Direct combustion furnace, organic waste gas treatment system and treatment method

Abstract

The invention discloses a direct-fired furnace and an organic waste gas treatment system and method. A first heat exchanger and a second heat exchanger are arranged in a heat exchange area in the direct-fired furnace, and a combustor is arranged in a combustion area; high-concentration organic waste gas to be treated is sucked into a first gas inlet of the direct combustion furnace, and low-concentration standard gas formed after treatment is sucked into a second gas inlet of the direct combustion furnace; a heating inlet of the first heat exchanger is connected with a first gas inlet, a heating outlet is communicated with a combustion area inlet, a heating inlet of the second heat exchanger is connected with a second gas inlet, a heating outlet is connected with a second gas outlet of the direct combustion furnace, and the second gas outlet is used for introducing heating gas to heat and desorb adsorbed volatile organic compounds; a cooling inlet end of the first heat exchanger is communicated with a combustion area outlet, and a cooling outlet of the first heat exchanger is connected with a cooling inlet of the second heat exchanger which is communicated with a first gas outlet of the direct combustion furnace. According to the technical scheme, adsorption cold air heating and high-concentration organic waste gas preheating can be achieved at the same time, the occupied space is saved, and cost and energy consumption are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of organic waste gas treatment, and particularly relates to a direct combustion furnace, an organic waste gas treatment system and a treatment method. Background Art

[0002] A direct combustion incinerator (referred to as "direct combustion furnace" for short) treats volatile organic compounds (VOCs) through the principle of high-temperature oxidation. The interior of a conventional furnace type is a cavity structure, and various heat recovery devices such as heat exchangers and boilers can be configured outside the furnace according to actual needs. The direct combustion incinerator can be widely used for waste gases in complex working conditions such as high concentration and containing particulate matter, and can effectively recover the heat energy released during the oxidation process. The direct combustion incinerator has a variety of shapes and can be designed according to the characteristics of the on-site space, such as a square cavity, a cylindrical cavity, and can also be made into a vertical furnace, a horizontal furnace, an L-shaped furnace, etc.

[0003] During the chip production and processing process in the semiconductor industry, the tail gas often contains organosilicon compounds. Through the combustion method, the treatment efficiency of organic waste gas can reach more than 99.9% after high-temperature oxidation. The concentration of VOCs in the tail gas is relatively low, and a concentrator wheel needs to be configured for concentration in a conventional design. After the concentrator wheel adsorbs VOCs, the organic matter will be adsorbed on the surface of the zeolite of the concentrator wheel. The zeolite still needs to be heated so that the VOCs on the surface will be desorbed again. Therefore, the conventional design is to increase an electric heater or a burner for afterburning for desorption, but this will lead to an increase in energy consumption.

[0004] After the concentrated high-concentration waste gas enters the direct combustion furnace for incineration, an external heat exchanger generally needs to be configured at the rear end of the direct combustion furnace for preheating recovery. Since a large amount of silicon dioxide is generated after the high-temperature oxidation of organosilicon in the tail gas, it is easy to block the heat exchanger unit, so the system needs to be shut down regularly for ash cleaning. After heat exchange by the heat exchanger, there is still a large amount of silicon dioxide in the flue gas. The normal process is to configure an independent dust collector at the rear end of the heat exchanger. The external heat exchanger and the dust collector occupy a large amount of space and project cost, and the regular ash cleaning will also affect the continuous operation of the production line. Summary of the Invention

[0005] The problem to be solved by the present invention is that in the prior art, the desorption of VOCs in organic waste gas leads to an increase in energy consumption, and the external heat exchanger and the dust collector occupy a large amount of space and project cost; in addition, the regular ash cleaning will also affect the continuous operation of the production line and consume a large number of maintenance personnel, further increasing the labor and material costs.

[0006] To solve the above problems, the technical solution of the present invention provides a direct-fired furnace. The direct-fired furnace includes a heat exchange area and a combustion area. A heat exchange device is arranged in the heat exchange area, and a burner is arranged in the combustion area. The direct-fired furnace includes a first gas inlet, a first gas outlet, a second gas inlet, and a second gas outlet. The first gas inlet is adapted to inhale high-concentration organic waste gas to be treated, and the second gas inlet is adapted to inhale low-concentration up-to-standard gas formed after treatment. The heat exchange device includes a first heat exchanger and a second heat exchanger. The heating inlet end of the first heat exchanger is connected to the first gas inlet, the heating outlet end of the first heat exchanger communicates with the inlet of the combustion area, the heating inlet end of the second heat exchanger is connected to the second gas inlet, the heating outlet end of the second heat exchanger is connected to the second gas outlet, and the heated gas output from the second gas outlet is adapted to be introduced to heat and desorb the adsorbed volatile organic compounds. The cooling inlet end of the first heat exchanger communicates with the outlet of the combustion area, the cooling outlet end of the first heat exchanger is connected to the cooling inlet end of the second heat exchanger, and the cooling outlet end of the second heat exchanger communicates with the first gas outlet.

[0007] Optionally, the direct-fired furnace further includes a soot blower arranged at the top of the direct-fired furnace. The soot blower includes a soot blower nozzle extending into the heat exchange area and capable of spraying jet gas onto the surface of the heat exchange device.

[0008] Optionally, the soot blower further includes a rack and pinion lifting mechanism and a wheel-type rotating mechanism. The rack and pinion lifting mechanism is adapted to drive the soot blower nozzle to move up and down. The wheel-type rotating mechanism is arranged at the bottom of the soot blower and is adapted to drive the soot blower nozzle to rotate. The rack and pinion lifting mechanism is connected to the soot blower nozzle through a collar structure, and an opening for spraying the jet gas is provided at the bottom of the soot blower nozzle.

[0009] Optionally, the direct-fired furnace further includes a booster fan and a jet gas delivery pipe. The soot blower is connected to the first gas outlet through the jet gas delivery pipe. The booster fan is adapted to extract the hot flue gas discharged from the first gas outlet as the jet gas of the soot blower.

