Pollution source control and removal method for underground water organic pollution site

Abstract

The invention discloses a pollution source control and removal method for an underground water organic pollution site, and relates to the technical field of site remediation. Firstly, an underground water pollution source is controlled, and a waterproof curtain is built at the boundary of a polluted area. Then an underground water pollution source is removed in a polluted area excavation and ectopic treatment mode, and polluted underground water is collected through foundation pit dewatering in the excavation process and conveyed to wastewater treatment equipment to be treated; the excavated aquifer medium soil is subjected to ex-situ indirect thermal desorption treatment, adsorbed and residual organic pollutants in the soil medium are heated into a gas state to be separated from soil particles, and generated high-temperature waste gas is subjected to activated carbon adsorption treatment after being pretreated. By monitoring underground water around and inside the remediation area, an underground water pollution source is effectively controlled and removed, and the removal rate of soil and underground water pollutants after treatment is close to 100%. The method is thorough in underground water organic pollution site treatment and high in treatment efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of site remediation, and more particularly to a method for controlling and removing pollution sources in groundwater organic contaminated sites. Background Art

[0002] The main causes of organic pollution in groundwater are the direct discharge of industrial wastewater, agricultural wastewater and domestic sewage. In addition, industrial waste gas, smoke and dust emissions, etc., under the action of rainfall runoff, will also enter the groundwater with infiltration, causing groundwater pollution. Polluted groundwater has a significant impact on human health, economic development, social stability, etc., so the development of groundwater pollution control and remediation work is of great significance.

[0003] Polycyclic aromatic hydrocarbons are harmful to human bodies due to their mutagenic, teratogenic and carcinogenic effects. They also have poor degradation performance and strong migration performance. They are one of the common components of groundwater pollution. There is an adsorption / desorption reaction between dissolved organic pollutants and aquifer media in groundwater contaminated sites, which causes pollutants to pass through aquifer media much slower than water does, and there is a hysteresis in the passage of pollutants through aquifer media. Bedrock aquifers have a large number of fissures, and their effective fissure porosity range is generally 0.001%~0.1%, which is much smaller than the porosity range of typical loose rocks (20~40%). When pollutants enter bedrock aquifers, they mainly flow through interconnected fissures and stagnate at the dead end of the fissure system, and are stored in them by adsorption. Therefore, bedrock aquifer media have a stronger adsorption and interception effect on pollutants. At present, the remediation technologies that are widely used in groundwater organic contaminated sites include groundwater extraction treatment, in-situ chemical oxidation and barrier control. Barrier control technology only blocks the diffusion path of groundwater and fails to completely eliminate the source of pollution. In-situ chemical oxidation remediation has relatively poor remediation effects on groundwater contaminated sites in low permeability media, and pollutant rebound is prone to occur. Groundwater extraction and treatment technology is limited by hydrogeological conditions. Due to the interaction between the aquifer medium and the pollutants, the pollutants will be adsorbed and remain in the aquifer medium. As the pumping project proceeds, they are slowly released into the water, and tailing and rebound phenomena occur during the remediation process. Therefore, it takes a long time for groundwater extraction treatment to achieve the remediation goal in low permeability aquifers and bedrock fissure aquifers, and the remediation is not thorough. None of the above technologies can guarantee the remediation effect of groundwater organic contaminated sites. Summary of the invention

[0004] In order to solve the problems of incomplete remediation and treatment, and the hidden danger of pollutant concentration rebound in the current treatment process of groundwater organic pollution sites, a method for controlling and removing pollution sources of groundwater organic pollution sites is provided. This method achieves the goal of groundwater pollution site treatment by controlling and removing groundwater pollution sources, especially high-temperature thermal desorption treatment of aquifer medium soil, which solves the problems of incomplete remediation of groundwater organic pollution sites and the hidden danger of pollutant concentration rebound. At the same time, the treatment period is short, and it has important engineering application value.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] The present invention provides a new treatment method. First, a water-stop curtain is constructed around the polluted groundwater area to effectively control the groundwater pollution source, so as to avoid the change of the surrounding groundwater flow field and the spread of pollutants caused by the construction in the polluted groundwater area. Then, the groundwater pollution source is removed by excavation of the polluted area + ex situ disposal. The polluted groundwater collected during the excavation process is transmitted to the ground integrated water treatment equipment for repair; the excavated aquifer medium soil is transported to the ex situ thermal desorption disposal area, and indirect ex situ thermal desorption is used for treatment. The adsorbed and residual pollutants in the soil medium are heated into a gas form by the high temperature heating of the thermal desorption equipment to achieve separation from the soil particles, which can ensure that the adsorbed and residual pollutants in the aquifer medium soil are completely repaired to meet the requirements of later safe utilization.

