CN201433151Y - A device for treating slightly polluted surface water - Google Patents

Abstract

A device for treating slightly polluted surface water belongs to the technical field of deep purification treatment of drinking water. The device includes a raw water tank, a raw water filter, a biological filter, a coagulation tank, a sedimentation tank, an intermediate tank, an ultrafiltration membrane module and a clear water tank. There is a raw water pump between the raw water tank and the biological filter; the biological filter and the coagulation tank are connected by pipes and valves; the coagulation tank, the sedimentation tank and the intermediate tank are respectively connected by pipelines and valves; There is an ultrafiltration inlet pump between them; the ultrafiltration membrane module is connected to the clear water tank through pipes and valves; a blast aeration system and a biofilter backwash system are installed at the bottom of the biofilter; Medicine system, ultrafiltration backwash system is installed outside the ultrafiltration membrane module. The utility model organically combines biodegradation and coagulation with the physical interception of ultrafiltration, and has a good removal effect on ammonia nitrogen and organic matter in slightly polluted surface water, and is a new type of deep purification equipment for drinking water.

Description

A device for treating slightly polluted surface water

technical field

The utility model relates to a water treatment device, in particular to a device for treating slightly polluted surface water by combining a biological filter tank-coagulation sedimentation-ultrafiltration membrane, and belongs to the technical field of deep purification treatment of drinking water.

Background technique

In the face of changes in water quality, conventional drinking water treatment processes have become inadequate. Experimental research and actual production results at home and abroad show that conventional coagulation, sedimentation and filtration processes can only remove 20% to 30% of the organic matter in the polluted source water, and the presence of dissolved organic matter is not conducive to destroying the stability of the colloid The removal effect of the conventional process on raw water turbidity is significantly reduced (only 50% to 60%). To improve the treatment effect by increasing the dosage of coagulant will not only increase the cost of water treatment, but also may increase the concentration of metal ions in the water, which is not conducive to the health of residents. Conventional treatment of excessive ammonia nitrogen, which is ubiquitous in surface water sources, cannot be effectively resolved. At present, most water plants in China use the method of breakpoint chlorination to control the concentration of ammonia nitrogen in the discharged water to obtain the necessary active residual chlorine, but the resulting large amount of organic halides leads to a decline in the toxicological safety of water quality.

At the same time, new pathogenic protozoa-Giardia lamblia and Cryptosporidium (“two insects”) were discovered in water at the end of the 20th century, and algal blooms, algae toxins, smell, water biological stability, and harmful aquatic organisms appeared -Major microbial safety issues such as water fleas and red worms cannot be effectively solved by the existing conventional coagulation sedimentation filtration disinfection technology. Under this background, a safer and more effective urban drinking water purification process needs to be developed.

As a new technology of micro-polluted water treatment with membrane technology as the core, it has attracted widespread attention and is known as one of the most promising water treatment technologies in the 21st century. The ultrafiltration membrane can effectively intercept particulate matter in the water, reduce the turbidity of the effluent to below 0.1NTU, and remove macromolecular organic matter, as well as most microorganisms such as algae, daphnia, red worms, two worms, bacteria and even viruses.

Patents involving ultrafiltration treatment of slightly polluted water as drinking water, such as "Ultrafiltration Membrane Coagulation/Adsorption/Bioreactor Integrated Water Advanced Treatment Method and Device" 200810063897.7, adopt an integrated device situation and save floor space At the same time, there is the problem of low operating flux; the patent "ultrafiltration-jet supplementary ozone-ultraviolet secondary excitation to generate free radicals to purify micro-polluted water source water technology and process" 02128903.4, while ultraviolet disinfection and secondary excitation of water Dissolved oxygen and ozone generate strong oxidizing free radicals, which can kill various pathogens and remove suspended solids, etc., but cannot remove ammonia nitrogen in micro-polluted surface water; "Combined Ultrafiltration Membrane Treatment Device for Drinking Water Treatment" The 200420109820.6 utility model is the optimization of the combination of disinfection method and ultrafiltration, which does not involve biological pretreatment, nor can it remove ammonia nitrogen in slightly polluted surface water.

