A petrochemical tail gas recovery system

Abstract

The present invention relates to the technical field of tail gas treatment, and in particular to a petrochemical tail gas recovery system. It includes: a condensation kettle and a refrigeration system. Inside the upper end of the condensation kettle, an intake cavity and an outlet cavity are horizontally arranged at intervals. Inside the condensation kettle, a condensation cavity is arranged below the intake cavity and the outlet cavity. The intake cavity is connected with a condensation pipe, and the other end of the condensation pipe is communicated with the outlet cavity. The lowest turning part of the condensation pipe is heart-shaped, and water return pipes are connected to the bottoms of the two sunken parts of the heart-shaped structure of the condensation pipe. A damping plate is arranged inside the condensation pipe. Through the vertical impact of two groups of cold air and the guidance of the arc-shaped inner wall of the condensation cavity, a spiral air flow is formed automatically, which has a larger heat exchange area and improves the condensation effect of the equipment. Through the guidance of the damping plate for the tail gas, the tail gas is prevented from flowing back into the water return pipe, reducing the retention; by using the accumulation of condensed water in the water return pipe, a water seal is realized; the condensed water is not completely discharged during drainage, ensuring the continuous existence of the water seal, thereby preventing the tail gas from being discharged along with the discharge of the condensed water.

Description

Technical Field

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

[0002] During the development, gathering, transportation, storage, and processing of petroleum and natural gas, the gases volatilized, vented, or leaked during wellhead blowout; the gaseous wastes (such as the volatiles of paints and coatings) from the machinery factories and other processing factories affiliated to petroleum and natural gas enterprises; the non-condensable gases, released gases, by-product gases of reactions generated by the production devices of refineries and petrochemical plants, and the waste gases generated during the storage tank area and sewage treatment process; all are petrochemical waste gases rich in various elements generated during the raw material collection, transportation, and product manufacturing processes of petrochemical products.

[0003] For example, a gaseous pollutant called benzo[a]pyrene can induce cancer. It is emitted during the processes such as crude oil refining and fuel combustion, and is easily adsorbed by the floating dust in the atmosphere and enters the human body through respiration, staying in the alveoli and bronchial walls for a long time. Therefore, petrochemical waste gases need to be purified before emission.

[0004] The petrochemical waste gas treatment process usually includes:

[0005] 1. Collection: The waste gas is collected from the production site through pipelines.

[0006] 2. Pretreatment: The solid particles and harmful gases in the waste gas are removed by physical or chemical methods.

[0007] 3. Adsorption: Adsorbents such as activated carbon are used to adsorb the harmful substances in the waste gas.

[0008] 4. Catalysis: The harmful substances adsorbed on the activated carbon are completely decomposed through the action of a catalyst.

[0009] 5. Deep purification: Through technical means such as activated carbon adsorption, desulfurization and denitrification, biological purification, CO, RCO, RTO, etc., the waste gas after catalytic oxidation is deeply purified to remove the residual harmful substances.

[0010] Through the above process, the petrochemical waste gas is treated. Generally speaking, however, the equipment cost of the entire treatment process is relatively high, which many small petroleum product processing factories cannot afford. And many devices are large in size and scattered, making them difficult to install. Moreover, for small and medium-sized enterprises, the waste gas generated by their manufacturing is far from reaching the processing upper limit of common waste gas purification devices such as spray towers and condensation towers. The operation of the equipment will generate some energy costs.

[0011] For some process equipment, such as condensation, many enterprises use spiral condensers to improve the condensation effect by extending the contact time with cold air. However, problems such as how to achieve non-stop external drainage or airtight external drainage after water vapor condensation, and how to prevent the condensate from staying in the pipeline for a long time are faced by many condensation devices.

[0012] Therefore, the present invention provides a petrochemical tail gas recovery system, which improves the condensate recovery structure in the condenser tube during the condensation process to achieve non-stop water collection during condensation and avoid the problem of tail gas leakage as much as possible during drainage. Summary of the Invention

[0013] The purpose of the present invention is to solve the problems existing in the prior art, and a petrochemical tail gas recovery system is proposed.

[0014] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0015] A petrochemical tail gas recovery system includes: a condensation kettle and a refrigeration system that circulates and supplies cold to the condensation kettle. Inside the upper end of the condensation kettle, an intake chamber and an outlet chamber are horizontally spaced. The intake chamber is connected to an intake pipe, and the outlet chamber is connected to an outlet pipe. Inside the condensation kettle, a condensation chamber is provided below the intake chamber and the outlet chamber. The intake chamber is connected to a condenser tube, and the other end of the condenser tube is bent and coiled in the condensation chamber and then communicated with the outlet chamber. The lowest turning part of the condenser tube is heart-shaped, and the bottoms of the two sinking parts of the heart-shaped structure of the condenser tube are both connected to a return pipe. The lower ends of the two return pipes are combined and connected to a valve I. On the inner bottom wall of the condenser tube at the port connected to the return pipe, a damping plate that tilts upward in the gas flow direction is provided.

