A recovery system for silicone by-product high-boilers

Abstract

The utility model discloses a kind of recovery system of organic silicon by-product high-boiling substance, it includes wet dust removal tower and reboiler, the liquid outlet of wet dust removal tower is communicated with the liquid inlet of reboiler, the gas outlet of reboiler is communicated with the gas inlet of wet dust removal tower;It further includes flash tank, high-boiling scrubbing tower, flash condenser, recovery tank and separation tower;The liquid outlet of reboiler is communicated with the liquid inlet of flash tank, the gas outlet of flash tank is communicated with the gas inlet of high-boiling scrubbing tower, the liquid outlet of high-boiling scrubbing tower is communicated with the liquid inlet of flash tank, the gas outlet of high-boiling scrubbing tower is communicated with the gas inlet of flash condenser, the liquid outlet of flash condenser is communicated with the liquid inlet of recovery tank, the liquid outlet of recovery tank is respectively communicated with the washing inlet of high-boiling scrubbing tower and the liquid inlet of separation tower.Welfare effect: the utility model simple connection relationship, easily realized, the effective recycling of high-boiling substance is realized, and the influence to environment and security risk are reduced.

Description

Technical Field

[0001] This utility model relates to the technical field of treating high-boiling-point substances by-products of organosilicon, and in particular to a recovery system for high-boiling-point substances by-products of organosilicon. Background Technology

[0002] In the direct synthesis of organosilicon monomers, which is currently widely used both domestically and internationally, in addition to the target product dimethyldichlorosilane, some byproducts also occur, including methyltrichlorosilane, trimethylchlorosilane, methyldichlorosilane, high-boiling-point substances, and low-boiling-point substances. High-boiling-point substances refer to the portion of the crude monomer product with a boiling point exceeding 80℃. Currently, the mass fraction of high-boiling-point substances in the crude product is approximately 7% to 8%. After dust removal and distillation, the crude monomer product yields high-purity dimethyldichlorosilane. To improve raw material utilization, manufacturers often pressurize and re-feed unreacted catalysts collected by dust removal devices (cyclone separators) into a fluidized bed for further reaction. The syngas exiting the cyclone separator still contains fine dust, crude monomer, and high-boiling-point substances (HB). A wet scrubbing tower is used to wash and remove the methylchlorosilane monomer, thus removing solid particles and high-boiling-point substances from the methylchlorosilane syngas. The dust-laden chlorosilane mixture is heated in a reboiler, and the gas phase is discharged from the top of the wet scrubbing tower and then undergoes multi-stage condensation in the top condenser. After condensation, part of the condensate is refluxed for washing and dust removal, and part is recovered and sent to subsequent distillation processes. The slurry residue from the reboiler is disposed of externally. Because the residue contains high-boiling-point substances, it is a mixed liquid with an irritating odor and strong corrosiveness, with a density of approximately 1.13 g·cm³ at room temperature and pressure. 3 With a boiling range of 80~215℃, it contains more than 30 compounds. If it is not processed and recycled in a timely manner, the subsequent processing will be much more difficult. Moreover, high-boiling-point substances can be used to produce silicone waterproofing agents, silicone oils, silicone resins, defoamers, and release agents. Failure to recycle them will not only cause serious environmental problems and safety hazards, but also result in a large waste of valuable resources. Utility Model Content

[0003] The main objective of this invention is to provide a system for recovering high-boiling-point substances from organosilicon byproducts, which enables the effective recovery and utilization of these substances while reducing their environmental impact and safety hazards.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a system for recovering high-boiling-point substances from organosilicon byproducts, comprising a wet scrubbing tower and a reboiler, wherein the liquid outlet of the wet scrubbing tower is connected to the liquid inlet of the reboiler, and the gas outlet of the reboiler is connected to the gas inlet of the wet scrubbing tower; the system further comprises a flash tank, a high-boiling-point scrubbing tower, a flash condenser, a recovery tank, and a separation tower; the liquid outlet of the reboiler is connected to the liquid inlet of the flash tank, the gas outlet of the flash tank is connected to the gas inlet of the high-boiling-point scrubbing tower, the liquid outlet of the high-boiling-point scrubbing tower is connected to the liquid inlet of the flash tank, the gas outlet of the high-boiling-point scrubbing tower is connected to the gas inlet of the flash condenser, the liquid outlet of the flash condenser is connected to the liquid inlet of the recovery tank, and the liquid outlet of the recovery tank is connected to both the scrubbing inlet of the high-boiling-point scrubbing tower and the liquid inlet of the separation tower.