In the face of the gradual deterioration of water sources and the gradual improvement of drinking water standards, how to apply ultrafiltration membrane technology to drinking water treatment projects to ensure the high quality, safety, stability and stability of the treated water is currently a super Problems to be solved urgently in membrane drinking water treatment process.

Utility model content

The purpose of the utility model is to develop an advanced treatment equipment for drinking water that can significantly improve the quality of effluent water for slightly polluted surface water sources.

A device for treating slightly polluted surface water provided by the utility model is characterized in that: the device includes a raw water pool 1, a raw water filter 2, a biological filter tank 3, a coagulation tank 4, a sedimentation tank 5, an intermediate pool 15, Ultrafiltration membrane module 6 and clear water tank 16; Raw water pump 7 is provided between described raw water tank and biofilter; Between biofilter and coagulation tank, connect with valve through pipeline; Coagulation tank, sedimentation tank and The intermediate pools are connected through pipes and valves; an ultrafiltration water inlet pump 11 is provided between the intermediate pool and the ultra-membrane module; gas system and biofilter backwash system; a dosing system 8 is provided outside the coagulation tank, and a stirring device 14 is provided in the coagulation tank; an ultrafiltration backwash system is provided outside the ultrafiltration membrane module .

The sedimentation tank in the above device adopts an inclined tube sedimentation tank or an inclined plate sedimentation tank; the ultrafiltration membrane module is an external type, and the membrane material is polyvinylidene fluoride or polyvinyl chloride, and the membrane pore diameter is 0.01 to 0.1 microns; The feed material of the biological filter adopts zeolite or ceramsite.

The utility model has the following advantages: Aiming at the pollution of drinking water sources by organic matter and ammonia nitrogen, biological treatment is combined with conventional coagulation sedimentation and ultrafiltration organically, ammonia nitrogen and some small molecular organic matter are removed through biological treatment, coagulation sedimentation Part of the medium and macromolecular organic matter is removed, and finally through the high-efficiency interception effect of the ultrafiltration membrane, the particulate matter and microorganisms are removed, so that the effluent can meet the standard of high-quality drinking water. The utility model adopts an external ultrafiltration membrane assembly, which effectively improves the membrane flux, reduces the use area of the ultrafiltration membrane, facilitates the replacement of the assembly, and reduces the engineering cost and operation cost. At the same time, the external membrane module is used to further reduce the leakage of microorganisms and particles. The concentrated liquid in the ultrafiltration membrane module of the utility model is returned to the coagulation sedimentation tank, and the solid-liquid separation is carried out in the coagulation sedimentation tank, thereby further improving the utilization rate of water.

Description of drawings

Figure 1 is a structure and process flow chart of a device for treating slightly polluted surface water provided by the utility.

In the figure: 1-raw water pool; 2-raw water filter; 3-biological filter; 4-coagulation tank; 5-sedimentation tank; 6-ultrafiltration membrane module; 7-raw water pump; 8-dosing system; 9 -fan; 10-biological filter backwash pump; 11-ultrafiltration inlet pump; 12-backwash air compressor; 13-ultrafiltration backwash pump; 14-stirring device; 15-intermediate pool; 16-clear water pool.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described.

Fig. 1 is a kind of structural flow chart of the device for processing slightly polluted surface water provided by the utility model, and the device comprises a raw water tank 1, a raw water filter 2, a biological filter tank 3, a coagulation tank 4, a sedimentation tank 5, an intermediate Pool 15, ultrafiltration membrane assembly 6 and clear water pool 16; Raw water pump 7 is provided between described raw water tank and biofilter; Between biofilter and coagulation tank, be connected with valve by pipeline; Coagulation tank, The sedimentation tank and the intermediate tank are respectively connected by pipelines and valves; an ultrafiltration water inlet pump 11 is provided between the intermediate tank and the ultra-membrane module; the ultrafiltration membrane module is connected to the clean water tank 16 through pipelines and valves; Blast aeration system and biological filter backwash system; a dosing system 8 is provided outside the coagulation tank, and a stirring device 14 is provided inside the coagulation tank; Filter backwash system. The biological filter uses zeolite or ceramsite as the additive. The sedimentation tank adopts inclined tube sedimentation tank or inclined plate sedimentation tank.

