A method for killing red worms in sewage treatment and a biochemical pool device

Abstract

The present invention provides a method and apparatus for killing red worms in sewage treatment. The method includes both online and offline killing. The online killing is performed when the biochemical system of a sewage treatment plant cannot be shut down for a short period of time, maintaining the required killing period HRT of the biochemical system at least 4 hours. The offline killing is performed when the biochemical system of a sewage treatment plant undergoes short-term maintenance or shutdown. The present invention utilizes a specific biochemical environment regulator to effectively disinfect red worms in sewage treatment, an innovative solution that does not affect the normal operation of the sewage treatment plant. Furthermore, the method is simple to operate, has a high killing rate, and has no impact on other microorganisms or effluent water quality. Furthermore, the present invention uses a very small dosage of the biochemical environment regulator to kill red worms, achieving a killing rate of up to 98%.

Description

Technical Field

[0001] The invention relates to the application field of preventing and controlling red worms from polluting the environment, and in particular to a red worm killing method and a biochemical pool device used in sewage treatment. Background Art

[0002] Bloodworms are a common type of benthic oligochaete in natural water bodies, widely distributed in rivers, ditches and other water bodies. Due to their strong migration ability, bloodworms can migrate from the benthic environment to the overlying water, and then enter the sewage treatment plant with the raw water. Similarly, bloodworms are also common metazoans in sewage treatment biochemical systems.

[0003] Red worms mainly reproduce by preying on bacteria and sludge fragments in activated sludge. However, when the environment of the biochemical system changes significantly, red worms will multiply in large numbers. A large number of red worms will eat up most of the nitrifying bacteria in the biochemical system, causing the nitrification system to collapse. At the same time, it will cause the ammonia nitrogen content in the sewage treatment plant's effluent to exceed the standard continuously and seriously, causing serious impacts on the ecological environment.

[0004] According to the document "Research on the Causes, Inactivation Methods and Removal Technologies of Red Worms and Red Nematodes in Reclaimed Water" and actual surveys of several sewage treatment plants with red worm outbreaks, the following two methods are basically adopted after a large-scale outbreak of red worms: a. Stop the water inlet, backflow and aeration of the sewage treatment plant's biochemical system. The biochemical system will be shut down for 48 hours, which can kill about 99% of the red worms. It takes about 48 hours for the biochemical system to return to normal treatment status. Due to the long downtime and recovery time, the production and operation of the sewage treatment plant is seriously affected; b. Stop the water inlet, backflow and aeration of the sewage treatment plant's biochemical system, and add chemical agents such as sodium hypochlorite, calcium hydroxide and potassium permanganate to kill all bacteria and microorganisms in the biochemical system. The killing time is about 8 hours, and the required recovery time is 72 hours to 120 hours, which has a serious impact on the production and operation of the sewage treatment plant.

[0005] In addition, there are also physical treatment methods using ultrasound-ozone to kill red worms in the prior art. For example, the water treatment method for killing red worms using ultrasound-ozone disclosed in CN101643268A is as follows: pre-ozone is introduced into the raw water before conventional treatment, with an ozone injection amount of 1-2 mg per liter of raw water. At the same time, ultrasound with a frequency of 50 Hz, an ultrasonic power of 120 W, and an action time of 10-20 minutes is used. All the red worms in the treated raw water are killed and are thoroughly and effectively removed in the subsequent coagulation, sedimentation, and filtration water treatment processes. However, the defects of the ultrasound-ozone treatment method are also very obvious. First, red worms are also metazoans in the biochemical system and are not entirely brought into the sewage treatment system by the incoming water. Therefore, this solution cannot completely solve the problem of red worms in the biochemical system. Secondly, this solution cannot be used in a biochemical treatment unit because it will simultaneously kill other microorganisms and bacteria in the biochemical system, thereby causing the biochemical system to collapse. In addition, this solution is costly and has a high safety risk.

