Composite air cooler and pipeline distribution system for chlorosilane separation

Abstract

The composite air cooler and pipeline distribution system comprises a plurality of sets of composite air coolers, the input end of each set of composite air cooler is connected with the output end of a feeding distributor through a multi-stage feeding pipeline, the input end of the feeding distributor is connected with a gas phase pipeline at the top of a self-desorption low tower, and the input end of the feeding distributor is connected with a gas phase pipeline at the bottom of the self-desorption low tower. The output end of each group of composite air coolers is connected with the input end of a collecting pipeline through a multi-stage discharge pipeline, and the output end of the collecting pipeline is connected with a pipeline of a low removal tower reflux tank; the pipe diameter of the multi-stage feeding pipeline in the material flowing direction is gradually reduced, and the pipe diameter of the multi-stage discharging pipeline in the material flowing direction is gradually increased; the pipeline distribution system disclosed by the invention can solve the problem of non-uniform condensation under the condition that a plurality of groups of composite air coolers are used in the chlorosilane rectification separation process, and plays a decisive role in judging whether the plurality of groups of composite air coolers can be successfully applied to the chlorosilane separation process or not.

Description

Technical Field

[0001] The invention relates to the technical field of distillation systems for separation of organosilicon chlorosilanes, in particular to a composite air cooler and a pipeline distribution system for separation of chlorosilanes. Background Art

[0002] In the production process of organic silicon, the separation of silicic acid and chlorosilane usually uses distillation. Traditional devices often use shell and tube heat exchangers as the condenser of the distillation tower. The shell and tube heat exchanger uses circulating cooling water as the cooling medium. Because there are many gaseous materials at the top of the distillation tower and the condensation volume is huge, a large amount of circulating water will be consumed, especially when the single distillation separation capacity is high. The single capacity of our chlorosilane separation unit has reached 400,000 tons / year, and the industry's most advanced coupling energy-saving system has been applied, which has minimized heat energy loss. According to calculations, the total consumption of circulating cooling water in the normal operation of the chlorosilane separation unit is still about 3200m³ / h; the composite air cooler, as a new type of heat exchanger developed in recent years, has good heat exchange effect and has been gradually and widely used in industrial production in recent years. The composite air cooler relies on the principle of soft water spray + air cooling to directly exchange heat with the environment. The process completely eliminates the use of cooling media such as circulating water. Therefore, our company applies advanced composite air cooler equipment to the distillation separation system to replace the traditional shell and tube heat exchanger. In order to meet the performance requirements of the equipment, the de-lowering tower composite air cooler of the silicon-chlorosilane separation unit is divided into 4 groups, reaching 24 gas-phase feed and liquid-phase discharge ports. In order to successfully apply the composite air cooler to the de-lowering tower system, the gas-phase feed pipe and liquid-phase discharge pipe of the de-lowering tower need to be reasonably arranged to match the composite air cooler. Therefore, how to layout the pipeline plays a decisive role in whether multiple groups of composite air coolers can be successfully applied to the chlorosilane separation process. This is an urgent problem to be solved. Summary of the invention

[0003] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide a composite air cooler and a pipeline distribution system for chlorosilane separation, and apply multiple sets of composite air coolers to the chlorosilane separation process.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a composite air cooler and pipeline distribution system for chlorosilane separation, comprising a plurality of composite air coolers, the input end of each composite air cooler is connected to the output end of a feed distributor through a multi-stage feed pipeline, the input end of the feed distributor is connected to the gas phase pipeline at the top of a de-low tower, the output end of each composite air cooler is connected to the input end of a collecting pipeline through a multi-stage discharge pipeline, and the output end of the collecting pipeline is connected to the de-low tower reflux tank pipeline; the diameter of the multi-stage feed pipeline along the material flow direction gradually decreases, and the diameter of the multi-stage discharge pipeline along the material flow direction gradually increases.

[0005] Preferably, the number of the composite air coolers is four, which are distributed in a rectangular array in a plane area and are symmetrically arranged in pairs.

[0006] Preferably, the feed distributor comprises a feed main pipe connected to the gas phase pipeline at the top of the degassing tower, the outlet end of the feed main pipe is vertically connected to the center of the feed branch pipe, the end of the feed branch pipe is vertically connected to the center of the feed connecting pipe, and the end of the feed connecting pipe is connected to the inlet end of the multi-stage feed pipeline through a reducer.

