A system and method for combined treatment of coking wastewater and volatile organic gases

Abstract

The invention relates to a system and method for the combined treatment of coking wastewater and volatile organic gas, comprising a pre-physicochemical device, an O / H / H / O biological treatment device, a post-physicochemical device and a volatile organic gas purification device, wherein multiple emission sources of volatile organic gases in a coking wastewater treatment system are collected in a distributed manner, and low-flow high-concentration volatile organic gases are negatively pressure absorbed by an ejector, and the gases are fully mixed with unsaturated activated carbon sludge of the post-physicochemical device and introduced into the volatile organic gas purification device, and fluidization is used to promote the continuous and dynamic adsorption process of the unsaturated activated carbon sludge on the volatile organic gas, thereby ensuring the efficient purification of the volatile organic gas and meeting the emission standards. This process not only realizes the effective control and emission standards of the volatile organic gas, but also maximizes the use of the adsorption capacity of the activated carbon sludge, and realizes the recycling of the unabsorbed saturated activated carbon.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater and waste gas treatment, and in particular to a system and method for combined treatment of coking wastewater and volatile organic gases. Background Art

[0002] Volatile organic compounds (VOCs) refer to organic compounds with a saturated vapor pressure greater than 70.91 Pa at room temperature and a boiling point less than 260°C at normal pressure, or any organic solid or liquid that can volatilize at room temperature and pressure. VOCs mainly include 8 categories: alkanes, halogenated hydrocarbons, aromatic hydrocarbons, olefins, esters, ketones and other organic compounds (chlorine-containing organic matter, nitrogen-containing organic matter, sulfur-containing organic matter). Excessive emission of VOCs will directly or indirectly cause environmental pollution (smelly substances, O3 precursors, PM 2.5 Precursors, etc.) and harm to human health (poisoning, carcinogenic, teratogenic, mutagenic, etc.). Taking the coking wastewater generated by coal chemical enterprises as an example, it is estimated that the annual VOCs emission of the coking wastewater treatment industry is about 402t, mainly benzene series, halogenated hydrocarbons and chlorobenzene compounds. The volatility of VOCs causes a variety of components in the wastewater to transfer from the liquid phase to the gas phase. During the treatment of coking wastewater, the fate of raw water VOCs (taking benzene series as an example) is mainly volatilization, sludge adsorption, biodegradation, and discharge with effluent. The proportions of each pathway are 48.50%, 20.74%, 19.58%, and 11.18%, respectively. The relevant health risk assessment found that the carcinogenic risk associated with gaseous VOCs is 3.0×10 -5 ~7.8×10 -4 (much higher than the 1×10 -6 ), the non-cancer risk HR of benzene is 3.008 (exceeding the risk threshold of 1). Excessive VOCs emissions cause pungent odors to be present around coking wastewater treatment plants all year round, which not only causes serious environmental pollution, but also harms the health of operators, causes corrosion to various production equipment, and has safety hazards of combustion and explosion when not properly handled. Therefore, it is urgent to seek efficient VOCs control and treatment technologies.

[0003] Existing VOCs treatment facilities are mainly aimed at treating unorganized waste gas in the plant environment of sewage treatment plants, but due to the complexity of multi-source emissions in the plant area, it is difficult to achieve comprehensive and effective collection and treatment. Especially when using the O / H / H / O process to treat coking wastewater, although activated carbon is used to adsorb low-concentration pollutants, unadsorbed saturated activated carbon is often discharged with the sludge, resulting in a waste of resources. Therefore, how to develop a coking wastewater and volatile organic gas joint treatment system that aims to simultaneously treat wastewater and centrally collect various VOCs emission sources, while using unadsorbed saturated activated carbon to remove VOCs for recycling, is an urgent problem that needs to be solved. Summary of the invention

[0004] In view of the technical problems existing in the prior art, the first object of the present invention is to provide a system for the combined treatment of coking wastewater and volatile organic gases, including a pre-physicochemical device, an O / H / H / O biological treatment device, a post-physicochemical device and a volatile organic gas purification device, to collect multiple volatile organic gas emission sources in the coking wastewater treatment system in a distributed manner, to absorb small-flow high-concentration volatile organic gases (VOCs) under negative pressure through an ejector, to fully mix them with the unsaturated activated carbon sludge of the post-physicochemical device and to introduce them into the volatile organic gas purification device, to utilize fluidization to promote the continuous and dynamic adsorption process of the unsaturated activated carbon sludge on the volatile organic gases, thereby ensuring the efficient purification of the volatile organic gases and meeting the emission standards. This process not only realizes the effective control and emission standards of volatile organic gases, but also maximizes the utilization of the adsorption capacity of the activated carbon sludge, thereby realizing the recycling of the unabsorbed saturated activated carbon.

[0005] The second object of the present invention is to provide a method for the combined treatment of coking wastewater and volatile organic gases, which solves the systemic problems of difficult collection of volatile organic gases from multiple sources, complex treatment operations, difficult resource utilization of waste gas, low efficiency and high cost.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A system for the combined treatment of coking wastewater and volatile organic gases, comprising: a pre-physicalization device for receiving and removing harmful components in the coking wastewater; an O / H / H / O biological treatment device, wherein the O / H / H / O biological treatment device is located downstream of the pre-physicalization device and degrades and transforms the organic pollutants in the coking wastewater from the pre-physicalization device; and a post-physicalization device, wherein the post-physicalization device is located downstream of the O / H / H / O biological treatment device and degrades and transforms the organic pollutants in the coking wastewater from the O / H / H / O biological treatment device. The water is mixed with the activated carbon, and the supernatant and the sludge containing unsaturated activated carbon are separated for deep treatment and emission in compliance with the emission standards; a volatile organic gas purification device, the volatile organic gas purification device comprising: a shell, a guide tube is arranged in the shell to divide the space in the shell into a descending chamber and an ascending chamber arranged inside and outside and fluidically connected; the top of the ascending chamber is provided with a mud inlet pipe for receiving the unsaturated activated carbon sludge and a discharge port for discharging the purified gas, the upper part of the ascending chamber is provided with a mud outlet, and the mud outlet is used to discharge the purified volatile organic gas into the descending chamber and the ascending chamber; The activated carbon sludge of organic gas is returned to the pre-physicalization device and the O / H / H / O biological treatment device, and the bottom of the riser is provided with an aeration pipe to promote the flow of unsaturated activated carbon sludge between the downcomer and the riser; the top of the downcomer is formed with a first connecting port for receiving the sludge in the riser and the bottom is formed with a second connecting port for discharging the sludge, wherein the sludge inlet pipe extends into the downcomer through the first connecting port; the side of the riser is also provided with an output pipe and an input pipe arranged up and down, and the output pipe and the The input pipes extend horizontally from the sides of the rising chamber to the interior of the descending chamber, and the output pipe and the input pipe are fluidly connected through a conveying pipeline outside the rising chamber. An ejector is arranged on the conveying pipeline, and the ejector is configured to receive volatile organic gases generated from the pre-chemical treatment device and the O / H / H / O biological treatment device, so as to mix the volatile organic gases with the unsaturated activated carbon sludge and allow the volatile organic gases to enter the descending chamber from the input pipe, and remove the volatile organic gases by utilizing the adsorption capacity of the unsaturated activated carbon sludge.

