VOCs waste gas treatment thermal oxidation furnace

Abstract

This invention discloses a VOCs waste gas treatment thermal oxidation furnace, relating to the field of VOCs waste gas treatment technology. It includes a gas supply module, a gas supply container, a thermal oxidation furnace body, and an exhaust container. The gas supply container has a first inlet and a first outlet. The first inlet of the gas supply container is connected to the gas supply port of the gas supply module, and the first outlet of the gas supply container is connected to the gas inlet of the thermal oxidation furnace body. The exhaust container has a second inlet and a second outlet. The exhaust container adopts a thermally conductive container shell and is located inside the gas supply container. The second inlet of the exhaust container is connected to the gas outlet of the thermal oxidation furnace body, and the second outlet of the exhaust container extends out of the gas supply container through a discharge pipe. Only the exhaust container needs to be heated, resulting in faster temperature rise. Only a heat-conducting plate needs to be selected as the thermally conductive container shell, greatly reducing the maintenance required for the equipment. The VOCs waste gas and hot gas are isolated from each other, making it easier to ensure the environmental protection of the discharged gas.

Description

Technical Field

[0001] This invention relates to the field of VOCs waste gas treatment technology, specifically to a VOCs waste gas treatment thermal oxidation furnace. Background Technology

[0002] Coating or printing equipment generates VOCs waste gas during use. If VOCs waste gas is directly discharged into the environment, it will cause serious pollution. Therefore, VOCs waste gas needs to be treated before being discharged.

[0003] The most common treatment method is RTO (thermal oxidation), which heats VOCs waste gas to its ignition point (usually 720℃) to burn and oxidize it into gases that meet emission standards.

[0004] Traditional RTO (Regenerative Thermal Oxidation) equipment is primarily a two-chamber RTO, as exemplified by the Chinese utility model patent (patent number 202020283464.9) entitled "An RTO Regenerative Incinerator." This furnace contains an interconnected combustion chamber and two regenerator chambers, equipped with multiple control valves to regulate the opening and closing of the regenerators. The hot gas generated by combustion heats the ceramic regenerators in each chamber under the control of these valves. VOCs (volatile organic compounds) are guided through these regenerator chambers to the combustion chamber, maximizing heat exchange between the VOCs and the high-temperature ceramic regenerators. This facilitates combustion and oxidation of the VOCs upon entering the combustion chamber, effectively reducing the energy consumption of active heating catalysis. Three-chamber RTOs, an extension of the two-chamber design, exist, operating on a similar principle. However, this type of RTO requires more control valves and has a higher failure rate.

[0005] To address this, industry professionals have designed RTO (Regenerative Thermal Oxidizer) devices that utilize rotating switching of regenerative ceramics. A typical example is the high-efficiency rotating switching RTO waste gas treatment device described in patent number "202120747448.5". This device features a waste gas inlet channel connected to the combustion decomposition zone and a hot gas outlet channel. A rotating motor sequentially switches between different regenerative ceramics in the waste gas inlet and outlet channels. After being heated in the hot gas outlet channel, the regenerative ceramic can switch to the waste gas inlet channel to heat VOCs waste gas. Once the temperature of the regenerative ceramic drops, it switches back to the hot gas outlet channel. Switching typically only requires controlling the rotation of the motor. However, this rotational switching can easily create dead zones, sometimes allowing VOCs waste gas to bypass the combustion decomposition zone and directly reach the hot gas outlet channel, reducing the controllability of exhaust gas quality.

[0006] When the aforementioned rotary switching RTO exhaust gas treatment device is started, multiple heat storage ceramics need to be preheated to the corresponding temperature, which requires a considerable amount of heating time.

