Petrochemical tail gas recovery system

Abstract

The invention relates to the technical field of tail gas treatment, in particular to a petrochemical tail gas recovery system. Comprising a condensation kettle and a refrigerating system, an air inlet cavity and an air outlet cavity are horizontally formed in the upper end of the condensation kettle at intervals, a condensation cavity is formed in the condensation kettle and located below the air inlet cavity and the air outlet cavity, the air inlet cavity is connected with a condensation pipe, and the other end of the condensation pipe is communicated with the air outlet cavity; the bottom ends of the two sinking parts of the heart-shaped structure of the condensation pipe are connected with water return pipes, and a damping plate is arranged in the condensation pipe. And through vertical impact of two groups of cold air and guiding of the arc-shaped inner wall of the condensation cavity, spiral airflow is formed, a larger heat exchange area is achieved, and the condensation effect of equipment is improved. Tail gas is guided through the damping plate and prevented from flowing back into the water return pipe, and retention is reduced. The water seal is realized by utilizing the accumulation of the condensate water in the water return pipe; condensate water is not completely discharged during drainage, so that continuous existence of water seal is guaranteed, and tail gas is prevented from being discharged along with discharge of the condensate water.

Description

Technical Field

[0001] The invention relates to the technical field of tail gas treatment, and in particular to a petrochemical tail gas recovery system. Background Art

[0002] Gases volatilized, vented, or leaked from wellheads during the development, gathering, transportation, storage, and processing of oil and natural gas; gaseous wastes (volatile substances from paint and coatings, etc.) from machinery factories and other processing plants affiliated with oil and natural gas companies; non-condensable gases, released gases, reaction by-product gases, and waste gases from storage tank areas and sewage treatment processes generated by production equipment in refineries and petrochemical plants; all are petrochemical waste gases rich in various elements generated during the collection, transportation, and manufacturing of raw materials for petrochemical products.

[0003] In the past, pollutants emitted from petroleum waste gas had a significant impact on the health and lives of surrounding residents. For example, a gas pollutant called benzopyrene can induce cancer. It is emitted during the process of crude oil refining and fuel combustion, and is easily absorbed by floating dust in the atmosphere and enters the human body through breathing, and stays on the alveoli and bronchial walls for a long time. Therefore, petrochemical waste gas needs to be purified before it is discharged.

[0004] Petrochemical waste gas treatment processes usually include: 1. Collection: Collect waste gas from the production site through pipelines.

[0005] 2. Pretreatment: Remove solid particles and harmful gases from exhaust gas by physical or chemical methods.

[0006] 3. Adsorption: Use activated carbon and other adsorbents to adsorb harmful substances in exhaust gas.

[0007] 4. Catalysis: The harmful substances adsorbed on the activated carbon are completely decomposed through the action of the catalyst.

[0008] 5. Deep purification: Through activated carbon adsorption, desulfurization and denitrification, biological purification, CO, RCO, RTO and other technical means, the exhaust gas after catalytic oxidation is deeply purified to remove residual harmful substances.

[0009] Through the above process, petrochemical waste gas is treated. But generally speaking, the cost of the entire treatment process equipment is high, which is unaffordable for many small petroleum product processing plants. In addition, many equipments are large and scattered, making them difficult to place. Moreover, for small and medium-sized enterprises, the waste gas generated by their manufacturing is far from the upper limit of the treatment of common waste gas purification equipment, such as spray towers and condensation towers. The operation of the equipment will generate some air energy costs.

[0010] As for some process equipment, such as condensation, many enterprises use spiral condensation tubes to improve the condensation effect by extending the contact time with cold air. However, many condensation equipment face problems such as how to discharge the water vapor without stopping the machine or leaking it, and how to prevent it from being retained in the pipeline for a long time after condensation.

[0011] To this end, the present invention provides a petrochemical tail gas recovery system, which improves the condensate recovery structure in the condenser pipe in the condensation process to achieve water collection without stopping the condensation process and avoid the problem of tail gas leakage during water drainage as much as possible. Summary of the invention

[0012] The purpose of the present invention is to solve the problems existing in the prior art and to propose a petrochemical tail gas recovery system.

[0013] In order to achieve the above object, the present invention adopts the following technical solutions: A petrochemical tail gas recovery system comprises: a condensing kettle and a refrigeration system for circulating cooling for the condensing kettle, an air inlet cavity and an air outlet cavity are arranged horizontally at intervals inside the upper end of the condensing kettle, the air inlet cavity is connected to an air inlet pipe, the air outlet cavity is connected to an air outlet pipe, a condensing cavity is arranged below the air inlet cavity and the air outlet cavity in the condensing kettle, the air inlet cavity is connected to a condensing pipe, the other end of the condensing pipe is connected to the air outlet cavity after being spirally coiled in the condensing cavity, the lowermost rotating part of the condensing pipe is heart-shaped, the bottom ends of the two sinking parts of the heart-shaped structure of the condensing pipe are connected to a return pipe, the lower ends of the two return pipes are combined and connected to a valve, and a damping plate tilted in the gas flow direction is arranged on the inner bottom wall of the condensing pipe at the port connected to the return pipe; The refrigeration system includes a refrigerator and a cold storage chamber arranged on the refrigerator, the cold storage chamber is provided with two air outlets and an air inlet, the two air outlets of the cold storage chamber are respectively connected to cold air pipe 1 and cold air pipe 2, both cold air pipe 1 and cold air pipe 2 are inserted from the upper end of the condensing chamber and the ports inserted into the condensing chamber are arranged vertically; the lower end of the condensing chamber is connected to a return air pipe 3 that cooperates with the refrigerator.