[0010] Optionally, a quick-release silica filter device and a differential pressure gauge are arranged at the first gas outlet. The differential pressure gauge is adapted to monitor the pressure difference across the quick-release silica filter device and alarm when the monitored pressure difference exceeds a predetermined value.

[0011] Optionally, the direct-fired furnace further includes a soot blower, a booster fan, and a jet gas delivery pipe disposed at the top of the direct-fired furnace. The soot blower includes a soot blower nozzle that extends into the heat exchange area and can eject jet gas onto the surface of the heat exchange device. The soot blower is connected to the filtered rear end of the quick-release silica filter device through the jet gas delivery pipe. The booster fan is adapted to extract the hot flue gas discharged from the first gas outlet and filtered by the quick-release silica filter device as the jet gas of the soot blower.

[0012] Optionally, the direct-fired furnace further includes a baffle with an adiabatic layer on the outside, and the inlet and outlet of the combustion area are separated by the baffle.

[0013] Optionally, a cooling device is built into the baffle. The cooling device includes an open-hole cooling pipe and a cooling interface. The open-hole cooling pipes are inserted into each partition within the baffle, and the open-hole cooling pipes in each partition are connected to the cooling interface. The cooling interface is adapted to export the heat inside the baffle under the action of negative pressure.

[0014] Optionally, the first heat exchanger is a primary heat exchanger, and the second heat exchanger is a secondary heat exchanger.

[0015] To solve the above problems, the technical solution of the present invention also provides an organic waste gas treatment system, including: a concentrator wheel, a first pipeline, a second pipeline, a third pipeline, and the above-mentioned direct-fired furnace; the concentrator wheel includes a wheel cooling outlet, a wheel desorption inlet, and a wheel desorption outlet; the first pipeline connects the wheel desorption outlet and the first gas inlet, the second pipeline connects the wheel cooling outlet and the second gas inlet, the third pipeline connects the second gas outlet and the wheel desorption inlet. The high-concentration organic waste gas to be treated and the low-concentration up-to-standard gas are both formed after being processed by the concentrator wheel. The concentrator wheel introduces the heating gas output from the second gas outlet to heat and desorb the volatile organic compounds adsorbed by it.

[0016] Optionally, a pipeline bypass valve is provided between the second pipeline and the third pipeline, and a first temperature control device is provided in the third pipeline. The first temperature control device is adapted to detect the gas temperature in the third pipeline and control the opening of the pipeline bypass valve when the gas temperature in the third pipeline exceeds a preset value.

[0017] Optionally, the second pipeline and the third pipeline are arranged in parallel in the vicinity.

[0018] Optionally, an intake valve is provided at the second gas inlet, and a second temperature control device is provided in the second pipeline. The second temperature control device is adapted to detect the gas temperature in the second pipeline and control the opening of the intake valve according to the detected temperature.

[0019] Optionally, the organic waste gas treatment system further includes a desorption fan. The first pipeline includes a first section of pipeline and a second section of pipeline. The high-concentration organic waste gas to be treated is sequentially transported from the rotary wheel desorption outlet through the first section of pipeline, the desorption fan, and the second section of pipeline to the first gas inlet.

[0020] Optionally, the organic waste gas treatment system further includes a smoke exhaust pipeline and an exhaust chimney. The first gas outlet is connected to the exhaust chimney through the smoke exhaust pipeline.

[0021] Optionally, the organic waste gas treatment system further includes an adsorption fan. The adsorption fan is respectively connected to the concentrator wheel and the exhaust chimney. The adsorption fan is adapted to suck the low-concentration up-to-standard gas discharged from the concentrator wheel and the hot flue gas discharged from the smoke exhaust pipeline, and positively push the hot flue gas to the exhaust chimney.

[0022] Optionally, the direct combustion furnace further includes a retaining wall with a heat insulation layer on the outside. The retaining wall is internally provided with a cooling device. The cooling device includes an open-hole cooling pipe and a cooling interface. The open-hole cooling pipe is inserted into each partition in the retaining wall. The open-hole cooling pipes in each partition are communicated with the cooling interface. The cooling interface is connected to the adsorption fan. The adsorption fan is also adapted to suck and export the heat in the retaining wall.

[0023] To solve the above problems, the technical solution of the present invention further provides an organic waste gas treatment method for the above organic waste gas treatment system, including:

[0024] Input the low-concentration organic waste gas into the concentrator wheel for concentration treatment to form a low-concentration up-to-standard gas and adsorb the volatile organic compounds in the low-concentration organic waste gas;

[0025] Extract a part of the low-concentration up-to-standard gas, transport it from the rotary wheel cooling outlet through the second pipeline to the second gas inlet, and output it from the second gas outlet after heat exchange and temperature rise by the second heat exchanger;

[0026] Transport the heated gas output from the second gas outlet through the third pipeline, and introduce it into the concentrator wheel through the rotary wheel desorption inlet to heat and desorb the volatile organic compounds adsorbed by it;

[0027] The high-concentration organic waste gas to be treated formed after heat desorption is transported from the rotary wheel desorption outlet through the first pipeline to the first gas inlet, and then transported to the inlet of the combustion area after heat exchange and temperature rise by the first heat exchanger;

[0028] The burner performs combustion treatment on the high-concentration organic waste gas to be treated after heating and preheating, and the gas after combustion treatment is sequentially cooled step by step by the first heat exchanger and the second heat exchanger from the outlet of the combustion area, and then discharged through the first gas outlet.