[0007] Preferably, the multi-stage feed pipeline includes a first-stage feed pipe connected to a feed connecting pipe via a reducer, the first-stage feed pipe outlet is connected to a second-stage feed pipe inlet via a reducer, the second-stage feed pipe outlet is connected to a third-stage feed pipe, the third-stage feed pipe outlet is connected to a fourth-stage feed pipe inlet, and the fourth-stage feed pipe outlet is connected to an input end of a composite air cooler. Preferably, the composite air cooler has six input ends and six four-stage feed pipes; the first-stage feed pipe outlet is vertically connected to the second-stage feed pipe inlet through a first right-angle bend, the first-stage feed pipe, the second-stage feed pipe, the third-stage feed pipe and the fourth-stage feed pipe are all parallel to the horizontal reference plane, and the third-stage feed pipe outlet is vertically connected to the fourth-stage feed pipe inlet through a second right-angle bend.

[0008] Preferably, the nominal diameters of the feed main pipe, feed branch pipe and feed connecting pipe are 700 mm, the nominal diameter of the first-level feed pipe is 450 mm, the nominal diameter of the second-level feed pipe is 300 mm, the nominal diameter of the third-level feed pipe is 250 mm, and the nominal diameter of the fourth-level feed pipe is 150 mm.

[0009] Preferably, the collecting pipeline includes a collecting main pipe connected to the removal low tower reflux tank pipeline, and the collecting main pipe is connected to the output end of the multi-stage discharge pipeline through a collecting branch pipe.

[0010] Preferably, the multi-stage discharge pipeline includes a first-stage discharge pipe connected to the input end of the collecting branch pipe, the inlet of the first-stage discharge pipe is connected to the outlet of the second-stage discharge pipe through a reducer, the inlet of the second-stage discharge pipe is connected to the outlet of the third-stage discharge pipe through a reducer, and the inlet of the third-stage discharge pipe is connected to the output end of the composite air cooler.

[0011] Preferably, the composite air cooler has six output ends and six three-stage discharge pipes.

[0012] Preferably, the nominal diameter of the collecting main pipe is 300 mm, the nominal diameter of the collecting branch pipe is 250 mm, the nominal diameter of the first-level discharge pipe is 250 mm, the nominal diameter of the second-level discharge pipe is 200 mm, and the nominal diameter of the tertiary discharge pipe is 100 mm.

[0013] Beneficial effects of the present invention: The pipeline distribution system of the present invention can solve the problem of uneven condensation when using multiple sets of composite air coolers in the chlorosilane distillation separation process, and plays a decisive role in whether the multiple sets of composite air coolers can be successfully applied to the chlorosilane separation process; through this symmetrical horizontal distribution structure, each level of pipeline can be on the same horizontal plane, ensuring that the pressure at each location of the pipeline is the same, and can also ensure that the final total pressure drop range is within the normal range, so that the temperature difference of the liquid phase branch pipes of the composite air coolers in different areas is extremely small. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the layout of a composite air cooler and a pipeline distribution system for chlorosilane separation; Figure 2 for Figure 1 An enlarged structural diagram of the area where the multi-stage feed pipeline is located; Figure 3 for Figure 1 An enlarged structural diagram of the area where the multi-stage discharge pipeline is located; Figure 4 A schematic diagram of a top view of the structure of the connection between the feed distributor and the first-stage feed pipe of the multi-stage feed pipeline; Figure 5 for Figure 4 AA cross-sectional structural diagram; Figure 6 It is a top view structural schematic diagram of a multi-stage feed pipeline; Figure 7 for Figure 6 A schematic diagram of the front view of the structure in which the outlet of the tertiary feed pipe is connected to the second right-angle elbow. DETAILED DESCRIPTION

[0015] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0016] like Figure 1-7As shown, a composite air cooler and pipeline distribution system for chlorosilane separation includes multiple groups of composite air coolers 1, the input end of each group of composite air coolers 1 is connected to the output end of a feed distributor 3 through a multi-stage feed pipeline 2, the input end of the feed distributor 3 is connected to a gas phase pipeline 4 from the top of a de-low tower, the output end of each group of composite air coolers 1 is connected to the input end of a collecting pipeline 6 through a multi-stage discharge pipeline 5, and the output end of the collecting pipeline 6 is connected to a de-low tower reflux tank pipeline 7; the diameter of the multi-stage feed pipeline 2 along the material flow direction gradually decreases, and the diameter of the multi-stage discharge pipeline 5 along the material flow direction gradually increases. The gas phase condensation capacity of the de-lowering tower in the chlorosilane separation process is 67984.216 kg / h-149565.275 kg / h, the gas phase pressure is 0.03 MPa G-0.08 MPa G, the gas phase temperature is 50℃-70℃, and the liquid phase temperature after condensation is 30℃-40℃.