[0007] The two-chamber RTO equipment, three-chamber RTO equipment, and rotary switching RTO exhaust gas treatment device mentioned above all use heat storage ceramics for heat storage and exchange. The pores of the heat storage ceramics are easily blocked, and the heat storage ceramics need to be replaced regularly, or the regular cleaning method proposed in Chinese utility model "Cylindrical RTO Furnace Drainage Device and Cylindrical RTO Furnace Body" with patent number 202122578056.3 can be used. Usually, it needs to be treated twice a month. Summary of the Invention

[0008] To overcome the shortcomings mentioned above, the present invention aims to provide a technical solution that can solve the above problems.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a VOCs waste gas treatment thermal oxidation furnace, comprising a gas supply module, a gas supply container, a thermal oxidation furnace body, and an exhaust container. The gas supply container has a first inlet and a first outlet. The first inlet of the gas supply container is connected to the gas supply port of the gas supply module, and the first outlet of the gas supply container is connected to the gas inlet of the thermal oxidation furnace body. The exhaust container has a second inlet and a second outlet. The exhaust container adopts a thermally conductive container shell. The exhaust container is located inside the gas supply container. The second inlet of the exhaust container is connected to the gas outlet of the thermal oxidation furnace body, and the second outlet of the exhaust container extends out of the gas supply container through a discharge pipe. The gas supply module is used to supply VOCs waste gas into the gas supply container and then into the thermal oxidation furnace body. After combustion and oxidation, the VOCs waste gas is discharged through the exhaust container. The VOCs waste gas exchanges heat with the hot gas in the exhaust container through the thermally conductive container shell.

[0010] As a further aspect of the present invention: the thermal oxidation furnace body adopts a heat-conducting furnace body shell, and the thermal oxidation furnace body is located inside the gas supply container.

[0011] As a further aspect of the present invention: the exhaust container includes a heat distribution chamber and a heat exchange tube, the heat distribution chamber having a hot gas outlet, a hot gas distribution control outlet, and a hot gas inlet for communicating with the gas outlet of the thermal oxidation furnace body; the gas inlet of the heat exchange tube is connected to the hot gas outlet, and the gas outlet of the heat exchange tube is connected to the exhaust pipe.

[0012] As a further aspect of the present invention: the hot gas distribution control outlet extends out of the gas delivery container through a distribution control pipe, and a hot gas volume control component is provided on the distribution control pipe; the hot gas volume control component is used to control the amount of hot gas discharged from the heat distribution chamber through the distribution control pipe.

[0013] As a further aspect of the present invention: the hot gas volume control component includes a first induced draft fan disposed on the distribution control pipe, the first induced draft fan being used to draw out the hot gas inside the distribution control pipe; the hot gas volume control component also includes a temperature control pipe connected to the distribution control pipe, the end of the temperature control pipe away from the distribution control pipe being located outside the gas delivery container, the temperature control pipe being provided with a control valve, the control valve being used to control the opening degree of the temperature control pipe; wherein, the connection position of the temperature control pipe on the distribution control pipe is located between the hot gas distribution control outlet and the induced draft position of the first induced draft fan.

[0014] As a further aspect of the present invention: the gas delivery container is provided with a partition assembly that divides the internal space of the gas delivery container into a first gas delivery chamber and a second gas delivery chamber; wherein, there is a channel between the first gas delivery chamber and the second gas delivery chamber, the first inlet is provided on the first gas delivery chamber, the first outlet is provided on the second gas delivery chamber, the thermal oxidation furnace body is provided in the second gas delivery chamber, and the heat exchange tube is provided in the first gas delivery chamber.

[0015] As a further aspect of the present invention: the control valve is an electrically controlled control valve, and the hot gas volume control component further includes a controller and a temperature detection unit; the temperature detection unit is used to detect the temperature of the hot gas in the heat exchange tube or the temperature of the hot gas in the heat distribution room or the temperature of the hot gas in the distribution control tube, and the controller receives the temperature signal from the temperature detection unit and controls the opening and closing of the electrically controlled control valve accordingly.