[0016] The refrigeration system includes a refrigerating machine and a cold storage chamber provided on the refrigerating machine. The cold storage chamber has two air outlet ports and an air inlet port. The two air outlet ports of the cold storage chamber are respectively connected to a first cold air pipe and a second cold air pipe. Both the first cold air pipe and the second cold air pipe are inserted from the upper end part of the condensation chamber, and the inserted ports in the condensation chamber are vertically arranged; the lower end of the condensation chamber is connected to a third return pipe that cooperates with the refrigerating machine.

[0017] Preferably, the undulating height of the upward-tilting end of the damping plate does not exceed half of the inner diameter of the condenser tube.

[0018] Preferably, it further includes a primary filtration unit, which is arranged on the intake pipe and is used to filter large-particle impurities in the tail gas to prevent the large-particle impurities from condensing and settling at the damping plate together with water droplets, resulting in blockage of the pipelines inside the condensation kettle.

[0019] Preferably, the primary filtration unit is a pipeline filter.

[0020] Preferably, it further includes a secondary filtration unit. The secondary filtration unit includes a spiral filter tube, which is connected to the air outlet pipe through a flange structure. A flexible filter sleeve is embedded in the filter tube. Screw barrels are provided at both ends of the filter sleeve. A threaded pipe is screwed into the screw barrel. An air hood for gas to pass through is provided in the threaded pipe. Adsorbents are filled between the two air hoods in the filter sleeve for secondary adsorption and purification of the tail gas. A flange plate that cooperates with the flange structure is screwed onto the outer wall of the screw barrel. A rubber ring is sleeved on the outer pipe wall at the threaded mating part of the flange plate and the screw barrel, and the rubber tube is embedded in the port of the filter tube.

[0021] Preferably, the intake pipe, the outlet pipe, the primary filtration unit, and the secondary filtration unit are all redundantly provided.

[0022] Preferably, a first return air pipe is provided between the two outlet pipes of the condensation kettle.

[0023] Preferably, a second return air pipe is provided between the first return air pipe and the air outlet of the secondary filtration unit.

[0024] Preferably, at least one pressure relief valve is provided on the condensation kettle.

[0025] Preferably, it further includes a frame.

[0026] Compared with the prior art, the present invention provides a petrochemical tail gas recovery system, which has the following beneficial effects:

[0027] 1. Through the vertical impact of two groups of cold air and the guidance of the arc-shaped inner wall of the condensation chamber, a spiral air flow is formed by itself. Cooperating with the spiral cold air pipes, the petrochemical tail gas has more heat exchange area, can make more effective use of the heat exchange effect of the cold air, and improve the condensation effect of the equipment. The cold air circulates, reducing the loss of cold air, and can reduce the working load pressure of the refrigerant. Through the upward structure of the damping plate to guide the tail gas, the backflow of the tail gas into the return water pipe can be avoided, 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 water pipe is used to achieve the water seal effect of the return water pipe. The condensed water is not completely discharged during drainage to ensure 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.

[0028] 2. The spiral design of the filter tube of the present invention can not only achieve the purpose of extending the adsorption channel length, increasing the contact time between the tail gas and the adsorbent, and improving the adsorption effect, but also reduce the occupied space, reduce the space volume of the equipment, and is also convenient for handling.

[0029] 3. The redundant setting of the present invention allows for one to be used as a standby. When a group of pipelines fails or needs to be repaired and replaced, the other group can be operated, enabling the equipment to continue running and achieving non-stop operation.

[0030] 4. The present invention centralizes some petrochemical waste gas treatment processes, reduces the volume of the tail gas recovery system, and shrinks the floor area and the external volume of the equipment.

[0031] Other advantages, objectives, and features of the present invention will, to some extent, be elaborated in the subsequent description; and to some extent, will be obvious to those skilled in the art based on the study of the following text; or can be learned from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a left - hand axonometric schematic diagram of the present invention.

[0033] Figure 2 It is a right - hand axonometric schematic diagram of the present invention.

[0034] Figure 3 It is a rear - view three - dimensional schematic diagram of the present invention.

[0035] Figure 4 It is a front - view schematic diagram of the present invention.

[0036] Figure 5 It is a rear - view schematic diagram of the present invention.

[0037] Figure 6 It is a top - view schematic diagram of the present invention after removing the frame.

[0038] Figure 7 It is a vertical cross - sectional schematic diagram of the condensation kettle and the refrigeration system structure of the present invention.

[0039] Figure 8 It is a horizontal cross - sectional schematic diagram of the first cold air pipe and the second cold air pipe of the present invention located on the side of the condensation cavity.

[0040] Figure 9 It is of the present invention Figure 7 condensation kettle cross - sectional schematic diagram.

[0041] Figure 10 It is a schematic diagram of the heart - shaped structure at the lower end of the condensation pipe of the present invention.

[0042] Figure 11 It is of the present invention Figure 10 partial schematic diagram at location A.

[0043] Figure 12 It is a cross - sectional schematic diagram of the isolation part between the air inlet cavity and the air outlet cavity of the present invention.

[0044] Figure 13 It is a three - dimensional assembly schematic diagram of the filter sleeve of the present invention.

[0045] Figure 14 It is a three - dimensional diagram of the filter sleeve of the present invention and a partially enlarged view of the port screw cylinder.

[0046] Figure 15 The screw barrel assembly and the explosion diagram of the present invention.

[0047] Figure 16 The sectional schematic view of the screw barrel assembly assembled inside the filter tube of the present invention.

