Search

CN-121971875-A - Spraying system for removing sediment in pre-condenser in naphthalene phthalic anhydride production

CN121971875ACN 121971875 ACN121971875 ACN 121971875ACN-121971875-A

Abstract

The application relates to a spray system for removing sediment in a pre-condenser in naphthalene-process phthalic anhydride production, which relates to the technical field of naphthalene-process phthalic anhydride production and comprises a pre-condenser body, a gas-liquid separation device, a crude phthalic anhydride intermediate tank and a switching condenser, wherein a first conveying pipe is arranged on the surface of the pre-condenser body, a filtering component is arranged on the surface of the first conveying pipe, a connecting pipe is arranged at the other end of the first conveying pipe, the other end of the connecting pipe is arranged on the surface of the gas-liquid separation device, a liquid phase pipe and a gas phase pipe are arranged on the surface of the gas-liquid separation device, and a complete gas-liquid separation and circulating spray system is constructed by integrating the pre-condenser body, the gas-liquid separation device, the crude phthalic anhydride intermediate tank and the switching condenser.

Inventors

  • GUO JINGHAN
  • CHENG KE
  • MAO LIN
  • CHEN YUHANG
  • WANG XU

Assignees

  • 南京中设石化工程有限公司

Dates

Publication Date
20260505
Application Date
20260127

Claims (8)