[0017] Preferably, the number of the composite air coolers 1 is four, which are distributed in a rectangular array in the plane area and are symmetrically arranged in pairs. Figure 1 As shown, a group of composite air coolers 1 are provided in each of the four regions EA, EB, EC, and ED. The four groups of composite air coolers have the same equipment performance and the same external dimensions, and the pipe openings on each group of composite air coolers are arranged exactly the same; the arrangement spacing H1 between EA and ED is 3000mm, EA and ED are arranged symmetrically, and the symmetry axis is Z1; the arrangement spacing H2 between EB and EC is 3000mm, EB and EC are arranged symmetrically, and the symmetry axis is Z1; the arrangement spacing H3 between EA and EB is 7000mm, EA and EB are arranged symmetrically, and the symmetry axis is Z2; the arrangement spacing H4 between ED and EC is 7000mm, ED and EC are arranged symmetrically, and the symmetry axis is Z2.

[0018] There are gas-phase feed pipe opening (N1) and liquid-phase discharge pipe opening (N2) on the composite air cooler 1; taking the bottom edge of the de-lowering tower composite air cooler as the horizontal reference surface layer of 0m, the center of the gas-phase feed pipe opening (N1) is 44870mm away from the horizontal reference surface layer of 0m, and the center spacing between the 6 gas-phase feed pipe openings (N1) adjacent to each group of composite air coolers 1 is 1465mm; the center of the liquid-phase discharge pipe opening (N2) is 2132mm away from the horizontal reference surface layer of 0m, and the center spacing between the 6 liquid-phase discharge pipe openings (N2) adjacent to each group of composite air coolers 1 is 980mm.

[0019] Preferably, the feed distributor 3 includes a feed main pipe 3.1 connected to the gas phase pipeline 4 at the top of the self-degassing tower, the outlet end of the feed main pipe 3.1 is vertically connected to the center of the feed branch pipe 3.2, the end of the feed branch pipe 3.2 is vertically connected to the center of the feed pipe 3.3, and the end of the feed pipe 3.3 is connected to the inlet end of the multi-stage feed pipeline 2 through a reducer. In this embodiment, the feed main pipe 3.1 and the feed branch pipe 3.2 are both straight pipe sections, vertically connected to each other, and the connection direction of the feed main pipe 3.1 and the feed branch pipe 3.2 is parallel to the horizontal reference plane; the feed branch pipe 3.2 is parallel to the horizontal reference plane, and the elevation of its pipeline center relative to the horizontal reference plane is 73560mm; the end of the feed branch pipe 3.2 is also vertically connected to the feed pipe 3.3, and the connection direction is parallel to the horizontal reference plane; the feed pipe 3.3 is parallel to the horizontal reference plane, and the elevation of its pipeline center relative to the horizontal reference plane is 73560mm; the reducers on both sides are installed with the bottom flat; Preferably, the multi-stage feed pipeline 2 includes a first-stage feed pipe 2.1 connected to a feed connecting pipe 3.3 via a reducer, the outlet of the first-stage feed pipe 2.1 is connected to the inlet of a second-stage feed pipe 2.2 via a reducer, the outlet of the second-stage feed pipe 2.2 is connected to a third-stage feed pipe 2.3, the outlet of the third-stage feed pipe 2.3 is connected to the inlet of a fourth-stage feed pipe 2.4, and the outlet of the fourth-stage feed pipe 2.4 is connected to the input end of the composite air cooler 1. Preferably, the composite air cooler 1 has six input ends, and the number of the four-stage feed pipes 2.4 is six; the outlet of the first-stage feed pipe 2.1 is vertically connected to the inlet of the second-stage feed pipe 2.2 through the first right-angle elbow 2.5, the first-stage feed pipe 2.1, the second-stage feed pipe 2.2, the third-stage feed pipe 2.3 and the fourth-stage feed pipe 2.4 are all parallel to the horizontal reference plane, and the outlet of the third-stage feed pipe 2.3 is vertically connected to the inlet of the fourth-stage feed pipe 2.4 through the second right-angle elbow 2.6. In this embodiment, when the chlorosilane separation system is operated at a load of 50% to 110%, the total pressure drop of the four-stage distribution pipe is not higher than 10Kpa and not lower than 3 Kpa. In this embodiment, the center elevation of the first-stage feed pipe 2.1 relative to the horizontal reference plane is 72290mm; the center elevation of the second-stage feed pipe 2.2 and the third-stage feed pipe 2.3 relative to the horizontal reference plane is 56920mm, and the center elevation of the fourth-stage feed pipe 2.4 relative to the horizontal reference plane is 44870mm. Through the above pipeline layout structure, each stage of the pipeline can be in the same horizontal plane to ensure the same pressure at each location of the pipeline, and the final total pressure drop range can also be ensured to be within the normal range.