[0005] Furthermore, it also includes a tail gas scrubbing tower, a high-boiling-point scrubbing liquid buffer tank, a tail gas condenser, a gas-liquid separator, and a directional conversion device; the outlet of the flash condenser is connected to the inlet of the tail gas scrubbing tower, the outlet of the high-boiling-point scrubbing liquid buffer tank is connected to the inlet of the tail gas scrubbing tower, the outlet of the tail gas scrubbing tower is connected to the inlet of the tail gas condenser, the outlet of the tail gas condenser is connected to the inlet of the high-boiling-point scrubbing liquid buffer tank, the outlet of the tail gas condenser is connected to the inlet of the gas-liquid separator, and the outlet of the gas-liquid separator is connected to the inlet of the directional conversion device.

[0006] Furthermore, it also includes a top condenser, a reflux tank, a top-source buffer tank, a side cooler, a side-source buffer tank, a bottom cooler, and a bottom buffer tank; the top outlet of the separation tower is connected to the inlet of the top condenser, the liquid outlet of the top condenser is connected to the inlet of the reflux tank, and the liquid outlet of the reflux tank is connected to both the reflux outlet of the separation tower and the inlet of the top-source buffer tank; the side outlet of the separation tower is connected to the inlet of the side cooler, and the liquid outlet of the side cooler is connected to the inlet of the side-source buffer tank; the bottom outlet of the separation tower is connected to the inlet of the bottom cooler, and the liquid outlet of the bottom cooler is connected to the inlet of the bottom buffer tank.

[0007] Furthermore, the outlet of the condenser at the top of the tower is connected to the inlet of the tail gas scrubbing tower.

[0008] Furthermore, a level sensor is installed in the reboiler, and a solenoid valve is installed on the pipeline between the reboiler and the flash tank; the outlet of the recovery tank is connected to the inlet of the tail gas scrubbing tower, a pressure sensor is installed in the recovery tank, and a pressure relief valve is installed on the pipeline between the recovery tank and the tail gas scrubbing tower; the signal output terminals of the level sensor and the pressure sensor are both connected to the signal input terminal of the controller via signal connection, and the signal output terminal of the controller is connected to the signal input terminals of the solenoid valve and the pressure relief valve via signal connection.

[0009] This invention has the following advantages: The connection relationship of this invention is simple and easy to implement. The slurry discharged from the reboiler is flash-evaporated through a flash tank, and then washed to remove impurities through a high-boiling-point washing tower. After that, it is condensed through a flash condenser. The condensed liquid is then subjected to high-boiling-point distillation through a separation tower. The high-boiling-point substances distilled out are used to produce hydrogen-containing silicone oil and as raw materials for high-boiling-point cracking, respectively. This achieves effective recycling of high-boiling-point substances and reduces the impact on the environment and safety hazards. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the overall structure of a system for recovering high-boiling-point substances from organosilicon byproducts according to this utility model.

[0012] In the diagram: 1. Wet dust removal tower; 2. Reboiler; 3. Flash tank; 4. High-boiling-point scrubbing tower; 5. Flash condenser; 6. Recovery tank; 7. Separation tower; 8. Tail gas scrubbing tower; 9. High-boiling-point scrubbing liquid buffer tank; 10. Tail gas condenser; 11. Gas-liquid separator; 12. Directional conversion device; 13. Top condenser; 14. Reflux tank; 15. Top extraction buffer tank; 16. Side cooler; 17. Side extraction buffer tank; 18. Bottom cooler; 19. Bottom buffer tank; 20. Level sensor; 21. Solenoid valve; 22. Pressure sensor; 23. Pressure relief valve; 24. Controller. Detailed Implementation

[0013] The following is in conjunction with the appendix Figure 1 The principles and features of this utility model are described, making the technical means, creative features, and achieved objectives of this utility model easy to understand, and further elaborating on this utility model.