The specific process flow is as follows: raw water to be treated, including lakes and reservoirs with low turbidity, and river water after preliminary clarification treatment, etc. in the raw water pool 1, from the raw water pump 7 to the biological filter 3 through the filter 2; The hydraulic retention time of the filter is in the range of 10 to 60 minutes, and ammonia nitrogen and organic matter are degraded in the biological filter 3 . The biological filter is an aerated biological filter, and the material of the biological filter is zeolite or ceramsite; the air is supplied to the biological filter 3 by the fan 9, and the air-water ratio is in the range of 0.5:1 to 2:1 to meet the needs of microorganisms. Oxygen. And backwash the biofilter regularly, pump water from the clear water pool 16 through the biofilter backwash pump 10 and pump water into the biofilter 3 from the bottom, and the compressed air provided by the backwash air compressor 12 enters from the bottom of the biofilter , to backwash the biofilter; the backwash effluent controls the discharge system through a solenoid valve, and the solenoid valve is synchronized with the backwash pump 10; at the same time, a sludge discharge device is installed at the bottom of the biofilter to regularly discharge sludge to the biofilter. The effluent from the biological filter 3 reaches the coagulation tank 4, and the coagulant is added to the coagulation tank by the dosing system 8. The coagulant can be polyaluminum chloride, ferric chloride, aluminum sulfate, polyaluminum ferric sulfate or other One or several coagulants that can be used for drinking water production. In the coagulation tank 4, the mixed solution is stirred evenly by the stirring device 14 and then flows into the inclined plate (or inclined tube) sedimentation tank 5 by itself. After coagulation and precipitation, the organic matter of medium molecules and large molecules can be removed. Solid-liquid separation is carried out, the sludge in the sedimentation tank is regularly discharged from the system through the pipeline and controlled by the valve, and the supernatant flows into the intermediate pool 15 by itself; the ultrafiltration inlet pump 11 is sucked and pressurized from the intermediate pool 15 to the ultrafiltration membrane module In 6, the material of the ultrafiltration membrane can be polyvinylidene fluoride or polyvinyl chloride or other ultrafiltration membranes, the pore size should be in the range of 0.01 micron to 0.1 micron, and the form of the ultrafiltration membrane module can be hollow fiber or roller shutter. The ultrafiltration membrane pressure is controlled by the ultrafiltration membrane module 11 in the range of 0.01MPa to 0.15MPa, the membrane flux is in the range of 20L/m ² .h to 100L/m ² .h, and the ultrafiltration concentrate is returned to the coagulation tank so that Cross-flow is formed in the ultrafiltration membrane module, and the solid-liquid separation is carried out through the sedimentation tank or the solid-liquid separation is carried out after the effluent is coagulated and precipitated when the ultrafiltration membrane is backwashed. In order to ensure the membrane flux, the ultrafiltration membrane module is regularly backwashed. Periodically, the ultrafiltration backwash pump 13 pumps water from the clean water tank into the ultrafiltration membrane module 6, and at the same time, the backwash air compressor 12 provides backwashing air for the ultrafiltration membrane module to form gas in the ultrafiltration membrane module 6. Water backwashes. When backwashing, close the ultrafiltration water inlet, ultrafiltration outlet water and return valve, and open the backwash inlet, backwash outlet water and backwash inlet valve. The backwash cycle is determined according to the ultrafiltration membrane pressure and membrane flux. The ultrafiltration membrane effluent goes to the clear water pool 16, and can be transported to the user after being sterilized.