[0014] Preferably, the undulation height of the upturned end of the damping plate does not exceed half of the inner diameter of the condenser tube.

[0015] Preferably, it also includes a primary filtering unit, which is arranged on the air inlet pipe and is used to filter large particles of impurities in the exhaust gas to prevent the large particles of impurities from condensing with water droplets and settling on the damping plate, thereby causing blockage of the pipeline in the condensing kettle.

[0016] Preferably, the primary filter unit is a pipeline filter.

[0017] Preferably, it also includes a secondary filter unit, which includes a spiral filter tube, which is connected to the outlet pipe via a flange structure, a flexible filter sleeve is embedded in the filter tube, both ends of the filter sleeve are provided with a screw barrel, a threaded tube is screwed on the inner thread of the screw barrel, an air hood for gas to pass through is provided in the threaded tube, and an adsorbent is filled between the two air hoods in the filter sleeve for secondary adsorption and purification of the exhaust gas; a flange plate that cooperates with the flange structure is screwed on the outer wall of the screw barrel, a rubber ring is sleeved on the outer tube wall of the matching part between the flange plate and the screw barrel thread, and the rubber tube is embedded in the filter tube port.

[0018] Preferably, the air inlet pipe, the air outlet pipe, the primary filter unit and the secondary filter unit are all redundantly arranged.

[0019] Preferably, a return air pipe is provided between the two air outlet pipes of the condensing kettle.

[0020] Preferably, a second air return pipe is provided between the first air return pipe and the air outlet of the secondary filter unit.

[0021] Preferably, at least one pressure relief valve is provided on the condensing kettle.

[0022] Preferably, a frame is also included.

[0023] Compared with the prior art, the present invention provides a petrochemical tail gas recovery system, which has the following beneficial effects: 1. The present invention forms a spiral airflow through two groups of vertical impacts of cold air and the guidance of the arc-shaped inner wall of the condensation chamber. With the spiral cooling tube, the petrochemical tail gas has more heat exchange area, which can more effectively utilize the heat exchange effect of the cold air and improve the condensation effect of the equipment. The cold air circulates and reduces the loss of cold air, which can reduce the working load pressure of the refrigerant. The tail gas is then guided by the upward structure of the damping plate to avoid the tail gas from flowing back into the return pipe and reduce the retention of the tail gas with the condensed water. At the same time, the accumulation of the condensed water itself in the return pipe is used to achieve the water seal effect of the return pipe. The condensed water is not completely removed during drainage to ensure the continuous existence of the water seal, thereby avoiding a small amount of retained tail gas from being discharged with the discharge of the condensed water.

[0024] 2. The spiral design of the filter tube of the present invention can not only extend the length of the adsorption channel, increase the contact time between the tail gas and the adsorbent, and improve the adsorption effect; it can also reduce the occupied space, reduce the volume of the equipment space, and facilitate transportation.

[0025] 3. The redundant configuration of the present invention can be used as a backup. When one set of pipelines fails or is under maintenance or replacement, the other set can be operated, so that the equipment can continue to operate without stopping.

[0026] 4. The present invention centralizes part of the petrochemical waste gas treatment process, reduces the volume of the tail gas recovery system, and reduces the floor space and external volume of the equipment.

[0027] Other advantages, objectives and features of the present invention will be described in part in the following description; and in part, will be apparent to those skilled in the art based on an examination of the following; or, may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a left-hand axial schematic diagram of the present invention.

[0029] Figure 2 It is a right-hand axial schematic diagram of the present invention.

[0030] Figure 3 It is a rear perspective schematic diagram of the present invention.

[0031] Figure 4 It is a front view schematic diagram of the present invention.

[0032] Figure 5 It is a rear view schematic diagram of the present invention.

[0033] Figure 6 It is a top view schematic diagram of the present invention after removing the frame.

[0034] Figure 7 It is a vertical cross-sectional schematic diagram of the condensing kettle and refrigeration system structure of the present invention.

[0035] Figure 8 It is a horizontal cross-sectional schematic diagram of the cold air pipe 1 and the cold air pipe 2 of the present invention located at the side of the condensing chamber.

[0036] Fig. 9 For the present invention Figure 7 Schematic diagram of the cross section of the condenser.

[0037] Fig.10 It is a schematic diagram of the heart-shaped structure at the lower end of the condenser tube of the present invention.

[0038] Fig.11 For the present invention Fig.10 Local schematic diagram of point A.

[0039] Fig.12 It is a cross-sectional schematic diagram of the isolation point between the air inlet cavity and the air outlet cavity of the present invention.

[0040] Fig.13 It is a three-dimensional schematic diagram of the filter sleeve assembly of the present invention.

[0041] Fig.14 It is a stereoscopic view of the filter sleeve of the present invention and a partial enlarged view of the port screw barrel.

[0042] Fig.15 It is the screw barrel assembly and explosion diagram of the present invention.

[0043] Fig.16 The figure is a cross-sectional schematic diagram of a spiral barrel assembly assembled in a filter tube of the present invention.

[0044] Fig.17 It is a cross-sectional view of the connection between the flange and the threaded pipe of the present invention.

[0045] Fig.18 It is a schematic diagram of the structure of the return pipe, water seal pipe and drainage pipe of the present invention.