[0029] Compared with the prior art, the technical solution of the present invention has at least the following advantages:

[0030] (1) By integrating the first heat exchanger and the second heat exchanger inside the direct-fired furnace, on the one hand, the high-concentration organic waste gas to be treated is transported to the first heat exchanger for preheating and then sent to the combustion area of the direct-fired furnace for incineration. On the other hand, a part of the low-concentration qualified gas sucked is used to heat and desorb the adsorbed volatile organic compounds after being heated by the second heat exchanger. In this way, it can not only save the layout space of heat exchange equipment, but also cancel the connecting pipes between equipment, reduce the heat loss on the outer wall of the pipes, improve the heat exchange efficiency, and avoid the increase in energy consumption caused by adding electric heaters or burner supplementary combustion methods for desorbing VOCs in organic waste gas. Thus, the functions of heating the adsorption cold air (the low-concentration qualified gas formed after adsorbing the low-concentration organic waste gas) and preheating the high-concentration organic waste gas are realized simultaneously.

[0031] (2) By optimizing the design of the soot blower structure and setting it on the top of the direct-fired furnace, the soot blower nozzle extends into the heat exchange area of the direct-fired furnace to perform soot cleaning operations on the internal heat exchanger. The structure is simple, the cost is low, it is simple and reliable, and the entire soot cleaning operation process can be allowed to be an online operation. The overall system does not need to stop and go offline, ensuring the continuous operation of the production line, and greatly reducing the labor and material costs.

[0032] (3) By changing the injection gas (soot cleaning gas) used by the soot blower from traditional compressed air to the hot flue gas discharged from the direct-fired furnace, the reduction of heat exchange efficiency during online soot cleaning is avoided.

[0033] (4) By installing a cooling device inside the retaining wall of the direct-fired furnace, the retaining wall of the direct-fired furnace can be maintained at a lower temperature, avoiding high-temperature metal fatigue damage.

[0034] (5) By setting a pipeline bypass valve between the second pipeline and the third pipeline, and setting a first temperature control device on the third pipeline and a second temperature control device on the second pipeline. The first temperature control device is used for mixing and cooling when the temperature of the desorption hot air (that is, the heating gas formed after the low-concentration qualified gas is heated by the second heat exchanger) is higher than the set value, thereby realizing rapid mixing temperature control. The second temperature control device is used to control the opening degree of the intake valve in the first gas inlet according to the detected gas temperature in the second pipeline, so as to control the air volume entering the second heat exchanger.

[0035] (6) By designing a quick-release silica filtration device on the exhaust pipe of the heat exchanger, the problems of high cost and large floor area caused by separately setting up a dust collector are avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic plan structure diagram of the organic waste gas treatment system according to an embodiment of the present invention;

[0037] Figure 2 is a schematic three-dimensional structure diagram of the organic waste gas treatment system according to an embodiment of the present invention from one angle;

[0038] Figure 3 is a schematic three-dimensional structure diagram of the organic waste gas treatment system according to an embodiment of the present invention from another angle;

[0039] Figure 4 is a schematic horizontal sectional structure diagram of the direct combustion furnace according to an embodiment of the present invention;

[0040] Figure 5 is a schematic vertical sectional structure diagram of the direct combustion furnace according to an embodiment of the present invention;

[0041] Wherein: 1 - organic waste gas inlet, 2 - concentrator wheel, 3 - adsorption fan, 4 - exhaust chimney, 5 - outlet of wheel cooling, 6 - outlet of wheel desorption, 7 - inlet of wheel desorption, 8 - first temperature control device, 9 - second temperature control device, 10 - pipeline bypass valve, 11 - combustion-supporting fan, 12 - burner, 13 - desorption fan, 14 - first gas inlet, 15 - direct combustion furnace, 16 - second gas outlet, 17 - second gas inlet, 18 - first gas outlet, 19 - heat insulation layer, 20 - retaining wall, 21 - open-hole cooling pipe, 22 - cooling interface, 23a - first heat exchanger, 23b - second heat exchanger, 24 - soot blower nozzle, 25 - quick-release silica filtration device, 26 - differential pressure gauge, 27 - soot blower, 28 - wheel-type rotating mechanism, 29 - rack and pinion lifting mechanism, 30 - booster fan, 31 - second pipeline, 32 - third pipeline, 33 - first section of the first pipeline, 34 - second section of the first pipeline, 35 - smoke exhaust pipeline. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention will be given with reference to the accompanying drawings.

[0043] Reference Figures 1 to 3, an embodiment of the present invention provides an organic waste gas treatment system, which includes: a concentration wheel 2, a first pipeline (composed of a first section of pipeline 33 and a second section of pipeline 34 in this embodiment), a second pipeline 31, a third pipeline 32, and a direct combustion furnace 15; the concentration wheel 1 includes a wheel cooling outlet 5, a wheel desorption inlet 7, and a wheel desorption outlet 6; the direct combustion furnace 15 includes a heat exchange area and a combustion area, a heat exchange device is arranged in the heat exchange area, and a burner 12 is arranged in the combustion area; the direct combustion furnace 15 includes a first gas inlet 14, a first gas outlet 18, a second gas inlet 17, and a second gas outlet 16, the first gas inlet 14 is adapted to inhale the high-concentration organic waste gas to be treated, and the second gas inlet 17 is adapted to inhale the low-concentration up-to-standard gas formed after treatment; the first pipeline communicates the wheel desorption outlet 6 and the first gas inlet 14, the second pipeline 31 communicates the wheel cooling outlet 5 and the second gas inlet 17, the third pipeline 32 communicates the second gas outlet 16 and the wheel desorption inlet 7, the high-concentration organic waste gas to be treated and the low-concentration up-to-standard gas are both formed after being treated by the concentration wheel 2, and the concentration wheel 2 introduces the heating gas output from the second gas outlet 16 to heat and desorb the volatile organic compounds adsorbed by it.

[0044] In this embodiment, the organic waste gas treatment system further includes a desorption fan 13, the first pipeline includes a first section of pipeline 33 and a second section of pipeline 34, and the high-concentration organic waste gas to be treated is conveyed from the wheel desorption outlet 6 to the first gas inlet 14 through the first section of pipeline 33, the desorption fan 13, and the second section of pipeline 34 in sequence. The organic waste gas treatment system further includes a smoke exhaust pipeline 35 and an exhaust chimney 4, and the first gas outlet 18 is connected to the exhaust chimney 4 through the smoke exhaust pipeline 35.

