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EP0701473A1 - Procede de reaction exothermique et endothermique - Google Patents

Procede de reaction exothermique et endothermique

Info

Publication number
EP0701473A1
EP0701473A1 EP95915535A EP95915535A EP0701473A1 EP 0701473 A1 EP0701473 A1 EP 0701473A1 EP 95915535 A EP95915535 A EP 95915535A EP 95915535 A EP95915535 A EP 95915535A EP 0701473 A1 EP0701473 A1 EP 0701473A1
Authority
EP
European Patent Office
Prior art keywords
tube
tubes
reaction
fluid
mixture
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP95915535A
Other languages
German (de)
English (en)
Inventor
Hang-Chang Bobby Chen
Gerald F. Achee
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Occidental Chemical Corp
Original Assignee
Occidental Chemical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Occidental Chemical Corp filed Critical Occidental Chemical Corp
Publication of EP0701473A1 publication Critical patent/EP0701473A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C11/00—Aliphatic unsaturated hydrocarbons
    • C07C11/02—Alkenes
    • C07C11/04—Ethylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J12/00—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor
    • B01J12/005—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor carried out at high temperatures, e.g. by pyrolysis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/24—Stationary reactors without moving elements inside
    • B01J19/2405—Stationary reactors without moving elements inside provoking a turbulent flow of the reactants, such as in cyclones, or having a high Reynolds-number
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/24—Stationary reactors without moving elements inside
    • B01J19/2415—Tubular reactors
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C1/00—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon
    • C07C1/26—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only halogen atoms as hetero-atoms
    • C07C1/30—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only halogen atoms as hetero-atoms by splitting-off the elements of hydrogen halide from a single molecule
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00049—Controlling or regulating processes
    • B01J2219/00051—Controlling the temperature
    • B01J2219/00074—Controlling the temperature by indirect heating or cooling employing heat exchange fluids
    • B01J2219/00117—Controlling the temperature by indirect heating or cooling employing heat exchange fluids with two or more reactions in heat exchange with each other, such as an endothermic reaction in heat exchange with an exothermic reaction
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00049—Controlling or regulating processes
    • B01J2219/00051—Controlling the temperature
    • B01J2219/0015—Controlling the temperature by thermal insulation means
    • B01J2219/00155—Controlling the temperature by thermal insulation means using insulating materials or refractories
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00049—Controlling or regulating processes
    • B01J2219/00051—Controlling the temperature
    • B01J2219/00159—Controlling the temperature controlling multiple zones along the direction of flow, e.g. pre-heating and after-cooling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00049—Controlling or regulating processes
    • B01J2219/00164—Controlling or regulating processes controlling the flow