[0046] In the figure: 1. frame; 2. condenser; 3. air inlet chamber; 4. air outlet chamber; 5. condensing chamber; 6. air inlet pipe; 7. air outlet pipe; 8. condensing pipe; 801. cooling pipe; 802. water collecting pipe; 803. water return pipe; 804. damping plate; 805. drain pipe; 9. refrigerator; 10. cold air pipe 1; 11. cold air pipe 2; 12. pressure relief valve; 13. return air pipe 3; 14. primary filter unit; 15. secondary filter unit; 1501. filter tube; 1502. filter sleeve; 1503. screw barrel; 1504. threaded pipe; 1505. air hood; 1506. handle; 1507. flange; 1508. flange 1; 1509. flange 2; 15010. rubber ring; 16. return air pipe 1; 17. return air pipe 2; 18. exhaust pipe; 19. water seal pipe. DETAILED DESCRIPTION

[0047] The following will be combined with the attached embodiment of the present invention Figure 1-18 , the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0048] Embodiment 1, in order to solve the problems existing in the prior art of how to discharge water vapor without stopping or leaking it, and how to prevent it from being retained in the pipeline for a long time after condensation, this embodiment provides a petrochemical tail gas recovery system, including: a condensing kettle 2 and a refrigeration system for circulating cooling to the condensing kettle 2, an air inlet chamber 3 and an air outlet chamber 4 are arranged horizontally at intervals inside the upper end of the condensing kettle 2, the air inlet chamber 3 is connected to an air inlet pipe 6, and the air outlet chamber 4 is connected to an air outlet pipe 7, a condensing chamber 5 is arranged below the air inlet chamber 3 and the air outlet chamber 4 in the condensing kettle 2, the air inlet chamber 3 is connected to a condensing tube 8, and the other end of the condensing tube 8 is connected to the air outlet chamber 4 after being spirally coiled in the condensing chamber 5, the lowermost rotating part of the condensing tube 8 is heart-shaped, and the bottom ends of the two sinking parts of the heart-shaped structure of the condensing tube 8 are connected to a return pipe 803, the lower ends of the two return pipes 803 are combined and connected to a valve 1, and a damping plate 804 tilted in the gas flow direction is arranged on the inner bottom wall of the condensing tube 8 at the port connected to the return pipe 803; The refrigeration system includes a refrigerator 9 and a cold storage chamber arranged on the refrigerator 9. The cold storage chamber is provided with an air outlet and an air inlet. The air outlet of the cold storage chamber is connected to a cold air pipe 10 and a cold air pipe 2 11 via a two-way valve. The cold air pipe 10 and the cold air pipe 2 11 are both inserted from the upper end of the condensing chamber 5 and the ports inserted into the condensing chamber 5 are arranged vertically; the lower end of the condensing chamber 5 is connected to a return air pipe 3 13 that cooperates with the refrigerator 9.

[0049] Principle details of this embodiment: A petrochemical tail gas recovery system, comprising: (1) Condensation kettle 2. The condensation kettle 2 includes an upper kettle body and a lower kettle body, both of which are hollow structures, forming a space for gas flow and cold air flow. The side walls of the upper kettle body and the lower kettle body are provided with a thermal insulation layer to prevent the cold air from exchanging heat with the outside and affecting the condensation efficiency. The lower end of the upper kettle body is open and provided with a groove, the upper end of the lower kettle body is embedded in the groove, and is fastened and installed by bolts to achieve a fastened connection between the upper kettle body and the lower kettle body. A sealing gasket is provided between the groove of the upper kettle body and the upper end surface of the lower kettle body to prevent leakage of the condensation kettle 2. The condensation kettle 2 is divided and non-integrated. After dismantling, the interior of the upper kettle body and the lower kettle body are exposed to provide a channel for laying internal pipes, and to achieve maintenance and replacement of internal equipment.

[0050] A partition is fixedly installed in the middle of the upper kettle body, and the hollow chamber of the upper kettle body is divided into an air inlet chamber 3 and an air outlet chamber 4 by the partition. The side wall of the air inlet chamber 3 is connected to an air inlet pipe 6 through valve 2, and petrochemical tail gas is injected into the air inlet chamber 3 through the air inlet pipe 6; the air outlet chamber 4 is connected to an air outlet pipe 7 through valve 3.

[0051] The hollow chamber in the lower kettle body is the condensation chamber 5, and a sealing plate is provided at the upper end of the condensation chamber 5, through which the air inlet chamber 3 and the air outlet chamber 4 in the upper kettle body are isolated from the condensation chamber 5 of the lower kettle body. The sealing plate is provided with embedded holes in the air inlet chamber 3 and the air outlet chamber 4, and a condensation tube 8 is embedded in the embedded hole in the air inlet chamber 3, and the other end of the condensation tube 8 penetrates into the air outlet chamber 4 from the embedded hole at the air outlet chamber 4.

[0052] The condenser 8 is divided into two parts: one part is a cooling tube 801 connected to two embedded holes, and the cooling tube 801 is spirally coiled from top to bottom; the other part is a water collecting pipe 802 that is in common with the bottom ends of the two cooling tubes 801. The water collecting pipe 802 is in an inverted heart shape, and the bottom ends of the two sinking parts of the water collecting pipe 802 are connected to the return pipe 803. The lower ends of the two return pipes 803 are close together and connected to the drain pipe 805 through valve 1. The drain pipe 805 passes through the condenser 2, and the drain pipe 805 is connected to the condensed water recovery tank outside the condenser 2 through a water pump (not shown in the attached figure). Two damping plates 804 are provided on the inner bottom wall of the water collecting pipe 802. The damping plate 804 is arranged at the port of the connecting part of the return pipe 803 and the water collecting pipe 802 facing the air inlet direction, and the damping plate 804 is tilted toward the gas flow direction.