[0007] A method for controlling and removing pollution sources in groundwater organic pollution sites, which controls groundwater pollution sources by building a water-stop curtain, and removes groundwater pollution sources by excavation + ex situ disposal on this basis, including the following steps:

[0008] (1) Control of groundwater pollution sources

[0009] 11) Review of pollution scope

[0010] Before the construction of the water-stop curtain, a monitoring well shall be built at the boundary of the groundwater remediation area and samples shall be taken for testing. Based on the test results of the groundwater, the scope of groundwater contamination shall be reviewed;

[0011] 12) Water-stop curtain construction

[0012] After the boundaries of the groundwater pollution area are determined, a water-stop curtain is constructed according to the ground conditions to control the groundwater pollution source;

[0013] (2) Elimination of groundwater pollution sources

[0014] 21) Excavation in groundwater contaminated areas

[0015] Excavate the designated area, collect contaminated groundwater during the excavation process and send it to the integrated treatment equipment for repair. The excavated aquifer medium soil is subjected to ex situ thermal desorption treatment. After the excavation is completed, the excavation effect of the foundation pit is inspected and accepted;

[0016] 22) Thermal desorption of soil in aquifer media

[0017] The soil from the aquifer medium in the contaminated groundwater area is transported to the thermal desorption treatment area for disposal. The contaminated soil is pre-treated, and large particles larger than 30 mm are screened out as slag, which is cleaned with high-pressure water flow; particles with a diameter less than 30 mm enter the thermal desorption system for disposal, and the high-temperature exhaust gas discharged during the thermal desorption treatment process is treated and monitored;

[0018] 23) Wastewater treatment

[0019] The contaminated groundwater collected during the excavation process and the wastewater generated during the thermal desorption treatment process are transported to the wastewater treatment facility and treated using a combined process of coagulation sedimentation → chemical oxidation → quartz sand filtration → activated carbon adsorption. After the treatment meets the standards, it is discharged into the pipeline;

[0020] (3) Determination of repair effect

[0021] After the contaminated groundwater collected through excavation and the wastewater generated during the thermal desorption treatment process are repaired, sampling and testing will be carried out in batches to ensure that all the wastewater has been repaired and qualified;

[0022] Take samples of the soil after thermal desorption treatment and test the pollutants to find out whether the pollutants are above the standard for groundwater, so as to ensure that the soil after thermal desorption treatment meets the requirements;

[0023] During the construction process, the groundwater around the repair area is monitored once a month through monitoring wells to ensure that the groundwater has not spread. After the groundwater and aquifer medium soil are cleaned, the groundwater inside the foundation pit is tested through monitoring wells to ensure that the groundwater removal target is achieved.

[0024] Preferably, the excavation in step 21) is performed by using a basin excavation method to excavate the designated area, that is, excavating from the middle of the foundation pit to the surrounding areas to ensure that groundwater flows to the center of the foundation pit during the construction process.

[0025] Preferably, the pretreatment in step 22) includes: crushing, screening and adjusting the soil moisture content.

[0026] Preferably, the operating temperature of the thermal desorption treatment in step 22) is 500-570°C, and the heating time is 20-30 minutes, so that the adsorbed and residual pollutants in the soil medium are heated into a gaseous form to be separated from the soil particles.

[0027] Preferably, the high-temperature exhaust gas discharged in the thermal desorption treatment in step 22) is first sprayed through a tail gas spray tower, the tail gas after the spraying treatment enters a condenser for condensation and is separated into gas and liquid through a gas-liquid separator, the tail gas after the gas-liquid separation is treated with activated carbon adsorption, and the liquid collected after the gas-liquid separation enters a water treatment device for disposal.

