CN116177798A - Natural running water ozone ultrafiltration membrane water purification treatment method - Google Patents

Abstract

The invention relates to a natural running water ozone ultrafiltration membrane water purification treatment method, which is characterized by comprising the following steps: s1, injecting self-flowing water containing algae into a coagulation box, adding a flocculating agent into the coagulation box, and reacting for a certain time to obtain mixed condensate; s2, enabling the coagulating liquid to enter a circulating slag removal box, wherein a partition plate is arranged in the circulating slag removal box, the coagulating liquid forms a vertical circulating flow in the circulating slag removal box, algae floats are discharged by a slag discharge pipe, and sediment is discharged from a bottom mud discharge pipe; mixing the clear liquid obtained after deslagging with ozone through a gas-liquid mixing pump to form a gas-water mixture; s3, filtering the air-water mixture by a self-cleaning filter, and then enabling the air-water mixture to enter an ultrafiltration membrane purifier; purified water filtered by the ultrafiltration membrane purifier flows out of a purified water pipe at the upper part of the ultrafiltration membrane purifier, and solution gas and solution formed in front of the ultrafiltration membrane flows back to the circulating slag removal box through a return pipe. The invention has the advantages of high algae removal efficiency, strong anti-fouling and blocking capacity, simple pretreatment operation and the like.

Description

A kind of natural flowing water ozone ultrafiltration membrane water purification treatment method

technical field

The invention relates to the technical field of water purification treatment, in particular to a natural flowing water ozone ultrafiltration membrane water purification treatment method.

Background technique

The Hygienic Standard for Drinking Water (GB5749-2022) was released in March 2022 and will be implemented on April 1, 2023. The standard deletes the provisional provisions on water quality indicators and limit values for small-scale centralized and decentralized water supply, which means that the water quality requirements for urban and rural water supply are homogeneous. Higher requirements are put forward for the water quality of small centralized and decentralized water supply. Small-scale centralized and decentralized water supply is mainly distributed in rural areas, pastoral areas, mining areas, and factories far away from urban municipal pipe networks. Natural conditions often have the characteristics of poor water quality, prone to algae outbreaks, and large seasonal changes, and lack professionalism in management. manager. It makes it difficult for the traditional coagulation, sedimentation, and sand filtration processes to meet the standards stably. The water purification treatment method of ultrafiltration membrane treatment has the advantages of low turbidity of purified water effluent and good water quality, which has attracted attention. However, the conventional full-flow ultrafiltration membrane water purification process requires high pretreatment of raw water, otherwise the membrane pores are easily blocked and affect normal use. Cross-flow filtration can solve the problem of membrane pore clogging, but its high energy consumption and high operating costs also make it difficult to promote its use. There is an urgent need for a water purification process with high algae removal efficiency, strong anti-fouling ability, and simple pretreatment operation. The self-cleaning filter is a precision device that uses the filter to directly intercept impurities, floating objects, particles, etc. in the liquid, while reducing the turbidity of the water, reducing dirt, and at the same time ensuring the normal operation and service life of the subsequent equipment. It has automatic The characteristics of sewage.

Contents of the invention

The technical problem to be solved by the present invention is to provide an ultrafiltration membrane water purification process with high algae removal efficiency, strong anti-fouling ability and simple pretreatment operation.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions, a natural flowing water ozone ultrafiltration membrane water purification treatment method, which is characterized in that the following steps are adopted:

S1. Inject algae-containing artesian water into the coagulation tank, add flocculant into the coagulation tank, and react for a certain period of time to obtain a coagulation solution;

S2. Put the coagulation liquid into the circulating slag removal box, the inside of the circulating slagging removal box is provided with a partition, the upper part of the circulating slagging removal box is provided with a slag discharge pipe, and the bottom is provided with a mud discharge pipe. The liquid forms a vertical circulation flow in the circulating slag removal box, the algae floating matter is discharged from the slagging discharge pipe, and the sediment is discharged from the bottom mud discharge pipe; The gas-liquid mixing pump is mixed with ozone to form a gas-water mixture;

S3, the gas-water mixture enters the ultrafiltration membrane purifier after being filtered by the self-cleaning filter; the purified water filtered by the ultrafiltration membrane purifier flows out from the water purification pipe on the upper part of the ultrafiltration membrane purifier, and forms in front of the ultrafiltration membrane The dissolved gas liquid is returned to the circulating slag removal box through the return pipe.

