CN204874184U - Photocatalysis membrane distillation printing and dyeing wastewater handles recycling system - Google Patents

Abstract

The utility model discloses a photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system, which comprises a water inlet pool, a photocatalytic degradation reaction pool, a membrane distillation biological reaction pool, a clear water pool connected in sequence, and the photocatalytic degradation reaction pool and the membrane distillation bioreaction The pool forms a circulation system through the second sewage pump and the second circulation pump; the clear water pool and the membrane distillation biological reaction pool are connected to form a circulation structure through two connecting pipes, and the first circulating pump and the condenser are respectively installed on the two connecting pipes; A water distribution plate is provided at the bottom of the catalytic degradation reaction tank, an aeration area is provided under the water distribution board, and a microwave electrodeless ultraviolet lamp is provided at the top of the photocatalytic degradation reaction tank. The utility model has a COD removal rate of more than 99% in waste water, a decolorization rate and a desalination rate of more than 99%, realizes high water purification, and a water recycling rate of more than 80%.

Description

Photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system

technical field

The utility model belongs to the field of printing and dyeing wastewater treatment, in particular to a photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system.

Background technique

The sustainable development of water resources and the development of water reuse projects have greatly promoted the development of water reuse technology, especially the reuse of printing and dyeing wastewater, and the water quality and reuse indicators are not the same. For the reuse of printing and dyeing wastewater, it mainly removes suspended particulate matter (SS), organic matter (COD/BOD), nitrogen and phosphorus compounds (N/P), inorganic ions and metal ions, salt and virus bacteria, etc.

Biological aerated filter (BAF) is a process developed in the late 1980s and widely used in water reuse systems. The biological aerated filter mainly conducts advanced treatment of organic carbon pollutants, ammonia nitrogen, phosphorus, etc. in wastewater. With the development of filter packing materials and the combination of aerobic and aerobic processes, BAF has been developed to remove SS, COD, and It also has strong functions of nitrification and denitrification, nitrogen and phosphorus removal, and removal of harmful substances (AOX).

Membrane technology due to its unique selective separation ability, with the maturity of technology in recent years and the decline of membrane manufacturing cost, membrane technology represented by membrane bioreactor (MBR) and double membrane method (UF+R0) has emerged Water reuse technology has unique advantages, especially in the fields of refractory organic matter, high salt content, chromaticity and other wastewater. However, low water yield, poor retention performance, and high energy consumption are still important factors restricting the wide application of reverse osmosis membranes.

Membrane distillation technology is a combination of membrane separation technology and distillation process. It has large evaporation area, high purity of produced water, and simple equipment. It is often used to treat high-concentration aqueous solutions; membrane separation is also combined with photocatalytic technology to form photocatalytic Membrane separation technology, membrane separation and traditional biochemical treatment form the most popular membrane bioreactor (MBR) technology at present. However, how to improve the effect of synchronous denitrification and phosphorus removal, how to effectively create a reasonable aerobic zone, anoxic zone, and anaerobic zone environment in the BAF system if the backwash system is properly set up still needs to be further explored.

Contents of the invention

In order to solve the above-mentioned technical problems, the utility model provides a photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system. The COD removal rate of the system in the wastewater water reaches more than 99%, and the decolorization rate and desalination rate reach more than 99%. Purification and reuse of water are ensured, and the recycling rate of water reaches more than 80%, which effectively saves water resources, and at the same time utilizes clean energy and reduces energy consumption.

The utility model is achieved through the following technical solutions:

Photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system, including sequentially connected water inlet tank, photocatalytic degradation reaction tank, membrane distillation biological reaction tank, clear water tank, between the upper part of the photocatalytic degradation reaction tank and the bottom of the membrane distillation biological reaction tank The connecting pipeline is provided with a second sewage pump, the connecting pipeline between the bottom of the photocatalytic degradation reaction tank and the bottom of the membrane distillation biological reaction tank is provided with a second circulating pump, and the photocatalytic degradation reaction tank and the membrane distillation biological reaction tank The circulation system is formed by the second sewage pump and the second circulation pump; the clear water tank and the membrane distillation biological reaction tank are connected to form a circulation structure through two connecting pipes, and the first circulation pump and the condenser are respectively installed on the two connecting pipes; the photocatalytic A water distribution plate is arranged at the bottom of the degradation reaction tank, an aeration area is arranged under the water distribution plate, and a microwave electrodeless ultraviolet lamp is arranged on the top of the photocatalytic degradation reaction tank.