[0048] Figure 17 The sectional view of the connection between the flange and the threaded pipe of the present invention.

[0049] Figure 18 The structural schematic view of the return water pipe, the water seal pipe and the drain pipe of the present invention.

[0050] In the figure: 1. Frame; 2. Condensation kettle; 3. Intake cavity; 4. Exhaust cavity; 5. Condensation cavity; 6. Intake pipe; 7. Exhaust pipe; 8. Condensation pipe; 801. Cold-receiving pipe; 802. Water collecting pipe; 803. Return water pipe; 804. Damping plate; 805. Drain pipe; 9. Refrigerator; 10. First cold air pipe; 11. Second cold air pipe; 12. Pressure relief valve; 13. Third return air pipe; 14. First-stage filtration unit; 15. Second-stage filtration unit; 1501. Filter tube; 1502. Filter sleeve; 1503. Screw barrel; 1504. Threaded pipe; 1505. Air hood; 1506. Handle; 1507. Flange; 1508. First flange; 1509. Second flange; 15010. Rubber ring; 16. First return air pipe; 17. Second return air pipe; 18. Exhaust pipe; 19. Water seal pipe. Specific embodiments

[0051] Next, in combination with the attached drawings in the embodiments of the present invention Figures 1 - 18 The technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0052] Embodiment 1. In order to solve the problems in the prior art such as how to achieve non-stop or airtight external discharge after water vapor condensation, and how to prevent condensation from staying in the pipeline for a long time, this embodiment provides a petrochemical tail gas recovery system, including: a condensation kettle 2 and a refrigeration system for circulating cooling to the condensation kettle 2. Inside the upper end of the condensation kettle 2, an intake cavity 3 and an exhaust cavity 4 are horizontally arranged at intervals. The intake cavity 3 is connected with an intake pipe 6, and the exhaust cavity 4 is connected with an exhaust pipe 7. Inside the condensation kettle 2, a condensation cavity 5 is arranged below the intake cavity 3 and the exhaust cavity 4. The intake cavity 3 is connected with a condensation pipe 8. The other end of the condensation pipe 8 winds and turns in the condensation cavity 5 and then communicates with the exhaust cavity 4. The lowest turning part of the condensation pipe 8 is heart-shaped. The bottoms of the two sunken parts of the heart-shaped structure of the condensation pipe 8 are both connected with a return water pipe 803. The lower ends of the two return water pipes 803 are combined and connected with a first valve. On the inner bottom wall of the condensation pipe 8 at the port connected with the return water pipe 803, a damping plate 804 that tilts upward in the gas flow direction is arranged;

[0053] The refrigeration system includes a refrigerator 9 and a cold storage chamber provided 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 first cold air pipe 10 and a second cold air pipe 11 through a two-way valve. Both the first cold air pipe 10 and the second cold air pipe 11 are inserted into the upper end part of the condensation chamber 5, and the ports inserted into the condensation chamber 5 are vertically arranged. The lower end of the condensation chamber 5 is connected to a third return air pipe 13 that cooperates with the refrigerator 9.

[0054] Details of the principle of this embodiment:

[0055] A petrochemical tail gas recovery system includes:

[0056] (1) A condensation kettle 2. The condensation kettle 2 includes an upper kettle body and a lower kettle body. Both the upper kettle body and the lower kettle body are hollow structures, forming a space for gas flow and cold air flow. Heat insulation layers are provided on the side walls of both the upper kettle body and the lower kettle body to prevent 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 an embedding groove. The upper end of the lower kettle body is embedded in the embedding groove and fixedly installed through bolts to achieve a firm connection between the upper kettle body and the lower kettle body. A first sealing gasket is provided between the embedding groove of the upper kettle body and the upper end surface of the lower kettle body to prevent the condensation kettle 2 from leaking. The split setting of the condensation kettle 2, which is not integrated, after removal, the interiors of the upper kettle body and the lower kettle body are exposed to provide a laying channel for internal pipelines and also enable the repair and replacement of internal equipment.

[0057] A partition is fixedly installed in the middle of the upper kettle body. 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 a second valve. 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 a third valve.

[0058] The hollow chamber in the lower kettle body is a condensation chamber 5. A sealing plate is provided at the upper port of the condensation chamber 5 to isolate the air inlet chamber 3 and the air outlet chamber 4 inside the upper kettle body from the condensation chamber 5 of the lower kettle body. Embedding holes are provided in the sealing plate in both the air inlet chamber 3 and the air outlet chamber 4. A condensation pipe 8 is embedded in the embedding hole in the air inlet chamber 3, and the other port of the condensation pipe 8 passes through the embedding hole at the air outlet chamber 4 and penetrates into the air outlet chamber 4.

[0059] The condenser tube 8 is divided into two parts: one is the cold-receiving tube 801 connected to two insertion holes, and the cold-receiving tube 801 is spirally wound from top to bottom; the other part is the water-collecting tube 802 that communicates with the bottoms of the two cold-receiving tubes 801 together. The water-collecting tube 802 is in the shape of an inverted heart, and the bottoms of the two sunken parts of the water-collecting tube 802 are both connected with a return water pipe 803. The lower ends of the two return water pipes 803 are joined together and are connected with a drain pipe 805 through a first valve. The drain pipe 805 passes through the condensation kettle 2, and the drain pipe 805 is connected with a condensate water recovery tank (not shown in the drawing) placed outside the condensation kettle 2 through a water pump. Two damping plates 804 are provided on the inner bottom wall of the water-collecting tube 802. The damping plates 804 are arranged at the ports of the communicating parts of the return water pipe 803 and the water-collecting tube 802 facing the air inlet direction, and the damping plates 804 are upturned towards the gas flow direction.