[0053] (2) A refrigeration system for circulating cooling to the condensing chamber 5. The refrigeration system includes a refrigerator 9 and a cold storage chamber disposed on the refrigerator 9. The refrigeration system structure shown in the accompanying drawings is only a schematic diagram.

[0054] The refrigerator 9 is a gas compression refrigerator 9, which is composed of a compressor, a condenser, an evaporator, an expander, etc.

[0055] The cold storage chamber is provided with two air outlets and an air inlet. The two air outlets of the cold storage chamber are both connected to pumps, and the air outlets of the two pumps are respectively connected to cold air pipe 10 and cold air pipe 2 11. The other ends of cold air pipe 10 and cold air pipe 2 11 are both inserted into the condensing chamber 5, and the insertion position is located at the upper end of the condensing chamber 5. The air outlet end of cold air pipe 10 is inserted into the condensing chamber 5 horizontally and vertically, and the air outlet end of cold air pipe 2 11 is bent to the top of the condensing kettle 2, and passes through the partition and is inserted into the condensing chamber 5 from the upper end of the condensing chamber 5. The air outlet end of cold air pipe 10 is located below the air outlet end of cold air pipe 2 11, and the position relationship of the ports of cold air pipe 10 and cold air pipe 2 11 inserted into the condensing chamber 5 is close to the top wall of the condensing chamber 5 and is arranged vertically. The lower end of the condensing chamber 5 is connected to the return air pipe 3 13, and the other end of the return air pipe 3 13 is connected to the air inlet of the compressor.

[0056] According to the above technical solution: The concentrated petrochemical tail gas enters the air inlet chamber 3 from the air inlet pipe 6, and is collected in the air inlet chamber 3. Then it enters the condenser pipe 8, flows along the condenser pipe 8 to the air outlet chamber 4, and is finally discharged from the air outlet chamber 4 to the outside of the condenser kettle 2.

[0057] The gas compressed by the compressor is first cooled in the condenser, releasing heat to the cooling water (or air) in the condenser; then it flows through the regenerator and is further cooled by the reflux gas, and enters the expander for adiabatic expansion, and the pressure and temperature of the compressed gas decrease at the same time. When the gas expands in the expander, it does work externally and becomes part of the input work of the compressor.

[0058] The expanded low-temperature gas enters the cold storage chamber, and is then sucked into the two-way valve by the pump, and then input into the cold air pipe 10 and the cold air pipe 2 11. The cold air pipe 10 and the cold air pipe 2 11 are vertically blown into the condensation chamber 5, impacting on the condensation pipe 8, absorbing the heat of the petrochemical tail gas in the condensation pipe 8, and achieving the purpose of refrigeration.

[0059] The cold air blown into the condensation chamber 5 by the cold air pipe 10 and the cold air pipe 2 11 impacts vertically, thereby forming a spiral flow from top to bottom. The cold air with spiral flow has more heat exchange area than the traditional straight tube condenser. When the tail gas flows in the cold pipe 801, it can more fully exchange heat with the cold air, thereby increasing the heat transfer efficiency. The cold pipe 801 on the upper part of the condensation tube 8 is also spirally arranged to increase the retention time of the petrochemical tail gas in the condensation chamber 5, that is, to increase the heat exchange time, and the spiral structure makes the tail gas flow longer in the low temperature environment, and the heat exchange time with the petrochemical tail gas in the condensation tube 8 is longer, which can more effectively utilize the heat exchange effect of the cold air. In addition, in the spiral pipeline, the tail gas is subjected to the action of centrifugal and centripetal forces, generating secondary flow and vortex phenomena, so that the tail gas can exchange heat with the tube wall both inside and outside, further improving the heat transfer efficiency. Multi-phase coordination improves the condensation effect to improve the removal rate of water vapor in the petrochemical tail gas. After that, the gas flows back into the compressor from the return air pipe 3 13, exchanges heat with the compressed gas, and then enters the compressor to be compressed. The cold air circulation can improve the utilization rate and reduce the load pressure of the refrigerator 9 for continuous refrigeration.

[0060] The condensed water vapor first flows along the wall of the condenser tube 8, and then accumulates in the sinking part of the water collecting pipe 802. A part of the deposited condensate waits to overflow the damping plate 804 and then flows into the return pipe 803; the other part flows along the damping plate 804 directly into the return pipe 803 with the flow impact pressure of the petrochemical tail gas in the pipe. The condensed water gathers in the return pipe 803, and the discharge of the condensed water is controlled by opening and closing the valve 1, thereby completing the collection and discharge of the condensed water.

[0061] Through the above scheme, not only can the condensation effect of the equipment be improved and the workload pressure of the refrigerator 9 be reduced; but also, through the structural coordination of the damping plate 804, the exhaust gas flow can be guided to reduce the accumulation of exhaust gas in the return pipe 803; at the same time, the condensed water itself is used to achieve the water seal of the return pipe 803 to reduce the exhaust gas leakage during drainage.