  1. 1. The spray system for removing sediment in a pre-condenser in naphthalene method phthalic anhydride production comprises a pre-condenser body (1), a gas-liquid separation device (2) and a crude phthalic anhydride intermediate tank (3), and a switch condenser (14), and is characterized in that the surface of the pre-condenser body (1) is provided with a first conveying pipe (4), the surface of the first conveying pipe (4) is provided with a filtering component (11), the other end of the first conveying pipe (4) is provided with a connecting pipe (5), the other end of the connecting pipe (5) is arranged on the surface of the gas-liquid separation device (2), the surface of the gas-liquid separation device (2) is provided with a liquid phase pipe (7) and a gas phase pipe (6), the other end of the liquid phase pipe (7) is provided with a third conveying pipe (10), the other end of the gas phase pipe (6) is provided with a second conveying pipe (9), the other end of the third conveying pipe (10) and the second conveying pipe (9) are arranged on the surface of the crude phthalic anhydride intermediate tank (3), the top of the crude phthalic anhydride intermediate tank (3) is provided with a connecting pipe (5), the surface of the seamless steel pipe (7) is provided with a seamless steel pipe (13), and the top of the seamless steel pipe (7) is provided with the seamless steel pipe (1), the seamless steel pipe (14) The gas phase pipes (6) are internally provided with delivery pumps.
  2. 2. The spraying system for removing sediment in the pre-condenser in the production of naphthalene meaning phthalic anhydride according to claim 1, wherein a flange (8) is arranged between the first conveying pipe (4) and the connecting pipe (5), a flange (8) is arranged between the liquid-phase pipe (7) and the third conveying pipe, and a flange (8) is arranged between the gas-phase pipe (6) and the second conveying pipe (9).
  3. 3. The spraying system for removing sediment in the pre-condenser in naphthalene-making phthalic anhydride production according to claim 1, wherein the filtering component (11) comprises a frame (1105), the frame (1105) is arranged on the surface of the first conveying pipe (4), a clamping groove (1101) is formed in the top of the frame (1105), a connecting plate (1103) is clamped in the clamping groove (1101), a sealing sleeve (1102) is arranged between the connecting plate (1103) and the clamping groove (1101), a filter screen (1104) is arranged at the bottom of the connecting plate (1103), and the filter screen (1104) is positioned in the frame (1105).
  4. 4. The spraying system for removing sediment in the pre-condenser in the production of naphthalene meaning phthalic anhydride according to claim 1, wherein the inner wall of the gas-liquid separation device (2) is provided with a pipe body (201), the surface of the pipe body (201) is provided with a spiral blade (202), and the position, close to the lower part, of the inner wall of the gas-liquid separation device (2) is provided with a liquid separating plate (203).
  5. 5. The spray system for removing sediment in the pre-condenser in naphthalene acetic anhydride production according to claim 1, wherein the top of the pre-condenser body (1) is provided with a spray assembly (12), the spray assembly (12) comprises a top plate (1201), the top plate (1201) is arranged at the top of the pre-condenser body (1), the bottom of the top plate (1201) is provided with a connecting block (1207), the surface of the connecting block (1207) is provided with a first connecting frame (1208) and a second connecting frame (1209), the first connecting frame (1208) is movably connected with the second connecting frame (1209) through a pin shaft, the inner wall of the first connecting frame (1208) is provided with a connecting rod (1210), the surface of the connecting rod (1210) is rotatably connected with a connecting cylinder (1206), the bottom of the connecting block (1207) is rotatably connected with a rotating shaft (1204), the bottom of the rotating shaft (1204) is provided with a crank (1205), the crank (1205) is in an L shape, the surface of the connecting cylinder (1212) is provided with a first connecting frame (1208) and the bottom of the connecting cylinder (1212) is provided with a round connecting frame 1213, the round connecting cylinder (1211) is provided with a round connecting frame (1211) and the round connecting frame (1211) is provided with a round connecting tube 1211), the top of the top plate (1201) is provided with a driving motor (1203), and the other end of the output shaft of the driving motor (1203) is fixedly connected with the shaft end of the rotating shaft (1204).
  6. 6. The spray system for removing sediment in a pre-condenser in naphthalene acetic anhydride production according to claim 5, wherein a plurality of groups of universal connecting balls (1213) are arranged at the bottom of the circular frame (1211), an atomizing nozzle (1202) is arranged on the surface of the universal connecting balls (1213), and the universal connecting balls (1213) are communicated with the atomizing nozzle (1202).
  7. 7. The spray system for removing sediment in the pre-condenser in naphthalene acetic anhydride production according to any one of claims 1-5, wherein the surface of the seamless steel tube (13) is provided with a pump body (15), and the other end of the seamless steel tube (13) is fixedly arranged in the installation tube (1212) in a penetrating manner.
  8. 8. The spray system for removing sediment in the pre-condenser in naphthalene-process phthalic anhydride production according to any one of claims 1-7, wherein the gas-liquid mixture in the pre-condenser body (1) is firstly temporarily stored in a crude phthalic anhydride intermediate tank (3) through a liquid phase pipe (7), the uncondensed gas phase is temporarily stored in the crude phthalic anhydride intermediate tank (3) through a third conveying pipe (10), solid impurities and large-particle sediment entrained in the mixed gas are intercepted by a filter screen (1104) of the filter assembly (11), the filtered gas-liquid mixture enters a gas-liquid separation device (2), a pipe body (201) with a spiral blade (202) in the device accelerates gas-liquid separation through the cyclone effect, the liquid phthalic anhydride is further separated from uncondensed gas phase through a liquid phase plate (203) at the lower part, the separated liquid phase is then delivered to the crude phthalic anhydride intermediate tank (3) through the liquid phase pipe (7), the uncondensed gas phase is then delivered to the crude phthalic anhydride intermediate tank (14) through the pipe (201), the gas phase pipe (6) and a second conveying pipe (9) enters a switching condenser (14) to conduct secondary condensation, the separated liquid phase anhydride is delivered to the crude phthalic anhydride through the pre-condenser body (13) through the intermediate tank (3), the separated liquid phase anhydride is pre-condensed in the pump body (13), the spray assembly (12) atomizes the liquid phthalic anhydride into a uniform liquid film through an atomizing nozzle (1202) with a universal connection ball head (1213) at the bottom of the annular frame, the spray liquid can dissolve solid sediments on the inner wall and parts of the pre-condenser, the mixed liquid formed after spraying flows back to the bottom of the pre-condenser, the mixed liquid is separated through the filter assembly (11) and the gas-liquid separation device (2) again, the liquid reenters the crude phthalic anhydride intermediate tank (3) to form spray liquid, condensate and closed loop circulation, and finally, the liquid phthalic anhydride stored in the crude phthalic anhydride intermediate tank (3) is conveyed to a subsequent phthalic anhydride refining unit for purification.