[0060] (2) A refrigeration system for circulating cold supply to the condensation chamber 5. The refrigeration system includes a refrigerating machine 9 and a cold storage chamber provided on the refrigerating machine 9. The structure of the refrigeration system shown in the drawing is only a schematic diagram.

[0061] The refrigerating machine 9 is a gas compression refrigerating machine 9, which is composed of a compressor, a condenser, an evaporator, an expander, etc.

[0062] The cold storage chamber is provided with two air outlet ports and an air inlet port. Both air outlet ports of the cold storage chamber are connected with pump machines, and the air outlet ports of the two pump machines are respectively connected with a first cold air pipe 10 and a second cold air pipe 11. The other ends of the first cold air pipe 10 and the second cold air pipe 11 are both inserted into the condensation chamber 5, and the insertion parts are located at the upper end part of the condensation chamber 5. The air outlet end of the first cold air pipe 10 is horizontally and vertically inserted into the condensation chamber 5, and the air outlet end of the second cold air pipe 11 is bent above the condensation kettle 2 and passes through the partition plate and is inserted into the condensation chamber 5 from the upper end of the condensation chamber 5. The air outlet end of the first cold air pipe 10 is located below the air outlet end of the second cold air pipe 11, and the positional relationship between the ports of the first cold air pipe 10 and the second cold air pipe 11 inserted into the condensation chamber 5 is close to the top wall of the condensation chamber 5 and is vertically arranged. The lower end of the condensation chamber 5 is connected with a third return air pipe 13, and the other end of the third return air pipe 13 is communicated with the air inlet of the compressor.

[0063] According to the above technical solution:

[0064] 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 tube 8 and flows along the condenser tube 8 to the air outlet chamber 4, and finally is discharged outside the condensation kettle 2 from the air outlet chamber 4.

[0065] The gas compressed by the compressor is first cooled in the condenser and releases 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 both decrease. When the gas expands in the expander, it does work externally and becomes part of the input work of the compressor.

[0066] The expanded low-temperature gas enters the cold storage chamber, and then is sucked into the two-way valve by the pump 1, and then input into the cold air pipe 1 10 and the cold air pipe 2 11. The cold air pipe 1 10 and the cold air pipe 2 11 vertically blow into the condensation chamber 5, impact on the condensation pipe 8, and absorb the heat of the petrochemical tail gas in the condensation pipe 8, thus achieving the purpose of refrigeration.

[0067] The cold air blown into the condensation chamber 5 by the cold air pipe 1 10 and the cold air pipe 2 11 vertically impacts, thus forming a spiral flow from top to bottom. The spiral-flowing cold air has more heat exchange area compared with the traditional straight-tube condenser. When the tail gas flows in the cold tube 801, it can exchange heat with the cold air more fully, thereby increasing the heat transfer efficiency. The cold tubes 801 in the upper part of the condensation pipe 8 are also spirally arranged, increasing the residence time of the petrochemical tail gas in the condensation chamber 5, that is, increasing the heat exchange duration. Moreover, the spiral structure enables the tail gas to flow in the low-temperature environment for a longer time and have a longer heat exchange time with the petrochemical tail gas in the condensation pipe 8, and can make more effective use of the heat exchange effect of the cold air. And in the spiral pipeline, the tail gas is affected by centrifugal force and centripetal force, generating secondary flow and eddy current phenomena, enabling the heat exchange between the inner and outer parts of the tail gas and the pipe wall, and further improving the heat transfer efficiency. With the multi-phase cooperation, the condensation effect is improved to increase the removal rate of water vapor in the petrochemical tail gas. After that, the gas returns to the compressor from the return air pipe 3 13, exchanges heat with the compressed gas, and then enters the compressor again to be compressed. The cold air circulation can improve the utilization rate and reduce the load pressure of the refrigerator 9 for continuous refrigeration.

[0068] The condensed water vapor first flows along the wall in the condensation pipe 8, and then accumulates in the sinking part of the water collecting pipe 802. A part of the deposited condensate waits to flow into the return water pipe 803 after overflowing the damping plate 804; another part flows directly into the return water pipe 803 along the damping plate 804 under the impact pressure of the petrochemical tail gas flowing in the pipe. The condensed water accumulates in the return water pipe 803, and the discharge of the condensed water is controlled by the opening and closing of the valve 1, thus completing the collection and discharge of the condensed water.

[0069] Through the above scheme, not only can the condensation effect of the equipment be improved and the working load pressure of the refrigerator 9 be reduced; but also through the structural cooperation of the damping plate 804, the flow of the tail gas is guided to reduce the accumulation of the tail gas in the return water pipe 803; at the same time, the water seal of the return water pipe 803 is realized by using the condensed water itself to reduce the tail gas leakage amount during drainage.