[0062] In summary, this solution forms a spiral airflow by means of two groups of vertical impacts of cold air and the guidance of the arc-shaped inner wall of the condensation chamber 5. In combination with the spiral cooling tube 801, the petrochemical tail gas has more heat exchange area, which can more effectively utilize the heat exchange effect of the cold air and improve the condensation effect of the equipment. The circulation of cold air reduces the loss of cold air and can reduce the working load pressure of the refrigerant. The upward structure of the damping plate 804 guides the tail gas, thereby preventing the tail gas from flowing back into the return pipe 803 and reducing the retention of the tail gas with the condensed water. At the same time, the accumulation of the condensed water itself in the return pipe 803 is used to achieve the water seal effect of the return pipe 803, which is not completely eliminated during drainage, ensuring the continuous existence of the water seal, thereby preventing a small amount of retained tail gas from being discharged with the discharge of the condensed water.

[0063] In this embodiment, the output power of the pump corresponding to the cold air pipe 10 is greater than the output power of the pump corresponding to the cold air pipe 2 11, so that the impact force of the cold air blown horizontally into the condensing chamber 5 is greater than the impact force of the cold air blown vertically into the condensing chamber 5, so as to ensure that the two-phase cold air impacts and mixes on the inner wall of the condensing chamber 5, and diffuses under the guidance of the chamber wall, and because of the vertical impact of the cold air pipe 2 11, a spiral airflow is formed. Preferably, a spiral guide plate can be set in the condensing chamber 5 at the position facing the outlet end of the condenser tube, and the airflow impact is guided by the guide plate to form a spiral airflow. Or as shown in the attached Figure 8 As shown, the insertion positions of the cold air pipe 10 and the cold air pipe 2 11 are located at the side of the condensing chamber 5, directly hitting the arc-shaped inner wall of the condensing chamber 5 to guide the flow of cold air.

[0064] In this embodiment, the damping plate 804 is tilted toward the gas flow direction, thereby guiding the gas. When the gas is continuously impacted by the air pressure on the rear side during the flow, it will not flow back into the return pipe 803 along the damping plate 804, thereby reducing the accumulation of tail gas in the return pipe 803. When the condensed water is required to be discharged at the same time, after the valve is closed, a part of the condensed water still exists in the return pipe 803, and the condensed water in the return pipe 803 is used to achieve a water seal on the return pipe 803, thereby reducing the leakage of petrochemical tail gas after the valve is opened.

[0065] In this embodiment, shaft seals are provided between the cold air pipe 1 10, the cold air pipe 2 11, the air inlet pipe 6, the air outlet pipe 7, the drain pipe 805, the return air pipe 3 13 and the condensing kettle 2 to achieve pipeline installation sealing to prevent exhaust gas and cold air leakage.

[0066] In this embodiment, a heat insulating layer is also provided on the sealing plate to prevent the moisture in the exhaust gas from condensing in the air intake cavity 3, thereby increasing the difficulty of subsequent cleaning.

[0067] In this embodiment, the horizontal projection of the damping plate 804 shields the connection portion between the return pipe 803 and the water collecting pipe 802 to prevent the exhaust gas from flowing back into the return pipe 803. The undulating height L2 of the upturned end of the damping plate 804 does not exceed half of the inner diameter L1 of the condenser pipe 8, so as to prevent the condensed water from gathering at the sinking place of the water collecting pipe 802 below the condenser pipe 8 and closing the pipe opening, thereby affecting the flow of the exhaust gas.

[0068] In this embodiment, since both ends of the filter tube 1501 penetrate the air inlet cavity 3 and the air outlet cavity 4 respectively, multiple groups of filter tubes 1501 can be provided to achieve multi-pipeline condensation with higher efficiency.

[0069] In this embodiment, a frame 1 is also included, which provides an installation base for various devices, such as a condenser 2 and a refrigeration system, and provides a bracket support for pipelines such as an air inlet pipe 6 and an air outlet pipe 7.

[0070] Embodiment 2, in a further embodiment of the present invention, a primary filter unit 14 is further included, which is arranged on the air intake pipe 6. The primary filter unit 14 is a pipeline filter, and a filter element is arranged inside. The filter element is used to filter large particles of impurities in the exhaust gas, so as to prevent the large particles of impurities from condensing and settling on the damping plate 804 with the water droplets, thereby clogging the pipeline in the condensing kettle 2.

[0071] It also includes a secondary filter unit 15, which is used to perform adsorption filtration on the exhaust gas after condensation. The secondary filter unit 15 includes a spiral filter tube 1501, the air inlet of the filter tube 1501 is docked with the outlet pipe 7 of the outlet cavity 4, and the air outlet of the filter tube 1501 is docked with an external exhaust pipe 18, and the exhaust gas after passing through the filter tube 1501 is transferred to the next process through the exhaust pipe 18. The air inlet and outlet of the filter tube 1501 are both provided with flange 1508, and the air outlet of the outlet pipe 7 and the air inlet of the exhaust pipe 18 are both provided with flange 2 1509. Flange 1 1508 and flange 2 1509 are fastened and connected by bolts to realize the detachable connection between the filter tube 1501 and the outlet pipe 7, which is used to receive the exhaust gas after condensation. And a sealing gasket 2 is sandwiched between flange 1508 and flange 2 1509 to enhance the sealing performance.

[0072] A flexible filter sleeve 1502 is embedded in the filter tube 1501, and the filter sleeve 1502 can be bent and deformed according to the spiral shape of the filter tube 1501. A screw barrel 1503 is provided at both ends of the filter sleeve 1502, and a threaded tube 1504 is screwed into the inner thread of the screw barrel 1503. The threaded tube 1504 is provided with a gas cover 1505 for gas to pass through and a handle 1506 for pulling and traction. The filter sleeve 1502 is filled with an adsorbent between the two gas covers 1505, which is used for secondary adsorption and purification of the exhaust gas. A flange 1507 that matches the flange structure is screwed into the outer wall of the screw barrel 1503, and a rubber ring 15010 is sleeved on the outer tube wall of the portion where the flange 1507 and the screw barrel 1503 thread match, and the rubber tube is embedded in the port of the filter tube 1501.