Furthermore, the upward floating force of algae and scum in the circulating scum removal box is generated by the release of dissolved gas from the gas-dissolving liquid entering the return pipe.

The self-cleaning filter is a conventional standard industrial product.

Further, the ultrafiltration membrane is a ceramic ultrafiltration membrane, a silicon carbide ultrafiltration membrane, a PTFE ultrafiltration membrane, or a PVDF ultrafiltration membrane.

As shown in Fig. 1, Fig. 2 and Fig. 3, the present invention first mixes algae-containing natural running water and flocculant evenly through a coagulation tank to form a coagulation liquid with granular alum flowers. The coagulation liquid enters the circulating slag removal box 2, and a partition plate 5 is set between the water inlet pipe 3 and the water outlet pipe 4 of the circulating slag removal box to block it, and the returning air-dissolved liquid enters the circulating slag removal box through the return pipe 6 located above the water inlet pipe 3 In the middle of 2, after the gas-dissolved liquid enters the circulating deslagging tank 2, due to the pressure drop, the gas originally dissolved in the gas-dissolved liquid is released to form tiny bubbles, and the bubbles float the gas-dissolved liquid and the lighter particles in the natural running water containing algae to the circulating deslagging On the upper part of the slag box 2, the scum is discharged through the slag discharge pipe 7 at the top of the circulating slag removal box 1. At the same time, due to the driving effect of the air bubbles, the coagulation liquid flows upwards and turns over the partition, and then flows downwards into the outlet pipe 4. Due to the action of the air bubbles, the water volume lifted is much greater than the water outlet volume, and the remaining water continues to flow downward and is discharged from the space at the bottom of the partition. Turn into the inlet side of the water inlet pipe 3, thus forming an up and down circulation in the circulating slag removal box 1, which is beneficial to the uniform stirring of the flocculant. Due to the effect of circulation, some of the heavier particles are brought to the bottom of the circulating slag removal box 2 and discharged through the mud discharge pipe 9 .

The clear liquid obtained after slag removal is uniformly mixed with ozone through the gas-liquid mixing pump 10, and part of the ozone dissolves into the flocculation liquid under pressure, and is evenly distributed in the flocculation liquid in the form of bubbles, and disperses to form a gas-water mixture. The gas-water mixture is first filtered through the self-cleaning filter 11 , then enters from the bottom of the ultrafiltration membrane purifier 12 , and then rises evenly and enters the ultrafiltration membrane purification channel 13 . The filtered clean water flows out from the clean water pipe 14 under pressure. The concentrated liquid and gas intercepted by the ultrafiltration membrane wash along the surface of the membrane, gather in the return pipe 6, and return to the circulating slag removal box 2.

The invention utilizes the strong oxidation ability of the ozone and the agitation effect of the air flow to slow down the problems of fouling and fouling on the surface of the ultrafiltration membrane.

The invention utilizes the dissolved ozone in the gas-dissolved liquid to kill algae on the one hand, and on the other hand utilizes pressure to reduce gas release to float out algae and lighter scum, thereby improving the algae removal effect of pretreatment before ultrafiltration.

The present invention pumps clear water and ozone into the ultrafiltration membrane purifier 12 through the gas-liquid mixing pump 11. On the one hand, the ozone and clear water are evenly mixed in the pipeline; Problems with no stress or not enough stress.

The invention utilizes the gas-liquid mixing pump to evenly mix the ozone, and at the same time breaks the large flocculation particles into fine particles, so as to avoid blocking the channel of the membrane purifier.

To sum up, the present invention has the beneficial effects of high algae removal efficiency, strong anti-fouling ability, simple pretreatment operation and the like.

Description of drawings

Fig. 1 is a schematic diagram of the process flow of the present invention.

Figure 2 is a schematic diagram of the structure of the circulating slag removal box.

Fig. 3 Schematic diagram of the ultrafiltration membrane purifier.