[0016] As a further aspect of the present invention: the air delivery module includes an air delivery pipe, an air delivery fan, and a switching valve; the air delivery pipe has a fresh air inlet, a VOCs exhaust gas inlet, and an air delivery outlet connected to the first inlet; the air delivery fan is used to deliver gas from the air delivery outlet and the first inlet into the air delivery container, and the switching valve is used to switch and control the opening and closing of the fresh air inlet and the VOCs exhaust gas inlet.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: During the process of sending VOCs waste gas into the thermal oxidation furnace, the VOCs waste gas and the hot gas discharged from the exhaust container exchange heat through the heat-conducting container shell, thereby heating the VOCs waste gas, making it easier for it to be combusted and oxidized after entering the thermal oxidation furnace. It only needs to heat the exhaust container, and the temperature rises faster.

[0018] Using the above heat exchange method, only plates with good thermal conductivity need to be selected as the shell of the heat-conducting container. This avoids the problem of blocked heat-conducting pores in traditional heat storage ceramics, greatly reducing the maintenance required for the equipment.

[0019] During the process of VOCs waste gas entering the thermal oxidation furnace and during the process of hot gas being discharged from the thermal oxidation furnace, the VOCs waste gas and hot gas are isolated from each other, which makes it easier to ensure the environmental protection of the gas discharge and avoids the problem caused by the traditional use of rotary RTO: VOCs waste gas sometimes reaches the discharge channel directly without combustion and decomposition, resulting in reduced controllability of exhaust quality.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a structural framework diagram of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention.

[0023] The markings in the attached diagram are explained as follows: Gas supply module-1, gas supply container-2, thermal oxidation furnace body-3, exhaust container-4, Air supply pipe-11, air supply fan-12, switching valve-13 Fresh air inlet - 101a, VOC exhaust gas inlet - 101b, air outlet - 102. First inlet - 201, First outlet - 202, Baffle assembly - 203, First air supply chamber - 204, Second air supply chamber - 205 Inlet -301, Outlet -302 Discharge pipe-403, heat distribution chamber-404, heat exchange pipe-405, distribution control pipe-406, first induced draft fan-407, temperature control pipe-408, control valve-409. Hot gas outlet -4041, hot gas distribution control outlet -4042, hot gas inlet -4043. Inlet pipe -4051, outlet pipe -4052. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Please see Figure 1-2 A VOCs waste gas treatment thermal oxidation furnace includes an air supply module 1, an air supply container 2, a thermal oxidation furnace body 3, and an exhaust container 4.

[0026] The gas supply container 2 has a first inlet 201 and a first outlet 202. The first inlet 201 of the gas supply container 2 is connected to the gas supply port of the gas supply module 1, and the first outlet 202 of the gas supply container 2 is connected to the gas inlet 301 of the thermal oxidation furnace body 3.

[0027] The exhaust container 4 has a second inlet and a second outlet. The exhaust container 4 adopts a thermally conductive container shell. The exhaust container 4 is located inside the gas supply container 2. The second inlet of the exhaust container 4 is connected to the gas outlet 302 of the thermal oxidation furnace body 3. The second outlet of the exhaust container 4 passes through the gas supply container 2 through a discharge pipe 403.

[0028] The gas supply module 1 is used to send VOCs waste gas into the gas supply container 2, and then into the thermal oxidation furnace body 3. After combustion and oxidation, the VOCs waste gas is discharged through the exhaust container 4. The VOCs waste gas in the gas supply container 2 and the hot gas in the exhaust container 4 exchange heat through the heat-conducting container shell.

[0029] The thermal oxidation furnace body 3 serves as a combustion furnace and has its own gas burner. The gas burner can be used to heat the exhaust container 4 by burning gas during the heat cycle, or to ignite the VOCs exhaust gas by auxiliary ignition, and then heat the exhaust container 4.

[0030] During the process of VOCs waste gas being fed into the thermal oxidation furnace 3, the VOCs waste gas and the hot gas discharged from the exhaust container 4 exchange heat through the heat-conducting container shell, thereby heating the VOCs waste gas and making it easier for it to be combusted and oxidized after entering the thermal oxidation furnace 3. It only needs to heat the exhaust container 4, resulting in faster temperature rise.