[0073] Through the above technical solution: During installation, hold the handle 1506, screw the threaded tube 1504 into the screw barrel 1503 at either end of the filter sleeve 1502, and seal one end of the filter sleeve 1502 through the air cover 1505; then fill the filter sleeve 1502 with the adsorbent; then screw the threaded tube 1504 at the other end into the corresponding screw barrel 1503; intercept the adsorbent in the filter sleeve 1502 through the two air covers 1505, and complete the assembly of the filtering structure. Then screw a flange 1507 onto the screw barrel 1503, hang the filter tube 1501 vertically, and then insert the screw barrel 1503 without screwing the flange 1507 into the filter tube 1501, and gradually convey it so that the filter sleeve 1502 passes through the filter tube 1501 (since the filter tube 1501 is spirally arranged and the spiral density is relatively large, when installing the filter sleeve 1502, the iron wire or steel strand can be first passed through the filter tube 1501, and then tied to the handle 1506, and the filter sleeve 1502 is pulled through the filter tube 1501 by pulling. The specific operation depends on the actual operation on site), and embed the installed flange 1507 into the inlet of the filter tube 1501, and the flange of the flange 1507 is against the inlet of the filter tube 1501 Flange 1508; then screw another flange 1507 onto another screw barrel 1503 of the filter sleeve 1502, and embed the flange 1507 into the outlet of the filter tube 1501, and the flange of the flange 1507 rests on the flange 1508 at the outlet of the filter tube 1501, so that the filter sleeve 1502 is embedded in the filter tube 1501, and the filter sleeve 1502 is restricted by the flanges 1507 at both ends, so as to prevent the filter sleeve 1502 from being offset and twisted due to the impact of exhaust gas; and the gap between the flange 1507 and the filter tube 1501 is closed by a rubber ring 15010 arranged outside the flange 1507, so that the exhaust gas can only pass through the flange at the pipe joint, so as to prevent the exhaust gas from leaking out from the gap. Then, flange 1 1508 at both ends of the filter tube 1501 is connected to flange 2 1509 on the outlet pipe 7 and the exhaust pipe 18 respectively, and fastened by bolts, so as to realize the installation of the filter tube 1501.

[0074] During disassembly and assembly, unscrew the bolts, remove the filter tube 1501, and then unscrew the flange 1507 from the screw barrel 1503, and then pull the filter sleeve 1502 out of the filter tube 1501 to complete the disassembly of the filter sleeve 1502. Then unscrew the threaded tubes 1504 on the screw barrels 1503 at both ends, and pour out the adsorbent in the filter sleeve 1502. You can replace the new adsorbent, or you can recycle the adsorbent after desorption (heating desorption, using nitrogen as a carrier to carry heat to heat the adsorbent, so that the adsorbent is removed. Nitrogen is an inert gas and can protect the safety of the adsorbent at high temperatures).

[0075] In summary, the spiral design of the filter tube 1501 can not only extend the length of the adsorption channel, increase the contact time between the exhaust gas and the adsorbent, and improve the adsorption effect, but also reduce the occupied space, reduce the volume of the equipment space, and facilitate transportation.

[0076] In this solution, the outer diameters of the threaded tube 1504 and the spiral barrel 1503 are smaller than the inner diameter of the filter tube 1501 , forming a movable space to facilitate installation and movement in the spirally bent filter tube 1501 .

[0077] In this embodiment, the filter sleeve 1502 is made of plastic synthetic fiber or polyurethane film and is airtight, thereby preventing the exhaust gas in the filter sleeve 1502 from passing through the filter sleeve 1502 and directly flowing through the gap between the filter sleeve 1502 and the inner wall of the filter tube 1501 without being filtered by the adsorbent.

[0078] In this embodiment, the threaded tube 1504 is screwed into the screw barrel 1503, and the two ends of the filter sleeve 1502 are closed by the air hood 1505 on the threaded tube 1504, instead of directly setting the air hood 1505 at the port of the flange 1507. The purpose is to screw the threaded tube 1504 into the screw barrel 1503 without occupying the external volume, so as to achieve the sealing of the two ends of the filter sleeve 1502 without affecting the traction and embedding in the filter tube 1501 after filling the adsorbent.

[0079] In this embodiment, the diameter of the filter tube 1501 is smaller than half of the outlet pipe 7 (the figure shows only a schematic diagram, and the size is subject to the text description). By reducing the diameter of the tube, the pressure of the exhaust gas filled into the filter tube 1501 is increased. The increase in air pressure can also increase the adsorption amount of the adsorbent material and extend the time for the adsorbent to reach adsorption saturation, that is, increase the single use time of the adsorbent and reduce the frequency of disassembly and replacement.