[0070] In summary, in this solution, through the vertical impact of two groups of cold air and the guidance of the arc-shaped inner wall of the condensation chamber 5, a spiral air flow is formed automatically. In cooperation with the spiral cold air pipe 801, the petrochemical tail gas has a larger heat exchange area, can make more effective use of the heat exchange effect of the cold air, and improve the condensation effect of the equipment. The cold air circulates, reducing cold air loss, and can reduce the working load pressure of the refrigerant. Through the upward structure of the damping plate 804 to guide the tail gas, the tail gas is prevented from flowing back into the return water pipe 803, reducing the retention of the tail gas with the condensed water. At the same time, by using the accumulation of the condensed water itself in the return water pipe 803, the water seal effect of the return water pipe 803 is achieved, and it is not completely drained during drainage to ensure the continuous existence of the water seal, thereby preventing a small amount of retained tail gas from being discharged with the condensed water.

[0071] In this embodiment, the output power of the pump corresponding to the first cold air pipe 10 is greater than the output power of the pump corresponding to the second cold air pipe 11, so that the impact force of the cold air blown horizontally into the condensation chamber 5 is greater than the impact force of the cold air blown vertically into the condensation chamber 5, so as to ensure that the two-phase cold air impacts and mixes and then impacts on the inner wall of the condensation chamber 5, and diffuses under the guidance of the chamber wall. And due to the vertical impact of the second cold air pipe 11, a spiral air flow is formed. Preferably, a spiral drainage plate can be arranged at the position facing the air outlet end of the condenser pipe in the condensation chamber 5 to guide the air flow impact through the drainage plate to form a spiral air flow. Or as shown in the attached Figure 8 figure, the insertion positions of the first cold air pipe 10 and the second cold air pipe 11 are on the side of the condensation chamber 5, directly impacting on the arc-shaped inner wall of the condensation chamber 5 to guide the cold air flow.

[0072] In this embodiment, the damping plate 804 is upturned in the direction of gas flow, so as to play a guiding role for the gas. When the gas is flowing, it continuously receives the air pressure impact from the rear, so it will not flow back into the return water pipe 803 along the damping plate 804, reducing the accumulation of the tail gas in the return water pipe 803. At the same time, when the condensed water is discharged, after the first valve is closed, there is still a part of condensed water in the return water pipe 803. The water seal of the return water pipe 803 is realized through the condensed water in the return water pipe 803, thereby reducing the leakage amount of the petrochemical tail gas after the first valve is opened.

[0073] In this embodiment, shaft seals are provided between the first cold air pipe 10, the second cold air pipe 11, the air inlet pipe 6, the air outlet pipe 7, the drain pipe 805, the third return air pipe 13 and the condensation kettle 2 to achieve pipeline installation sealing to prevent the leakage of tail gas and cold air.

[0074] In this embodiment, a heat insulation layer is also provided on the sealing plate to prevent the water vapor in the tail gas from condensing in the air inlet chamber 3 and increasing the subsequent cleaning difficulty.

[0075] In this embodiment, the horizontal projection of the damping plate 804 shields the communicating part between the return water pipe 803 and the water collecting pipe 802 to prevent the tail gas from flowing back into the return water 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 condensation pipe 8, so as to prevent the condensed water from closing the pipe orifice when it accumulates at the sunken part of the water collecting pipe 802 below the condensation pipe 8, which may affect the flow of the tail gas.

[0076] In this embodiment, since both ends of the filter pipe 1501 penetrate into the intake cavity 3 and the outlet cavity 4 respectively, multiple groups of filter pipes 1501 can be provided to achieve multi-pipeline condensation, with higher efficiency.

[0077] In this embodiment, it further includes a frame 1, which provides an installation basis for each device. For example, it provides an installation base surface for the condensation kettle 2 and the refrigeration system, and provides bracket supports for pipelines such as the intake pipe 6 and the outlet pipe 7.

[0078] Embodiment 2, in a further embodiment of this solution, it further includes a primary filtration unit 14, which is arranged on the intake pipe 6. The primary filtration unit 14 is a pipeline filter, and a filter element is provided inside. The large-particle impurities in the tail gas are filtered by the filter element to prevent the large-particle impurities from condensing and settling at the damping plate 804 together with the water droplets, which may cause blockage of the pipelines in the condensation kettle 2.

[0079] It further includes a secondary filtration unit 15 for adsorptive filtration of the condensed tail gas. The secondary filtration unit 15 includes a spiral filter pipe 1501. The intake port of the filter pipe 1501 is butted against the outlet pipe 7 of the outlet cavity 4, and an external exhaust pipe 18 is butted against the outlet port of the filter pipe 1501. The tail gas after passing through the filter pipe 1501 is transferred to the next process through the exhaust pipe 18. Flange one 1508 is provided at both the intake port and the outlet port of the filter pipe 1501, and flange two 1509 is provided at both the outlet port of the outlet pipe 7 and the intake port of the exhaust pipe 18. Flange one 1508 and flange two 1509 are fastened and connected by bolts to achieve the detachable connection between the filter pipe 1501 and the outlet pipe 7 for receiving and transporting the condensed tail gas. And a gasket two is clamped between flange one 1508 and flange two 1509 to enhance the sealing performance.