[0045] In this embodiment, the organic waste gas treatment system further includes an adsorption fan 3, the adsorption fan 3 is respectively connected to the concentration wheel 2 and the exhaust chimney 4, and the adsorption fan 3 is adapted to suck the low-concentration up-to-standard gas discharged from the concentration wheel 2 and the hot flue gas discharged from the smoke exhaust pipeline 35, and push the hot flue gas to the exhaust chimney 4 for discharge under positive pressure.

[0046] In actual implementation, the concentrator wheel 2 can be a zeolite wheel concentrator device. Those skilled in the art know that its working principle is based on the processes of adsorption and desorption, and it is mainly used for the treatment of organic waste gas, especially suitable for occasions with large air volume and low concentration. Its core component is a rotating wheel filled with adsorbent, and the rotating wheel is divided into an adsorption zone, a regeneration zone, and a cooling zone. Adsorption process: When the waste gas passes through the adsorption zone, the microporous structure on the surface of the zeolite wheel selectively adsorbs volatile organic compounds (VOCs), and the purified gas is discharged up to the standard. The adsorbent uses hydrophobic zeolite material, which can maintain a stable adsorption efficiency in a high-humidity environment. Desorption process: When the adsorbent is saturated, the rotating wheel rotates to the regeneration zone, and the VOCs adsorbed on the zeolite are desorbed by using an electric heater or a burner supplementary combustion method to form high-concentration VOCs gas. These high-concentration gases then enter the incineration device for treatment and are converted into carbon dioxide and water. Cooling process: After desorption, the adsorbent is cooled in the cooling zone and then rotates to the adsorption zone again for a new round of adsorption.

[0047] Can be combined with Figure 1 and Figure 4 In this embodiment, the heat exchange device includes a first heat exchanger 23a and a second heat exchanger 23b. The heating inlet end of the first heat exchanger 23a is connected to the first gas inlet 14, the heating outlet end of the first heat exchanger 23a communicates with the inlet of the combustion area, the heating inlet end of the second heat exchanger 23b is connected to the second gas inlet 17, the heating outlet end of the second heat exchanger 23b is connected to the second gas outlet 16, and the heated gas output from the second gas outlet 16 is suitable for being introduced to heat and desorb the adsorbed volatile organic compounds; the cooling inlet end of the first heat exchanger 23a communicates with the outlet of the combustion area, the cooling outlet end of the first heat exchanger 23a is connected to the cooling inlet end of the second heat exchanger 23b, and the cooling outlet end of the second heat exchanger 23b communicates with the first gas outlet 18. In specific implementation, the first heat exchanger 23a is a primary heat exchanger, and the second heat exchanger 23b is a secondary heat exchanger.

[0048] The basic working mode of the organic waste gas treatment system in this embodiment is as follows:

[0049] Low-concentration organic waste gas enters the concentrator wheel 2 through the organic waste gas inlet 1 for concentration. After passing through the concentrator wheel 2, the clean gas is transported to the exhaust chimney 4 through the pipeline and the adsorption fan 3 for up-to-standard discharge. A part of the clean gas adsorbed by the concentrator wheel 2 is extracted from the wheel cooling outlet 5. This gas is transported through the second pipeline 31 to the second gas inlet 17, heated and raised in temperature through the second heat exchanger 23b. The gas after temperature rise enters the wheel desorption inlet 7 from the second gas outlet 16 through the third pipeline 32, and the gas after temperature rise is introduced into the concentrator wheel 2 through the wheel desorption inlet 7 to heat and desorb the zeolite wheel surface. The high-concentration organic waste gas formed after desorption is transported from the wheel desorption outlet 6 through the first section of the first pipeline 33 and the desorption fan 13 and then through the second section of the first pipeline 34 to the first gas inlet 14 (this inlet is the waste gas inlet of the direct combustion furnace). The high-concentration organic waste gas enters the interior of the direct combustion furnace 15 and is gradually heated and raised in temperature through the first heat exchanger 23a. The temperature of the high-concentration organic waste gas after preheating can reach 500 °C, thus saving a large amount of fuel required by the subsequent burner 12. The high-concentration organic waste gas after preheating enters the combustion area of the direct combustion furnace 15 through the channel above the retaining wall insulation layer 19 of the direct combustion furnace 15. When the high-concentration organic waste gas passes through the burner 12, the combustion-supporting fan 11 cooperates with the burner 12 to further raise the temperature of the high-concentration organic waste gas to above 850 °C. The organic waste gas undergoes a high-temperature oxidation reaction at this temperature to generate CO 2 、H 2 O, SiO 2 and other substances. The waste gas after the reaction enters the heat exchange area through the channel below the retaining wall 20 insulation layer of the direct combustion furnace 15. The waste gas after the reaction is gradually cooled through the first heat exchanger 23a and the second heat exchanger 23b in sequence. The low-temperature flue gas after cooling is discharged through the first gas outlet 18. After being discharged, the flue gas is filtered through the quick-disassembly silica filtering device 25 and then sent to the exhaust chimney 4 through the smoke exhaust pipeline 35 for up-to-standard discharge.

[0050] The gas treatment in the organic waste gas treatment system of this embodiment includes two paths. One path is that the high-concentration organic waste gas enters the concentrator wheel for desorption and concentration enhancement, then enters the direct combustion furnace and is preheated and raised in temperature through the internally integrated heat exchanger, and then directly enters the direct combustion furnace and is further heated by the burner for thermal oxidation, and then directly passes through the two-stage heat exchanger, and then through the air duct and the quick-disassembly silica filtering device and is then discharged to the chimney; the other path is that the low-concentration up-to-standard gas after being treated by the wheel enters the second heat exchanger for preheating from the concentrator wheel cooling outlet, and then returns to the concentrator wheel desorption inlet for use in desorbing the concentrated gas. The flow directions of the two paths of gas in the direct combustion furnace are as Figure 4 shown by the arrows in the figure.