[0080] In this embodiment, the adsorbent is activated carbon fiber (ACF), which is fibrous. After high-temperature activation, the fiber surface is covered with micropores (i.e., the positions occupied by hydrogen and oxygen before volatilization). The fiber diameter of the activated carbon fiber is 5-20 μm, the average specific surface area is 1000-1500 m2 / g, the average pore size is 1.0-4.0 nm, and the micropores are evenly distributed on the fiber surface. Activated carbon fiber can adsorb organic substances such as hydrocarbons (benzene, toluene, xylene, trimethylbenzene, n-hexane, cyclohexane, etc.), halogenated hydrocarbons (chloromethane, dichloromethane, trichloromethane, trichloroethylene, trichloroethane, bromomethane, tetrachloride, etc.), aldehydes and ketones (acetone, cyclohexanone, formaldehyde, acetaldehyde, furfural, etc.), esters (ethyl acetate, butyl acetate, etc.), ethers (methyl ether, ethyl ether, methyl ethyl ether, etc.), alcohols (methanol, ethanol, isopropanol, butanol, etc.), polymerization monomers (vinyl chloride, etc.) for air purification, which can effectively remove various harmful and odorous substances in exhaust gas, especially carcinogens and aromatic compounds (such as benzene, aldehydes). Compared with activated carbon, activated carbon fiber has small and uniform pore size, simple structure and large specific surface area. Therefore, activated carbon fiber has a faster adsorption rate for adsorbing small molecules, a higher adsorption rate, and is also easy to desorb.

[0081] In this embodiment, a filter cloth made of non-woven fabric is provided in the middle of the filter sleeve 1502, and the filter sleeve 1502 is divided into two installation cavities by the filter cloth, and the inlet and outlet of the two groups of screw barrels 1503 are respectively engraved with numbers: 1# and 2#. The micropore diameter of the adsorbent filled in the installation cavity of the filter sleeve 1502 corresponding to 1# is larger than the micropore diameter of the adsorbent filled in the installation cavity of the filter sleeve 1502 corresponding to 2#. The adsorption capacity of the adsorbent corresponding to the inlet direction of the filter sleeve 1502 is smaller than the adsorption capacity of the adsorbent in the outlet direction of the filter sleeve 1502. Compared with all adsorbents of the same grade, after the exhaust gas is injected, the exhaust gas is first concentrated at the inlet to be adsorbed and purified, so that the adsorption amount of the adsorbent at the inlet reaches saturation earlier, which may cause the coarse pores of the passage for the adsorbate molecules on the adsorbent to pass through to be blocked, thereby affecting the subsequent delivery of the exhaust gas, so that the adsorbent at the rear may be large enough to be saturated and needs to be replaced in advance. The two installation chambers are arranged in different levels, so that the saturation time of the adsorbent in the front is prolonged, and the time difference with the saturation time of the adsorbent in the rear is shortened as much as possible, that is, the time difference for the adsorbent in the filter sleeve 1502 to reach the saturation amount is shortened, and the overall use time is extended. (For example, when the adsorbent is granular activated carbon, the pore size of the granular activated carbon in the 1# installation chamber is 5-10nm, and the pore size of the granular activated carbon in the 2# installation chamber is 0-5nm. When it is activated carbon fiber, the micropore size of the activated carbon fiber in the 2# installation chamber is also smaller than the micropore size of the activated carbon fiber in the 1# installation chamber).

[0082] Embodiment 3, in a further embodiment of the present scheme, the air inlet pipe 6, the air outlet pipe 7, the primary filter unit 14, and the secondary filter unit 15 are all redundantly arranged, and the connected pipe ports are all provided with stop valves. That is, two air inlet pipes 6 and two air outlet pipes 7 are provided, and the two air inlet pipes 6 are both connected to the primary filter unit 14, and the two air outlet pipes 7 are both connected to the secondary filter unit 15. In this way, one can be used in reserve, and when one set of pipelines fails or is under maintenance or replacement, the other set can be operated, so that the equipment can be operated continuously and non-stop operation can be achieved.

[0083] In this embodiment, a return pipe 16 is provided between the two outlet pipes 7 of the condensing kettle 2, and the return pipe 16 is connected to the two outlet pipes 7 through a reversing valve, so that fluid reversal can be achieved. A channel is set up between the two outlet pipes 7 through the return pipe 16. During normal operation, the connecting port between the return pipe 16 and the outlet pipe 7 on the reversing valve is closed, while the channel between the outlet pipe 7 and the filter tube 1501 is connected. When a group of outlet pipes 7 and the secondary filter unit 15 or the pipeline, valve, etc. on the secondary filter unit 15 leak or are urgently damaged, or when the stop valve between the outlet pipe 7 and the outlet cavity 4 leaks, a temporary channel can be formed through the return pipe 16, so that the tail gas in the 1# outlet pipe 7 is first input into the 2# outlet pipe 7 for transportation and purification. An emergency temporary channel is set up between the outlet pipe 7 and the corresponding equipment through the return pipe 16 to improve the operating safety of the equipment.

[0084] In this embodiment, a return air pipe 2 17 is provided between the return air pipe 1 16 and the air outlet of a certain secondary filter unit 15. For example, a return air pipe 2 17 is connected between the air outlet of the 1# filter tube 1501 in the secondary filter unit 15 corresponding to the 1# outlet pipe 7 and the outlet pipe 7, and a reversing valve is also provided between the return air pipe 2 17 and the air outlets of the return air pipe 1 16 and the filter tube 1501. An additional exhaust gas delivery channel of the outlet pipe 7, the 1# secondary filter unit 15, the return air pipe 2 17, the return air pipe 1 16, the 2# secondary filter unit 15, and the exhaust pipe 18 can be formed, so that the exhaust gas passes through two groups of secondary filter units 15 connected in series for adsorption filtration, which can cope with the situation where the concentration of harmful substances in the exhaust gas is high or the filtering accuracy requirement is high, so as to improve the filtering accuracy and filtering effect.

