocatalytic-biological oxidation tandem combination process has disadvantages such as long process flow, large floor area, and low catalytic efficiency.

Contents of the invention

The technical problem to be solved by the present invention is: in order to solve the deficiencies of the prior art, the present invention provides a biofilm-photocatalytic integrated reaction device for pretreatment of slightly polluted raw water, which has a simple structure, a small footprint and a short process flow , has a good effect on the degradation of pollutants, and is an easy-to-operate micro-polluted raw water treatment device.

The technical solution adopted by the present invention to solve the technical problem is: a biofilm-photocatalytic integrated reaction device for pretreatment of slightly polluted raw water, which has a device main body, a water inlet pipeline and an outlet pipeline connected to the device main body, and the The main body of the device is divided into a biofilm biochemical reaction area below and a photocatalytic reaction area above by a horizontal perforated partition. The biofilm biochemical reaction area is filled with biological fillers, and the photocatalytic reaction area is filled with photocatalytic suspended fillers. A water inlet pipeline is arranged at the bottom of the reaction zone, and the water inlet pipeline is connected to raw water through a water pump, and a water outlet pipeline is arranged at the top of the photocatalytic reaction zone.

In order to improve the purification effect, the main body of the device has a series-connected primary reaction area and a secondary reaction area, and the primary reaction area and the secondary reaction area are separated by a horizontal perforated partition into a biofilm biochemical The reaction zone and the photocatalytic reaction zone above, the water inlet pipeline is set at the bottom of the primary reaction zone, the top water outlet of the primary reaction zone is connected with the bottom water inlet of the secondary reaction zone, and the water inlet pipeline is connected to the raw water through a water pump, and the secondary reaction zone is connected to the raw water. A water outlet pipeline is arranged on the top of the reaction zone. It has two-stage purification, biochemical-photocatalytic, regeneration-photocatalytic, which can effectively improve the total degradation efficiency of pollutants in raw water, reduce the load of subsequent treatment and the generation of disinfection by-products, and ensure the safety of drinking water.

In order to better realize the switching of water flow, there is a vertical water passageway between the primary reaction zone and the secondary reaction zone for switching the flow direction of water flow. Raw water enters from the water inlet pipeline at the bottom of the primary reaction zone and passes through the biofilm biochemical reaction zone and the photocatalytic reaction zone in sequence, and then enters the secondary reaction zone after passing through the water corridor, and then passes through the biofilm biochemical reaction zone and the photocatalytic reaction zone in turn, and finally It is discharged from the outlet pipe at the top of the secondary reaction zone, and the water passage realizes the switching of the water flow between the primary reaction zone and the secondary reaction zone.

Preferably, the biological filler is polypropylene, and the photocatalytic suspension filler is an oblique-rotating porous composite filler mainly composed of polypropylene and nano-scale TiO ₂ . The filling ratio of the filler can be adjusted to adapt to the change of the raw water quality.

The density of the biological filler and the photocatalytic suspension filler is 900-1000kg/m ³ , and it is fluidized in water under a certain amount of aeration.

In order to provide sufficient oxygen, the main body of the device has an aeration pipe that ventilates into the biofilm biochemical reaction area and the photocatalytic reaction area. The aeration pipe is connected to an external blower through the air pipe, and the aeration pipe It is a perforated aeration tube or a membrane microporous aeration tube. The aeration tube makes the filler fluidized while increasing sufficient oxygen, improves the three-phase mass transfer efficiency of gas, liquid and solid, and improves the biochemical reaction efficiency of the biological filler and the photocatalytic efficiency of the photocatalytic suspended filler.

In order to improve the efficiency of the photocatalytic reaction zone, the top of the main body of the device is provided with an ultraviolet lamp tube that radiates ultraviolet rays to the photocatalytic reaction zone. Under the irradiation of ultraviolet lamps or sunlight, the TiO ₂ supported on the photocatalytic suspension filler is excited, and holes and free electrons are generated in the full band and conduction band respectively, and the holes generated by light have a strong ability to obtain electrons , can take away the organic matter on the surface of TiO ₂ particles or the electrons in the water, and finally generate OH free radicals with strong oxidizing ability, so that the organic matter that is difficult to degrade in the raw water is oxidized and decomposed.

Preferably, the wavelength of ultraviolet light emitted by the ultraviolet lamp tube is 254nm, and the power is adjustable in the range of 36-90W.

In order to facilitate the cleaning and maintenance of the device, the bottom of the main body of the device has a vent pipe for venting raw water and an on-off valve installed on the vent pipe to control opening and closing.

The beneficial effect of the present invention is that the biofilm-photocatalytic integrated reaction device for micro-polluted raw water pretreatment of the present invention integrates the biofilm biochemical reaction and photocatalytic reaction in the same reaction device, and performs lateral separation through the middle perforated partition, The switching of the water flow direction is realized through the vertical water passageway in the middle; after the two-stage treatment of biochemistry-photocatalysis and regeneration-photocatalysis, the total degradation efficiency of the reaction device for organic matter can be improved; at the same time, the treatment process is shortened, saving footprint.