[0020] Preferably, the nominal diameters of the feed main pipe 3.1, the feed branch pipe 3.2 and the feed connecting pipe 3.3 are 700 mm, the nominal diameter of the first-level feed pipe 2.1 is 450 mm, the nominal diameter of the second-level feed pipe 2.2 is 300 mm, the nominal diameter of the tertiary feed pipe 2.3 is 250 mm, and the nominal diameter of the fourth-level feed pipe 2.4 is 150 mm.

[0021] Preferably, the collecting pipeline 6 comprises a collecting main pipe 6.1 connected to the removal low tower reflux tank pipeline 7, and the collecting main pipe 6.1 is connected to the output end of the multi-stage discharge pipeline 5 through a collecting branch pipe 6.2.

[0022] Preferably, the multi-stage discharge pipeline 5 includes a first-stage discharge pipe 5.1 connected to the input end of the collecting branch pipe 6.2, the inlet of the first-stage discharge pipe 5.1 is connected to the outlet of the second-stage discharge pipe 5.2 through a reducer, the inlet of the second-stage discharge pipe 5.2 is connected to the outlet of the tertiary discharge pipe 5.3 through a reducer, and the inlet of the tertiary discharge pipe 5.3 is connected to the output end of the composite air cooler 1.

[0023] Preferably, the composite air cooler 1 has six output ends and the number of the third-stage discharge pipes 5.3 is six.

[0024] Preferably, the nominal diameter of the collecting main pipe 6.1 is 300 mm, the nominal diameter of the collecting branch pipe 6.2 is 250 mm, the nominal diameter of the first-level discharge pipe 5.1 is 250 mm, the nominal diameter of the second-level discharge pipe 5.2 is 200 mm, and the nominal diameter of the tertiary discharge pipe 5.3 is 100 mm.

[0025] In the above technical solution, the pipeline classification sizes of each level are calculated by the Bernoulli equation, the continuity equation and the Fanning equation, and the calculated gas phase flow rate is not higher than 15m / s.

[0026] Example 1 When the degassing tower of the chlorosilane separation system is operated at 50% load, the gas volume at the top of the tower is 67984.216 kg / h, the temperature is 55°C, and the pressure is 0.04 MPa G. Within the capacity adjustment load of the degassing tower composite air cooler, the pressure drop of the gas distribution pipe is 4Kpa~5 Kpa, the total liquid temperature after condensation is 32°C, and the temperature difference of the liquid distribution pipes of EA, EB, EC, and ED is less than 0.6°C. The amount of circulating water cooling water that can be saved is 575m³ / h.

[0027] Example 2 When the degassing tower of the chlorosilane separation system is operated at 70% load, the gas volume at the top of the tower is 95177.902 kg / h, the temperature is 58°C, and the pressure is 0.05 MPa G. Within the capacity adjustment load of the degassing tower composite air cooler, the pressure drop of the gas distribution pipe is 5Kpa~7 Kpa, the liquid temperature after condensation is 35°C, and the temperature difference of the liquid distribution pipes of EA, EB, EC, and ED is less than 1°C. The amount of circulating water cooling water that can be saved is 805 m³ / h.

[0028] Example 3 When the degassing tower of the chlorosilane separation system operates at 100% load, the gas volume at the top of the tower is 135968.432 kg / h, the temperature is 63°C, and the pressure is 0.07 MPa G. Within the capacity adjustment load of the degassing tower composite air cooler, the pressure drop of the gas distribution pipe is 7 Kpa~8 Kpa, the liquid temperature after condensation is 37°C, and the temperature difference of the liquid distribution pipes of EA, EB, EC, and ED is less than 1.5°C. The amount of circulating water cooling water that can be saved is 1150 m³ / h.

[0029] Example 4 When the degassing tower of the chlorosilane separation system is operated at 110% load, the gas volume at the top of the tower is 149565.275 kg / h, the temperature is 68℃, and the pressure is 0.08MPa G. Within the capacity adjustment load of the degassing tower composite air cooler, the pressure drop of the gas distribution pipe is 8 Kpa~9 Kpa, the liquid temperature after condensation is 39℃, and the temperature difference of the liquid distribution pipes of EA, EB, EC, and ED is less than 2℃. The amount of circulating water cooling water that can be saved is 1265 m³ / h.