[0031] Using the above heat exchange method, only plates with good thermal conductivity need to be selected as the shell of the heat-conducting container. This avoids the problem of pore blockage caused by the traditional use of heat storage ceramics, and greatly reduces the maintenance required for the equipment.

[0032] During the process of VOCs waste gas entering the thermal oxidation furnace 3 and during the process of hot gas being discharged from the thermal oxidation furnace 3, the VOCs waste gas and hot gas are isolated from each other. The flow direction of VOCs waste gas is unidirectional. VOCs waste gas must pass through the thermal oxidation furnace 3, which makes it easier to ensure the environmental protection of the gas discharge and avoids the problem caused by the traditional use of rotary RTO: VOCs waste gas sometimes reaches the discharge channel directly without combustion and decomposition, resulting in reduced controllability of exhaust quality.

[0033] Preferably, the air supply module 1 includes an air supply pipe 11, an air supply fan 12, and a switching valve 13; the air supply pipe 11 has a fresh air inlet 101a, a VOCs exhaust gas inlet 101b, and an air supply outlet 102 connected to the first inlet 201; the air supply fan 12 is used to supply gas from the air supply outlet 102 and the first inlet 201 into the air supply container 2, and the switching valve 13 is used to switch and control the opening and closing of the fresh air inlet 101a and the VOCs exhaust gas inlet 101b.

[0034] When the equipment starts operating, the VOCs exhaust gas inlet can be closed and the fresh air inlet opened by controlling the switching valve. Under the action of the air supply fan, a large amount of fresh air can enter the thermal oxidation furnace, removing the impurities left after the previous operation and supplying enough oxygen to the thermal oxidation furnace. Then, the VOCs exhaust gas inlet can be opened. Alternatively, the exhaust container can be heated by gas combustion first, and then the VOCs exhaust gas inlet can be opened.

[0035] Of course, when there is insufficient oxygen during the combustion of VOCs exhaust gas, the fresh air inlet can be opened by switching the valve to supply appropriate oxygen.

[0036] In this embodiment of the invention, the thermal oxidation furnace body 3 adopts a heat-conducting furnace shell, and the thermal oxidation furnace body 3 is located inside the gas supply container 2.

[0037] Preferably, the exhaust container 4 includes a heat distribution chamber 404 and a heat exchange tube 405. The heat distribution chamber 404 has a hot gas outlet 4041, a hot gas distribution control outlet 4042, and a hot gas inlet 4043 for communication with the outlet 302 of the thermal oxidation furnace body 3. The inlet 4051 of the heat exchange tube 405 is connected to the hot gas outlet 4041, and the outlet 4052 of the heat exchange tube 405 is connected to the exhaust pipe 403. The heat exchange tube 405 extends out of the gas supply container 2 through the exhaust pipe 403.

[0038] The hot gas distribution control outlet 4042 extends out of the gas delivery container 2 through a distribution control pipe 406, and a hot gas volume control component is provided on the distribution control pipe 406; the hot gas volume control component is used to control the amount of hot gas discharged from the heat distribution chamber 404 through the distribution control pipe 406.

[0039] The hot gas volume control component includes a first induced draft fan 407 mounted on the distribution control pipe 406, which is used to draw out the hot gas inside the distribution control pipe 406. The hot gas volume control component also includes a temperature control pipe 408 connected to the distribution control pipe 406. The end of the temperature control pipe 408 away from the distribution control pipe 406 is located outside the gas delivery container 2. A control valve 409 is mounted on the temperature control pipe 408, which is used to control the opening degree of the temperature control pipe 408. The connection position of the temperature control pipe 408 on the distribution control pipe 406 is located between the hot gas distribution control outlet 4042 and the induced draft position of the first induced draft fan 407.