[0051] In the present embodiment, the direct-fired furnace 15 has the first heat exchanger 23a and the second heat exchanger 23b built inside it, forming a direct-fired furnace integrated with desorption for the concentrator wheel and waste gas preheating. This can not only save the equipment layout space, but also eliminate the connecting pipes between equipment, reduce the heat loss on the outer wall of the pipes, improve the heat exchange efficiency, and avoid the increase in energy consumption caused by adding electric heaters or burner supplementary combustion for VOCs desorption in organic waste gas. The multiple built-in heat exchange modules can simultaneously heat the adsorbed cold air (the low-concentration up-to-standard gas formed after adsorbing low-concentration organic waste gas) and preheat the high-concentration organic waste gas.

[0052] It should be noted that although there are also technical solutions of "integrating one or more heat exchangers inside a direct-fired furnace" in the prior art, in such technical solutions, usually the high-concentration organic waste gas to be burned is better preheated in multiple stages, but no technical solution that can simultaneously heat the adsorbed cold air (the low-concentration up-to-standard gas formed after adsorbing low-concentration organic waste gas) for desorption of the concentrator wheel and preheat the high-concentration organic waste gas has been found. Therefore, the functions of the first heat exchanger and the second heat exchanger in the embodiments of the present invention are different. The first heat exchanger is used for preheating the high-concentration organic waste gas, and the second heat exchanger is used for heating and raising the temperature of the cold air for desorption. Therefore, the direct-fired furnace integrated with desorption for the concentrator wheel and waste gas preheating in the embodiments of the present invention still has outstanding substantive features and significant progress.

[0053] Combined with Figure 1 and Figure 5 , in the present embodiment, the direct-fired furnace 15 further includes a soot blower 27 provided on the top of the direct-fired furnace 15. The soot blower nozzle 24 included in the soot blower 27 extends into the heat exchange area and can spray the jet gas onto the surface of the heat exchange device.

[0054] Specifically, when implemented, the soot blower 27 further includes a rack and pinion lifting mechanism 29 and a wheel-type rotating mechanism 28. The rack and pinion lifting mechanism 29 is adapted to drive the soot blower nozzle 24 to move up and down, and the wheel-type rotating mechanism 28 is provided at the bottom of the soot blower 27 and is adapted to drive the soot blower nozzle 24 to rotate. The rack and pinion lifting mechanism 29 is connected to the soot blower nozzle 24 through a collar structure, and an opening for spraying the jet gas is provided at the bottom of the soot blower nozzle 24.

[0055] After the organic waste gas treatment system operates for a period of time, SiO will adhere to the surface of the heat exchange device. 2, at this time, the temperature control device 8 cannot reach the set temperature, and at this time, it is necessary to clean the surfaces of the first heat exchanger 23a and the second heat exchanger 23b. Therefore, it is necessary to start the soot blower 27 to blow soot. In the prior art, conventional soot blowers usually adopt a design with a screw inside a carriage, which has a complex structure and high cost. In response to this, in the technical solution of the present invention, the soot blower 27 is redesigned, and a gear-rack lifting mechanism 29 is used to drive the soot blower nozzle 24 to move up and down. The gear-rack lifting mechanism 29 is connected to the soot blower nozzle 24 by a collar structure to prevent the soot blower rack from rotating synchronously with the soot blower nozzle 24. At the same time, a wheel-type rotating mechanism 28 of the soot blower is arranged at the bottom of the soot blower 27 to drive the soot blower nozzle 24 to rotate. This design has a simple structure, low cost, and is simple and reliable. An opening is provided at the bottom of the soot blower nozzle 24, and gas is sprayed from the opening onto the surfaces of the first heat exchanger 23a and the second heat exchanger 23b to blow 2 off, and 2 is discharged through the first gas outlet 18 along with the gas. The entire soot blowing process is an on-line operation, and the organic waste gas treatment system does not need to stop and go offline.

[0056] In actual implementation, the soot blower 27 can be arranged at the exact middle position between the first heat exchanger 23a and the second heat exchanger 23b. Since the soot blower 27 is driven to move up and down by the gear-rack lifting mechanism 29, and at the same time, the wheel-type rotating mechanism 28 of the soot blower will also drive the soot blower nozzle 24 to rotate, the soot blower nozzle 24 will spray and blow in a spiral up and down between the first heat exchanger 23a and the second heat exchanger 23b to ensure that all heat exchanger tubes can be blown.

[0057] In this embodiment, the direct-fired furnace further includes a booster fan 30 and a jet gas delivery pipe (not marked in the drawings). The soot blower 27 is connected to the first gas outlet 18 through the jet gas delivery pipe, and the booster fan 30 is adapted to extract the hot flue gas discharged from the first gas outlet 18 as the jet gas of the soot blower 27.

[0058] Conventional design soot blowers use compressed air as the gas source. However, when cold compressed air is sprayed onto the surfaces of the first heat exchanger 23a and the second heat exchanger 23b through the soot blower nozzle 24, it simultaneously reduces the outer surface temperature of the heat exchange device and reduces the heat exchange efficiency during on-line soot cleaning. For this reason, in the embodiment of the present invention, the compressed air is changed to the hot flue gas discharged from the system. The booster fan 30 extracts the hot flue gas discharged from the first gas outlet 18 and sends it to the soot blower 27 for high-temperature on-line soot cleaning.

[0059] Combined with Figure 1 and Figure 5, in this embodiment, a quick-release silica filtering device 25 and a differential pressure gauge 26 are provided at the first gas outlet 18. The differential pressure gauge is adapted to monitor the pressure difference across the quick-release silica filtering device 25 and alarm when the monitored pressure difference exceeds a predetermined value. The two ends of the quick-release silica filtering device 25 respectively include a filtering front end and a filtering rear end. The soot blower 27 is connected to the filtering rear end of the quick-release silica filtering device 25 through the jet gas delivery pipe. The booster fan 30 extracts the hot flue gas discharged from the first gas outlet 18 and filtered by the quick-release silica filtering device 25 as the jet gas of the soot blower 27, so as to ensure that the jet gas applied by the soot blower 27 contains as little silica as possible, thereby improving the soot cleaning efficiency.