The utility model scientifically combines the TiO ₂ microwave stepless ultraviolet photocatalysis technology and the membrane distillation technology, and through the synergistic effect of photocatalytic oxidation, adsorption catalytic oxidation, microwave desorption and accelerated oxidation, the organic matter in the waste water is rapidly degraded into CO ₂ , H ₂ O and other non-toxic and harmless small molecules, while using distillation membrane technology to desalinate the degraded solution, the removal rate of COD in wastewater water has reached more than 99%, and the decolorization rate and desalination rate have reached more than 99%, realizing the desalination of water Highly purified, the recycling rate of water reaches more than 80%. In addition, the sewage treated with multiple cycles can reduce membrane fouling in the next reaction process.

Preferably, the microwave electrodeless ultraviolet lamp is arranged in a quartz lampshade, and the outer wall of the quartz lampshade is evenly coated with powdered _TiO2 .

As a preference, an ozone decomposition device is also provided on the upper part of the photocatalytic degradation pool.

Preferably, the heat collector in the membrane distillation bioreactor is connected to the solar energy absorbing device. Realize the reuse of clean energy, greatly reduce energy consumption and save costs.

Preferably, both the first microporous aeration head and the second microporous aeration head at the bottom of the photocatalytic degradation reaction tank and the membrane distillation biological reaction tank are connected to a fan.

Preferably, a temperature sensor, a pH sensor and a liquid level controller are provided in the photocatalytic degradation reaction tank, and a temperature sensor and a pH sensor are provided in the membrane distillation biological reaction tank.

Preferably, the membrane pore diameter of the distillation membrane module is 0.1-0.4 μm.

The process of photocatalytic membrane distillation printing and dyeing wastewater treatment and recycling system includes the following steps:

Under the action of the first sewage pump, the printing and dyeing wastewater entering the water tank is input into the photocatalytic degradation reaction tank through the pipeline;

In the aeration area of the photocatalytic degradation reaction tank, the sewage is aerated under the action of the fan, and the aerated sewage is subjected to a microwave electrodeless ultraviolet photocatalytic reaction using a microwave electrodeless ultraviolet lamp;

The sewage after the microwave stepless ultraviolet photocatalytic reaction is pumped from the upper part of the photocatalytic degradation reaction tank by the second sewage pump into the aeration zone at the bottom of the membrane distillation biological reaction tank for aeration, and the aerated sewage is desalted through the distillation membrane module;

The aerated and desalted sewage circulates between the clear water tank and the membrane distillation biological reaction tank under the action of the first circulation pump, and is cooled under the action of the condenser, and the qualified clear water finally flows out through the clear water tank.

Preferably, the pH value in the photocatalytic degradation reaction tank is 6.5-7.5.

Preferably, the temperature in the clear water pool is 15-20°C.

Preferably, the temperature in the distillation membrane bioreactor is 50-60°C. It is especially suitable for high heat source sewage such as printing and dyeing wastewater.

The utility model has the following beneficial effects: the use of _TiO2 microwave stepless ultraviolet photocatalysis technology realizes the synergistic effect of photocatalytic oxidation, adsorption catalytic oxidation, microwave desorption and accelerated oxidation, improves the oxidation rate and effect, and at the same time, the light is strong and the service life is long. Long, reducing investment and operating costs; using membrane distillation technology, the equipment is simple, the water purity is high, at the same time, it avoids the high energy consumption of the double membrane method (UF+R0) combination device, and realizes energy saving and consumption reduction. The reaction pool of the utility model has the advantages of small occupied area, simple process, convenient maintenance, cost saving with high efficiency, and easy automatic control.

Description of drawings

Fig. 1 is a schematic diagram of the work flow of the utility model.

The meanings of the numbers in the figure are as follows: 1. Water inlet pool; 2. The first sewage pump; 3. Photocatalytic degradation reaction tank; 4. The first microporous aeration head; 5. Water distribution plate; 6. Quartz lampshade; 7 1. Microwave electrodeless ultraviolet lamp; 8. Ozone decomposition device; 9. Second sewage pump; 10. Membrane distillation biological reaction tank; 11. Heat collector; 12. Second microporous aeration head; 13. Distillation membrane module; 14. Condenser; 15. First circulating pump; 16. Liquid flow meter; 17. Clean water pool; 18. Solar absorbing device; 19. Second gas flow meter; 20. Second circulating pump; 21. Fan; 22. The first gas flow meter.

Detailed ways

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further elaborated below in conjunction with the accompanying drawings.