[0008] Furthermore, the ejector includes a cylinder, an intake chamber, a mixing chamber and a diffusion chamber arranged in series in the cylinder, the intake chamber is used to receive the unsaturated activated carbon sludge and the volatile organic gas, the mixing chamber is used to mix the unsaturated activated carbon sludge and the volatile organic gas, and the diffusion chamber is used to diffuse the mixed medium and transport it to the input pipe.

[0009] Furthermore, a circulating water pump is also arranged on the delivery pipeline between the ejector and the input pipe.

[0010] Furthermore, the output pipe extends horizontally from the side of the ascending chamber and bends downward in the descending chamber, and the input pipe extends horizontally from the side of the ascending chamber and bends upward in the descending chamber.

[0011] Furthermore, a conical guide plate is provided at the bottom of the rising chamber.

[0012] Furthermore, a hollow plate is also arranged on the first connecting port, and the hollow plate has a ring-shaped part, a central column and a plurality of support rods, one end of each of the plurality of support rods is fixed on the central column, and the other end thereof is fixed on the inner wall of the ring-shaped part, and a through hole for receiving sludge is formed between two adjacent support rods, and the central column is used to receive the sludge inlet pipe.

[0013] Furthermore, the outer wall of the guide tube has a plurality of reinforcing ribs, and the reinforcing ribs extend horizontally from the outer wall of the guide tube and are fixed to the inner wall of the shell.

[0014] Furthermore, the medium introduced into the aeration pipe is air or ozone.

[0015] Furthermore, a volatile organic gas concentration detector is provided at the discharge port.

[0016] According to the method for the combined treatment system of coking wastewater and volatile organic gases, the method comprises the following steps:

[0017] The coking wastewater is supplied to the pre-physicochemical unit, and ferrous salt and polyacrylamide are added to precipitate and complex the high concentration of sulfide, cyanide and thiocyanate in the raw water to reduce their biological toxicity;

[0018] Introducing the coking wastewater into an O / H / H / O biological treatment device to degrade and transform organic pollutants in the coking wastewater;

[0019] The coking wastewater is introduced into the post-physical and chemical device, and polyferric iron, activated carbon, liquid alkali and polyacrylamide are added respectively to further reduce the suspended solids and color in the biological effluent, separate the supernatant and the sludge containing unsaturated activated carbon, and the supernatant meets the discharge standards;

[0020] The unsaturated activated carbon sludge is introduced into the volatile organic gas purification device through the sludge inlet pipe, and the volatile organic gas generated from the pre-physicochemical device and the O / H / H / O biological treatment device is mixed with the unsaturated activated carbon sludge by an ejector and enters the descending chamber from the input pipe, and the volatile organic gas is removed by using the adsorption capacity of the unsaturated activated carbon sludge;

[0021] Allowing the unsaturated activated carbon sludge to flow in the downcomer and the upcomer through an aeration pipe;

[0022] The purified volatile organic gas is discharged from the discharge port, and at the same time, the activated carbon sludge from which the volatile organic gas has been purified flows back to the pre-physical treatment device and the O / H / H / O biological treatment device through the sludge outlet, thereby realizing the recycling of the activated carbon.

[0023] The present invention has the following advantages:

[0024] 1. A system for the combined treatment of coking wastewater and volatile organic gas of the present invention comprises a pre-physicochemical device, an O / H / H / O biological treatment device, a post-physicochemical device and a volatile organic gas purification device, and collects multiple volatile organic gas emission sources in the coking wastewater treatment system in a distributed manner, and negatively absorbs the volatile organic gas with a small flow rate and a high concentration by an ejector, and fully mixes it with the unsaturated activated carbon sludge of the post-physicochemical device and enters the volatile organic gas purification device, and completes the gas-liquid-solid three-phase mixing and reaction by the power of the ejector and aeration, and at the same time, the internal circulation in the driving device is strengthened to enhance the countercurrent mass transfer effect, and the unsaturated activated carbon sludge is promoted to continuously and dynamically adsorb the volatile organic gas by the fluidization, so as to enhance the mass transfer efficiency, thereby ensuring the efficient purification of the volatile organic gas and meeting the emission standards. This process not only realizes the effective control and emission standards of the volatile organic gas, but also maximizes the use of the adsorption capacity of the activated carbon sludge by recycling the unabsorbed saturated activated carbon, and truly realizes the synchronous treatment of wastewater and waste gas.

[0025] 2. The volatile organic gas purification device of the present invention can enhance the step-by-step adsorption saturation of the gas-solid mass transfer adsorption activated carbon adsorbent in the liquid phase, realize the linkage and synchronous removal of gas-liquid pollutants in sludge and organic volatile gases, improve the utilization efficiency of activated carbon, and reduce the operating costs of the VOCs treatment process. Among them, the adsorption effect and adsorption capacity are enhanced by more than 15%, and it can be used in conjunction with the coking wastewater treatment system to reduce the operating costs by more than 30%.

[0026] 3. The volatile organic gas purification device of the present invention is equipped with a conveying pipeline to realize the external circulation of unsaturated activated carbon sludge, and by configuring an ejector on the conveying pipeline, negative pressure water phase absorption of distributed multi-point source gas is realized. Through flexible regulation of pumping and gas-liquid flow rate, it can be applied to different VOCs emission scenarios, and the collected VOCs are transferred to the rising chamber and the descending chamber for efficient purification.

[0027] 4. The present invention utilizes VOCs-loaded activated carbon as a resource, and uses it as a biological carrier, a denitrification carbon source, an enhancer for sludge disposal, a catalyst, and coke preparation in the biological treatment process of coking wastewater, thereby solving the problem of the resource fate of activated carbon and greatly improving the economic benefits.

[0028] 5. The aeration pipe of the present invention can also be used to introduce ozone, and through the efficient and flexible use of ozone, a multi-selective technical platform is provided for VOCs control in different fields and scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the flow structure of the system for combined treatment of coking wastewater and volatile organic gases of the present invention.

[0030] Figure 2 It is a schematic structural diagram of the volatile organic gas purification device of the present invention.

[0031] Figure 3 It is a schematic structural diagram of the ejector of the present invention.

[0032] Figure 4 It is a structural schematic diagram of the hollow plate of the present invention.

[0033] Figure 5 It is a process flow chart of the method for combined treatment of coking wastewater and volatile organic gases of the present invention.