Implementation

In conjunction with accompanying drawing, a kind of ultrafiltration membrane water purification treatment method of natural flow containing algae raw water of the present invention is further described, and the present invention is described in further detail below in conjunction with embodiment:

Example 1: It is a rural water supply system in a plain area. The source of water intake is river water. The turbidity of raw water is 15-200NTU. Seasonal algal blooms occur. The daily water supply is 100m3/d, and the treatment is 5.0m3/hr. The quality of water supply shall meet the standard of "Drinking Water Hygienic Standard (GB5749-2022)". As shown in Figure 1, Figure 2, and Figure 3, the water purification steps are as follows: river water enters the coagulation tank 1 at a flow rate of 5.0m3/h as raw water (natural flow water containing algae), and the raw water and flocculant pass through the coagulation tank for a certain period of time. The reaction of time forms a coagulant with granular alum flowers. The coagulation liquid enters the circulating slag removal box 2, and a partition 5 is set between the water inlet pipe 3 and the water outlet pipe 4 of the circulating slag removal box. The return pipe 6 enters the middle part of the coagulation tank 1. After the gas-dissolving liquid enters the coagulation tank 1, due to the pressure drop, the gas originally dissolved in the gas-dissolving liquid is released to form tiny bubbles, and the bubbles will dissolve the gas-dissolving liquid and lighter particles in the raw water. Float up to the surface of the concrete tank, and the scum is discharged through the slag discharge pipe 7 on the top of the tank. At the same time, due to the driving effect of the air bubbles, the raw water flows upwards, overturns the partition, and then flows downwards into the outlet pipe 4. Due to the action of the air bubbles, the water volume raised is much greater than the water outlet, and the remaining water continues to flow downward, and is transferred from the space at the bottom of the partition to the raw water inlet. side, so that the upper and lower circulation in the coagulation tank is conducive to the uniform stirring of the flocculant. Due to the effect of the circulation, some of the heavier particles are brought to the bottom of the coagulation tank and discharged through the mud discharge pipe 9. After deslagging, the clear liquid is uniformly mixed with ozone through the gas-liquid mixing pump 10. Under pressure, part of the ozone dissolves into the flocculation liquid, and part of the bubbles are evenly distributed in the flocculation liquid to form a gas-water mixture. The gas-water mixture enters from the bottom of the purifier 12, and the gas-water rises evenly and enters the purification channel 13 of the ultrafiltration membrane. The ultrafiltration membrane adopts a ceramic membrane, and the purified water flows out from the water purification pipe 14 through the ceramic membrane under pressure, and the flow rate is: 5.0m3/h. The concentrated liquid (flow rate: 0.50m3/h) and gas retained by the membrane wash along the membrane surface, gather in the return pipe 6, and return to the front-end circulation slag removal box 2. After purification, the turbidity of the effluent water is below 1NTU, meeting the requirements of the Sanitary Standard for Drinking Water (GB5749-2022).

Claims (3)

1. A natural running water ozone ultrafiltration membrane water purification treatment method is characterized by comprising the following steps:

s1, injecting self-flowing water containing algae into a coagulation box, adding a flocculating agent into the coagulation box, and reacting for a certain time to obtain mixed condensate;

s2, enabling the coagulating liquid to enter a circulating slag removal box, wherein a partition plate is arranged in the circulating slag removal box, a slag discharge pipe is arranged at the upper part of the circulating slag removal box, a mud discharge pipe is arranged at the bottom of the circulating slag removal box, the coagulating liquid forms a vertical circulating flow in the circulating slag removal box, algae floats are discharged by the slag discharge pipe, and sediment is discharged from the mud discharge pipe at the bottom of the circulating slag removal box; discharging the clear liquid obtained after deslagging from a water outlet pipe in the middle of the circulating deslagging box, and mixing the clear liquid with ozone through a gas-liquid mixing pump to form a gas-water mixture;

s3, filtering the air-water mixture by a self-cleaning filter, and then enabling the air-water mixture to enter an ultrafiltration membrane purifier; purified water filtered by the ultrafiltration membrane purifier flows out of a purified water pipe at the upper part of the ultrafiltration membrane purifier, and solution gas and solution formed in front of the ultrafiltration membrane flows back to the circulating slag removal box through a return pipe.

2. The method for purifying water by using natural running water and ozone ultrafiltration membrane according to claim 1, wherein the method comprises the following steps: the floating force on algae and scum in the circulating slag removal box is generated by releasing dissolved gas from the dissolved gas liquid entering through the return pipe.

3. The method for purifying water by using natural running water and ozone ultrafiltration membrane according to claim 1, wherein the method comprises the following steps: the ultrafiltration membrane is a ceramic ultrafiltration membrane or a silicon carbide ultrafiltration membrane or a PTFE ultrafiltration membrane or a PVDF ultrafiltration membrane.

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