[0040] Preferably, the gas supply container 2 is provided with a partition assembly 203 that divides the internal space of the gas supply container 2 into a first gas supply chamber 204 and a second gas supply chamber 205; wherein, there is a channel between the first gas supply chamber 204 and the second gas supply chamber 205, the first inlet 201 is provided on the first gas supply chamber 204, the first outlet 202 is provided on the second gas supply chamber 205, the thermal oxidation furnace body 3 is provided in the second gas supply chamber 205, and the heat exchange tube 405 is provided in the first gas supply chamber.

[0041] After VOCs waste gas enters the gas delivery container, it first exchanges heat with the hot gas in the heat exchange tube in the first gas delivery chamber, preheating the VOCs waste gas to the first temperature range. Then, the VOCs waste gas in the first temperature range enters the second gas delivery chamber and exchanges heat with the hot gas inside the thermal oxidation furnace through the heat-conducting furnace shell, preheating the VOCs waste gas to the second temperature range, which is close to the ignition point of the VOCs waste gas.

[0042] Taking the ignition point of VOCs waste gas as 720 degrees and the temperature of the hot gas in the thermal oxidation furnace after combustion as 720-900 degrees, the first temperature range is room temperature to 650 degrees, and the second temperature range is 650-700 degrees.

[0043] Preferably, the heat distribution chamber 404 adopts a thermally conductive shell. The heat distribution chamber 404 is located inside the second air supply chamber 205. The VOCs exhaust gas first passes through the shell of the heat distribution chamber 404 inside the second air supply chamber, and then passes through the shell of the thermal oxidation furnace body 3.

[0044] It is worth noting that, since the hot gas inside the thermal oxidizing furnace travels from the thermal oxidizing furnace body 3 to the heat distribution chamber 404, and then to the heat exchange tube 405, the temperature relationship of the hot gas at each location is as follows: the temperature of the hot gas inside the thermal oxidizing furnace body > the temperature of the hot gas inside the heat distribution chamber > the temperature of the hot gas inside the heat exchange tube.

[0045] Therefore, the VOCs exhaust gas first undergoes heat exchange through the outer shell of the heat distribution chamber, which can better ensure that the VOCs exhaust gas entering the thermal oxidation furnace is in the second temperature range.

[0046] Under the induced draft of the first induced draft fan 407, when the control valve 409 controls the temperature control tube 408 to close, the distribution control tube 406 is subjected to the maximum induced draft negative pressure of the first induced draft fan 407, causing a large amount of hot air in the heat distribution chamber 404 to be discharged from the hot air distribution control outlet 4042, thus reducing the amount of hot air discharged from the hot air outlet to the heat exchange tube 405.

[0047] When the control valve 409 controls the temperature control tube 408 to open, the distribution control tube 406 is reduced by the induced draft negative pressure of the first induced draft fan 407, and the hot air in the heat distribution chamber 404 is reduced and discharged from the hot air distribution control outlet 4042, so that the amount of hot air discharged from the hot air outlet to the heat exchange tube 405 is relatively large.

[0048] By controlling the amount of hot gas discharged to the heat exchange tube 405 per unit time, the preheating temperature of VOCs waste gas in the first gas delivery chamber 204 can be controlled, making the preheating temperature easier to control.

[0049] Furthermore, the control valve is an electrically controlled valve, and the hot gas volume control component also includes a controller and a temperature detection unit; the temperature detection unit is used to detect the temperature of the hot gas in the heat exchange tube, or to detect the temperature of the hot gas in the heat distribution room, or to detect the temperature of the hot gas in the distribution control tube, and the controller receives the temperature signal from the temperature detection unit and controls the opening and closing of the electrically controlled valve accordingly.

[0050] In addition to being fully open and fully closed, electrically controlled valves can also control other opening degrees.

[0051] When used to detect the temperature of hot gas inside the heat exchanger tubes: when the detected temperature is higher than the preset value, the electrically controlled valve closes (or reduces its opening), allowing more hot gas to escape from the hot gas distribution control outlet; when the detected temperature is lower than the preset value, the electrically controlled valve opens (or increases its opening), allowing more hot gas to escape from the hot gas outlet. The preset value can be, for example, any value between 450°C and 600°C, and the detection position is close to the outlet. Electrical control is more precise and faster.