Definitions

  • This invention relates to a method of exothermically and endothermically reacting a fluid, where heat from the exothermic reaction is transferred to the endothermic reaction.
  • the invention relates to a method of making ethylene by exothermically reacting ethane and chlorine gases to form ethyl chloride and hydrogen chloride and using the heat from that reaction to endothermically dissociate the ethyl chloride into ethylene and hydrogen chloride.
  • the reactant mixture passes through the inside of the tube then up over the outside of the tube, and the reaction heat is conducted through the tube surface.
  • the tube can be cooled around the area where the reactants enter the tube to prevent any reaction from occurring prematurely and, because of the design of this reactor, scaling up the reactor to handle larger quantities of reactants can be easily accomplished by adding more tubes to the reactor.
  • Figure 1 is a side view in section showing a certain presently preferred embodiment of a reactor according to this invention.
  • Figure 2 is an enlargement of a portion of Figure 1 showing the end of the tubes.
  • Figure 3 is an enlargement of a portion of Figure 1 showing how the outer tube is held in position.
  • reactor 1 consists of flue gas section 2, tube bundles 3, product outlet chamber 4, cooling chamber 5, process inlet/reaction tubes 6, and process gas inlet head 7.
  • Flue gas section 2 of reactor 1 is comprised of a large diameter pipe or rolled plate 8 which is split in half and is flanged along the horizontal seams to form upper case section 9 and lower case section 10.
  • Flue gas inlet nozzle 11 is installed in lower case section 10 and flue gas outlet nozzle 12 is installed in upper case section 9.
  • Flanges 13 are installed on the flue gas inlet end of upper and lower case sections 9 and 10, and metal end cover 14 is provided to seal this end of the unit.
  • castable refractory 15 is applied along the inner walls of upper and lower case sections 9 and 10 and to inner wall of end cover 14. Referring especially to Figures 2 and 3, tube bundles 3 are welded to tube sheet 16. Tube bundles 3 are formed from metal outer tubes 17, which have fins 18 to enhance heat transfer.
  • Silicon carbide inner tubes 19 are open-ended on one end and are closed on the other end and have a groove 20 around the circumference of the tube at the open end. These tubes are held in place by packing assembly 21.
  • packing assembly 21 consists of an inner split ring 22, which fits into groove 20 on silicon carbide inner tube 19. Keeper ring 23 holds split ring 22 in position and aligns silicon carbide inner tube 19 within metal outer tube 17. Grafoil gaskets 24 and 25, when compressed, seal the packing assembly to top plate 26, which is the upper half of packing assembly 21. Packing assembly 21 is bolted together to form the seal between tube sheet 16, metal outer tube 17, and tube bundle 3. Referring to Figure 2, graphite powder 27 is packed into the void between the inner wall of metal outer tube 17 and the outer wall of silicon carbide inner tube 19, and acts as the heat transfer media. Grafoil packing rings 28 are installed around the circumference of silicon carbide inner tubes 19 to provide a seal between silicon carbide inner tubes 19 and metal outer tubes 17.
  • Metal plugs 29 are welded into the ends of metal outer tubes 17 to seal the tubes and hold grafoil packing rings 28 in position.
  • metal baffle plates 30 are placed in strategic positions along the length of tube bundles 3.
  • Metal baffle plates 30 direct the flow of the flue gas across tube bundles 3 in flue gas section 2 of the reactor vessel 1.
  • Grafoil gasket material 31 is placed around the circumference of tube sheet 16.
  • tube bundles 3 are placed into the lower case section 10 of flue gas section 2.
  • the upper case section 9 of flue gas section 2 is bolted into position to form the entire flue gas section 2 and tube bundles 3 of reactor vessel 1.
  • Product outlet chamber 4 is constructed from a large diameter pipe 32. Pipe 32 has flange 33 on one end which is bolted to tube sheet 16.
  • Flange 34 of drilled front tube sheet 35 on the opposite end of pipe 32 is bolted to flange 36 of process inlet head 7.
  • An intermediate tube sheet 37 is welded in position within the internal diameter of the body of pipe 32.
  • Small diameter pipes 38 are installed between the front tube sheet 35 and intermediate tube sheet 37 and are seal welded to both tube sheets forming cooling chamber 5.
  • Pipe couplings are welded to the lower and upper portions of cooling chamber 5 to provide water inlet port 39 and water outlet port 40.
  • Castable refractory 41 is installed on both ends of product outlet chamber 4 for heat conservation.
  • Product outer chamber 4 is bolted to tube sheet 16.
  • Pipe nozzle 42 provides for product outlet.
  • Process inlet/reaction tubes 6 are small diameter silicon carbide tubes which are inserted into front tube sheet 35 openings, pass through sealed pipes 38 of the cooling chamber, through product outlet chamber 4 and into the open ends of silicon carbide inner tubes 19 of tube bundles 3.
  • the process inlet/reaction tubes 6 terminate near the bottom of the tube bundle inner tubes 19.
  • Grafoil packing 43 is installed around the circumferences of process inlet/reaction tubes 6 for the length of cooling chamber 5 to seal the area between product outlet chamber 4 and the process inlet head 7.
  • Packing gland assemblies 44 located on the front face of front tube sheet 35, hold the process inlet/reaction tubes in position and provide a seal at these areas.
  • the process inlet head 7 is constructed from a large diameter pipe which has front tube sheet 35 on one end and has an elliptical metal head welded to the other end. Inlet nozzles 45 are installed into the body of process gas inlet head 7. Process inlet head 7 is bolted to front tube sheet 35. Steel support assemblies 46 support the reactor vessel when it is in service.
  • the ambient-temperature reactants enter reactor 1 through the process inlet nozzles 45, pass through process gas inlet head 7 into process inlet/reaction tubes 6. While flowing through cooling chamber 5, the reactants are cooled to prevent premature chlorination of ethane from occurring. As the reactants travel through the inlet/reaction tubes 6 they are preheated by the hot product gases in product outlet chamber 4.