[0060] Containing SiO 2 The direct emission of flue gas will cause the dust detector on the exhaust chimney 4 to exceed the standard and alarm. Separately installing a dust collector has a high cost and occupies a large area. For this reason, in the technical solution of this embodiment, a quick-release silica filtering device 25 is designed at the first gas outlet 18. This device uses a cylindrical PTFE film to filter fine SiO 2 . This device adopts a quick-release structure. When the differential pressure gauge 26 detects that the pressure difference of the quick-release silica filtering device 25 exceeds the set value, the system alarms. At this time, only need to loosen the quick-release structure of the quick-release silica filtering device 25 and put in a new quick-release silica filtering device 25 to complete the on-line replacement. In this embodiment, the quick-release silica filtering device 25 is arranged on the exhaust pipe after the heat exchange of the direct-fired furnace, rather than a separately installed floor-standing device. The operator uses the top plane of the direct-fired furnace as the maintenance space to quickly replace the dust removal and filtering device on the pipe. In the technical solution of the present invention, the traditional floor-standing separate dust collector is changed to a quick-release silica filtering device 25 placed on the first gas outlet 18 of the direct-fired furnace. The differential pressure gauge 26 is used to judge whether the silica filtering device 25 is blocked, avoiding the high cost and large floor area of separately installing a dust collector.

[0061] Combined with Figure 1 and Figure 4, the direct-fired furnace 15 further includes a retaining wall 20 with a heat-insulating layer 19 on the outside, and the inlet and outlet of the combustion area are separated and formed by the retaining wall 20. In this embodiment, a cooling device is built into the retaining wall 20. The cooling device includes an open-hole cooling pipe 21 and a cooling interface 22. The open-hole cooling pipe 21 is inserted into each partition in the retaining wall 20, and the open-hole cooling pipes 21 in each partition are connected to the cooling interface 22. The cooling interface 22 is adapted to export the heat in the retaining wall 20 under the action of negative pressure. Specifically, when implemented, the heat in the retaining wall 20 can be exported under the action of negative pressure through the adsorption fan 3. It only needs to connect the cooling interface 22 to the adsorption fan 3, and the adsorption fan 3 can suck and export the heat in the retaining wall under the action of negative pressure.

[0062] Specifically, when implemented, the high-concentration organic waste gas to be treated enters the combustion area of the direct-fired furnace 15 from the heating outlet end of the first heat exchanger 23a. After being heated and thermally oxidized by the burner 12, it bypasses the retaining wall 20 and enters the outside of the pipes in the middle of the first heat exchanger 23a (the cooling inlet end of the first heat exchanger 23a). The retaining wall 20 has the function of increasing the residence time of the organic waste gas to be treated in the direct-fired furnace 15 to ensure the removal efficiency, and at the same time has the function of separating the inlet side and the outlet side of the direct-fired furnace 15. There is a heat-insulating layer 19 of the direct-fired furnace retaining wall 20 in the direct-fired furnace 15. This heat insulation uses ceramic fiber modules with high heat insulation effects, and the ceramic fiber modules are fixed to the periphery of the direct-fired furnace retaining wall 20 with heat-insulating nails. However, in the traditional design, the direct-fired furnace retaining wall forms a closed space, and the retaining wall cannot dissipate heat when the furnace body operates at a high temperature, and the temperature accumulates. The retaining wall structure will cause metal fatigue damage due to long-term high temperature. For this reason, in this embodiment, a built-in cooling device for the retaining wall is provided in the retaining wall 20, and the cooling device is formed by inserting the open-hole cooling pipe 21 into each partition in the direct-fired furnace retaining wall 20. The built-in cooling device of the retaining wall 20 is connected to the inlet pipe of the adsorption fan 3 through the cooling interface 22. The negative pressure at the inlet of the adsorption fan 3 sucks away the heat in the direct-fired furnace retaining wall 20, so that the retaining wall 20 of the direct-fired furnace 15 is maintained at a lower temperature, avoiding high-temperature metal fatigue damage.

[0063] In this embodiment, a pipeline bypass valve 10 is provided between the second pipeline 31 and the third pipeline 32. A second temperature control device 9 and a first temperature control device 8 are respectively provided in the second pipeline 31 and the third pipeline 32. The first temperature control device 8 is adapted to detect the gas temperature in the third pipeline 32 (i.e., the temperature of the desorption air used for desorption after heat exchange through the second heat exchanger 23b). When the temperature in the third pipeline 32 exceeds a preset value, the pipeline bypass valve 10 is controlled to open, and part of the cooling air enters the third pipeline 32 through the pipeline bypass valve 10 for mixing and cooling. In actual implementation, the second pipeline 31 and the third pipeline 32 are arranged in parallel in the vicinity, so that rapid mixing and temperature control can be achieved at a relatively short distance. In this embodiment, an intake valve (not shown in the figure) is further provided at the second gas inlet 17. The second temperature control device 9 is adapted to detect the gas temperature in the second pipeline 31 (i.e., the temperature of the cooling air output from the runner cooling outlet 5 of the concentrator runner 2). The second temperature control device 9 is adapted to detect the gas temperature in the second pipeline 31 and control the opening degree of the intake valve according to the detected temperature, so as to accurately control the appropriate air volume entering the second heat exchanger 23b.

[0064] The direct-fired furnace in this embodiment adopts an integrated design of heat exchange, dust removal and filtration, and cooling. The primary heat exchanger, secondary heat exchanger, soot blower, quick-disassembly silica filtration device, and cooling device in the retaining wall are all designed in the overall system of the direct-fired furnace, forming a "self-cleaning direct-fired furnace system for desorption and waste gas preheating of the concentrator runner", which reduces costs and floor space, and avoids the problems of needing to stop the machine for ash cleaning and consuming a large number of maintenance personnel. Moreover, the structure of the soot blower is optimized, with simple structure, high reliability and low cost. The direct-fired furnace 15 and the concentrator runner 2 are arranged close to each other, and all control valves can be maintained and operated using the top planes of the direct-fired furnace 15 and the concentrator runner 2, saving additional platform costs and space.