[0034] Among them, 1 is a pre-physicochemical device, 2 is an O / H / H / O biological treatment device, 3 is a post-physicochemical device, 4 is a volatile organic gas purification device, 401 is a shell, 4a is a descending chamber, 4b is an ascending chamber, 401a is a mud inlet pipe, 401b is a discharge port, 401c is a mud outlet, 401d is an aeration pipe, 401e is a conical guide plate, 401f is a reinforcing rib, 401g is a rain cover, 401h is an inspection port, 401i is a third connecting port, 402 is a guide tube, 402a is a first The connecting port is 402b, 402c is a hollow plate, 402c1 is a ring-shaped member, 402c2 is a central column, 402c3 is a support rod, 403 is an output pipe, 404 is an input pipe, 405 is a delivery pipeline, 406 is an ejector, 406a is a cylinder, 406b is a suction chamber, 406c is a mixing chamber, 406d is a diffusion chamber, 407 is a circulating water pump, 5 is a volatile organic gas delivery pipeline, 6 is an unsaturated activated carbon sludge delivery pipeline, and 7 is an activated carbon sludge delivery pipeline. DETAILED DESCRIPTION

[0035] The following description is essentially only exemplary and is not intended to limit the present invention, its application or use. It will be further understood that the term "include" and / or "comprising" specifies the existence of the features, wholes, steps, operations, elements and / or parts described when used in this specification, but does not exclude the existence of one or more other features, wholes, steps, operations, elements, parts and / or its groups or add one or more other features, wholes, steps, operations, elements, parts and / or its groups. As used in this article, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be understood that when an element, component and / or part is referred to as "connected to another element, component and / or part", it can be directly connected to another element, component and / or part, or there can be an intermediate element. It will be understood that although the terms "first", "second" and the like can be used to describe various elements, components and / or parts in this article, these elements, components and / or parts should not be limited by these terms. These terms are only used to distinguish an element, component or part from another element, component or part. Therefore, the first element, part or part discussed below can be referred to as the second element, part or part without departing from the teaching of the present invention. Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meanings as those commonly understood by those of ordinary skill in the field to which the present invention belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the relevant field and / or the context of this specification, and will not be interpreted in an idealized or overly formal sense, unless clearly defined in this article.

[0036] It should be understood that, in order to clearly show the contents therein, the drawings herein are not drawn to scale, and the same or similar reference numerals indicate the same or similar components or parts. In addition, it should be understood that any embodiments described in this application and the technical features included therein can be combined with each other.

[0037] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0038] like Figure 1-4 As shown, a system for the combined treatment of coking wastewater and volatile organic gas comprises: a pre-physicalization device 1, an O / H / H / O biological treatment device 2, a post-physicalization device 3 and a volatile organic gas purification device 4.

[0039] like Figure 1As shown, there is a pre-physicalization device 1 for receiving and removing harmful components in coking wastewater; an O / H / H / O biological treatment device 2, which is located downstream of the pre-physicalization device 1 and degrades and transforms organic pollutants in the coking wastewater from the pre-physicalization device 1; and a post-physicalization device 3, which is located downstream of the O / H / H / O biological treatment device 2 and mixes the coking wastewater from the O / H / H / O biological treatment device 2 with activated carbon to separate the supernatant and the sludge containing unsaturated activated carbon for deep treatment and discharge up to standard, wherein the unsaturated activated carbon sludge is liquid sludge. Among them, the pre-physicalization device 1, the O / H / H / O biological treatment device 2 and the post-physicalization device 3 are defined as a coking wastewater treatment system. Ferrous salts and polyacrylamide (PAM) are added to the pre-physicalization device 1 to precipitate and complex the high-concentration sulfide (S 2- ), cyanide (CN - ) and thiocyanate (SCN - ) to reduce its biological toxicity. A water collecting and regulating tank is also provided between the pre-physicochemical device 1 and the O / H / H / O biological treatment device 2. The water collecting and regulating tank balances the water quality and quantity of the effluent from the pre-physicochemical device 1 and other wastewater, and then pumps them to the O / H / H / O biological treatment device 2; the O / H / H / O biological treatment device 2 mainly includes an aerobic unit (O1), a hydrolysis denitrification unit (H1), a hydrolysis denitrification unit (H2) and an aerobic unit (O2). The aerobic unit (O1) controls the DO concentration by adjusting the aeration intensity. The ammonification, nitrite and nitrification stages are reached respectively, and most of the organic matter is removed at the same time. Phosphorus salts and liquid alkali are added to ensure the nutrients required for microbial growth and to supplement the alkalinity consumed by nitrification. The hydrolysis denitrification unit (H1) and the hydrolysis denitrification unit (H2) are anaerobic hydrolysis denitrification units, which can further degrade the difficult-to-degrade organic matter anaerobically, and can also regulate the combination / coupling of various denitrification modes such as anaerobic ammonia oxidation / autotrophic denitrification / heterotrophic denitrification to achieve efficient removal of total nitrogen; the aerobic unit (O2) is used for further thorough carbon removal and nitrification. The post-physical and chemical device 3 adds polyiron, activated carbon, liquid alkali and PAM respectively to further reduce the suspended matter and color in the biological effluent, wherein the post-physical and chemical device 3 produces unsaturated activated carbon sludge, which is transported to the volatile organic gas purification device 4 through the unsaturated activated carbon sludge transport pipeline 6.

[0040] like Figure 1 and Figure 2As shown, the volatile organic gas purification device 4 includes: a shell 401, a guide tube 402 is arranged in the shell 401 to divide the space in the shell 401 into a descending chamber 4a and an ascending chamber 4b arranged inside and outside and fluidly connected; the top of the ascending chamber 4b is provided with a mud inlet pipe 401a for receiving unsaturated activated carbon sludge and a discharge port 401b for discharging purified gas, wherein the discharge port 401b can also control the pressure inside the shell 401, the upper part of the ascending chamber 4b is provided with a mud outlet 401c, and the mud outlet 401c is used to return the activated carbon sludge that has purified the volatile organic gas to the pre-physicalization device 1 and the O / H / H / O biological treatment device 2, wherein the activated carbon sludge is automatically discharged from the mud outlet 401c to control the liquid level in the shell 401, and the bottom of the ascending chamber 4b is provided with an aeration pipe 401d to promote the flow of unsaturated activated carbon sludge between the descending chamber 4a and the ascending chamber 4b. The top of the downcomer 4a is formed with a first communication port 402a for receiving the sludge from the upcomer 4b and the bottom is formed with a second communication port 402b for discharging the sludge, wherein the sludge inlet pipe 401a extends into the downcomer 4a through the first communication port 402a. The side of the upcomer 4b is also provided with an output pipe 403 and an input pipe 404 arranged up and down, both of which extend horizontally from the side of the upcomer 4b to the inside of the downcomer 4a, and the output pipe 403 and the input pipe 404 are fluidically connected through a delivery pipeline 405 outside the upcomer 4b, and an ejector 406 is provided on the delivery pipeline 405, and the ejector 406 is configured to receive the volatile organic gas generated from the pre-physicalization device 1 and the O / H / H / O biological treatment device 2, so as to mix the volatile organic gas with the unsaturated activated carbon sludge and enter the downcomer 4a from the input pipe 404, and remove the volatile organic gas by utilizing the adsorption capacity of the unsaturated activated carbon sludge. Among them, the shell 401 and the guide tube 402 are both hollow cylindrical cylinders 406a, and the diameter of the shell 401 is larger than the diameter of the guide tube 402. The aeration tube 401d at the bottom drives the unsaturated activated carbon sludge to flow, forming an orderly internal circulation flow in which the sludge rises in the rising chamber 4b and descends in the descending chamber 4a. Among them, the exhaust gas discharge pipe is configured at the discharge port 401b, and the outlet end of the exhaust gas discharge pipe is configured with a rain cover 401g. In addition, a third connecting port 401i is configured on the lower side wall of the rising chamber 4b, and the third connecting port 401i is used to connect other volatile organic gas purification devices 4 in series to enhance the synchronous treatment capacity of wastewater and waste gas.

