CN103523875A - Method for killing limnoperna fortune in long-distance raw water delivery pipeline by combined effect of chlorine dioxide and sodium hypochlorite - Google Patents

Abstract

The invention discloses a method for killing freshwater shellfish in a long-distance raw water delivery pipeline through combined action of chlorine dioxide and sodium hypochlorite, relating to a method for killing freshwater shellfish in a raw water delivery pipeline. In the present invention, chlorine dioxide and sodium hypochlorite are added to long-distance raw water pipelines at 25°C for 3 to 7 days, and the concentration of chlorine dioxide per liter of raw water is controlled to be 1 to 3 mg/L, and sodium hypochlorite The concentration is 1~5mg/L. In the present invention, chlorine dioxide is added to the raw water delivery pipeline to kill the freshwater shellfish, and sodium hypochlorite can dissolve the foot silk, prompting it to fall off and remove it from the pipeline, so as to solve the problem that the freshwater shellfish is harmful to the water delivery of the water delivery pipeline. question. In addition, chlorine dioxide can also play a role in sterilizing and killing algae, and can decompose the residual cell structure. It has the effect of killing spores and killing viruses, which is beneficial to the subsequent water treatment process. The invention can effectively control the quantity of raw water and freshwater shell vegetables in pipelines, has safe and convenient operation, and has extremely high feasibility.

Description

Method for killing freshwater shellfish in long-distance raw water pipeline through combined action of chlorine dioxide and sodium hypochlorite

technical field

The invention relates to a method for killing freshwater shellfish in a raw water delivery pipeline, in particular to a method for killing freshwater shellfish in a long-distance raw water delivery pipeline through the joint action of chlorine dioxide and sodium hypochlorite.

Background technique

The deterioration of water quality and biofouling caused by freshwater shellfish to water pipelines are new problems in the water supply system in southern my country. Freshwater shellfish is a freshwater shell native to Asia, belonging to the phylum Molluscs in zoology, and the family Mytilidae of the bivalve Heterocolumnares. The distribution and damage caused by freshwater shellfish has been reported in many countries. Freshwater shellfish has strong adhesion ability, and it is easy to grow in large quantities on the inner wall of the water pipeline, which threatens the operation of the project and also brings potential danger to the water transfer across the basin. Therefore, the control of freshwater shellfish is of great significance.

Chlorine dioxide and sodium hypochlorite are commonly used oxidants in water treatment, and experiments have shown that both of them can effectively kill freshwater shellfish. When the concentration of chlorine dioxide in the raw water is 1~10mg/L, it can kill 50%~100% of freshwater shell vegetables. At the same time, chlorine dioxide not only has general bactericidal and algae killing effects, but also can decompose residual cells. structure, and also has the effect of killing spores and killing viruses, which is beneficial to the subsequent water treatment process. And sodium hypochlorite has the performance of dissolving silk, can promote the shedding of freshwater shell vegetables in the water pipeline, and prevent the pipeline from being blocked. Although chlorine dioxide has a good effect of killing freshwater shellfish, the concentration of chemicals required to be added is large, and it is difficult for sodium hypochlorite solution to maintain a high concentration in water for a long time. Although it can be seen that a single oxidant can achieve the purpose of killing freshwater shellfish, each has its own advantages and disadvantages, and still needs a method for killing freshwater shellfish that is more suitable for practical engineering applications.

Contents of the invention

In order to solve the existing problems of using a single oxidant to kill freshwater shell vegetables in raw water pipelines, the dosage is large and the economic cost is high, the present invention provides a combination of chlorine dioxide and sodium hypochlorite to kill The method of freshwater shellfish, this method is applicable to the extermination of freshwater shellfish in long-distance water pipelines in southern my country.