[0006] Therefore, without affecting the normal operation of the sewage treatment plant, it is an urgent problem to seek a method for killing red worms that is simple to operate, has a high killing rate, and has no effect on other microorganisms and effluent water quality. Summary of the Invention

[0007] The present invention provides a method and apparatus for killing red worms in sewage treatment. The method utilizes both online and offline methods to kill red worms, tailored to the actual operation of sewage treatment plants. A biochemical system environmental regulator is added to the biochemical tank in an appropriate dosage. The method and apparatus can kill over 98% of red worms without affecting other microorganisms in the biochemical tank or the effluent quality. The method and apparatus are simple to operate and suitable for large-scale industrial use.

[0008] The technical solutions of the present invention are as follows:

[0009] The present invention provides a method for killing red worms in sewage treatment, which includes online killing and offline killing. The online killing is performed when the biochemical system of the sewage treatment plant cannot be shut down for a short period of time, and the killing period HRT required by the biochemical system is maintained at ≥4h. The main operation includes the following steps:

[0010] Step S1: diluting the biochemical system environment regulator with water at a ratio of 1:20 to 1:100;

[0011] Step S2: Sprinkling the diluted ecosystem environment regulator on the aerobic tank liquid level of the biochemical pool in a manner of gradually decreasing dosage from the water inlet end to the water outlet end of the biochemical pool at a dosage of 1ppm-3ppm;

[0012] The offline killing is used for the biochemical system of the sewage treatment plant during short-term maintenance or shutdown, and includes the following steps:

[0013] Step T1: diluting the biochemical system environmental regulator with water at a ratio of 1:20 to 1:100;

[0014] The biochemical system environment regulator comprises 2-10 wt% of emamectin benzoate, 0.35 wt% of D902 stabilizer, 3.3 wt% of MgSO4.7H2O, 15 wt% of C6H 12 O6, 0.5 wt% CuSO4 content, 0.3 wt% ZnSO4.7H2O, 3 wt% KCl;

[0015] Step T2: closing the sewage inlet of the biochemical pool and introducing air into the biochemical pool;

[0016] Step T3: Sprinkle the diluted ecosystem environment regulator on the aerobic pool liquid level of the biochemical pool in a manner of gradually decreasing dosage from the water inlet end to the water outlet end of the biochemical pool according to the dosage of 1ppm-3ppm.

[0017] Furthermore, in the online or offline killing, when the water temperature is above 20°C, the dosage of the agent is 1ppm-2ppm according to the actual situation, and when the water temperature is below 20°C, the dosage of the agent needs to be maintained at 2ppm-3ppm.

[0018] Furthermore, in step S1 or T1, the dosage is calculated based on the undiluted stock solution of the biochemical system regulator.

[0019] Furthermore, in step S1 or T1, the prepared and water-diluted medicine should be used immediately, otherwise the effect will be affected.

[0020] Furthermore, in step T2, the flow rate of the air is adjusted according to different pipe diameters and required air volumes designed for different projects.

[0021] Furthermore, in step S2 or T3, when the water temperature is above 20°C, the dosage of the agent is 1ppm-2ppm according to the actual situation, and when the water temperature is below 20°C, the dosage of the agent needs to be maintained at 2ppm-3ppm.

[0022] Furthermore, the online killing also includes step S3, observing the killing of red worms about 2 hours after the killing is completed, achieving a killing rate of more than 98%, and having no impact on other microorganisms in the biochemical pool and the water quality of the effluent.

[0023] Furthermore, the offline killing also includes step T4, which is to observe the killing of red worms about 2 hours after the offline killing is completed, and achieve a killing rate of more than 98%, without affecting other microorganisms in the biochemical pool and the water quality of the effluent.

[0024] Furthermore, the offline killing further includes step T5, restoring the normal operation of the biochemical pool.