Example 1

As shown in Figure 1, a photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system includes an ozonolysis device 8, a solar energy absorption device 18, and a water inlet pool 1, a photocatalytic degradation reaction pool 3, and a membrane distillation biological reaction pool 10 connected in sequence , clean water pool 17, the bottom of water inlet pool 1 and photocatalytic degradation reaction tank 3 is connected by first sewage pump 2, and the top of photocatalytic degradation reaction tank 3 and the bottom connection pipeline of membrane distillation biological reaction tank 10 are provided with second sewage pump 9. The bottom of the photocatalytic degradation reaction tank 3 and the bottom connecting pipeline of the membrane distillation bioreactor 10 are provided with a second circulation pump 20, and the photocatalytic degradation reaction tank 3 and the membrane distillation bioreactor 10 pass through the second sewage pump 9, The second circulation pump 20 constitutes a circulation system, and the top of the membrane distillation bioreactor 10 is connected in circulation through the first circulation pump 15, the condenser 14 and the clear water tank 17, and the temperature of the circulation cooling zone is controlled at 15-20°C.

The ozone decomposing device 8 is connected to the upper part of the photocatalytic degradation pool 3 to realize the collection and decomposition of ozone.

The solar absorbing device 18 is connected with the heat collector 11 inside the membrane distillation bioreactor 10 . This embodiment adopts the heat collection principle of temperature difference control. When the solar heat source absorbing device 18 absorbs solar radiation, the temperature of the heat collecting tube rises and reaches the set value of the water temperature difference Δt between the heat collector 11 and the distillation membrane bioreactor 10, and the detection system Send an instruction, the cold water in the central water heater is input in the heat collector 11, and the water returns to the distillation membrane bioreaction tank 10 after being heated, so that the water in the distillation membrane bioreaction tank 10 reaches the set temperature. The temperature of the heating zone is controlled to be 50-60°C.

T, pH and LT in the figure are temperature sensor, pH sensor and liquid level controller respectively, monitoring and controlling the environmental changes in the photocatalytic degradation reaction tank 3 and the membrane distillation biological reaction tank 10 . The pH value in the photocatalytic degradation reaction tank 3 is 6.5-7.5.

The photocatalytic degradation reaction pool 3 is divided into two areas by the water distribution plate 5, the upper part of the water distribution plate is the TiO ₂ photocatalytic reaction area, and the lower part is the aeration area, and the aeration area is equipped with the first microporous aeration head 4; the TiO ₂ The photocatalytic reaction zone is equipped with a microwave electrodeless ultraviolet lamp 7 and a quartz lampshade 6, and the microwave electrodeless ultraviolet lamp 7 is arranged in a colorless and transparent hollow quartz lampshade 6, and the outside of the quartz lampshade 6 is uniformly coated with a powdery semiconductor catalyst TiO ₂ film; The filling material in the microwave electrodeless ultraviolet lamp 7 is mainly metallic mercury and some inert gases, among which, mercury vapor is the working gas in the lamp, and the inert gas is the starting gas; the frequency of microwave discharge is 2450-5000MHz; the microwave electrodeless ultraviolet lamp 7Use a microwave-excited electrodeless ultraviolet light source to realize the three-in-one combination of microwave, ultraviolet and ozone generation, and cooperate with the recyclable high-efficiency catalyst TiO ₂ to realize the synergistic effect of photocatalytic oxidation, adsorption catalytic oxidation, microwave desorption and accelerated oxidation. The organic matter rapidly degrades into CO ₂ , H ₂ O and other non-toxic and harmless small molecules.

The membrane distillation bioreactor 10 is provided with a distillation membrane assembly 13 and a second microporous aeration head 12 , and a second microporous aeration head 12 and a heat collector 11 are installed below the distillation membrane assembly 13 . The distillation membrane module 13 adopts polytetrafluoroethylene PTFE membrane or polypropylene PP membrane, and the membrane pore diameter is 0.1-0.4 μm. In this embodiment, a hydrophobic distillation membrane is used. The solution on both sides of the distillation membrane cannot pass through the hydrophobic membrane, but water vapor can be freely transported through the dry micropores in the membrane. Due to the effect of the heat collector 11, there is a relatively high temperature difference between the solutions on both sides of the distillation membrane, and the water vapor pressure at the interface between the warm side solution and the membrane is higher than that of the cold side, and the water vapor will enter the cold side from the warm side through the membrane pores and condense , which provides favorable conditions for the realization of the membrane distillation process.

The first microporous aeration head 4 is connected to the external fan 21 through the first gas flow meter 22 , and the second microporous aeration head 12 is connected to the fan 21 through the second gas flow meter 19 .