The object of the present invention is achieved through the following steps:

At 25°C, add chlorine dioxide and sodium hypochlorite to the long-distance raw water pipeline for 3 to 7 days, control the concentration of chlorine dioxide per liter of raw water to 1 to 3 mg/L, and the concentration of sodium hypochlorite to 1～5mg/L, complete the method that chlorine dioxide and sodium hypochlorite jointly kill the freshwater shellfish in the raw water delivery pipeline.

In the above method, when the concentration of chlorine dioxide in the raw water reaches 1 mg/L and the concentration of sodium hypochlorite reaches 1 mg/L, and the continuous dosing for 3 to 5.5 days, the mortality rate of freshwater shellfish reaches more than 70%.

In the above method, when the concentration of chlorine dioxide in the raw water reaches 1 mg/L and the concentration of sodium hypochlorite reaches 3 mg/L, and the continuous dosing for 1.5 to 2.5 days, the mortality rate of freshwater shellfish reaches more than 70%.

In the above method, when the concentration of chlorine dioxide in the raw water reaches 3 mg/L and the concentration of sodium hypochlorite reaches 1 mg/L, and the continuous dosing for 5 to 7 days, the mortality rate of freshwater shellfish reaches more than 70%.

In the above method, the concentration of chlorine dioxide in each liter of raw water is controlled to reach 1~3mg/L, the concentration of sodium hypochlorite reaches 1~5mg/L, the continuous dosing time of chlorine dioxide and sodium hypochlorite is 3~7 days, and the mortality rate of freshwater shellfish Reach more than 70%.

When chlorine dioxide acts alone, at a concentration of 1mg/L, the mortality rate of freshwater shellfish is only 60% after 14 days of continuous dosing. 70%. When sodium hypochlorite acts alone, after 15 days, the mortality rates at concentrations of 1 mg/L, 3 mg/L, and 5 mg/L are 35%, 70%, and 95%, respectively. It can be seen that compared with the use of chlorine dioxide or sodium hypochlorite alone to kill freshwater shellfish, when the two oxidants act at the same time, the effect is better than each oxidant acting alone, and the dosage of chemicals can be saved.

The invention combines the advantages of chlorine dioxide and sodium hypochlorite in killing freshwater shell vegetables: adding chlorine dioxide to the raw water delivery pipeline can kill freshwater shell vegetables, and sodium hypochlorite can dissolve the foot silk, prompting it to fall off, and then making it It is removed from the pipeline to solve the problem that the freshwater shellfish harms the water delivery function of the water delivery pipeline. In addition, chlorine dioxide can also play a role in sterilizing and killing algae, and can decompose the residual cell structure. It also has the effect of killing spores and killing viruses, which is beneficial to the subsequent water treatment process. The invention can effectively control the quantity of raw water and freshwater shell vegetables in pipelines, and the technology is safe and convenient to operate, and has extremely high feasibility.

Detailed ways

The technical solution of the present invention will be further described below in conjunction with specific embodiments, but it is not limited to this. Any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention should be covered by the present invention within the scope of protection.

Specific implementation mode 1: Taking the long-distance water delivery pipeline in southern China with a water supply flow rate of 500m ³ /h or more, a pipeline diameter of 400mm or more, and a water delivery distance of 5km or more as an example, in this implementation mode, the combined action of chlorine dioxide and sodium hypochlorite kills The method of freshwater shellfish in the raw water delivery pipeline is realized through the following steps: Dosing chlorine dioxide and sodium hypochlorite in the raw water delivery pipeline under the condition of 25 ℃, continuously dosing for 3 to 5.5 days, controlling the temperature per liter of raw water When the concentration of chlorine dioxide reaches 1mg/L, the concentration of sodium hypochlorite reaches 1mg/L, the mortality rate of freshwater shellfish reaches more than 70%, and the mortality rate of freshwater shellfish reaches 100% on the 5.5th day.

Specific implementation mode 2: Dosing chlorine dioxide and sodium hypochlorite into the raw water pipeline at 25°C for 1.5 to 2.5 days, controlling the concentration of chlorine dioxide per liter of raw water to 1 mg/L, and the concentration of sodium hypochlorite to 1 mg/L. 3mg/L, the mortality rate of freshwater shellfish reached more than 60%, and the mortality rate of freshwater shellfish reached 100% on the 2.5th day.