[0025] The present invention also provides a biochemical pool device for implementing the above-mentioned method for killing red worms, wherein the biochemical pool device comprises the following components:

[0026] Aerobic treatment pool is the main space for online or offline killing of red worms using biochemical system environmental regulators in sewage treatment.

[0027] Inlet pipe, used to introduce sewage, sewage flow rate is 1-10000m 3 / h;

[0028] The air inlet pipe is used to let in air to oxygenate the aerobic pool.

[0029] Outlet pipe, used to discharge treated sewage,

[0030] Sludge discharge pipe, used for residual sludge discharge,

[0031] Return pump, used for sludge return and lifting in the back-end clarification process of the aerobic tank.

[0032] Return pipe, used for sludge return.

[0033] The present invention has the following beneficial effects:

[0034] 1. The present invention provides an innovative solution for effectively disinfecting red worms in sewage treatment using specific biochemical environment regulators, including online and offline killing. On the one hand, it does not affect the normal operation of the sewage treatment plant. On the other hand, it is easy to operate, has a high killing rate, and has no impact on other microorganisms and effluent water quality.

[0035] 2. The present invention uses a biochemical environment regulator with a very small dosage (dilution ratio of 20 times, dosage of 1ppm-3ppm) to kill red worms, but the killing rate is as high as 98%. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a structural schematic diagram of the ecological pond device of the present invention.

[0037] 1——Aerobic treatment tank

[0038] 2--water inlet pipe

[0039] 3-Intake pipe

[0040] 4——Water outlet pipe

[0041] 5——Aerobic pool liquid level

[0042] 6——Biochemical system environmental regulator

[0043] 7——mud discharge pipe

[0044] 8——Return pump

[0045] 9——Return pipe DETAILED DESCRIPTION

[0046] The invention is described in detail below with reference to the embodiments:

[0047] Example

[0048] Embodiment 1:

[0049] When the water inflow of the biochemical system of the sewage treatment plant is within the normal design water volume range and the operation cannot be stopped for a short period of time, the red worms can be killed by online disinfection. The specific steps are as follows:

[0050] Step S1

[0051] Dilute the biochemical system environmental regulator 6 with tap water at a ratio of 1:20;

[0052] Step S2

[0053] According to the dosage of 1ppm-3ppm (calculated based on the original solution of the undiluted biochemical system regulator 6), the diluted solution is sprinkled on the aerobic pool liquid level 5 in a manner of gradually decreasing dosage from the water inlet end to the water outlet end of the biochemical pool;

[0054] Step S3

[0055] About 2 hours after the killing is completed, observe the killing of red worms. According to actual experience, more than 98% of the red worms can be killed without affecting other microorganisms in the biochemical pool or the water quality of the effluent.

[0056] Step S4

[0057] No adjustments are required, continue normal operation.

[0058] Example 2

[0059] When the biochemical system of the sewage treatment plant is under short-term maintenance or shutdown, the method of offline disinfection is used to kill red worms. The specific steps are as follows:

[0060] Step T1

[0061] Dilute the biochemical system environmental regulator 6 with tap water at a ratio of 1:20;

[0062] Step T2

[0063] Close the water inlet pipe 2 of the biochemical pool, stop the reflux pump 8, and keep the air inlet pipe 3 open;

[0064] Step T3

[0065] According to the dosage of 1ppm-3ppm (calculated based on the original solution of undiluted biochemical system regulator 6), the amount of the regulator is gradually reduced from the inlet end to the outlet end of the biochemical pool, and the aerobic pool liquid level 5 of the biochemical pool is poured.

[0066] Step T4

[0067] Let it stand for 2 hours, and then observe the killing of red worms. According to actual experience, more than 99% of red worms can be killed without affecting other microorganisms in the biochemical pool or the water quality of the effluent.

[0068] Step T5

[0069] No recovery time is required, the water inlet pipe 2 can be opened directly to inlet water and the reflux pump 8 can be opened to reflux, and the aerobic treatment pool 1 can resume normal operation.