[0041] Unsaturated activated carbon sludge is produced by the post-physical device 3, flows through the volatile organic gas purification device 4, and then flows back to the pre-physical device 1 and the O / H / H / O biological treatment device 2, realizing the step-by-step adsorption saturation of pollutants from low concentration to high concentration. Since coking wastewater contains a large amount of volatile organic matter, during the treatment process, the pre-physical device 1, the regulating tank and the accident tank will release a large amount of volatile organic matter, causing multi-point source air pollution and stench in the surrounding environment. It is very necessary to collect and treat volatile organic matter. Since a variety of agents are added during the treatment of coking wastewater, the linkage treatment technology of volatile organic gas combined with unsaturated activated carbon sludge becomes the preferred choice for efficient and economical treatment means. Among them, the adsorption saturated activated carbon sludge is discharged from the mud outlet 401c and pumped to the O / H / H / O biological treatment device 2 through the activated carbon sludge conveying pipeline 7 as a biological carrier and a carbon source for denitrification, realizing the recycling of adsorbents and self-purification of endogenous substances in wastewater.

[0042] In an embodiment not shown, a volatile organic gas concentration detector is provided at the discharge port 401b, which is used to detect whether the volatile organic gas is meeting the emission standards. The feed end of the mud inlet pipe 401a can be provided with a reagent dosing device. When it is detected that the index of the volatile organic gas does not meet the emission standard, the reagent can be transported to the downcomer 4a through the reagent dosing device to further process the volatile organic gas so that it meets the emission standards.

[0043] like Figure 1 and Figure 3As shown, the ejector 406 includes a cylinder 406a, a suction chamber 406b, a mixing chamber 406c and a diffusion chamber 406d arranged in series in the cylinder 406a, the suction chamber 406b is used to receive unsaturated activated carbon sludge and volatile organic gas, the mixing chamber 406c is used to mix unsaturated activated carbon sludge and volatile organic gas, and the diffusion chamber 406d is used to diffuse and transport the mixed medium to the input pipe 404. A circulating water pump 407 is also configured on the delivery pipeline 405 between the ejector 406 and the input pipe 404. Among them, the circulation pipeline of the unsaturated activated carbon sludge is formed by the output pipe 403, the input pipe 404 and the externally configured delivery pipeline 405, and the external circulation of the medium is realized by the pumping force of the circulating water pump 407. The delivery pipeline 405 is configured with an ejector 406, and the ejector 406 is a venturi ejector 406, and the venturi ejector 406 is connected to the volatile organic gas delivery pipeline 5. The venturi ejector 406 is one of the key components of the system. It utilizes the venturi effect, which is manifested in that when the restricted fluid passes through the reduced flow section, the flow velocity of the fluid increases, and the flow velocity is inversely proportional to the flow section. According to Bernoulli's principle, the increase in flow velocity is accompanied by a decrease in fluid pressure, which in turn forms a negative pressure in the mixing chamber 406c. The negative pressure draws gas into the mixing chamber 406c, and the volatile organic gas is mixed with the sludge entering the inlet of the venturi ejector 406. Finally, the water-gas mixture is ejected through the outlet of the diffusion chamber 406d of the venturi ejector 406. The venturi ejector 406 increases the contact area between the volatile organic gas and the sludge through the jet effect, accelerating the gas-liquid absorption process. There may be multiple ejectors 406, which are arranged in parallel on the delivery pipeline 405, and each ejector 406 corresponds to each device in the coking wastewater treatment system. For example, two ejectors 406 are arranged in parallel, one ejector 406 is connected to the volatile organic gas delivery pipeline 5 of the pre-physicalization device 1, and the other ejector 406 is connected to the volatile organic gas delivery pipeline 5 of the O / H / H / O biological treatment device 2. The ejector 406 may also be set to one, and the volatile organic gas delivery pipeline 5 collects the volatile organic gases of multiple devices through parallel pipelines, and then centrally delivers them to the ejector 406.

[0044] like Figure 1 and Figure 2As shown, the output pipe 403 extends horizontally from the side of the ascending chamber 4b and bends downward in the descending chamber 4a, and the input pipe 404 extends horizontally from the side of the ascending chamber 4b and bends upward in the descending chamber 4a. Among them, the output pipe 403 is located above the input pipe 404, and the mixture of unsaturated activated carbon sludge and volatile organic gas bends upward from the input pipe 404 into the descending chamber 4a, so that it is opposite to the fluid flow direction in the descending chamber 4a, strengthens the countercurrent mass transfer, enhances the processing capacity and load, and improves the processing efficiency. This countercurrent method greatly enhances the gas-liquid-solid contact time and mass transfer efficiency. The output pipe 403 extends horizontally and bends downward in the descending chamber 4a, and the output direction is the same as the sludge flow direction, preventing excessive sludge from being discharged from the output pipe 403 and affecting the flow of sludge. Preferably, the output pipe 403 extends horizontally from the side of the ascending chamber 4b and bends downward at an angle of 90°, and the input pipe 404 extends horizontally from the side of the ascending chamber 4b and bends upward at an angle of 90°.

[0045] like Figure 1 and Figure 2 As shown, the bottom of the rising chamber 4b is also provided with a conical guide plate 401e. The conical guide plate 401e is located in the middle of the bottom of the rising chamber 4b, which plays a role in strengthening the fluidization of the sludge. This not only effectively improves the flow stability of the fluid inside the device, but also enhances the efficiency of aeration and stirring, thereby avoiding the deposition of sludge and activated carbon and improving the treatment efficiency.