Specific implementation method three: Dosing chlorine dioxide and sodium hypochlorite into the raw water pipeline at 25°C for 5 to 7 days in a row, controlling the concentration of chlorine dioxide per liter of raw water to 1 mg/L, and the concentration of sodium hypochlorite to 1 mg/L. 5mg/L, the mortality rate of freshwater shellfish reaches 70~85%.

Embodiment 4: Dosing chlorine dioxide and sodium hypochlorite into the raw water pipeline at 25°C for 6 to 7 days, controlling the concentration of chlorine dioxide in the raw water to 3 mg/L and the concentration of sodium hypochlorite to 1 mg/L L, the mortality rate of freshwater shellfish reaches more than 70%.

Embodiment 5: Dosing chlorine dioxide and sodium hypochlorite into the raw water delivery pipeline at 25°C for 5.5 to 7 days, controlling the concentration of chlorine dioxide in the raw water to 3 mg/L and the concentration of sodium hypochlorite to 3 mg/L L, the mortality rate of freshwater shellfish reaches more than 70%.

Specific embodiment six: Dosing chlorine dioxide and sodium hypochlorite into the raw water delivery pipeline at 25°C for 5 to 7 days, controlling the concentration of chlorine dioxide in the raw water to 1 mg/L and the concentration of sodium hypochlorite to 5 mg/L L, the mortality rate of freshwater shellfish reaches more than 70%.

Claims (7)

1. The method for the joint action of chlorine dioxide and sodium hypochlorite to kill freshwater shell vegetables in long-distance raw water delivery pipelines, characterized in that the method steps are as follows: in the case of 25°C, add Chlorine dioxide and sodium hypochlorite are continuously added for 3 to 7 days, and the concentration of chlorine dioxide per liter of raw water is controlled at 1 to 3 mg/L, and the concentration of sodium hypochlorite at 1 to 5 mg/L. 2. according to claim 1, chlorine dioxide and sodium hypochlorite combined action kill the method of freshwater shellfish in the long-distance raw water delivery pipeline, it is characterized in that described adding time is 3～5.5 days, and chlorine dioxide concentration is 1mg/L, the concentration of sodium hypochlorite is 1mg/L. 3. according to claim 1, chlorine dioxide and sodium hypochlorite combine to kill the method of freshwater shellfish in the long-distance raw water delivery pipeline, it is characterized in that described dosing time is 1.5～2.5 days, and chlorine dioxide concentration is 1mg/L, the concentration of sodium hypochlorite is 3mg/L. 4. according to claim 1, chlorine dioxide and sodium hypochlorite combine to kill the method of freshwater shellfish in the long-distance raw water delivery pipeline, it is characterized in that described dosing time is 5～7 days, and chlorine dioxide concentration is 1mg/L, the concentration of sodium hypochlorite is 5mg/L. 5. according to claim 1, chlorine dioxide and sodium hypochlorite combine to kill the method for freshwater shellfish in long-distance raw water delivery pipeline, it is characterized in that described dosing time is 6～7 days, and chlorine dioxide concentration is 3mg/L, the concentration of sodium hypochlorite is 1mg/L. 6. according to claim 1, chlorine dioxide and sodium hypochlorite combine to kill the method of freshwater shellfish in the long-distance raw water delivery pipeline, it is characterized in that described dosing time is 5.5～7 days, and chlorine dioxide concentration is 3mg/L, the concentration of sodium hypochlorite is 3mg/L. 7. according to claim 1, chlorine dioxide and sodium hypochlorite combine to kill the method for freshwater shellfish in long-distance raw water delivery pipeline, it is characterized in that described dosing time is 5～7 days, and chlorine dioxide concentration is 1mg/L, the concentration of sodium hypochlorite is 5mg/L.