  • the invention is applicable to any fluid (gas or liquid, including solutions of solids or slurries of solids) where components of the fluid first undergo an exothermic reaction and then an endothermic reaction, or an endothermic reaction and then an exothermic reaction.
  • the fluid should pass through the inside of inlet/reaction tubes 6 first and then between inlet/reaction tubes 6 and inner tubes 19 in order to capture all of the heat generated by the exothermic reaction for the benefit of the endothermic reaction.
  • the fluid should pass between inlet/reaction tubes 6 and inner tubes 19 first and then through inlet/reaction tubes 6 for the same reason. In either case, the endothermic reaction occurs between the tubes and the exothermic occurs inside the process inlet/reaction tubes 6.
  • the invention also contemplates the addition of a reactant to the fluid to induce the occurrence of either the exothermic or the endothermic reaction.
  • the tubes can be cooled in cooling chamber 5 with any heat transfer medium, and water is preferred for the reaction of ethane and chlorine.
  • the purpose of cooling is to prevent the exothermic reaction from occurring anywhere except in inlet/reaction tubes 6, especially near the ends of tubes 6, where the heat from the exothermic reaction can be used to promote the endothermic reaction.
  • media other than flue gas can be used as a source of heat (or cooling, if necessary) .
  • Fluid velocity can be increased by using inlet/reaction tubes 6 of small inside diameter.
  • inlet/reaction tubes 6 of small inside diameter.
  • the materials out of which the tubes and the reactor are made will depend upon the intended reactor temperature and the compounds that are present within the reactor.
  • ceramic materials are required because metals are attacked by the high-temperature chloride to form metal chlorides, which catalyze the decomposition of the hydrocarbons, resulting in coking.
  • Various ceramics such as, for example, silicon carbide, tungsten carbide, and tungsten nitride, can be used, but silicon carbide is preferred as it is readily available commercially.
  • the tubes need not be round in cross-section, but can be square or rectangular.
  • the reactor does not have to be mounted horizontally, but rather can be operated at any angle. It is only necessary that the exothermic reaction occur on one side of a heat conducting surface and the endothermic reaction occur on the opposite side and that the reacting fluid move from one side to the other side. The following examples further illustrate this invention.
  • Example 1 The apparatus shown in the drawings was used.
  • the reactor tube bundle consisted of 12 reaction tube assemblies.
  • the metal outer tube was an 8'-l 1/2" long, 2 1/2" diameter, schedule 40, stainless steel 316 finned tube.
  • the inner tube was an 8' long, 2" outside diameter, 1 5/8" inside diameter silicon carbide tube.
  • the process inlet/reaction tube was an 11' long, 1" outside diameter, 3/4" inside diameter silicon carbide tube.
  • the reaction tube assemblies were equally spaced on the tube sheet.
  • the ethane/chlorine molar ratio, the flue gas temperature and the total flow rate were varied to improve ethyl chloride cracking.
  • the initial reaction conditions included a molar feed ratio of ethane to chlorine of 2.5:1, a flue gas temperature of 900°C, and a feed flow of 500 pounds/hour.
  • the reactor pressure was maintained at 10 psig throughout the test.
  • the feed ratio was first lowered from 2.5:1 to 1.6:1 at 8-hour intervals. No sign of premature reaction was observed.
  • the total flow rate was decreased 10% at 8-hour intervals. No evidence of coking was noticed upon completion of operating at 50% of the design capacity.
  • the ethyl chloride cracking improved from 21.3% to 48.3%, as the ratio was varied from 2.5:1 to 1.6:1.
  • the cracking was further increased to 59.6%, as the total feed rate was decreased to 50% (or the retention time was doubled) .
  • the flue gas temperature was then raised from 900°C to 975°C at 25°C increments. By doing so, an additional 17.8% increase of ethyl chloride cracking was realized.
  • the final adjustments were made by lowering the ethane/chlorine ratio gradually from 1.6:1 to 1.27:1.
  • the following table summarizes the ethyl chloride cracking achieved at the various operating conditions tested.
  • the equipment down stream of the reactor was found to contain only a light dusting of coke. In the reactor, only minor amounts of carbon were found in the probable reaction initiation zone located 18 inches from the inlet.
  • Example 2 Example 1 was repeated to demonstrate the operation of the reactor at elevated pressures. At a total throughput of 500 pounds/hour and reactor pressures up to 85 psig, the premixed adiabatic reaction was successfully carried out at ethane/chlorine feed ratios as low as 1.9:1. The following table summarizes the averaged results obtained for all of the pressures at a flue gas temperature of 950°C. No signs of feed line pressure increases or premature initiation were observed.
  • Example 3 Tests were made to compare the performance of the single- pass tubular reactor and the reactor of this invention.
  • the selected reaction conditions included an ethane/chlorine molar ratio of 2:1, a flue gas temperature of 900°C, a total throughput of 500 pounds/hour, and a reactor pressure of 85 psig.
  • the single-pass tubular reactor consisted of 80 Incoloy tubes (3/4" in diameter) , and each was lined with a 1/2" outside diameter silicon carbide tube. Graphite powder was used to fill the annulus between the metal and the silicon carbide tubes. The tube bundle was secured into castable-lined headers.
  • the reactor of this invention is shown in the drawings, and detailed dimensions are given in Example 1. After the tests, it was found that the percent conversion of ethyl chloride to ethylene increased from about 24% in the single-pass tubular reactor to about 48% in the reactor of this invention. After more than 120 hours, the reactors were examined by borescope. A ring of coke less than 1/8" in thickness was discovered 22 inches from the reactor entrance and extending approximately 1/4" in all the single-pass tubular reactor tubes. On the other hand, only insignificant amounts of coke were found 18" from the inlet in the reactor of this invention.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)