[0065] In addition, an embodiment of the present invention further provides an organic waste gas treatment method for the above organic waste gas treatment system, which includes: inputting low-concentration organic waste gas into the concentrator wheel for concentration treatment to form low-concentration up-to-standard gas and adsorb volatile organic compounds in the low-concentration organic waste gas; extracting a part of the low-concentration up-to-standard gas, transporting it from the outlet of the wheel cooler to the second gas inlet through the second pipeline, heating and raising the temperature through the second heat exchanger, and then outputting it from the second gas outlet; transporting the heated gas output from the second gas outlet through the third pipeline, and introducing it into the concentrator wheel through the desorption inlet of the wheel to heat and desorb the adsorbed volatile organic compounds; the high-concentration organic waste gas to be treated formed after heating and desorption is transported from the desorption outlet of the wheel to the first gas inlet through the first pipeline, heated and raised in temperature through the first heat exchanger, and then transported to the inlet of the combustion area; the burner performs combustion treatment on the high-concentration organic waste gas to be treated after heating and preheating, and the gas after combustion treatment is sequentially cooled step by step through the first heat exchanger and the second heat exchanger from the outlet of the combustion area, and then discharged through the first gas outlet.

[0066] In this embodiment, the organic waste gas treatment system includes a soot blower disposed on the top of the direct-fired furnace. The soot blower nozzle included in the soot blower extends into the heat exchange area. The organic waste gas treatment method further includes: when detecting that the gas temperature in the third pipeline is lower than the first predetermined value, starting the soot blower to spray the jet gas onto the surface of the heat exchange device.

[0067] In this embodiment, the organic waste gas treatment system includes a pipeline bypass valve disposed between the second pipeline and the third pipeline. The organic waste gas treatment method further includes: when detecting that the gas temperature in the third pipeline exceeds the second predetermined value, opening the pipeline bypass valve to introduce the gas in the second pipeline into the third pipeline through the pipeline bypass valve for mixing and cooling.

[0068] In this embodiment, the organic waste gas treatment system includes a quick-disassembly silica filtering device and a differential pressure gauge disposed at the first gas outlet. The organic waste gas treatment method further includes: when the differential pressure gauge monitors that the differential pressure across the quick-disassembly silica filtering device exceeds the third predetermined value, giving an alarm prompt to replace the quick-disassembly silica filtering device.

[0069] For the specific implementation of the organic waste gas treatment method of the organic waste gas treatment system, reference can also be made to the implementation of the above organic waste gas treatment system, which will not be elaborated here.

[0070] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A direct-fired furnace, characterized in that: The direct-fired furnace includes a heat exchange area and a combustion area, a heat exchange device is arranged in the heat exchange area, and a burner is arranged in the combustion area; the direct-fired furnace includes a first gas inlet, a first gas outlet, a second gas inlet, and a second gas outlet, the first gas inlet is suitable for inhaling high-concentration organic waste gas to be treated, and the second gas inlet is suitable for inhaling low-concentration standard-compliant gas formed after treatment; the heat exchange device includes a first heat exchanger and a second heat exchanger, the heating inlet end of the first heat exchanger is connected to the first gas inlet, the heating outlet end of the first heat exchanger is connected to the inlet of the combustion area, the heating inlet end of the second heat exchanger is connected to the second gas inlet, the heating outlet end of the second heat exchanger is connected to the second gas outlet, and the heating gas output by the second gas outlet is suitable for being introduced to heat and desorb the adsorbed volatile organic compounds; the cooling inlet end of the first heat exchanger is connected to the outlet of the combustion area, the cooling outlet end of the first heat exchanger is connected to the cooling inlet end of the second heat exchanger, and the cooling outlet end of the second heat exchanger is connected to the first gas outlet.

2. The direct-fired furnace according to claim 1, characterized in that: It also includes a soot blower arranged on the top of the direct-fired furnace, and the soot blower includes a soot blower nozzle extending into the heat exchange area, which can spray the injection gas to the surface of the heat exchange device.

3. The direct-fired furnace according to claim 2, characterized in that: The sootblower further comprises a rack and pinion lifting mechanism and a wheeled rotating mechanism. The rack and pinion lifting mechanism is suitable for driving the sootblower nozzle to move up and down. The wheeled rotating mechanism is arranged at the bottom of the sootblower and is suitable for driving the sootblower nozzle to rotate. The rack and pinion lifting mechanism is connected to the sootblower nozzle through a sleeve ring structure. The bottom of the sootblower nozzle is provided with an opening for ejecting the ejected gas.

4. The direct-fired furnace according to claim 2, characterized in that: It also includes a booster fan and an injection gas delivery pipe, the soot blower is connected to the first gas outlet through the injection gas delivery pipe, and the booster fan is suitable for extracting hot flue gas discharged from the first gas outlet as injection gas for the soot blower.

5. The direct-fired furnace according to claim 1, characterized in that: The first gas outlet is provided with a quick-detachable silica filter device and a differential pressure gauge, and the differential pressure gauge is suitable for monitoring the pressure difference at both ends of the quick-detachable silica filter device and alarming when the monitored pressure difference exceeds a predetermined value.

6. The direct-fired furnace according to claim 5, characterized in that: It also includes a soot blower, a booster fan and a jet gas delivery pipe arranged on the top of the direct-fired furnace. The soot blower includes a soot blower nozzle that extends into the heat exchange area and can spray jet gas onto the surface of the heat exchange device. The soot blower is connected to the filtering rear end of the quick-detachable silica filter device through the jet gas delivery pipe. The booster fan is suitable for extracting hot flue gas discharged from the first gas outlet and filtered by the quick-detachable silica filter device as the jet gas for the soot blower.