Give a specific example below

Example 1: The raw water to be treated is lake water. The raw water pump draws water from the raw water pool and enters the biofilter through the disc filter. The biofilter adopts 2-3mm zeolite. The hydraulic retention time in the biofilter is 30min, and the gas-water ratio is 2:1. The effluent enters the coagulation sedimentation tank, and the dosing system adds polyaluminum chloride to the coagulation sedimentation tank at a rate of 6 mg/L. After coagulating for 5 minutes, it enters the inclined plate sedimentation tank, settles in the inclined plate sedimentation tank for 30 minutes, and the supernatant After entering the middle pool, it is sucked and pressurized by the ultrafiltration pump into the ultrafiltration membrane module. The ultrafiltration membrane has a pore size of 0.03 microns and is made of polyvinylidene fluoride external ultrafiltration membrane module. The flux is 20L/m ² .h, and the pressure varies from 0.05 to 0.07Mpa. After filtering for 30 minutes and backwashing for 1 minute and 30 seconds, the effluent from the ultrafiltration membrane module enters the clean water pool, where it can be sterilized and delivered to users. The quality of influent and effluent water is shown in Table 1.

Table 1

Example 2:

The raw water to be treated is river water. The raw water pump draws water from the raw water pool and enters the biofilter through the disc filter. The biofilter uses 2-3mm zeolite. The hydraulic retention time in the biofilter is 10 minutes, and the gas-water ratio is 0.5:1. The effluent enters the coagulation sedimentation tank, and the dosing system adds polyaluminum chloride to the coagulation sedimentation tank at a rate of 4 mg/L. After coagulating for 5 minutes, it enters the inclined plate sedimentation tank, settles in the inclined plate sedimentation tank for 30 minutes, and the supernatant After entering the middle pool, it is sucked and pressurized by the ultrafiltration pump into the ultrafiltration membrane module. The ultrafiltration membrane has a pore size of 0.1 micron and is made of polyvinylidene fluoride external ultrafiltration membrane module. The flux is 100L/m ² .h, and the pressure varies between 0.12 and 0.15Mpa. After filtering for 30 minutes and backwashing for 1 minute and 30 seconds, the effluent from the ultrafiltration membrane module enters the clean water pool, where it can be sterilized and delivered to users. The quality of influent and effluent water is shown in Table 2.

Table 2

Claims (4)

1. device of handling micro-polluted surface water, it is characterized in that: described device comprises former pond (1), raw water filtration device (2), biological filter (3), coagulation basin (4), settling tank (5), intermediate pool (15), hyperfiltration membrane assembly (6) and clean water basin (16); Between described former pond and biological filter, be provided with raw water pump (7); Between biological filter and coagulation basin, be connected with valve by pipeline; Coagulation basin, settling tank and intermediate pool are connected by pipeline and valve respectively; Be provided with ultrafiltration intake pump (11) between intermediate pool and the supermembrane assembly; Hyperfiltration membrane assembly is connected with clean water basin (16) with valve by pipeline; Be provided with blast aeration system and biological filter back-purge system in the bottom of biological filter; Be provided with medicine system (8) in described coagulation basin outside, in coagulation basin, be provided with whipping appts (14); Described hyperfiltration membrane assembly outside is provided with the hyperfiltration reverse-rinsing system.

2. a kind of device of handling micro-polluted surface water according to claim 1 is characterized in that: described biological filter adopts zeolite or haydite for adding material.

3. a kind of device of handling micro-polluted surface water according to claim 1 and 2 is characterized in that: described settling tank adopts tube settler or inclined-plate clarifying basin.

4. according to right 1 described a kind of device of handling micro-polluted surface water, it is characterized in that: described hyperfiltration membrane assembly adopts external placed type, and mould material is polyvinylidene difluoride (PVDF) or polyvinyl chloride, and the fenestra aperture is at 0.01～0.1 micron.

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