Working process: the sewage in the water inlet tank 1 is pumped into the aeration area at the bottom of the photocatalytic degradation reaction tank 3 by the first sewage pump 2, and the fan 21 and the first microporous aeration head 4 are used to aerate the sewage, and the aerated sewage is distributed by the water The plate 5 enters the photocatalytic reaction zone, and the microwave electrodeless ultraviolet light 7 and the quartz lampshade 6 are used to carry out the microwave electrodeless ultraviolet photocatalytic reaction, and the organic matter in the waste water is rapidly degraded into CO ₂ by the strong oxidation of holes induced by TiO ₂ , H ₂ O and other non-toxic and harmless small molecules, and realize photocatalytic oxidation, adsorption catalytic oxidation, and microwave desorption at the same time; the sewage after oxidation and adsorption is pumped into the membrane distillation biological reaction tank 10 by the second sewage pump 9, and the membrane distillation The bottom of the biological reaction tank 10 is aerated by the fan 21 and the second microporous aeration head 12. The aerated sewage is desalted through the distillation membrane module 13, circulated and cooled by the first circulation pump 15 and the condenser 14, and finally passed through the clear water tank 17. flow out. The second circulating pump 20 can pump the sewage aerated in the membrane distillation biological reaction tank 10 to the bottom of the photocatalytic degradation reaction tank 3 for re-aeration to reduce membrane fouling.

Example 2

The above devices and processes are used to treat the production wastewater of a printing and dyeing enterprise in Jiangsu.

The concentration of COD (chemical oxygen demand) in the photocatalytic degradation reaction pool is 820mg/L, and the concentration of BOD ₅ (the amount of free oxygen consumed by aerobic microorganisms to oxidize and decompose organic matter per unit volume of water on the fifth day) is 270mg/L. The average chromaticity of the water is 370 times, the inlet water temperature is 16-18°C, the pH is 7.0-8.0, and the conductivity is 2580μs/cm.

During the test operation, the pH of the photocatalytic degradation reaction tank is 6.5-7.0, the hydraulic retention time HRT is 6h, the water temperature T at the bottom of the distillation membrane biological reaction tank is 52-54°C, the pH is 6.5-7.0, and the water temperature of the cooling circulation system is 16-18 ℃, the membrane material is hydrophobic vinyl fluoride PVDF membrane, and the membrane flux is 14-18L/m ² h.

The result of the test effluent is: the COD concentration is 7.5mg/L, BOD ₅ , TN and TP are not detected, the average chromaticity is 1.2 times, basically colorless, and the conductivity is 25μs/cm. The results show that the COD in the wastewater The removal rate reached 99.1%, and the decolorization rate and desalination rate reached more than 99%, realizing a high degree of water purification.

What is disclosed above is only a specific embodiment of the present application, but the present application is not limited thereto, and any changes conceivable by those skilled in the art shall fall within the protection scope of the present application.

Claims (7)

1. The photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system is characterized in that it includes a water inlet pool (1), a photocatalytic degradation reaction pool (3), a membrane distillation biological reaction pool (10), and a clear water pool (17) connected in sequence , the connecting pipeline between the upper part of the photocatalytic degradation reaction tank (3) and the bottom of the membrane distillation biological reaction tank (10) is provided with a second sewage pump (9), the bottom of the photocatalytic degradation reaction tank (3) and the membrane A second circulation pump (20) is provided on the connecting pipeline between the bottom of the distillation bioreactor (10), and the photocatalytic degradation reaction tank (3) and the membrane distillation bioreaction tank (10) pass through the second sewage pump (9) 1. The second circulation pump (20) constitutes a circulation system; the clear water tank (17) and the membrane distillation bioreactor (10) are connected to form a circulation structure through two connecting pipes, and the first circulating pump (15 ) and a condenser (14); the bottom of the photocatalytic degradation reaction tank (3) is provided with a water distribution plate (5), and an aeration area is provided under the water distribution plate (5), and the top of the photocatalytic degradation reaction tank (3) A microwave electrodeless ultraviolet lamp (7) is provided. 2. The photocatalytic membrane distillation printing and dyeing wastewater treatment and recycling system according to claim 1, characterized in that the microwave electrodeless ultraviolet lamp (7) is set inside the quartz lampshade (6), and the outer wall of the quartz lampshade (6) is evenly coated with Powdered TiO ₂ . 3. The photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system according to claim 1, characterized in that an ozone decomposition device (8) is also installed on the upper part of the photocatalytic degradation reaction pool (3). 4. The photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system according to claim 1, characterized in that the heat collector (11) in the membrane distillation biological reaction tank (10) is connected to the solar energy absorbing device (18). 5. The photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system according to claim 1, characterized in that the first microporous aeration head at the bottom of the photocatalytic degradation reaction tank (3) and the membrane distillation biological reaction tank (10) (4), the second microporous aeration head (12) is connected with the blower fan (21). 6. The photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system according to claim 1, characterized in that the photocatalytic degradation reaction tank (3) is equipped with a temperature sensor, a pH sensor and a liquid level controller, and the membrane distillation biological reaction A temperature sensor and a pH sensor are arranged in the pool (10). 7. The photocatalytic membrane distillation printing and dyeing wastewater treatment and reuse system according to claim 1, characterized in that the membrane pore diameter of the distillation membrane module (13) is 0.1-0.4 μm.