7. The direct-fired furnace according to claim 1, characterized in that: The direct-fired furnace also includes a retaining wall with an insulating layer on the outside, and the inlet and outlet of the combustion area are separated and formed by the retaining wall.

8. The direct-fired furnace according to claim 7, characterized in that: The retaining wall has a built-in cooling device, which includes a perforated cooling pipe and a cooling interface. The perforated cooling pipe is inserted into each partition in the retaining wall. The perforated cooling pipe of each partition is connected to the cooling interface. The cooling interface is suitable for extracting heat from the retaining wall under the action of negative pressure.

9. An organic waste gas treatment system, characterized in that: It comprises: a concentrating wheel, a first pipeline, a second pipeline, a third pipeline and a direct-fired furnace as claimed in any one of claims 1 to 8; the concentrating wheel comprises a wheel cooling outlet, a wheel desorption inlet and a wheel desorption outlet; the first pipeline connects the wheel desorption outlet and the first gas inlet, the second pipeline connects the wheel cooling outlet and the second gas inlet, the third pipeline connects the second gas outlet and the wheel desorption inlet, the high-concentration organic waste gas to be treated and the low-concentration standard gas are both formed after being treated by the concentrating wheel, and the concentrating wheel introduces the heating gas output from the second gas outlet to heat and desorb the volatile organic compounds adsorbed therein.

10. The organic waste gas treatment system according to claim 9, characterized in that: A pipeline bypass valve is arranged between the second pipeline and the third pipeline, and a first temperature control device is arranged in the third pipeline. The first temperature control device is suitable for detecting the gas temperature in the third pipeline and controlling the pipeline bypass valve to open when the gas temperature in the third pipeline exceeds a preset value.

11. The organic waste gas treatment system according to claim 10, characterized in that: The second pipeline and the third pipeline are arranged in parallel nearby.

12. The organic waste gas treatment system according to claim 9, characterized in that: The second gas inlet is provided with an intake valve, and the second pipeline is provided with a second temperature control device, which is suitable for detecting the gas temperature in the second pipeline and controlling the opening of the intake valve according to the detected temperature.

13. The organic waste gas treatment system according to claim 9, characterized in that: It also includes a desorption fan, the first pipeline includes a first section of the pipeline and a second section of the pipeline, and the high-concentration organic waste gas to be treated is transported from the desorption outlet of the rotor to the first gas inlet via the first section of the pipeline, the desorption fan and the second section of the pipeline in sequence.

14. The organic waste gas treatment system according to claim 9, characterized in that: It also includes a smoke exhaust pipe and an exhaust chimney, and the first gas outlet is connected to the exhaust chimney through the smoke exhaust pipe.

15. The organic waste gas treatment system according to claim 14, characterized in that: It also includes an adsorption fan, which is respectively connected to the concentrating wheel and the exhaust chimney. The adsorption fan is suitable for sucking low-concentration standard gas discharged from the concentrating wheel and hot flue gas discharged from the exhaust pipe, and pushing the hot flue gas to the exhaust chimney under positive pressure.

16. The organic waste gas treatment system according to claim 15, characterized in that: The direct-fired furnace also includes a baffle wall with an insulating layer on the outside, and the baffle wall has a built-in cooling device. The cooling device includes a perforated cooling pipe and a cooling interface. The perforated cooling pipe is inserted into each partition in the baffle wall. The perforated cooling pipe of each partition is connected to the cooling interface. The cooling interface is connected to the adsorption fan, and the adsorption fan is also suitable for sucking and exporting heat in the baffle wall.

17. An organic waste gas treatment method according to any one of claims 9 to 16, characterized in that: include: Inputting low-concentration organic waste gas into the concentrating rotor for concentration treatment to form low-concentration standard gas and adsorb volatile organic compounds in the low-concentration organic waste gas; Extracting part of the low-concentration gas that meets the standard, transporting it from the rotor cooling outlet to the second gas inlet through the second pipeline, and outputting it from the second gas outlet after heat exchange and temperature increase in the second heat exchanger; The heated gas outputted from the second gas outlet is transported through the third pipeline and introduced into the concentrating wheel through the desorption inlet of the wheel to heat and desorb the volatile organic compounds adsorbed thereon; The high-concentration organic waste gas to be treated formed after heating and desorption is transported from the desorption outlet of the rotary wheel to the first gas inlet through the first pipeline, and is transported to the inlet of the combustion area after being heated by the first heat exchanger; The burner burns the high-concentration organic waste gas to be treated after preheating, and the gas after combustion treatment is cooled step by step through the first heat exchanger and the second heat exchanger from the outlet of the combustion area, and then discharged through the first gas outlet.

18. An organic waste gas treatment method of the organic waste gas treatment system according to claim 17, characterized in that: The organic waste gas treatment system includes a soot blower arranged on the top of the direct-fired furnace, and the soot blower includes a soot blower nozzle extending into the heat exchange area. The organic waste gas treatment method also includes: when it is detected that the gas temperature in the third pipeline is lower than a first predetermined value, starting the soot blower to spray the injection gas onto the surface of the heat exchange device.

19. An organic waste gas treatment method of the organic waste gas treatment system according to claim 17, characterized in that: The organic waste gas treatment system includes a pipeline bypass valve arranged between the second pipeline and the third pipeline. The organic waste gas treatment method also includes: when it is detected that the gas temperature in the third pipeline exceeds a second predetermined value, the pipeline bypass valve is opened to introduce the gas in the second pipeline into the third pipeline through the pipeline bypass valve for mixing and cooling.

20. An organic waste gas treatment method of the organic waste gas treatment system as claimed in claim 17, characterized in that: The organic waste gas treatment system includes a quick-detachable silica filter device and a differential pressure gauge arranged at the first gas outlet. The organic waste gas treatment method also includes: when the pressure difference between the two ends of the quick-detachable silica filter device monitored by the differential pressure gauge exceeds a third predetermined value, an alarm is issued to prompt the replacement of the quick-detachable silica filter device.

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