[0014] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0015] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0016] like Figure 1 As shown, the technical solution adopted by this utility model is as follows: a recovery system for high-boiling-point substances from organosilicon byproducts, comprising a wet scrubbing tower 1, a reboiler 2, a flash tank 3, a high-boiling-point scrubbing tower 4, a flash condenser 5, a recovery tank 6, a separation tower 7, a tail gas scrubbing tower 8, a high-boiling-point scrubbing liquid buffer tank 9, a tail gas condenser 10, a gas-liquid separator 11, a directional conversion device 12, a tower top condenser 13, a reflux tank 14, a top-harvest buffer tank 15, a tower side cooler 16, a side-harvest buffer tank 17, a tower bottom cooler 18, and a tower bottom buffer tank 19; the wet scrubbing tower 1... The liquid outlet is connected to the liquid inlet of reboiler 2, and the gas outlet of reboiler 2 is connected to the gas inlet of wet dust removal tower 1; the liquid outlet of reboiler 2 is connected to the liquid inlet of flash tank 3, the gas outlet of flash tank 3 is connected to the gas inlet of high-boiling-point scrubbing tower 4, the liquid outlet of high-boiling-point scrubbing tower 4 is connected to the liquid inlet of flash tank 3, the gas outlet of high-boiling-point scrubbing tower 4 is connected to the gas inlet of flash condenser 5, the liquid outlet of flash condenser 5 is connected to the liquid inlet of recovery tank 6, and the liquid outlet of recovery tank 6 is connected to the washing inlet of high-boiling-point scrubbing tower 4 and the liquid inlet of separation tower 7, respectively.

[0017] The outlet of the flash condenser 5 is connected to the inlet of the tail gas scrubbing tower 8, the outlet of the high-boiling-point scrubbing liquid buffer tank 9 is connected to the inlet of the tail gas scrubbing tower 8, the outlet of the tail gas scrubbing tower 8 is connected to the inlet of the tail gas condenser 10, the outlet of the tail gas condenser 10 is connected to the inlet of the high-boiling-point scrubbing liquid buffer tank 9, the outlet of the tail gas condenser 10 is connected to the inlet of the gas-liquid separator 11, and the outlet of the gas-liquid separator 11 is connected to the inlet of the directional conversion device 12.

[0018] The top outlet of the separation tower 7 is connected to the inlet of the top condenser 13, the liquid outlet of the top condenser 13 is connected to the inlet of the reflux tank 14, and the liquid outlet of the reflux tank 14 is connected to the reflux outlet of the separation tower 7 and the liquid inlet of the top extraction buffer tank 15, respectively; the side outlet of the separation tower 7 is connected to the inlet of the side cooler 16, and the liquid outlet of the side cooler 16 is connected to the inlet of the side extraction buffer tank 17; the bottom outlet of the separation tower 7 is connected to the inlet of the bottom cooler 18, the liquid outlet of the bottom cooler 18 is connected to the inlet of the bottom buffer tank 19, and the outlet of the top condenser 13 is connected to the inlet of the tail gas scrubbing tower 8.

[0019] A level sensor 20 is installed inside the reboiler 2, and a solenoid valve 21 is installed on the pipeline between the reboiler 2 and the flash tank 3. The outlet of the recovery tank 6 is connected to the inlet of the tail gas scrubbing tower 8. A pressure sensor 22 is installed inside the recovery tank 6, and a pressure relief valve 23 is installed on the pipeline between the recovery tank 6 and the tail gas scrubbing tower 8. The signal output terminals of the level sensor 20 and the pressure sensor 22 are both connected to the signal input terminal of the controller 24 via signal connection. The signal output terminal of the controller 24 is connected to the signal input terminals of the solenoid valve 21 and the pressure relief valve 23 via signal connection.

[0020] Working principle: The level sensor 20 continuously monitors the liquid level in the reboiler 2 and transmits the signal to the controller 24. When the liquid level in the reboiler 2 rises to 50%~55%, the controller opens the solenoid valve 21 to discharge the slurry in the reboiler 2 to the flash tank 3 for flash evaporation. The high-boiling gas vaporized in the flash tank 3 enters the high-boiling scrubbing tower 4 for washing. The washed slurry enters the flash tank 3, and the gas enters the flash condenser 5 for condensation. The condensed liquid enters the recovery tank 6. Part of the high-boiling liquid in the tank is sent to the high-boiling scrubbing tower 4 as washing liquid, and part is pumped into the separation tower 7 by the flash liquid pump for high-boiling distillation. The high-boiling substance with a lower boiling point is collected from the top of the separation tower 7. After being condensed by the top condenser 13, it enters the reflux tank 14. Part of the high-boiling liquid in the reflux tank 14 is used as tower reflux by the reflux pump of the separation tower 7, and part is temporarily stored in the top buffer tank 15, which will be sent to produce hydrogen-containing silicone oil later. The high-boiling liquid collected from the side of separation tower 7 is cooled by the tower side cooler 16 and then enters the side-collection buffer tank 17. The high-boiling liquid in the side-collection buffer tank 17 is then pumped to the raw material for high-boiling cracking in the single distillation and tank area via the side-collection liquid transfer pump. The high-boiling-point substances at the bottom of separation tower 7 are cooled by the tower bottom cooler 18 and then enter the tower bottom buffer tank 19. Later, they are discharged into the mobile slurry tank and sent to the slurry contact treatment unit to recover other effective components in the slurry.