[0052] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A VOCs off-gas treatment thermal oxidizer, characterized by, Includes gas supply module, gas supply container, thermal oxidation furnace body and exhaust container; The gas supply container has a first inlet and a first outlet. The first inlet of the gas supply container is connected to the gas supply port of the gas supply module, and the first outlet of the gas supply container is connected to the gas inlet of the thermal oxidation furnace body. The exhaust container has a second inlet and a second outlet. The exhaust container adopts a thermally conductive container shell. The exhaust container is located inside the gas supply container. The second inlet of the exhaust container is connected to the gas outlet of the thermal oxidation furnace body. The second outlet of the exhaust container extends out of the gas supply container through a discharge pipe. The gas delivery module is used to deliver VOCs waste gas into the gas delivery container and then into the thermal oxidation furnace. After combustion and oxidation, the VOCs waste gas is discharged through the exhaust container. The VOCs waste gas in the gas delivery container and the hot gas in the exhaust container exchange heat through the heat-conducting container shell. The thermal oxidation furnace body adopts a heat-conducting furnace body shell, and the thermal oxidation furnace body is located inside the gas supply container; The exhaust container includes a heat distribution chamber and heat exchange tubes; The heat distribution chamber has a hot gas outlet, a hot gas distribution control outlet, and a hot gas inlet for communicating with the gas outlet of the thermal oxidation furnace body. The inlet of the heat exchange tube is connected to the outlet of the hot air, and the outlet of the heat exchange tube is connected to the outlet pipe. The gas delivery container is provided with a partition assembly that divides the internal space of the gas delivery container into a first gas delivery chamber and a second gas delivery chamber. The first gas supply chamber and the second gas supply chamber are connected by a channel. The first inlet is located in the first gas supply chamber, the first outlet is located in the second gas supply chamber, the thermal oxidation furnace body is located in the second gas supply chamber, and the heat exchange tube is located in the first gas supply chamber.

2. The VOCs exhaust treatment thermal oxidation furnace according to claim 1, characterized in that, The hot gas distribution control outlet extends out of the gas delivery container through a distribution control pipe, and a hot gas volume control component is provided on the distribution control pipe. The hot air volume control component is used to control the amount of hot air discharged from the distribution control pipe in the heat distribution chamber.

3. The VOCs exhaust treatment thermal oxidation furnace according to claim 2, characterized in that, The hot gas volume control component includes a first induced draft fan installed on the distribution control pipe, which is used to draw out the hot gas in the distribution control pipe; The hot gas volume control component also includes a temperature control tube connected to the distribution control tube. The end of the temperature control tube away from the distribution control tube is located outside the gas delivery container. A control valve is provided on the temperature control tube, and the control valve is used to control the opening degree of the temperature control tube. The temperature control tube is connected to the distribution control tube at a position between the hot gas distribution control outlet and the induced draft position of the first induced draft fan.

4. The VOCs exhaust treatment thermal oxidation furnace according to claim 3, characterized in that, The control valve is an electrically controlled control valve, and the hot gas volume control component also includes a controller and a temperature detection unit; The temperature detection unit is used to detect the temperature of the hot air in the heat exchange tube, or the temperature of the hot air in the heat distribution room, or the temperature of the hot air in the distribution control tube. The controller receives the temperature signal from the temperature detection unit and controls the opening and closing of the electrically controlled valve accordingly.

5. The VOCs off-gas treatment thermal oxidizer according to any one of claims 1-4, characterized in that, The air supply module includes an air supply pipe, an air supply fan, and a switching valve; The air supply pipe has a fresh air inlet, a VOCs exhaust gas inlet, and an air supply outlet connected to the first inlet; The air supply fan is used to send gas from the air supply outlet and the first inlet into the air supply container, and the switching valve is used to switch the opening and closing of the fresh air inlet and the VOCs exhaust gas inlet.

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