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Fig. 1 is the structure schematic diagram of the first embodiment of the biofilm-photocatalytic integrated reaction device that the present invention is used for micro-polluted raw water pretreatment;

Fig. 2 is a schematic structural view of the second embodiment of the biofilm-photocatalytic integrated reaction device for pretreatment of slightly polluted raw water according to the present invention.

In the figure: 1. The main body of the device, 11. The primary reaction area, 12. The secondary reaction area, 13. The water inlet pipeline,

     14. Outlet pipeline, 2. Perforated partition, 3. Biofilm biochemical reaction area, 31. Biological filler,

4. Photocatalytic reaction zone, 41. Photocatalytic suspended filler, 5. Water corridor, 6. Aeration pipe,

7. Ultraviolet lamp.

Detailed ways

The present invention is described in further detail now in conjunction with accompanying drawing. These drawings are all simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, so they only show the configurations related to the present invention.

Fig. 1 is the first embodiment of the biofilm-photocatalytic integrated reaction device used for micropolluted raw water pretreatment of the present invention, has device main body 1, the water inlet pipeline 13 of communication device main body 1 and the water outlet pipeline 14, device The main body 1 is divided into a biofilm biochemical reaction zone 3 below and a photocatalytic reaction zone 4 above by a horizontal perforated partition 2. The biofilm biochemical reaction zone 3 is filled with biological fillers 31, and the photocatalytic reaction zone 4 is filled with photocatalytic suspension. Packing 41, the bottom of the biofilm biochemical reaction zone 3 is provided with a water inlet pipeline 13, and the water inlet pipeline 13 is connected to raw water through a water pump, and the top of the photocatalytic reaction zone 4 is provided with an outlet pipeline 14.

The biological filler 31 is polypropylene, and the biological filler 41 is extruded from polypropylene on a twin-screw extruder; the photocatalytic suspension filler 41 is an inclined-rotary porous composite filler mainly composed of polypropylene and nano-scale TiO ₂ , and the photocatalytic suspension filler 41 is co-extruded from polypropylene and nano-sized TiO ₂ on a twin-screw extruder. The density of biological filler 31 and photocatalytic suspension filler 41 is 900-1000kg/m ³ , and they are in a fluidized state under the action of aeration.

The main body of the device 1 has an aeration pipe 6 that ventilates into the biofilm biochemical reaction area 3 and the photocatalytic reaction area 4. The aeration pipe 6 is connected to an external blower through the air pipe. The aeration pipe 6 is a perforated aeration pipe or a diaphragm type Microporous aeration tube.

The top of the device main body 1 is provided with an ultraviolet lamp 7 that radiates ultraviolet light to the photocatalytic reaction zone 4. The ultraviolet light emitted by the ultraviolet lamp 7 has a wavelength of 254nm and an adjustable power in the range of 36-90W.

The bottom of the main body 1 of the device has a vent pipe for venting the raw water and a switch valve installed on the vent pipe to control opening and closing.

The first embodiment is a primary purification treatment device.

Fig. 2 is the second embodiment of the biofilm-photocatalytic integrated reaction device used for micro-polluted raw water pretreatment of the present invention, has device main body 1, the water inlet pipeline 13 of communication device main body 1 and the water outlet pipeline 14, device The main body 1 has a primary reaction zone 11 and a secondary reaction zone 12. The primary reaction zone 11 and the secondary reaction zone 12 are separated by a horizontal perforated partition 2 into a biofilm biochemical reaction zone 3 below and a photocatalytic reaction zone above. Reaction zone 4. Between the primary reaction zone 11 and the secondary reaction zone 12, there is a vertical water corridor 5 for switching the flow direction of the water flow. The bottom of the primary reaction zone 11 is provided with a water inlet pipeline 13, and the water inlet pipeline 13 is connected to the raw water through a water pump. The top of the secondary reaction zone 12 is provided with a water outlet pipeline 14 , and the top water outlet of the primary reaction zone 11 communicates with the bottom water inlet of the secondary reaction zone 12 through the water passage 5 . The arrows in the figure indicate the direction of water flow.

The biological filler 31 is polypropylene, and the biological filler 41 is extruded from polypropylene on a twin-screw extruder; the photocatalytic suspension filler 41 is an inclined-rotary porous composite filler mainly composed of polypropylene and nano-scale TiO ₂ , and the photocatalytic suspension filler 41 is co-extruded from polypropylene and nano-sized TiO ₂ on a twin-screw extruder. The density of biological filler 31 and photocatalytic suspension filler 41 is 900-1000kg/m ³ , and they are in a fluidized state under the action of aeration.