[0046] like Figure 1 and Figure 4 As shown, the first communication port 402a is also provided with a hollow plate 402c, which has an annular member 402c1, a central column 402c2 and a plurality of supporting rods 402c3, one end of each of the plurality of supporting rods 402c3 is fixed on the central column 402c2, and the other end thereof is fixed on the inner wall of the annular member 402c1, and a through hole for receiving sludge is formed between two adjacent supporting rods 402c3, and the central column 402c2 is used to receive the mud inlet pipe 401a. The hollow plate 402c is used for structural support to ensure the physical stability of the guide tube 402, and the central column 402c2 can fix the mud inlet pipe 401a, so as to ensure that the mud inlet pipe 401a will not deviate or shake during operation, so that it can be inserted into the interior of the descending chamber 4a. In an embodiment not shown, the hollow plate 402c is a funnel-shaped structure, and the hollow plate 402c has an opening. The mud inlet pipe 401a is inserted into the descending chamber 4a through the opening, and a certain gap is left between the mud inlet pipe 401a and the opening, so that the fluid in the ascending chamber 4b is collected to the bottom through the funnel-shaped hollow plate 402c, and then enters the descending chamber 4a from the gap, so as to accelerate the fluidization of the fluid and improve the processing efficiency.

[0047] like Figure 1 and Figure 2As shown, the outer wall of the guide tube 402 has a plurality of reinforcing ribs 401f, which extend horizontally from the outer wall of the guide tube 402 and are fixed to the inner wall of the housing 401. The reinforcing ribs 401f are fixed to provide structural support to ensure the physical stability of the guide tube 402.

[0048] like Figure 1 and Figure 2 As shown, the medium introduced into the aeration pipe 401d is air or ozone. Ozone is used as an oxidant, and by controlling the residence time of the reaction, pollutants are completely oxidized, absorbed and adsorbed, so that the exhaust gas is purified to meet the standards before being discharged into the air.

[0049] like Figure 5 As shown, according to the method for the combined treatment system of coking wastewater and volatile organic gas, the method comprises the following steps:

[0050] S1, pre-physical chemical treatment: the coking wastewater is provided to the pre-physical chemical treatment device 1, and ferrous salt and polyacrylamide are added to precipitate and complex the high concentration of sulfide, cyanide and thiocyanate in the raw water to reduce their biological toxicity;

[0051] S2, O / H / H / O biological treatment: introducing the coking wastewater into the O / H / H / O biological treatment device 2 to degrade and transform the organic pollutants in the coking wastewater;

[0052] S3, post-physicalization: the coking wastewater is introduced into the post-physicalization device 3, and polyferric acid, activated carbon, liquid alkali and polyacrylamide are added respectively to further reduce the suspended solids and chromaticity in the biological effluent, and the supernatant and the sludge containing unsaturated activated carbon are separated, and the supernatant meets the discharge standards;

[0053] S4, jet mixing: the unsaturated activated carbon sludge is introduced into the volatile organic gas purification device 4 through the sludge inlet pipe 401a, and the volatile organic gas generated from the pre-physical treatment device 1 and the O / H / H / O biological treatment device 2 is mixed with the unsaturated activated carbon sludge by the ejector 406 and enters the descending chamber 4a from the input pipe 404, and the volatile organic gas is removed by the adsorption capacity of the unsaturated activated carbon sludge;

[0054] S5. Fluidized bed adsorption of VOCs: the unsaturated activated carbon sludge is made to flow in the downcomer 4a and the upcomer 4b through the aeration pipe 401d; the purified volatile organic gas is discharged from the discharge port 401b, and at the same time, the activated carbon sludge from which the volatile organic gas has been purified flows back to the pre-physicalization device 1 and the O / H / H / O biological treatment device 2 through the mud outlet 401c, so as to realize the recycling of the activated carbon.

[0055] Among them, activated carbon powder is added to the post-physicochemical device 3 to further reduce the concentration of effluent pollutants, and at the same time reduce the operating costs of deep treatment processes such as microfiltration-ultrafiltration-nanofiltration-reverse osmosis; the sediment mud-water mixture containing unadsorbed saturated activated carbon in the post-physicochemical device 3 is transported to the volatile organic gas purification device 4 through the unadsorbed saturated activated carbon sludge conveying pipeline 7, and is used as an adsorbent for treating VOCs; the mud-water mixture containing activated carbon after secondary adsorption in the volatile organic gas purification device 4 is transported to the pre-physicochemical device 1 through the activated carbon sludge conveying pipeline 7 to further adsorb high-concentration pollutants in the raw water, and is transported to the O / H / H / O biological treatment device 2 as a biological carrier and carbon source for denitrification; ozone aeration can be introduced into the aeration pipe 401d to regenerate the activated carbon in situ by ozone; the saturated activated carbon after step-by-step adsorption eventually returns to the sludge, and in the subsequent sludge filtration and pyrolysis process, the doped activated carbon can improve the treatment efficiency. The above method realizes the efficient and synchronous linkage of coking wastewater treatment and VOCs treatment process, enhances the economic value of activated carbon, and reduces the treatment cost of gas-liquid pollutants.

[0056] Example 1

[0057] Taking the coking wastewater treatment project as an example, a wastewater and waste gas combined treatment process of a pre-physical chemical device 1, an O / H / H / O biological treatment device 2, a post-physical chemical device 3 and a volatile organic gas purification device 4 is adopted. The unsaturated activated carbon sludge produced by the post-physical chemical device 3 is transported through the unsaturated activated carbon sludge conveying pipeline 6 and enters the downcomer 4a through the mud inlet pipe 401a. The volatile organic gas from the pre-physical chemical device 1 and the O / H / H / O biological treatment device 2 enters the ejector 406 through the volatile organic gas conveying pipeline 5. At the same time, the circulating water pump 4 07 The sludge in the descending chamber of the volatile organic gas purification device 4 is used as the circulating fluid of the ejector 406. The ejector 406 is a fluid machinery and mixed reaction equipment that uses the jet turbulence diffusion effect to transfer energy and mass. Through the nozzle-type suction chamber 406b, as the nozzle diameter continues to decrease, the fluid is ejected from the nozzle at a very high speed. When the high-speed airflow is ejected from the ejector 406, the faster airflow will drive the slower airflow to form a decompression area, causing the surrounding gas to move to the decompression area, which produces a certain negative pressure effect. After a large amount of volatile organic gas is sucked into the mixing chamber 406c, it is divided into a large number of tiny bubbles under the action of the water spray pressure and forms a mixture with the fluid. The gas-liquid mixture is discharged outward through the diffusion chamber 406d, its speed slows down, the pressure increases, and a strong jet flow is formed, which then becomes countless tiny bubbles with a large surface area, making it easier for the volatile organic gas to dissolve quickly in the fluid. Since the bubble diameter is small and the rising speed is slow, the time for the volatile organic gas to dissolve in the fluid is prolonged, and the fluid and the volatile organic gas are fully mixed and contacted. Generally, the more bubbles are generated by the diffusion of the gas per unit volume, the larger the gas-liquid contact interface is formed, and the higher the mass transfer efficiency between the volatile organic gas and the fluid is. The amount of bubbles generated by the diffusion of the ejector 406 directly affects the transfer efficiency of the volatile gas dissolving in water. After the water and gas are mixed, they enter the lower part of the descending chamber 4a through the input pipe 404, and the water and gas mixture follows the descending chamber 4a and the ascending chamber 4b for fluid movement. With the help of the adsorption of activated carbon, the volatile organic gas is effectively removed. The flow in the ejector 406 is a complex two-phase flow, and the gas is sucked and compressed by the liquid jet. According to the degree of mixing between the gas and liquid phases, the flow process in the ejector 406 can be divided into three sections: (I) relative movement section of the liquid jet and the gas; (II) droplet movement section; (III) foam flow movement section. In the second and third stages, the gas-liquid contact interface area is quite large, which strengthens the mass transfer between the two phases. The negative pressure effect generated in the ejector 406 is as follows:

[0058] Bernoulli equation:

[0059] Relationship between points 1 and 2 in the Venturi tube:

[0060] When the flow rate is constant, the relationship between the flow velocity and the flow cross section is:

[0061] flow:

[0062] Among them, the output pipe 403 of the volatile organic gas purification device 4 is set at a height of 1.5m from the liquid level in the descending chamber 4a, and the input pipe 404 is set at the lower part of the descending chamber 4a, so as to realize the process of gas-liquid countercurrent contact in the descending chamber 4a. Due to the surface resistance of the liquid to the gas, the residence time of the volatile organic gas is increased, and the gas-liquid mass transfer efficiency is greatly improved. The aeration pipe 401d is installed at the bottom of the ascending chamber 4b, and the density difference caused by aeration is used as the power source of fluid movement. The gas buoyancy and the interaction force between the gas, liquid and solid three phases are used to quickly complete the energy transfer, maintain the fluidization of the fluid inside the volatile organic gas purification device 4, and complete the efficient material transfer between the three phases.

[0063] The activated carbon in the volatile organic gas purification device 4 can adsorb up to 2000 mg / g of VOCs. VOCs transfer to the adsorbent surface through convection and diffusion, and diffuse into the adsorbent through the pores. The proportion of pores of micro, medium and large pore sizes of the adsorbent plays a key role in the adsorption equilibrium stage, among which the micropores only provide adsorption sites, while the medium and large pores will also enhance the diffusion of VOCs. Activated carbon is continuously added to the volatile organic gas purification device 4, and after saturation of adsorption, it is continuously discharged from the mud outlet 401c above the volatile organic gas purification device 4, which is in a dynamic process. The pure gas adsorbed on the top of the volatile organic gas purification device 4 is discharged from the exhaust pipe at high altitude (>15m). In this embodiment, the activated carbon adsorbent used comes from the activated carbon-containing bottom mud that is not saturated with adsorption in the post-physical and chemical device 3, with a volume of 1 to 3m 3 The unsaturated activated carbon sludge was continuously pumped into the volatile organic gas purification device 4 at a flow rate of / h. After stable operation, sampling and analysis were carried out for 5 consecutive days. The VOCs adsorption effect is shown in Table 1. It can be seen from the table that after the collected volatile organic gases were treated by the device, the indicators such as hydrogen sulfide, ammonia, styrene, trimethylamine and odor concentrations were reduced to below the "Emission Standards for Odor Pollutants" and met the emission standards.

[0064] Table 1

[0065]

[0066] Volatile organic gas purification device outlet sampling port

[0067]

[0068]

[0069] After the activated carbon is adsorbed by the volatile organic gas purification device 4, it overflows and is discharged from the mud outlet 401c and transferred to the pre-physical device 1 through the activated carbon sludge conveying pipeline 7 to further adsorb high-concentration pollutants in the raw water. Then, the pre-physical device 1 further adsorbs the saturated activated carbon sludge and pumps it to the O / H / H / O biological treatment device 2 as a microbial carrier. At the same time, the adsorbed VOCs components are used as a supplementary carbon source for denitrification. Biological activated carbon uses activated carbon as a carrier, and allows microorganisms to grow and reproduce on the surface of activated carbon under anaerobic, anoxic or aerobic conditions. The organic matter (VOCs) adsorbed in the activated carbon is used as nutrients, and the purpose of removing pollutants in the water is achieved through the synergistic effect of activated carbon adsorption and microbial decomposition. The essence of this technology is to use the characteristics of activated carbon with huge specific surface area, developed pore structure and excellent adsorption performance, so that the surface of activated carbon particles becomes a good culture medium for microorganisms, adsorbs microorganisms, and the rough concave parts on the surface of activated carbon also have the function of shielding the shear force of water flow to facilitate the growth and reproduction of microorganisms. In this way, activated carbon, as a carrier, enriches or artificially immobilizes microorganisms to build a biofilm, completing the synergistic treatment process of activated carbon adsorbing volatile organic compounds and microorganisms oxidizing and decomposing organic compounds. The role of the biofilm is to regenerate the activated carbon by biodegrading part of the organic matter adsorbed by the activated carbon through the process of obtaining nutrients and energy through oxidation and decomposition, thereby extending the service life of the activated carbon. The removal of VOCs attached to the activated carbon carrier is a multi-step process, in which pollutants diffuse from the gas phase to the liquid phase / biofilm, then to the cell surface of the microorganisms, and finally are biodegraded by microorganisms (mainly bacteria and fungi). When air passes through the packed bed, the volatile organic components adsorbed in the activated carbon are transferred from the airflow to the water in the biofilm. Once adsorbed in the biofilm layer or dissolved in the water layer around the biofilm, they can serve as food for microbial metabolism and as a source of carbon and energy to maintain the life and growth of the microorganisms. Volatile organic components can also be directly adsorbed on the surface of the packing and then transported to the microbial cells and degraded. Table 2 summarizes the typical pollutant concentrations in the O / H / H / O biological treatment device 2. It can be found that the combined use of activated carbon in the organic volatile gas and sewage treatment process can reduce 37% of the external carbon source without affecting the water quality indicators of the external discharge.

[0070] Table 2

[0071]

[0072] The commonly used high-efficiency adsorption-desorption-combustion VOCs treatment technology currently has an equipment investment of 2 to 3 million yuan (air volume 50,000m 3 / h), the operating cost is about 300,000 to 500,000 yuan / year, the main equipment life is 10 to 15 years, the RCO combustion technology reaction temperature is 300 to 500 ° C, and the VOCs removal efficiency is generally between 95% and 98%. It can be used in the treatment of large air volume, low concentration or unstable concentration of organic waste gas in the petroleum, chemical, electronics, machinery, coating and other industries. Compared with the above technologies, when this system uses activated carbon as an adsorbent to treat the same air volume, the equipment investment cost is 750,000 to 1.5 million yuan, the operating cost is 150,000 to 250,000 yuan / year, and the main equipment life is 15 to 20 years. The adsorbed VOCs are in-situ resourced and utilized without combustion, the reaction temperature is room temperature, and the VOCs removal efficiency exceeds 98%. It can be used for VOCs treatment in different industry scenarios, especially in the combined use of waste gas and wastewater, which produces huge economic benefits. In this embodiment, the method of combining the volatile organic gas purification device 4 with the O / H / H / O biological treatment device 2 fully utilizes the physical adsorption of activated carbon while fully utilizing the biodegradation effect of the microorganisms in the activated carbon on the adsorbed VOCs, thereby extending the service life of the activated carbon and reducing the sludge discharge and the dosage of the reagents in the whole process of coking wastewater treatment. In addition, the unsaturated activated carbon sludge produced by the post-physical chemical device 3 is returned to the volatile organic gas purification device 4 to fully realize the recycling and reuse of the adsorbent and reduce the treatment cost of the whole process. According to the three waste discharge rules of general coking wastewater treatment projects, the total amount of gaseous pollutants is less than 0.05% (taking polycyclic aromatic hydrocarbons as an example), and each 1m 3 Wastewater only requires less than 0.1 kg of activated carbon (activated carbon after water treatment), which does not constitute a problem of increasing the unit amount of activated carbon. Therefore, the use of activated carbon helps to dehydrate sludge and has a positive impact on water treatment processes or sludge, that is, a synergistic effect.