[0085] In this embodiment, at least one pressure relief valve 12 is provided on the condensing kettle 2. For example, the air inlet chamber 3, the air outlet chamber 4, and the condensing chamber 5 are all provided with pressure relief valves 12 for balancing and regulating the air pressure to avoid equipment and pipeline bursting due to excessive pressure.

[0086] In this solution, the lower ports of the two groups of return pipes 803 are connected to form a U-shaped pipe. The bottom end of the U-shaped pipe is provided with a pipeline interface, and the pipeline interface is connected to valve 1. The opening and closing of the sinking part of the U-shaped pipe is controlled by valve 1, and then the condensed water in the return pipe 803 is controlled to be discharged to the drain pipe 805. In order to always ensure the water seal effect in the return pipe 803, the S-shaped water seal pipe 19 placed on the side can also be docked at the pipeline interface, and the water seal pipe 19 is then docked with the drain pipe 805 through valve 1. Through the curve design of the water seal pipe 19, it is ensured that there is always accumulated water in the water seal pipe 19, so that there is no need to control the drainage volume of the drain pipe 805, and the continuous existence of the water seal can be guaranteed, reducing the drainage requirements. The side wall of the sinking pipeline of the water seal pipe 19 is provided with an emptying valve. During cleaning, the condensed water accumulated in the water seal pipe is drained outside the emptying valve to avoid the accumulation of condensed water for a long time and the generation of odor.

[0087] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0088] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0089] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A petrochemical tail gas recovery system, characterized in that: include: A condenser (2) and a refrigeration system for circulating cooling for the condenser (2), wherein an air inlet chamber (3) and an air outlet chamber (4) are arranged horizontally at intervals inside the upper end of the condenser (2), the air inlet chamber (3) is connected to an air inlet pipe (6), and the air outlet chamber (4) is connected to an air outlet pipe (7), a condensation chamber (5) is arranged below the air inlet chamber (3) and the air outlet chamber (4) in the condenser (2), the air inlet chamber (3) is connected to a condensation pipe (8), the other end of the condensation pipe (8) is connected to the air outlet chamber (4) after being bent and coiled in the condensation chamber (5), the lowermost rotating part of the condensation pipe (8) is heart-shaped, the bottom ends of the two sinking parts of the heart-shaped structure of the condensation pipe (8) are connected to a return pipe (803), the lower ends of the two return pipes (803) are combined and connected to a valve, and a damping plate (804) tilted in the gas flow direction is arranged on the inner bottom wall of the condensation pipe (8) at the port connected to the return pipe (803); The refrigeration system comprises a refrigerator (9) and a cold storage chamber arranged on the refrigerator (9), the cold storage chamber being provided with two air outlets and an air inlet, the two air outlets of the cold storage chamber being respectively connected to a cold air pipe 1 (10) and a cold air pipe 2 (11), the cold air pipe 1 (10) and the cold air pipe 2 (11) being both inserted from the upper end of the condensing chamber (5) and the ports inserted into the condensing chamber (5) being arranged vertically; the lower end of the condensing chamber (5) is connected to a return air pipe 3 (13) cooperating with the refrigerator (9).

2. A petrochemical tail gas recovery system according to claim 1, characterized in that: The height of the upturned end of the damping plate (804) does not exceed half the inner diameter of the condenser tube (8).

3. A petrochemical tail gas recovery system according to claim 1, characterized in that: It also includes a primary filtering unit (14) disposed on the air intake pipe (6) and used to filter large impurities in the exhaust gas to prevent the large impurities from condensing with water droplets and settling on the damping plate (804) and causing blockage in the pipeline in the condensing kettle (2).

4. A petrochemical tail gas recovery system according to claim 3, characterized in that: The primary filter unit (14) is a pipeline filter.

5. The petrochemical tail gas recovery system according to claim 1, characterized in that: The invention also comprises a secondary filtering unit (15), wherein the secondary filtering unit (15) comprises a spiral filter tube (1501), the filter tube (1501) being connected to the gas outlet pipe (7) via a flange structure, a flexible filter sleeve (1502) being embedded in the filter tube (1501), a screw barrel (1503) being provided at both ends of the filter sleeve (1502), a threaded tube (1504) being screwed into the inner thread of the screw barrel (1503), a gas hood (1505) being provided in the threaded tube (1504) for gas to pass through, an adsorbent being filled between the two gas hoods (1505) in the filter sleeve (1502) for secondary adsorption and purification of the tail gas; a flange plate (1507) being screwed into the outer wall of the screw barrel (1503) for matching with the flange structure, a rubber ring (15010) being sleeved on the outer tube wall of the portion where the flange plate (1507) and the screw barrel (1503) are screwed into the thread, and the rubber tube is embedded in the port of the filter tube (1501).

6. A petrochemical tail gas recovery system according to any one of claims 1 to 5, characterized in that: The air inlet pipe (6), the air outlet pipe (7), the primary filter unit (14), and the secondary filter unit (15) are all redundantly arranged.

7. A petrochemical tail gas recovery system according to claim 6, characterized in that: An air return pipe (16) is provided between the two air outlet pipes (7) of the condensing kettle (2).

8. A petrochemical tail gas recovery system according to claim 7, characterized in that: A second air return pipe (17) is provided between the first air return pipe (16) and the air outlet of the secondary filter unit (15).

9. A petrochemical tail gas recovery system according to claim 1, characterized in that: At least one pressure relief valve (12) is provided on the condensing kettle (2).

10. A petrochemical tail gas recovery system according to claim 3, characterized in that: Also included is a frame (1).

Images