[0028] Preferably, the wastewater treatment in step 23) specifically includes:

[0029] The collected wastewater enters the integrated water treatment equipment for treatment. The integrated water treatment equipment is equipped with a flocculation sedimentation tank and an oxidation tank. The wastewater is pumped to the flocculation sedimentation tank, and alkali, coagulant and flocculant are added for coagulation and sedimentation. The sediment and suspended particles in the wastewater are combined into larger flocs, which are finally precipitated out. The mud and water are separated by the inclined plate sedimentation tank, and the supernatant is discharged into the oxidation tank. Chemical oxidation reaction is carried out in the oxidation tank. The supernatant of the oxidation tank is filtered through a sand filter and an activated carbon tank. After filtration, it enters the support water pool to be accepted for testing. If the test meets the standards, it will be discharged into the pipe.

[0030] It can be seen from the above technical solution that compared with the prior art, the present invention has the following beneficial effects:

[0031] First, by building a water-stop curtain around the polluted groundwater area, the groundwater pollution source is effectively controlled. The permeability of the cement mixing pile water-stop curtain is less than 1*10 -7 cm / s, combined with the monitoring of groundwater around the contaminated area once a month, the results are all up to standard, indicating that groundwater did not spread during the construction period, and the water-stop curtain meets the control requirements of groundwater pollution sources. The groundwater pollution source is removed by excavation of the contaminated area + ex situ disposal. The collected contaminated groundwater enters the integrated water treatment equipment for repair, and the treated wastewater meets the piped discharge standard; the aquifer medium soil is repaired by ex situ thermal desorption, and the adsorbed and residual pollutants in the soil medium are heated into gas form to separate from the soil particles. The removal effect of soil pollutants after disposal is close to 100%. At the same time, considering the high boiling point of the organic pollutant benzo(a)pyrene and the difficulty of removing pollutants adsorbed on the aquifer medium, the heating temperature and time of thermal desorption will be adjusted according to the characteristics of the pollutants through on-site pilot tests to achieve the treatment effect.

[0032] By monitoring the groundwater around and inside the restoration area, the present invention effectively controls and removes possible pollution sources in the groundwater contaminated area, eliminating the possibility of pollution, and the concentration of soil and groundwater pollutants after treatment is far lower than the restoration target value, and the restoration is complete. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0034] Figure 1 It is a flowchart for the implementation of the present invention;

[0035] Figure 2 It is the groundwater pollution range map of the site;

[0036] Figure 3 This is the cross-section of the water-stop curtain;

[0037] Figure 4 This is a flow chart of thermal desorption treatment;

[0038] Figure 5 Wastewater treatment flow chart. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Example 1

[0041] The present invention takes a pollution site in Zhejiang as an example to carry out a specific embodiment of a method for controlling and removing pollution sources of sewage organic pollution sites.

[0042] The site was originally a converter steel mill motor workshop and steelmaking workshop in the converter steel mill area. According to the results of the site environmental survey and risk assessment, there is groundwater contamination that exceeds the acceptable health risk and needs to be repaired. The groundwater contamination depth is 1-6m, and the main pollutant is benzo(a)pyrene, with an excessive concentration of 1.38ug / L. The groundwater remediation area is 2324m 2 The volume of soil in the groundwater pollution area that does not exceed the standard is 11620m 3. According to the site geological survey report, the soil layers in the groundwater contaminated area are mixed fill, strongly weathered rock layers, and moderately weathered rock layers. The rock layers are shallowly buried and the groundwater level is high. The groundwater is pore water in loose rocks and fissure water in bedrock. The site groundwater level is 7.7~9.3m. The pore groundwater is mainly replenished by atmospheric precipitation and surface water infiltration. The groundwater level changes dynamically with the seasons and climate. Generally, the change range is not large, with an annual range of 1.0~2.0m. The pollutants in the fissure water of the strongly weathered rock strata of this project are easy to stagnate in the dead end part of the fissure system and are stored in it by adsorption, which makes it more difficult to control. After the borehole water pressure test, the permeability coefficients of the moderately weathered sandstone were measured to be 5.31×10 -7 cm / s、9.53×10 -7 cm / s, 1.03×10-6cm / s, and the average permeability coefficient is 8.4×10 -7 cm / s, the medium-weathered sandstone has a low permeability and is an impermeable layer.