[0070] The solution of Example 1 or Example 2 has been used in a 450,000 m2 building in Changsha. 3 / d sewage treatment capacity has been put into practical use in sewage treatment plants with excellent results. Figure 1 The following is a comparison of before and after insecticide treatment. Before the treatment, a large number of red worms were found at the bottom of the cup. After the treatment, a sample was taken, and there were almost no red worms at the bottom of the cup.

[0071] The above description is merely a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any modification or equivalent variation based on the technical essence of the present invention shall still fall within the scope of protection claimed by the present invention.

Claims

1. A method for killing red worms in sewage treatment, characterized in that: The method includes online killing and offline killing. The online killing is used when the biochemical system of the sewage treatment plant cannot be stopped for a short period of time. During the killing, it is necessary to keep the HRT of the killing period required by the biochemical system ≥ 4h. The main operation includes the following steps: Step S1: diluting the biochemical system environment regulator with water at a ratio of 1:20 to 1:100; Step S2: adding a dosage of 1ppm-3ppm, which is calculated based on the undiluted original solution of the biochemical system regulator, and spraying the diluted biochemical system environment regulator onto the aerobic tank liquid level of the biochemical pool in a manner in which the dosage gradually decreases from the water inlet end to the water outlet end of the biochemical pool; The offline killing is used for the biochemical system of the sewage treatment plant during short-term maintenance or shutdown, and includes the following steps: Step T1: diluting the biochemical system environmental regulator with water at a ratio of 1:20 to 1:100; The biochemical system environment regulator comprises 2-10 wt% of emamectin benzoate, 0.35 wt% of D902 stabilizer, 3.3 wt% of MgSO4·7H2O, 15 wt% of C6H 12 O6, 0.5 wt% CuSO4 content, 0.3 wt% ZnSO4·7H2O, 3 wt% KCl; Step T2: closing the sewage inlet of the biochemical pool and introducing air into the biochemical pool; Step T3: According to the dosage of 1ppm-3ppm, the dosage is calculated based on the undiluted original solution of the biochemical system regulator, and the diluted biochemical system environment regulator is sprinkled on the aerobic pool liquid level surface of the biochemical pool in a manner in which the dosage gradually decreases from the water inlet end to the water outlet end of the biochemical pool.

2. The method for killing red worms according to claim 1, wherein In the online or offline killing, when the water temperature is above 20°C, the dosage of the agent is 1ppm-2ppm according to the actual situation, and when the water temperature is below 20°C, the dosage of the agent needs to be maintained at 2ppm-3ppm.

3. The method for killing red worms according to claim 1 or 2, wherein: In step S1 or T1, the prepared and water-diluted medicine should be used immediately, otherwise the effect will be affected.

4. The method for killing red worms according to claim 1 or 2, wherein: In step T2, the air flow rate is adjusted according to the different pipe diameters and required air volumes designed for different projects.

5. The method for killing red worms according to claim 1 or 2, wherein: In step S2 or T3, when the water temperature is above 20°C, the dosage of the agent is 1ppm-2ppm according to the actual situation, and when the water temperature is below 20°C, the dosage of the agent needs to be maintained at 2ppm-3ppm.

6. The method for killing red worms according to claim 1 or 2, wherein: The online killing also includes step S3, which is to observe the killing of red worms about 2 hours after the killing is completed, and achieve a killing rate of more than 98%, without affecting other microorganisms in the biochemical pool and the water quality of the effluent.

7. The method for killing red worms according to claim 1 or 2, wherein: The offline killing also includes step T4, which is to observe the killing of red worms about 2 hours after the offline killing is completed, and achieve a killing rate of more than 98%, without affecting other microorganisms in the biochemical pool and the water quality of the effluent.

8. The method for killing red worms according to claim 1 or 2, wherein: The offline killing further comprises step T5, restoring the normal operation of the biochemical pool.

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