[0030] The above embodiments are only preferred technical solutions of the present invention and should not be regarded as limiting the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A composite air cooler and pipeline distribution system for chlorosilane separation, comprising a plurality of composite air coolers (1), characterized in that: The input end of each group of composite air coolers (1) is connected to the output end of a feed distributor (3) via a multi-stage feed pipeline (2); the input end of the feed distributor (3) is connected to a gas phase pipeline (4) at the top of a degassing tower; the output end of each group of composite air coolers (1) is connected to the input end of a collecting pipeline (6) via a multi-stage discharge pipeline (5); the output end of the collecting pipeline (6) is connected to a degassing tower reflux tank pipeline (7); the diameter of the multi-stage feed pipeline (2) gradually decreases along the material flow direction, and the diameter of the multi-stage discharge pipeline (5) gradually increases along the material flow direction.

2. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 1, characterized in that: The number of the composite air coolers (1) is four, which are distributed in a rectangular array in a plane area and are symmetrically arranged in pairs.

3. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 2, characterized in that: The feed distributor (3) comprises a feed main pipe (3.1) connected to the gas phase pipeline (4) at the top of the degassing tower, the outlet end of the feed main pipe (3.1) being vertically connected to the center of a feed branch pipe (3.2), the end of the feed branch pipe (3.2) being vertically connected to the center of a feed pipe (3.3), and the end of the feed pipe (3.3) being connected to the inlet end of the multi-stage feed pipeline (2) via a reducer.

4. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 3, characterized in that: The multi-stage feed pipeline (2) comprises a first-stage feed pipe (2.1) connected to a feed pipe connection (3.3) via a reducer, the first-stage feed pipe (2.1) outlet is connected to the second-stage feed pipe (2.2) inlet via a reducer, the second-stage feed pipe (2.2) outlet is connected to the third-stage feed pipe (2.3), the third-stage feed pipe (2.3) outlet is connected to the fourth-stage feed pipe (2.4) inlet, and the fourth-stage feed pipe (2.4) outlet is connected to the input end of the composite air cooler (1).

5. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 4, characterized in that: The composite air cooler (1) has six input ends, and the number of the four-stage feed pipes (2.4) is six; the outlet of the first-stage feed pipe (2.1) is vertically connected to the inlet of the second-stage feed pipe (2.2) through a first right-angle bend pipe (2.5); the first-stage feed pipe (2.1), the second-stage feed pipe (2.2), the third-stage feed pipe (2.3) and the fourth-stage feed pipe (2.4) are all parallel to a horizontal reference plane; the outlet of the third-stage feed pipe (2.3) is vertically connected to the inlet of the fourth-stage feed pipe (2.4) through a second right-angle bend pipe (2.6).

6. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 5, characterized in that: The nominal diameters of the main feed pipe (3.1), the feed branch pipe (3.2) and the feed connecting pipe (3.3) are 700 mm, the nominal diameter of the primary feed pipe (2.1) is 450 mm, the nominal diameter of the secondary feed pipe (2.2) is 300 mm, the nominal diameter of the tertiary feed pipe (2.3) is 250 mm, and the nominal diameter of the quaternary feed pipe (2.4) is 150 mm.

7. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 2, characterized in that: The collecting pipeline (6) comprises a collecting main pipe (6.1) connected to the stripping low tower reflux tank pipeline (7); the collecting main pipe (6.1) is connected to the output end of the multi-stage discharge pipeline (5) via a collecting branch pipe (6.2).

8. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 7, characterized in that: The multi-stage discharge pipeline (5) comprises a first-stage discharge pipe (5.1) connected to the input end of the collecting branch pipe (6.2); the inlet of the first-stage discharge pipe (5.1) is connected to the outlet of the second-stage discharge pipe (5.2) via a reducer; the inlet of the second-stage discharge pipe (5.2) is connected to the outlet of the third-stage discharge pipe (5.3) via a reducer; and the inlet of the third-stage discharge pipe (5.3) is connected to the output end of the composite air cooler (1).

9. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 8, characterized in that: The composite air cooler (1) has six output ends, and the number of the third-stage discharge pipes (5.3) is six.

10. A composite air cooler and pipeline distribution system for chlorosilane separation according to claim 9, characterized in that: The nominal diameter of the collecting main pipe (6.1) is 300 mm, the nominal diameter of the collecting branch pipe (6.2) is 250 mm, the nominal diameter of the first-level discharge pipe (5.1) is 250 mm, the nominal diameter of the second-level discharge pipe (5.2) is 200 mm, and the nominal diameter of the third-level discharge pipe (5.3) is 100 mm.

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