[0073] Example 2

[0074] The difference between this embodiment and embodiment 1 is that: when the activated carbon added by the post-physicalization device 3 cannot meet the VOCs treatment in the volatile organic gas purification device 4 or the VOCs adsorbed by the activated carbon cannot be utilized in situ, the partial or complete regeneration of the adsorbed saturated activated carbon will become a new VOCs treatment mode. At this time, the conveying medium of the aeration pipe 401d is changed from air to ozone (O3). Combined with the in-situ catalytic oxidation of O3, the strong oxidant ozone is used to decompose the volatile organic matter adsorbed on the activated carbon to achieve the regeneration of the activated carbon, which can extend the service life of the activated carbon and reduce the treatment cost. Activated carbon can be used as an adsorption carrier of ozone or as an efficient catalyst for ozone catalytic oxidation. In this embodiment, the saturated activated carbon is no longer or only partially transported to the O / H / H / O biological treatment device 2 as a microbial carrier and carbon source for use, but is regenerated in situ by ozone catalytic oxidation, and the VOCs component is mainly degraded by ozone oxidation.

[0075] The reaction mechanism of ozone catalysis of VOCs is as follows: the aerated ozone and the water vapor mixture sprayed by the ejector 406 are evenly mixed in the volatile organic gas purification device 4. With the help of activated carbon, ozone efficiently catalytically oxidizes and degrades VOCs on the activated carbon to form a catalytic oxidation composite module. The catalytic oxidation composite module is used to enhance the catalytic oxidation ability of ozone. After ozone (oxidation potential 2.07V) is adsorbed on the surface of activated carbon, it is decomposed by the catalyst in the aqueous solution to form strong oxidizing oxygen free radicals and hydroxyl free radicals. Due to its high reactivity and oxidizing properties, it can quickly oxidize VOCs gaseous pollutants such as benzene series that cannot be oxidized by O3 alone into non-toxic CO2 and H2O, and finally achieve complete elimination and utilization of ozone. The apparent activation energy of the ozone catalytic reaction is low, and the catalytic oxidation of VOCs can be achieved at a relatively low temperature. The product is mainly CO2, which is a good low-concentration gas pollutant purification technology.

[0076] The structure of the volatile organic gas purification device 4 is the same as that of Example 1, and realizes gas, liquid, and solid three-phase countercurrent mass transfer in the fluid rising chamber 4b, and simultaneously occurs activated carbon adsorption of VOCs, activated carbon adsorption of ozone, and ozone catalytic oxidation degradation of VOCs, which can realize activated carbon adsorption and in-situ regeneration. However, under room temperature conditions, due to incomplete catalytic decomposition, a small amount of aldehyde, acid, and ester intermediates are easily accumulated on the surface of the material, covering the active sites of the catalyst, resulting in a decrease in catalyst activity or even inactivation. Therefore, the regeneration and utilization capacity of activated carbon has a certain limit and needs to be discharged regularly. The addition and discharge of activated carbon are intermittent. When the temperature is 0.1 to 0.5 m 3 The unsaturated activated carbon precipitated sludge in the post-physicalization device 3 is continuously pumped to the volatile organic gas purification device 4 at a flow rate of / h. When the ozone dosage is 5-10kg / h, sampling and analysis are carried out for 5 consecutive days after stable operation. The VOCs adsorption effect is shown in Table 3. It can be seen from the table that after the collected exhaust gas is treated by the VOCs tower, the indicators such as hydrogen sulfide, ammonia, styrene, trimethylamine and odor concentration are reduced to below the "Emission Standards for Odor Pollutants" and meet the emission standards.

[0077] Table 3

[0078]

[0079]

[0080] Example 3

[0081] The difference between this embodiment and embodiment 2 is that the ozone addition point is changed from aeration pipe 401d to ejector 406, and ozone is added to suction chamber 406b, so that ozone, organic waste gas and wastewater are mixed in ejector 406, which prolongs the contact time between ozone and VOCs components and wastewater, makes their mixed mass transfer more complete, and enhances the treatment efficiency, while the internal structure and function of the reactor are the same as those of embodiment 1. 3 The post-physical and chemical activated carbon precipitated sludge is continuously pumped into the VOCs absorption tower at a flow rate of / h. When the ozone dosage is 5-10kg / h, sampling and analysis are carried out for 5 consecutive days after stable operation. The VOCs adsorption effect is shown in Table 4. It can be seen from the table that after the collected exhaust gas is treated by the VOCs tower, the indicators such as hydrogen sulfide, ammonia, styrene, trimethylamine and odor concentration are reduced to below the "Emission Standards for Odor Pollutants" and meet the emission standards. This embodiment has better treatment efficiency for typical pollutant indicators, but the operating cost is higher than that of activated carbon technology. Appropriate technical solutions can be adopted for different VOCs backgrounds and scenarios.

[0082] Table 4

[0083]

[0084]