Abstract

L'invention décrit un procédé visant à faire réagir un fluide soumis à une réaction exothermique suivie d'une réaction endothermique ou inversement. Un récipient est divisé en un compartiment endothermique et un compartiment exothermique par une surface d'échange thermique (6), les deux compartiments communiquant de telle sorte que le fluide s'écoule le long d'un côté de la surface (6), côté où a lieu la réaction soit endothermique soit exothermique, côté avant de s'écouler le long du côté opposé de la surface (6), côté où a lieu la réaction soit exothermique soit endothermique, puis de quitter le réacteur. La chaleur dégagée par la réaction exothermique est utilisée pour stimuler la réaction endothermique.
EP95915535A 1994-04-04 1995-04-03 Procede de reaction exothermique et endothermique Withdrawn EP0701473A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US22205094A 1994-04-04 1994-04-04
US222050 1994-04-04
PCT/US1995/004150 WO1995026811A1 (fr) 1994-04-04 1995-04-03 Procede de reaction exothermique et endothermique

Publications (1)

Publication Number Publication Date
EP0701473A1 true EP0701473A1 (fr) 1996-03-20

Family

ID=22830579

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95915535A Withdrawn EP0701473A1 (fr) 1994-04-04 1995-04-03 Procede de reaction exothermique et endothermique

Country Status (5)

Country Link
EP (1) EP0701473A1 (fr)
JP (1) JPH09501611A (fr)
CA (1) CA2164437A1 (fr)
TW (1) TW406068B (fr)
WO (1) WO1995026811A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110709490A (zh) * 2017-05-05 2020-01-17 埃克森美孚化学专利公司 用于烃加工的传热管

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI683803B (zh) 2014-11-11 2020-02-01 美商陶氏全球科技責任有限公司 由乙烷製造乙烯、偏二氯乙烯及氯化氫之方法
HUE071388T2 (hu) * 2021-05-27 2025-08-28 Basf Se Eljárás foszgén elõállítására

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1920632A (en) * 1930-08-05 1933-08-01 Koppers Co Inc Contrivance for carrying out gas reactions at high temperatures
US2850360A (en) * 1956-05-23 1958-09-02 Phillips Petroleum Co Apparatus for production of products by exothermic-endothermic heat exchange
US4355003A (en) * 1980-10-07 1982-10-19 General Signal Corporation Two pass endothermic generator
JP3124548B2 (ja) * 1990-12-06 2001-01-15 ユニヴァーシティ オブ サウザーン カリフォルニア アルケンの製造

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9526811A1 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110709490A (zh) * 2017-05-05 2020-01-17 埃克森美孚化学专利公司 用于烃加工的传热管

Also Published As

Publication number Publication date
JPH09501611A (ja) 1997-02-18
WO1995026811A1 (fr) 1995-10-12
CA2164437A1 (fr) 1995-10-12
TW406068B (en) 2000-09-21

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