[0080] A flexible filter sleeve 1502 is embedded in the filter tube 1501, and the filter sleeve 1502 can be bent and deformed along with the spiral shape of the filter tube 1501. Screw cylinders 1503 are provided at both ends of the filter sleeve 1502, and threaded tubes 1504 are screwed into the internal threads of the screw cylinders 1503. An air hood 1505 for gas to pass through and a handle 1506 for pulling are provided inside the threaded tube 1504. Adsorbents are filled between the two air hoods 1505 inside the filter sleeve 1502 for secondary adsorption and purification of the tail gas. A flange plate 1507 that cooperates with the flange structure is screwed onto the outer wall thread of the screw cylinder 1503. A rubber ring 15010 is sleeved on the outer pipe wall of the threaded part where the flange plate 1507 and the screw cylinder 1503 are threadedly engaged, and the rubber tube is embedded in the port of the filter tube 1501.

[0081] Through the above technical solutions:

[0082] During installation, hold the handle 1506 and screw the threaded tube 1504 into the screw cylinder 1503 at any end of the filter sleeve 1502 to block one end of the filter sleeve 1502 through the air hood 1505; then fill the adsorbents into the filter sleeve 1502; then screw the threaded tube 1504 at the other end into the corresponding screw cylinder 1503; intercept the adsorbents in the filter sleeve 1502 through the two air hoods 1505 to complete the assembly of the filtering structure. Then screw a flange plate 1507 onto the screw cylinder 1503, vertically place the filter tube 1501, and then insert the screw cylinder 1503 without the screwed flange plate 1507 into the filter tube 1501 and gradually feed 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 large, when installing the filter sleeve 1502, a 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 can be pulled through the filter tube 1501 by pulling. The specific operation depends on the on-site actual operation), and insert the installed flange plate 1507 into the inlet of the filter tube 1501, and the flange of the flange plate 1507 abuts against the flange one 1508 at the inlet of the filter tube 1501; then screw another flange plate 1507 onto the other screw cylinder 1503 of the filter sleeve 1502 and insert this flange plate 1507 into the outlet of the filter tube 1501, and the flange of the flange plate 1507 abuts against the flange one 1508 at the outlet of the filter tube 1501 to realize the embedding of the filter sleeve 1502 in the filter tube 1501, and limit the filter sleeve 1502 through the flange plates 1507 at both ends to prevent the filter sleeve 1502 from shifting and twisting under the impact of the tail gas; and also seal the gap between the flange plate 1507 and the filter tube 1501 through the rubber ring 15010 provided outside the flange plate 1507, so that the tail gas can only pass through the flange at the pipe connection, avoiding the leakage of the tail gas from the gap. Then butt the flange one 1508 at both ends of the filter tube 1501 with the flange two 1509 on the air outlet pipe 7 and the exhaust pipe 18 respectively and fasten them with bolts to realize the installation of the filter tube 1501.

[0083] During disassembly and assembly, first unscrew the bolts, remove the filter tube 1501, and then unscrew the flange 1507 from the screw cylinder 1503. Then, the filter sleeve 1502 can be pulled out from the filter tube 1501 to complete the disassembly of the filter sleeve 1502. After that, unscrew the threaded pipe 1504 on the screw cylinders 1503 at both ends, and the adsorbent in the filter sleeve 1502 can be poured out. New adsorbent can be replaced, or the adsorbent can be desorbed and regenerated for recycling (thermal desorption, using nitrogen as the carrier to carry heat to heat the adsorbent to make the adsorbed substances desorb. Nitrogen is an inert gas that can protect the safety of the adsorbent at high temperatures).

[0084] In summary, through the spiral design of the filter tube 1501, it can not only achieve the purpose of extending the adsorption channel length, increasing the contact time between the tail gas and the adsorbent, and improving the adsorption effect, but also reduce the occupied space, shrink the equipment space volume, and facilitate handling.

[0085] In this solution, the outer diameters of the threaded pipe 1504 and the screw cylinder 1503 are both smaller than the inner diameter of the filter tube 1501, forming a movable space for easy installation and movement inside the spirally bent filter tube 1501.

[0086] In this embodiment, the filter sleeve 1502 is made of plastic synthetic fiber or polyurethane film and is airtight. This can prevent the tail gas inside 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 passing through the adsorbent filtration.

[0087] In this embodiment, by screwing the threaded pipe 1504 into the screw cylinder 1503, the air hoods 1505 on the threaded pipe 1504 are used to seal both ends of the filter sleeve 1502, rather than directly setting the air hoods 1505 at the ports of the flange 1507. The purpose is that when the threaded pipe 1504 is screwed into the screw cylinder 1503, it does not occupy the external volume, and it can not only achieve the sealing of both ends of the filter sleeve 1502, but also not affect the traction and installation of the filter sleeve 1502 filled with adsorbent inside the filter tube 1501.

[0088] In this embodiment, the diameter of the filter tube 1501 is less than half of the diameter of the outlet pipe 7 (the figure shown in the drawing is only a schematic diagram, and the dimensions are subject to the text description). In this way, through the reduction of the pipe diameter, the pressure of the tail gas filled into the filter tube 1501 is increased. The increase in pressure can also increase the adsorption amount of the adsorbent substance, extend the time for the adsorbent to reach the adsorption saturation amount, that is, increase the single - use duration of the adsorbent, and reduce the disassembly and replacement frequency.

