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

Natural running 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 running water ozone ultrafiltration membrane water purification treatment method.

Background

Sanitary standards for drinking water (GB 5749-2022) were issued in month 3 of 2022 and were carried out in month 1 of 2023. The standard eliminates the temporary regulations of the water quality indexes and limit values of the small centralized and decentralized water supply parts, which means that the water quality of urban and rural water supply needs to be uniform. And higher requirements are put on the quality of small-sized centralized and decentralized water supplies. The small centralized and decentralized water supply is mainly distributed in rural areas, pasture areas, mining areas and factories matched with municipal pipe networks far away from towns, and has the characteristics of poor water quality of water sources, easy explosion of algae and large seasonal change in natural conditions, and management is lack of professional management staff. So that the traditional coagulation, precipitation and sand filtration processes are difficult to reach the standard stably. The ultrafiltration membrane treatment water purification treatment method has the advantages of low turbidity of purified water and better water quality, thereby attracting attention. However, the conventional full-flow ultrafiltration membrane water purification process has higher pretreatment requirements on raw water, otherwise membrane holes are easy to be blocked to influence normal use. Cross flow filtration can solve the problem of membrane hole blockage, but has high energy consumption and high operation cost, so that the membrane hole blockage is difficult to popularize and use. A water purification treatment process with high algae removal efficiency, strong anti-fouling capacity and simple pretreatment operation is urgently needed. The self-cleaning filter is a precise device which directly intercepts impurities, floaters, particles and the like in liquid by utilizing a filter screen, reduces the turbidity of water, reduces dirt, ensures the normal operation and the service life of the following equipment, and has the characteristic of automatic pollution discharge.

Disclosure of Invention

The invention aims to solve the technical problem of providing an ultrafiltration membrane water purification process with high algae removal efficiency, strong anti-fouling capacity and simple pretreatment operation.

In order to solve the technical problems, the invention adopts the following technical scheme, and the method for treating the water by using the natural running water ozone ultrafiltration membrane is characterized by comprising the following steps of:

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.

Further, the upward floating force of 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.

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

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

As shown in figures 1, 2 and 3, the invention firstly mixes algae-containing natural running water and flocculant uniformly through a coagulation box to form coagulation liquid with alum blossom. The mixed condensate enters the circulating slag removal box 2, a baffle 5 is arranged between a water inlet pipe 3 and a water outlet pipe 4 of the circulating slag removal box to block, the reflowed dissolved gas and liquid enter the middle part of the circulating slag removal box 2 through a backflow pipe 6 positioned above the water inlet pipe 3, after the dissolved gas and liquid enter the circulating slag removal box 2, due to pressure reduction, gas originally dissolved in the dissolved gas and liquid is released to form tiny bubbles, the bubbles float lighter particles in the dissolved gas and liquid and algae-containing natural running water to the upper part of the circulating slag removal box 2, and scum is discharged through a slag discharge pipe 7 at the top of the circulating slag removal box 1. Meanwhile, due to the driving action of the bubbles, the coagulation liquid flows upwards and turns over the partition plate and then flows downwards to enter the water outlet pipe 4, and due to the action of the bubbles, the lifted water quantity is far greater than the water outlet quantity, the residual water quantity continues to flow downwards and turns into the inlet side of the water inlet pipe 3 from the space at the bottom of the partition plate, so that the up-and-down circulation formed in the circulating slag removal box 1 is beneficial to uniform stirring of the flocculant. Due to the circulation, part of the heavier particles are carried to the bottom of the circulation deslagging tank 2 and discharged through a sludge discharge pipe 9.

The clear liquid obtained after deslagging is evenly mixed with ozone through a gas-liquid mixing pump 10, part of ozone is dissolved into flocculating liquid under the pressure condition, and the ozone is evenly distributed in the flocculating liquid in the form of bubbles to be dispersed to form gas-water mixed liquid. The gas-water mixed solution is filtered by a self-cleaning filter 11, enters from the bottom of an ultrafiltration membrane purifier 12, and then uniformly rises to enter an ultrafiltration membrane purification channel 13. The filtered purified water flows out of the purified water pipe 14 under pressure. The concentrated solution and gas trapped by the ultrafiltration membrane are flushed along the membrane surface and are converged at a return pipe 6 to return to the circulating slag removal box 2.