The main body of the device 1 has a perforated aeration pipe 6 ventilated into the biofilm biochemical reaction zone 3 and the photocatalytic reaction zone 4, and the perforated aeration tube 6 is connected to an external blower through an air duct.

The top of the device main body 1 is provided with an ultraviolet lamp 7 that radiates ultraviolet light to the photocatalytic reaction zone 4. The ultraviolet light emitted by the ultraviolet lamp 7 has a wavelength of 254nm and an adjustable power in the range of 36-90W.

The bottom of the main body 1 of the device has a vent pipe for venting the raw water and a switch valve installed on the vent pipe to control opening and closing.

The second embodiment is a two-stage purification treatment device, which is the optimal embodiment. A two-stage biofilm-photocatalytic integrated reaction device is used to pretreat slightly polluted raw water. When the raw water flow rate is 0.09m ³ /h, the average concentration of COD _Mn in the influent water is 8.50mg/L, and the average concentration of NH ₃ -N is 3.83mg/L , when the hydraulic retention time is 1h, the UV lamp power is 54W, and the filling ratio of photocatalytic suspended filler and biological filler is 40%, the average removal rates of COD _Mn and NH ₃ -N are 27.5% and 74.3%, respectively.

Claims (9)

1. one kind is used for the pretreated microbial film of micro-polluted raw-photochemical catalysis integrated reaction device; Has apparatus main body (1); The suction culvert (13) of communication apparatus main body (1) and outlet pipeline (14); It is characterized in that: described apparatus main body (1) is separated into the biomembrane biochemistry reaction zone (3) of below and the light-catalyzed reaction district (4) of top by horizontal perforation dividing plate (2); Fill photochemical catalysis floating stuffing (41) in the interior filled biomass filler of biomembrane biochemistry reaction zone (3) (31), light-catalyzed reaction district (4), the bottom of biomembrane biochemistry reaction zone (3) is provided with suction culvert (13); Suction culvert (13) is communicated with former water through water pump, and the top of light-catalyzed reaction district (4) sets out water lines (14).

2. the pretreated microbial film of the micro-polluted raw-photochemical catalysis integrated reaction device that is used for as claimed in claim 1; It is characterized in that: have placed in-line first order reaction district (11) and second order reaction district (12) in the described apparatus main body (1); Described first order reaction district (11) and second order reaction district (12) are separated into the biomembrane biochemistry reaction zone (3) of below and the light-catalyzed reaction district (4) of top by horizontal perforation dividing plate (2); The bottom in first order reaction district (11) is provided with suction culvert (13); The top water outlet in first order reaction district (11) is communicated with the bottom water-in of second order reaction district (12); Suction culvert (13) is communicated with former water through water pump, and the top of second order reaction district (12) sets out water lines (14).

3. the pretreated microbial film of the micro-polluted raw-photochemical catalysis integrated reaction device that is used for as claimed in claim 2 is characterized in that: have between described first order reaction district (11) and second order reaction district (12) and carry out the vertical water gallery (5) excessively that flow direction switches.

4. like claim 1 or the 2 or 3 described pretreated microbial film of the micro-polluted raw-photochemical catalysis integrated reaction devices that are used for, it is characterized in that: described biologic packing material (31) is a Vestolen PP 7052, and described photochemical catalysis floating stuffing (41) is mainly by Vestolen PP 7052 and nano level TiO ₂The oblique rotating porous compounded mix of forming.

5. the pretreated microbial film of the micro-polluted raw-photochemical catalysis integrated reaction device that is used for as claimed in claim 4, it is characterized in that: the density of described biologic packing material (31) and photochemical catalysis floating stuffing (41) is 900-1000kg/m ³

According to claim 1 or claim 2 be used for the pretreated microbial film of micro-polluted raw-photochemical catalysis integrated reaction device; It is characterized in that: the aeration tube (6) that has ventilation in biomembrane biochemistry reaction zone (3) and light-catalyzed reaction district (4) in the described apparatus main body (1); Described aeration tube (6) connects outside gas blower through airduct, and described aeration tube (6) is boring aeration pipe or microporous diaphragm aeration tube.

According to claim 1 or claim 2 be used for the pretreated microbial film of micro-polluted raw-photochemical catalysis integrated reaction device, it is characterized in that: described apparatus main body (1) top is provided with to the ultraviolet ultraviolet lamp tube of light-catalyzed reaction district (4) radiation (7).

8. the pretreated microbial film of the micro-polluted raw-photochemical catalysis integrated reaction device that is used for as claimed in claim 1, it is characterized in that: the ultraviolet wavelength that described ultraviolet lamp tube (7) sends is that 254nm, power are adjustable in 36～90W scope.

According to claim 1 or claim 2 be used for the pretreated microbial film of micro-polluted raw-photochemical catalysis integrated reaction device, it is characterized in that: described apparatus main body (1) bottom has the blow-down pipe that is used for the former water of emptying and is installed in the switch-valve that control opens and closes on the blow-down pipe.

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