[0089] In this embodiment, the adsorbent is activated carbon fiber (ACF). The activated carbon fiber is fibrous, and after high-temperature activation, the fiber surface is covered with micropores (i.e., the positions occupied by hydrogen and oxygen atoms before volatilization). The fiber diameter of the activated carbon fiber is 5-20 μm, the specific surface area is on average 1000-1500 m² / g, the average pore diameter is 1.0-4.0 nm, and the micropores are evenly distributed on the fiber surface. The organic substances that activated carbon fiber can adsorb include: hydrocarbons (benzene, toluene, xylene, trimethylbenzene, n-hexane, cyclohexane, etc.), halogenated hydrocarbons (chloromethane, dichloromethane, trichloromethane, trichloroethylene, trichloroethane, bromomethane, carbon 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.). It is used for air purification and can effectively remove various harmful and odorous substances in the tail gas, especially carcinogenic substances and aromatic compounds (such as benzene and aldehydes). Compared with activated carbon, the micropore diameter of activated carbon fiber is small and uniform, the structure is simple, and the specific surface area is large. Therefore, activated carbon fiber has a faster adsorption rate and a higher adsorption rate for adsorbing small molecule substances, and it is also easy to desorb.

[0090] In this embodiment, a filter cloth made of non-woven fabric is provided in the middle of the filter sleeve 1502. The filter sleeve 1502 is divided into two installation cavities by the filter cloth. Labels 1# and 2# are engraved at the inlets and outlets of the two groups of screw cylinders 1503 respectively. 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#. So that the adsorption capacity of the adsorbent corresponding to the inlet direction of the filter sleeve 1502 is less than the adsorption capacity of the adsorbent in the direction of the outlet of the filter sleeve 1502. When all the adsorbents have the same grade, after injecting the tail gas, the tail gas is first concentrated at the inlet and adsorbed and purified, so that the adsorption amount of the adsorbent at the inlet reaches saturation first, which may cause the clogging of the coarse pores for the adsorbate molecules to pass through on the adsorbent, affecting the subsequent transportation of the tail gas, and making the adsorbent at the back may need to be replaced in advance before reaching saturation. By setting the two installation cavities in different grades, the saturation time of the adsorption amount of the front adsorbent is prolonged, and the time difference from the saturation time of the back adsorbent 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 service life is prolonged. (For example, when the adsorbent is granular activated carbon, the fine pore diameter of the granular activated carbon in the 1# installation cavity is 5-10 nm, and the fine pore diameter of the granular activated carbon in the 2# installation cavity is 0-5 nm. When it is activated carbon fiber, the micropore diameter of the activated carbon fiber in the 2# installation cavity is also smaller than that in the 1# installation cavity).

[0091] Embodiment 3. In a further embodiment of the present solution, the intake pipe 6, the outlet pipe 7, the primary filtration unit 14, and the secondary filtration unit 15 are all redundantly provided, and stop valves are provided at the connected pipe ports. That is, there are two intake pipes 6 and two outlet pipes 7. Both of the two intake pipes 6 are connected to the primary filtration unit 14, and both of the two outlet pipes 7 are connected to the secondary filtration unit 15. In this way, one can be used as a standby. When a group of pipelines fails or needs to be repaired and replaced, the other group can be operated, enabling the equipment to continue running and achieving non-stop operation.

[0092] In this embodiment, a first return pipe 16 is provided between the two outlet pipes 7 of the condensation kettle 2. The first return pipe 16 is connected to the two outlet pipes 7 through a reversing valve, which can achieve fluid commutation. A channel is established between the two outlet pipes 7 through the first return pipe 16. During normal operation, on the reversing valve, the connection ports between the first return pipe 16 and the outlet pipe 7 are closed, and the channel between the outlet pipe 7 and the filter pipe 1501 is unblocked. When there is a leak or an emergency damage in the pipeline, valve or other structures between a group of outlet pipes 7 and the secondary filtration unit 15, or on the secondary filtration unit 15, or when the stop valve between the outlet pipe 7 and the air outlet cavity 4 leaks, a temporary bypass channel can be formed through the first 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 bypassed between the outlet pipe 7 and the corresponding equipment through the first return pipe 16 to improve the operating safety of the equipment.

[0093] In this embodiment, a second return pipe 17 is provided between the first return pipe 16 and the air outlet of a certain secondary filtration unit 15. For example, a second return pipe 17 is connected between the air outlet of the 1# filter pipe 1501 in the secondary filtration unit 15 corresponding to the 1# outlet pipe 7 and the outlet pipe 7 one. A reversing valve is also provided between the second return pipe 17, the first return pipe 16, and the air outlet of the filter pipe 1501. A tail gas transportation channel of the outlet pipe 7, the 1# secondary filtration unit 15, the second return pipe 17, the first return pipe 16, the 2# secondary filtration unit 15, and the exhaust pipe 18 can be additionally formed, enabling the tail gas to pass through two series-connected secondary filtration units 15 for adsorption and filtration, which can handle the situation where the concentration of harmful substances in the tail gas is relatively high or the filtration accuracy requirements are relatively high, so as to improve the filtration accuracy and filtration effect.