[0085] In general, a system for the combined treatment of coking wastewater and volatile organic gases of the present invention comprises a pre-physicochemical device, an O / H / H / O biological treatment device, a post-physicochemical device and a volatile organic gas purification device, and a distributed collection of multiple volatile organic gas emission sources in the coking wastewater treatment system is performed, and a small flow rate and high concentration volatile organic gas is subjected to negative pressure absorption by an ejector, and the volatile organic gas is fully mixed with the unsaturated activated carbon sludge of the post-physicochemical device and enters the volatile organic gas purification device, and the gas-liquid-solid three-phase mixing and reaction are completed by the power of the ejector and aeration, and the internal circulation in the driving device is strengthened to enhance the countercurrent mass transfer effect, and the unsaturated activated carbon sludge is used to promote the continuous and dynamic adsorption process of the volatile organic gas by the unsaturated activated carbon sludge, so as to enhance the mass transfer efficiency, thereby ensuring the efficient purification of the volatile organic gas and the emission up to standard. This process not only realizes the effective control and emission up to standard of the volatile organic gas, but also maximizes the utilization of the adsorption capacity of the activated carbon sludge through the recycling of the unabsorbed saturated activated carbon, and truly realizes the synchronous treatment of wastewater and waste gas. The volatile organic gas purification device of the present invention can strengthen the step-by-step adsorption saturation of the gas-solid mass transfer adsorption activated carbon adsorbent in the liquid phase, realize the linkage and synchronous removal of gas-liquid pollutants in sludge and organic volatile gases, improve the use efficiency of activated carbon, and reduce the operating cost of the VOCs treatment process, wherein the adsorption effect and adsorption capacity are enhanced by more than 15%, and it can be used in conjunction with the coking wastewater treatment system to reduce the operating cost by more than 30%. The volatile organic gas purification device of the present invention is equipped with a delivery pipeline to realize the external circulation of unsaturated activated carbon sludge, and by configuring an ejector on the delivery pipeline, the negative pressure water phase absorption of distributed multi-point source gas is realized. Through pumping and flexible regulation of gas-liquid flow rate, it can be applied to different VOCs escape scenarios, and the collected VOCs are transferred to the ascending chamber and the descending chamber for efficient purification. The present invention utilizes the activated carbon loaded with VOCs as a resource, and is used as a biological carrier, a denitrification carbon source, an enhancer for sludge disposal, a catalyst, and coke preparation in the biological treatment process of coking wastewater, etc., which solves the problem of resource conversion of activated carbon and greatly improves the economic benefits. The aeration pipe of the present invention can also introduce ozone, and through the efficient and flexible use of ozone, a multi-selective technical platform is provided for VOCs control in different fields and scenarios.

[0086] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A system for the combined treatment of coking wastewater and volatile organic gases, characterized in that: include: Pre-physicalization device for receiving and removing harmful components from coking wastewater; An O / H / H / O biological treatment device, wherein the O / H / H / O biological treatment device is located downstream of the pre-physicalization device and degrades and transforms organic pollutants in the coking wastewater from the pre-physicalization device; A post-physicalization device, which is located downstream of the O / H / H / O biological treatment device, and in which the coking wastewater from the O / H / H / O biological treatment device is mixed with activated carbon, and a supernatant and sludge containing unsaturated activated carbon are separated for deep treatment and discharge up to standard; A volatile organic gas purification device, the volatile organic gas purification device comprising: A shell, wherein a guide tube is disposed in the shell to divide the space in the shell into a descending chamber and an ascending chamber which are arranged inside and outside and are fluidically connected; The top of the riser chamber is provided with a mud inlet pipe for receiving the unsaturated activated carbon sludge and a discharge port for discharging the purified gas, the upper part of the riser chamber is provided with a mud outlet, the mud outlet is used to return the activated carbon sludge purified of volatile organic gas to the pre-physicalization device and the O / H / H / O biological treatment device, and the bottom of the riser chamber is provided with an aeration pipe to promote the flow of the unsaturated activated carbon sludge between the descender chamber and the riser chamber; The top of the descending chamber is formed with a first communication port for receiving the sludge in the ascending chamber and the bottom thereof is formed with a second communication port for discharging the sludge, wherein the sludge inlet pipe extends into the descending chamber through the first communication port; The side of the rising chamber is also provided with an output pipe and an input pipe arranged up and down, the output pipe and the input pipe both extend horizontally from the side of the rising chamber to the inside of the descending chamber, the output pipe and the input pipe are fluidically connected through a delivery pipeline outside the rising chamber, the delivery pipeline is provided with an ejector, the ejector is configured to receive volatile organic gas generated from the pre-physicalization device and the O / H / H / O biological treatment device, so as to mix the volatile organic gas with the unsaturated activated carbon sludge and allow the volatile organic gas to enter the descending chamber from the input pipe, and remove the volatile organic gas by utilizing the adsorption capacity of the unsaturated activated carbon sludge; The ejector comprises a cylinder, a suction chamber, a mixing chamber and a diffusion chamber arranged in series in the cylinder, the suction chamber is used to receive the unsaturated activated carbon sludge and the volatile organic gas, the mixing chamber is used to mix the unsaturated activated carbon sludge and the volatile organic gas, and the diffusion chamber is used to diffuse the mixed medium and transport it to the input pipe; The output pipe extends horizontally from the side of the ascending chamber and bends downward in the descending chamber, and the input pipe extends horizontally from the side of the ascending chamber and bends upward in the descending chamber; The first connecting port is also provided with a hollow plate, which has a ring-shaped part, a central column and a plurality of support rods, one end of each of the plurality of support rods is fixed on the central column, and the other end thereof is fixed on the inner wall of the ring-shaped part, and a through hole for receiving sludge is formed between two adjacent support rods, and the central column is used to receive the sludge inlet pipe.

2. A system for the combined treatment of coking wastewater and volatile organic gases according to claim 1, characterized in that: A circulating water pump is also arranged on the delivery pipeline between the ejector and the input pipe.

3. A system for the combined treatment of coking wastewater and volatile organic gases according to claim 1, characterized in that: The bottom of the rising chamber is also provided with a conical guide plate.

4. A system for the combined treatment of coking wastewater and volatile organic gases according to claim 1, characterized in that: The outer wall of the guide tube has a plurality of reinforcing ribs, and the reinforcing ribs extend horizontally from the outer wall of the guide tube and are fixed to the inner wall of the shell.

5. A system for the combined treatment of coking wastewater and volatile organic gases according to claim 1, characterized in that: The medium introduced into the aeration pipe is air or ozone.

6. A system for the combined treatment of coking wastewater and volatile organic gases according to claim 1, characterized in that: The discharge port is provided with a volatile organic gas concentration detector.

7. A method using the system for combined treatment of coking wastewater and volatile organic gases according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: The coking wastewater is supplied to the pre-physicochemical unit, and ferrous salt and polyacrylamide are added to precipitate and complex the high concentration of sulfide, cyanide and thiocyanate in the raw water to reduce its biological toxicity; Introducing the coking wastewater into an O / H / H / O biological treatment device to degrade and transform organic pollutants in the coking wastewater; The coking wastewater is introduced into the post-physical and chemical device, and polyferric iron, activated carbon, liquid alkali and polyacrylamide are added respectively to further reduce the suspended solids and color in the biological effluent, separate the supernatant and the sludge containing unsaturated activated carbon, and the supernatant meets the discharge standards; The unsaturated activated carbon sludge is introduced into the volatile organic gas purification device through the sludge inlet pipe, and the volatile organic gas generated from the pre-physicochemical device and the O / H / H / O biological treatment device is mixed with the unsaturated activated carbon sludge by an ejector and enters the descending chamber from the input pipe, and the volatile organic gas is removed by using the adsorption capacity of the unsaturated activated carbon sludge; Allowing the unsaturated activated carbon sludge to flow in the downcomer and the upcomer through an aeration pipe; The purified volatile organic gas is discharged from the discharge port, and at the same time, the activated carbon sludge from which the volatile organic gas has been purified flows back to the pre-physical treatment device and the O / H / H / O biological treatment device through the sludge outlet, thereby realizing the recycling of the activated carbon.

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