[0021] The gas discharged from the flash condenser 5 and the top condenser 13 enters the tail gas scrubbing tower 8 and is scrubbed by a high-boiling scrubbing liquid. After the tail gas is scrubbed, the vented air enters the tail gas condenser 10 from the top gas phase pipe and is condensed. The liquid phase enters the high-boiling scrubbing liquid buffer tank 9 and is reused in the tail gas scrubbing tower 8. The non-condensable gas passes through the gas-liquid separator 11 and is separated into gas and liquid phases before being sent to the directional conversion unit 12.

[0022] Pressure sensor 22 constantly monitors the pressure inside the recovery tank 6 and transmits the signal to controller 24. When the pressure exceeds the set range, controller 24 controls pressure relief valve 23 to open, and the gas inside the recovery tank 6 is discharged into tail gas scrubbing tower 8, thereby ensuring that the pressure inside the recovery tank 6 is maintained within a certain range.

[0023] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A system for recovering high-boiling-point substances from organosilicon byproducts, comprising a wet scrubbing tower and a reboiler, wherein the liquid outlet of the wet scrubbing tower is connected to the liquid inlet of the reboiler, and the gas outlet of the reboiler is connected to the gas inlet of the wet scrubbing tower; characterized in that, It also includes a flash tank, a high-boiling-point scrubbing tower, a flash condenser, a recovery tank, and a separation tower; the outlet of the reboiler is connected to the inlet of the flash tank, the outlet of the flash tank is connected to the inlet of the high-boiling-point scrubbing tower, the outlet of the high-boiling-point scrubbing tower is connected to the inlet of the flash tank, the outlet of the high-boiling-point scrubbing tower is connected to the inlet of the flash condenser, the outlet of the flash condenser is connected to the inlet of the recovery tank, and the outlet of the recovery tank is connected to both the scrubbing inlet of the high-boiling-point scrubbing tower and the inlet of the separation tower.

2. The organosilicon by-product high-boiling point recovery system according to claim 1, characterized in that, It also includes a tail gas scrubbing tower, a high-boiling-point scrubbing liquid buffer tank, a tail gas condenser, a gas-liquid separator, and a directional conversion device; the outlet of the flash condenser is connected to the inlet of the tail gas scrubbing tower, the outlet of the high-boiling-point scrubbing liquid buffer tank is connected to the inlet of the tail gas scrubbing tower, the outlet of the tail gas scrubbing tower is connected to the inlet of the tail gas condenser, the outlet of the tail gas condenser is connected to the inlet of the high-boiling-point scrubbing liquid buffer tank, the outlet of the tail gas condenser is connected to the inlet of the gas-liquid separator, and the outlet of the gas-liquid separator is connected to the inlet of the directional conversion device.

3. The organosilicon by-product high-boiling point recovery system according to claim 2, characterized in that, It also includes a top condenser, a reflux tank, a top-output buffer tank, a side cooler, a side-output buffer tank, a bottom cooler, and a bottom buffer tank; the top outlet of the separation tower is connected to the inlet of the top condenser, the liquid outlet of the top condenser is connected to the inlet of the reflux tank, and the liquid outlet of the reflux tank is connected to both the reflux outlet of the separation tower and the inlet of the top-output buffer tank; the side outlet of the separation tower is connected to the inlet of the side cooler, and the liquid outlet of the side cooler is connected to the inlet of the side-output buffer tank; the bottom outlet of the separation tower is connected to the inlet of the bottom cooler, and the liquid outlet of the bottom cooler is connected to the inlet of the bottom buffer tank.

4. The organosilicon by-product high-boiling point recovery system according to claim 3, characterized in that, The outlet of the condenser at the top of the tower is connected to the inlet of the tail gas scrubbing tower.

5. A system for recovering high-boiling-point organic silicon byproducts according to any one of claims 2-4, characterized in that, A liquid level sensor is installed inside the reboiler, and a solenoid valve is installed on the pipeline between the reboiler and the flash tank. The outlet of the recovery tank is connected to the inlet of the tail gas scrubbing tower. A pressure sensor is installed inside the recovery tank, and a pressure relief valve is installed on the pipeline between the recovery tank and the tail gas scrubbing tower. The signal output terminals of the liquid level sensor and the pressure sensor are both connected to the signal input terminal of the controller via signal connections. The signal output terminal of the controller is connected to the signal input terminals of the solenoid valve and the pressure relief valve via signal connections.

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