Description

Spraying system for removing sediment in pre-condenser in naphthalene phthalic anhydride production Technical Field The invention relates to the field of naphthalene-making phthalic anhydride production, in particular to a spraying system for removing sediment in a pre-condenser in naphthalene-making phthalic anhydride production. Background The key principle of the naphthalene process phthalic anhydride production process is that the industrial naphthalene is gasified to mix the gasified naphthalene with air in certain proportion, and the mixture is catalyzed by special catalyst to produce phthalic anhydride product, and the production process is a multi-unit cooperative system engineering, which generally comprises a raw material pretreatment unit, an oxidation reaction unit, a phthalic anhydride refining unit, a boiler water supply unit, a tail gas treatment unit and the like, the oxidation unit is used as a core link for generating the crude phthalic anhydride and can be further divided into two key processes of oxidation reaction and crude phthalic anhydride condensation, wherein the two key processes are that naphthalene oxidation reaction is completed in a reactor to generate high-temperature mixed gas containing phthalic anhydride, unreacted gas and byproducts, and the other key processes are that the high-temperature mixed gas is subjected to condensation treatment to realize separation and collection of the crude phthalic anhydride. In the condensation process of the crude phthalic anhydride, the prior art generally adopts a combined condensation system of a gas cooler, a pre-condenser and a switching condenser, high-temperature reaction mixed gas firstly enters the gas cooler for preliminary cooling, then enters the pre-condenser for further condensation, partial gaseous phase phthalic anhydride is converted into liquid phase, uncondensed gaseous phase enters the switching condenser for completing secondary condensation, and finally, the liquefaction recovery of most of phthalic anhydride is realized. However, the existing combined condensation process still has obvious defects in actual operation, and when the high-temperature reaction mixed gas is initially condensed in the pre-condenser, because the mixed gas contains a small amount of high-boiling-point byproducts, the byproducts can be gradually separated out along with the condensation process of phthalic anhydride and are deposited on the inner wall of the pre-condenser, the surface of a heat exchange tube and a gas-liquid separation part in a solid form. Along with the extension of operating time, solid sediment can be thickened gradually, and not only can the heat transfer area be reduced, heat transfer efficiency is reduced, and the condensation effect is reduced, and the gas-liquid separation effect is influenced, so that the maintenance frequency and the operating cost of equipment are increased. Aiming at the problems, the invention innovatively designs a spray system for removing sediment in the pre-condenser in naphthalene-process phthalic anhydride production, the system realizes the high-efficiency separation of liquid phthalic anhydride and gas phase by means of a gas-liquid separation device at the bottom of the pre-condenser, the separated liquid phthalic anhydride and a liquid phase product of a switching condenser are together introduced into a crude phthalic anhydride intermediate tank, part of liquid in the crude phthalic anhydride intermediate tank is conveyed to a spray pipe at the top of the pre-condenser through a pump body, a uniform liquid film is formed through an atomizing nozzle and is sprayed regularly, and solid sediment in the pre-condenser is removed by utilizing the dissolution effect of the spray liquid. Disclosure of Invention The application aims to provide a spraying system for removing sediment in a pre-condenser in naphthalene acetic anhydride production so as to solve the problem that the condensing effect of the pre-condenser is reduced after long-term use. The spray system for removing sediment in the pre-condenser in naphthalene acetic anhydride production adopts the following technical scheme that the spray system comprises a pre-condenser body, a gas-liquid separation device and a crude acetic anhydride intermediate tank, a switching condenser is arranged on the surface of the pre-condenser body, a first conveying pipe is arranged on the surface of the first conveying pipe, a filtering component is arranged on the surface of the first conveying pipe, a connecting pipe is arranged at the other end of the first conveying pipe, the other end of the connecting pipe is arranged on the surface of the gas-liquid separation device, a liquid phase pipe and a gas phase pipe are arranged on the surface of the gas-liquid separation device, a third conveying pipe is arranged at the other end of the liquid phase pipe, a second conveying pipe is arranged at the other end of the gas phase pipe, the other ends of