[0094] In this solution, at least one pressure relief valve 12 is provided on the condensation kettle 2. For example, pressure relief valves 12 are provided in the intake cavity 3, the air outlet cavity 4, and the condensation cavity 5, which are used to balance and regulate the air pressure to avoid problems such as equipment and pipeline bursting due to excessive pressure.

[0095] In this solution, the lower ports of the two groups of return water pipes 803 communicate with each other to form a U-shaped pipe. There is a pipeline interface at the sunken bottom of the communicating part of the U-shaped pipe, and the pipeline interface is connected to the first valve. The opening and closing of the sunken part of the U-shaped pipeline are controlled by the first valve, and then the discharge of the condensed water in the return water pipe 803 into the drain pipe 805 is controlled. In order to always ensure the water seal effect in the return water pipe 803, a side-placed S-shaped water seal pipe 19 can also be butted at the pipeline interface. The water seal pipe 19 is then butted with the drain pipe 805 through the first valve. Through the curved design of the water seal pipe 19, it is ensured that there is always accumulated water in the water seal pipe 19, so that the continuous existence of the water seal can be ensured without controlling the drainage volume of the drain pipe 805, reducing the drainage requirements. An emptying valve is provided on the side wall of the sunken pipeline of the water seal pipe 19. During cleaning, the condensed water accumulated in the water seal pipe is drained through the emptying valve to avoid the generation of peculiar smell due to the long-term accumulation of condensed water.

[0096] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

[0097] In the description of this specification, the description with reference to terms such as "an embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection 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 can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0098] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A petrochemical tail gas recovery system, characterized in that, Comprising: A condensation kettle (2) and a refrigeration system for circulating and supplying cold to the condensation kettle (2). Inside the upper end of the condensation kettle (2), an air inlet chamber (3) and an air outlet chamber (4) are horizontally spaced. 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). Inside the condensation kettle ( ), a condensation chamber (5) is provided below the air inlet chamber (3) and the air outlet chamber (4). The air inlet chamber (3) is connected to a condensation pipe (8). The other end of the condensation pipe (8) is bent and coiled in the condensation chamber (5) and then communicated with the air outlet chamber (4). The lowermost turning part of the condensation pipe (8) is heart-shaped. At the bottom ends of the two sunken parts of the heart-shaped structure of the condensation pipe (8), a water return pipe (803) is connected to each. The lower ends of the two water return pipes (803) are combined and connected with a first valve. On the inner bottom wall of the condensation pipe (8) at the port connected to the water return pipe (803), a damping plate (804) that tilts upward in the gas flow direction is provided; The refrigeration system includes a refrigerating machine (9) and a cold storage chamber provided on the refrigerating machine (9). The cold storage chamber has two air outlet ports and an air inlet port. The two air outlet ports of the cold storage chamber are respectively connected to a first cold air pipe (10) and a second cold air pipe (11). Both the first cold air pipe (10) and the second cold air pipe (11) are inserted from the upper end part of the condensation chamber (5), and the inserted ports in the condensation chamber (5) are vertically arranged; The lower end of the condensation chamber (5) is connected to a third water return pipe (13) that cooperates with the refrigerating machine (9); It further includes a secondary filtration unit (15). The secondary filtration unit (15) includes a spiral filter pipe (1501). The filter pipe (1) is connected to the air outlet pipe (7) through a flange structure. A flexible filter sleeve (1502) is embedded in the filter pipe (1501). At both ends of the filter sleeve (1502), a screw cylinder (1503) is provided. A threaded pipe (1504) is screwed into the screw cylinder (1503). An air hood (1505) for gas to pass through is provided in the threaded pipe (1504). Adsorbents are filled between the two air hoods (1505) in the filter sleeve (1502) for secondary adsorption and purification of the tail gas; A flange plate (1507) that cooperates with the flange structure is screwed onto the outer wall of the screw cylinder (1503). A rubber ring (15010) is sleeved on the outer pipe wall at the threaded cooperation part of the flange plate (1507) and the screw cylinder (1503). The rubber pipe is embedded in the port of the filter pipe (1501).

2. The petrochemical tail gas recovery system according to claim 1, characterized in that, The undulating height of the upward-tilting end of the damping plate (804) does not exceed half of the inner diameter of the condensation pipe (8).

3. The petrochemical tail gas recovery system according to claim 1, wherein, It further includes a primary filtration unit (14) provided on the air inlet pipe (6) for filtering large-particle impurities in the tail gas to prevent the large-particle impurities from condensing and settling with water droplets at the damping plate (804) and causing blockage of the pipelines inside the condensation kettle (2).

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

5. A petrochemical tail gas recovery system according to any one of claims 1-4, characterized in that, The air inlet pipe (6), the air outlet pipe (7), the primary filtration unit (14), and the secondary filtration unit (15) are all redundantly provided.

6. A petrochemical tail gas recovery system according to claim 5, characterized in that, A first water return pipe (16) is provided between the two air outlet pipes (7) of the condensation kettle (2).

7. A petrochemical tail gas recovery system according to claim 6, characterized in that, A second water return pipe (17) is provided between the first water return pipe (16) and the air outlet of the secondary filtration unit (15).

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

9. The petrochemical tail gas recovery system according to claim 3, characterized in that, It further includes a frame (1).

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