[0043] Table 1 Site investigation groundwater pollutant remediation target values ​​and engineering quantities

[0044] Plot Number Types of pollution Pollutants Pollution concentration (mg / L) Repair target value (mg / L) Pollution depth (m) <![CDATA[Pollution area (m 2 ).]]> <![CDATA[Thermal desorption engineering quantity (m 3 ))]]> W1 Groundwater exceeds the standard, soil does not exceed the standard Benzo(a)pyrene 0.00138 0.0005 1-6 m 2324 11620

[0045] According to the actual pollution situation of the site and the results of risk assessment, since the concentration of benzo(a)pyrene in the groundwater in the area involved exceeds the standard and the risk to human health exceeds the acceptable risk level, it is necessary to repair the groundwater in the area. The specific steps are as follows:

[0046] Step 1: Control of groundwater pollution sources

[0047] 1) Review of pollution scope

[0048] According to the requirements of the Technical Guidelines for Groundwater Remediation and Risk Control in Contaminated Land (HJ25.6) and the Technical Guidelines for Extraction and Treatment of Contaminated Groundwater (Trial), 5 monitoring wells were built around the treatment area and 3 monitoring wells were built within the treatment area before construction, and groundwater sampling and monitoring were completed before construction to verify the groundwater pollution. The test results of benzo(a)pyrene in the 5 groundwater monitoring wells around the pollution area were all lower than the detection limit of 0.004μg / L; the test results of the 3 groundwater monitoring wells within the pollution area were all greater than the remediation target value of 0.5μg / L, which was basically consistent with the field survey results, confirming the scope of groundwater remediation.

[0049] 2) Water-stop curtain construction

[0050] The excavation depth of the groundwater remediation area is 6m. Before excavation and remediation of this area, water-stop curtain and foundation pit support construction shall be carried out. The deep foundation pit support and water-stop curtain are in the form of cement mixing piles (Φ650mm) + slope support for the support structure. The cement mixing piles also serve as water-stop curtains (if the water-stop curtain encounters bedrock, it needs to penetrate 1m into the medium-weathered rock. The combination of cement mixing piles and medium-weathered rock constitutes the water-stop curtain system). After the water-stop curtain construction is completed, the permeability performance of the three-axis mixing pile core is tested. The test result is less than 1*10 -7 cm / s, the permeability coefficient of the water-stop curtain meets the design requirements and achieves the water-stop effect.

[0051] Step 2: Removal of groundwater pollution sources

[0052] 1) Excavation in groundwater contaminated areas

[0053] After the construction of the water-stop curtain is completed, the groundwater contaminated area is excavated in layers according to 0-1m, 1-2m, 2-4m, and 4-6m. The excavation is carried out in a basin-like manner, that is, excavation is carried out from the middle of the foundation pit to the surrounding areas to ensure that the groundwater converges to the center of the foundation pit during the construction process. The groundwater is collected through the water collection well at the bottom of the pit during the excavation process and transported to the surface water treatment facility for disposal. The soil in the groundwater contaminated area is excavated and transported to the thermal desorption disposal area for disposal. After the groundwater and aquifer medium soil are cleaned, the bottom and side walls of the foundation pit are inspected and the excavation effect meets the excavation acceptance target of the site.

[0054] 2) Thermal desorption remediation of aquifer medium soil

[0055] The soil of the aquifer medium in the contaminated groundwater area is transported to the thermal desorption disposal area for remediation. The contaminated soil is crushed, screened, and the soil moisture content is adjusted. The large particle components exceeding 30mm are used as slag and washed with high-pressure water flow. The particles with a diameter less than 30mm enter the thermal desorption system for disposal. The boiling point of the characteristic pollutant benzo(a)pyrene on the site is 475℃. The thermal desorption operation temperature is set at 500-570℃ and the heating time is 20-30min. The soil effect after remediation meets the site remediation goals.