The invention utilizes the strong oxidizing ability of ozone and the stirring action of airflow to alleviate the problems of scaling and fouling on the surface of the ultrafiltration membrane.

According to the invention, ozone dissolved in the dissolved gas and liquid is utilized to kill algae on one hand, and the pressure is reduced to release gas so as to float algae and lighter scum on the other hand, so that the algae removal effect of pretreatment before ultrafiltration is improved.

According to the invention, the clear liquid and the ozone are pumped into the ultrafiltration membrane purifier 12 through the gas-liquid mixing pump 11, so that on one hand, the ozone and the clear liquid are uniformly mixed in the pipeline, and on the other hand, the gas-water mixed liquid can be lifted and pressurized, so that the problem that the natural running water does not have pressure or is insufficient in pressure is solved.

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

In conclusion, the invention has the beneficial effects of high algae removal efficiency, strong anti-fouling and blocking capacity, simple pretreatment operation and the like.

Drawings

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

Fig. 2 is a schematic structural view of the circulation deslagging box.

FIG. 3 is a schematic diagram of the structure of an ultrafiltration membrane purifier.

Description of the embodiments

The invention relates to an ultrafiltration membrane water purification treatment method for natural flow algae-laden raw water, which is further described by referring to the accompanying drawings, and the invention is further described by referring to the following examples:

example 1: for rural water supply systems in certain plain areas, the turbidity of raw water is 15-200 NTU, seasonal algae burst is carried out, the daily water supply is 100m < 3 >/d, and the treatment is carried out according to 5.0m < 3 >/hr. The water quality of the water supply meets the standard of sanitary standard for drinking water (GB 5749-2022). As shown in fig. 1, 2 and 3, the water purification steps are as follows: river water as raw water (natural running water containing algae) enters the coagulation tank 1 at a flow rate of 5.0m3/h, and the raw water reacts with the flocculant in the coagulation tank for a certain time to form coagulation liquid with granular alum flowers. The mixed condensate enters the circulating slag removal box 2, a baffle 5 is arranged between a water inlet pipe 3 and a water outlet pipe 4 of the circulating slag removal box to block the mixed condensate, the reflowed dissolved gas and liquid (the flow rate is 0.50m < 3 >/h) enters the middle part of the coagulation box 1 through a backflow pipe 6 positioned above a raw water inlet pipe 3, after the dissolved gas and liquid enters the coagulation box 1, the gas originally dissolved in the dissolved gas and liquid is released to form tiny bubbles due to pressure reduction, the bubbles float the dissolved gas and lighter particles in the raw water to the surface of the coagulation box, and the scum is discharged through a slag discharge pipe 7 at the top of the pool. Meanwhile, the raw water flows upwards and turns over the partition plate under the driving action of the bubbles and then flows downwards to enter the water outlet pipe 4, the water quantity lifted under the action of the bubbles is far greater than the water yield, the residual water quantity continues to flow downwards and is transferred to the raw water inlet side from the space at the bottom of the partition plate, and therefore, the up-and-down circulation is formed in the coagulation tank, and uniform stirring of the flocculant is facilitated. The particles, which are heavier due to the action of the circulation, are carried to the bottom of the coagulation tank and discharged through the sludge discharge pipe 9. The clear liquid after deslagging is evenly mixed with ozone through a gas-liquid mixing pump 10, part of ozone is dissolved into flocculating liquid under the condition of pressure, and part of bubbles are evenly distributed in the flocculating liquid to be dispersed to form gas-water mixed liquid. The gas-water mixed solution enters from the bottom of the purifier 12, and the gas-water uniformly rises to enter the ultrafiltration membrane purification channel 13. The ultrafiltration membrane adopts a ceramic membrane, and the purified water flows out from the water purification pipe 14 through the ceramic membrane under the pressure effect, and the flow is 5.0m3/h. The concentrate (flow: 0.50m 3/h) and gas trapped by the membrane are flushed along the membrane surface and collected in a return pipe 6, and returned to the front-end circulation deslagging tank 2. The turbidity of the purified effluent is less than 1NTU, and meets the requirements of sanitary Standard for Drinking Water (GB 5749-2022).

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.

Images