[0056] The high-temperature exhaust gas discharged during the thermal desorption treatment process is first sprayed in the exhaust gas spray tower for treatment. The exhaust gas after spraying treatment enters the condenser for condensation and is separated into gas and liquid through the gas-liquid separator. The liquid and spray liquid produced by condensation enter the wastewater treatment system for treatment. The exhaust gas after gas-liquid separation is further treated by activated carbon adsorption. After the treatment is completed, it is tested. According to the monitoring results, the exhaust gas after treatment meets the secondary emission standards in the "Comprehensive Emission Standards of Air Pollutants" (GB16297-1996).

[0057] 3) Wastewater treatment

[0058] (1) The groundwater collected during the excavation process enters the integrated water treatment equipment for repair.

[0059] (2) During the thermal desorption process, the condensate generated from the wastewater from slag washing and the exhaust gas treatment is collected and then sent to the integrated water treatment equipment for repair.

[0060] The collected contaminated groundwater enters the integrated water treatment equipment for treatment, and a flocculation sedimentation tank and an oxidation tank are set up in the integrated water treatment equipment. The contaminated groundwater is pumped to the flocculation sedimentation tank, and alkali (0.5‰ sodium hydroxide), coagulant and flocculant (1‰PAC / 0.2‰PAM) are added for coagulation and sedimentation, and the sediment and suspended particles in the wastewater are combined into larger flocs, which are finally precipitated. Then the mud and water are separated through the inclined plate sedimentation tank, and the supernatant is discharged into the oxidation tank. The pH of the wastewater is adjusted in the oxidation tank, and the oxidant 1‰-5‰ hydrogen peroxide and the catalyst 0.5‰-2‰ ferrous sulfate (Fenton advanced oxidation) are added to oxidize and decompose the organic pollutants in the wastewater, and finally mineralize them into inorganic substances such as CO2 and H2O. The supernatant is filtered through a sand filter and an activated carbon tank. The sand filter removes suspended matter and impurities in the water. The activated carbon deeply purifies the water. After filtration, it enters the support pool to be accepted for testing. The test results meet the third-level standard of the "Comprehensive Sewage Discharge Standard" (GB8978-1996) and the C-level standard of the "Water Quality Standard for Sewage Discharge into Urban Sewers" (GB / T31962-2015), and are discharged into the pipe.

[0061] Step 3: Determine the repair effect

[0062] After the contaminated groundwater collected by excavation and the wastewater generated by the thermal desorption treatment process are repaired, sampling and testing are carried out in batches to ensure that all wastewater is repaired and meets the management and discharge standards. According to the test results, the wastewater of this project has achieved the repair target.

[0063] The soil after thermal desorption treatment was sampled and tested, and the detected pollutants were pollutants exceeding the standard for groundwater. The test results showed that the detection concentration of benzo(a)pyrene in the soil after repair was less than the detection limit of 0.1 mg / kg, which was far below the remediation target value of 1.5 mg / kg. The soil after thermal desorption treatment met the remediation target value, the pollutant removal rate was close to 100%, and the treatment effect was good.

[0064] During the construction process, the groundwater was monitored once a month through 5 monitoring wells around the repair area, and the results were all up to standard, indicating that the contaminated groundwater did not spread during the construction period. After the groundwater and aquifer medium soil were cleaned, the groundwater inside the foundation pit was monitored through 3 monitoring wells at the bottom of the foundation pit, and the results were all up to standard, indicating that the contaminated groundwater met the repair requirements.

[0065] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0066] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling and removing pollution sources in groundwater organic pollution sites, characterized in that: The groundwater pollution sources are controlled by constructing water-stop curtains, and then removed through excavation + ex situ disposal methods.

2. A method for controlling and removing pollution sources in groundwater organic contaminated sites according to claim 1, characterized in that: The following steps are involved: (1) Control of groundwater pollution sources 11) Review of pollution scope Before the construction of the water-stop curtain, a monitoring well shall be built at the boundary of the groundwater remediation area and samples shall be taken for testing. Based on the test results of the groundwater, the scope of groundwater contamination shall be reviewed; 12) Water-stop curtain construction After the boundaries of the groundwater pollution area are determined, a water-stop curtain is constructed according to the ground conditions to control the groundwater pollution source; (2) Elimination of groundwater pollution sources 21) Excavation in groundwater contaminated areas Excavate the designated area, collect contaminated groundwater during the excavation process and send it to the integrated treatment equipment for repair. The excavated aquifer medium soil is subjected to ex situ thermal desorption treatment. After the excavation is completed, the excavation effect of the foundation pit is inspected and accepted; 22) Thermal desorption of soil in aquifer media The soil from the aquifer medium in the contaminated groundwater area is transported to the thermal desorption treatment area for disposal. The contaminated soil is pre-treated, and large particles larger than 30 mm are screened out as slag, which is cleaned with high-pressure water flow; particles with a diameter less than 30 mm enter the thermal desorption system for disposal, and the high-temperature exhaust gas discharged during the thermal desorption treatment process is treated and monitored; 23) Wastewater treatment The contaminated groundwater collected during the excavation process and the wastewater generated during the thermal desorption treatment process are transported to the wastewater treatment facility and treated using a combined process of coagulation sedimentation → chemical oxidation → quartz sand filtration → activated carbon adsorption. After the treatment meets the standards, it is discharged into the pipeline; (3) Determination of repair effect After the contaminated groundwater collected through excavation and the wastewater generated during the thermal desorption treatment process are repaired, sampling and testing shall be carried out in batches to ensure that all the wastewater has been repaired and qualified; Take samples of the soil after thermal desorption treatment and test the pollutants to find out whether the pollutants are above the standard for groundwater, so as to ensure that the soil after thermal desorption treatment meets the requirements; During the construction process, the groundwater around the repair area is monitored once a month through monitoring wells to ensure that the groundwater has not spread. After the groundwater and aquifer medium soil are cleaned, the groundwater inside the foundation pit is tested through monitoring wells to ensure that the groundwater removal target is achieved.

3. A method for controlling and removing pollution sources in groundwater organic contaminated sites according to claim 2, characterized in that: The excavation described in step 21) is to excavate the designated area using a basin excavation method, that is, to excavate from the center of the foundation pit to the surrounding areas to ensure that groundwater flows to the center of the foundation pit during the construction process.

4. A method for controlling and removing pollution sources in groundwater organic contaminated sites according to claim 2, characterized in that: The pretreatment in step 22) includes: crushing, screening and adjusting the soil moisture content.

5. A method for controlling and removing pollution sources in groundwater organic contaminated sites according to claim 2, characterized in that: The operating temperature of the thermal desorption treatment in step 22) is 500-570°C, and the heating time is 20-30 minutes, so that the adsorbed and residual pollutants in the soil medium are heated into a gaseous form to be separated from the soil particles.

6. A method for controlling and removing pollution sources in groundwater organic contaminated sites according to claim 5, characterized in that: The high-temperature exhaust gas discharged in the thermal desorption treatment in step 22) is first sprayed through a tail gas spray tower, and the tail gas after the spraying treatment enters a condenser for condensation and is separated into gas and liquid through a gas-liquid separator. The tail gas after the gas-liquid separation is treated by activated carbon adsorption, and the liquid collected after the gas-liquid separation enters a water treatment device for disposal.

7. A method for controlling and removing pollution sources in groundwater organic contaminated sites according to claim 2, characterized in that: The wastewater treatment in step 23) specifically includes: The collected wastewater enters the integrated water treatment equipment for treatment. The integrated water treatment equipment is equipped with a flocculation sedimentation tank and an oxidation tank. The wastewater is pumped to the flocculation sedimentation tank, and alkali, coagulant and flocculant are added for coagulation and sedimentation. The sediment and suspended particles in the wastewater are combined into larger flocs, which are finally precipitated out. The mud and water are separated by the inclined plate sedimentation tank, and the supernatant is discharged into the oxidation tank. Chemical oxidation reaction is carried out in the oxidation tank. The supernatant of the oxidation tank is filtered through a sand filter and an activated carbon tank. After filtration, it enters the support water pool to be accepted for testing. If the test meets the standards, it will be discharged into the pipe.

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