Production of methanol

• US 3,920,717 A
• Filed: 03/26/1973
• Issued: 11/18/1975
• Est. Priority Date: 03/26/1973
• Status: Expired due to Term

• Current Assignee: Charles P. Marion
• Original Assignee: Charles P. Marion
• Inventors: Marion, Charles P.
• Primary Examiner(s): Mars, Howard T.
• Application Number:
  US05/345,144
• Time in Patent Office: 967 Days
• Field of Search: 252/373,449.5
• US Class Current: 518/703
• CPC Class Codes: C07C 29/1518 one step being the formation of initial mixture of carbon oxides and hydrogen for synthesis
• CPC Class Codes: C07C 29/154 containing copper, silver, gold, or compounds thereof
• CPC Class Codes: C07C 31/04 Methanol
• CPC Class Codes: C10J 2300/093 Coal
• CPC Class Codes: C10J 2300/0946 Waste, e.g. MSW, tires, glass, tar sand, peat, paper, lignite, oil shale
• CPC Class Codes: C10J 2300/0956 Air or oxygen enriched air
• CPC Class Codes: C10J 2300/0959 Oxygen
• CPC Class Codes: C10J 2300/0976 as steam
• CPC Class Codes: C10J 2300/1665 to alcohols, e.g. methanol or ethanol
• CPC Class Codes: C10J 2300/1807 Recycle loops, e.g. gas, solids, heating medium, water
• CPC Class Codes: C10J 2300/1846 Partial oxidation, i.e. injection of air or oxygen only
• CPC Class Codes: C10J 3/485 Entrained flow gasifiers
• CPC Class Codes: C10J 3/74 Construction of shells or jackets
• CPC Class Codes: C10J 3/78 High-pressure apparatus
• CPC Class Codes: C10J 3/86 combined with waste-heat boilers
• CPC Class Codes: C10K 3/04 reducing the carbon monoxide content , e.g. water-gas shift [WGS]
• CPC Class Codes: F25J 3/0223 H2/CO mixtures, i.e. synthesis gas; Water gas or shifted synthesis gas production of carbon monoxide containing gas in general C01B32/40, C10J, C10K; production of hydrogen containing gas C01B3/00
• CPC Class Codes: F25J 3/0285 of argon
• CPC Class Codes: F25J 3/04018 of main feed air
• CPC Class Codes: F25J 3/04036 of oxygen
• CPC Class Codes: F25J 3/04121 : Steam turbine as the prime mechanical driver
• CPC Class Codes: F25J 3/04539 : for the H2/CO synthesis by partial oxidation or oxygen consuming reforming processes of fuels
• CPC Class Codes: F25J 3/04587 : for the NH3 synthesis, e.g. for adjusting the H2/N2 ratio
• CPC Class Codes: Y02E 50/30 : Fuel from waste, e.g. synthetic alcohol or diesel

Abstract

A continuous process for producing methanol including the steps of producing synthesis gas i.e. H2 + CO by the partial oxidation of a hydrocarbonaceous feed in a free-flow non-catalytic synthesis gas generator, adjusting the mole ratio (H2/CO) of the process gas stream to a value in the range of about greater than 2 to 12 by noncatalytic thermal direct water-gas shift, cooling the process gas stream by indirect heat exchange with water to produce steam for use in the process, purifying the gas stream preferably with a portion of the methanol product, catalytically reacting the purified synthesis gas stream under methanol producing conditions, and separating methanol from liquid impurities. All steps are preferably carried out at a pressure which is substantially that in the synthesis gas generator less ordinary line drop. Optionally, a portion of the liquid impurities e.g. dimethylether, water, and mixed alcohols, are introduced into the synthesis gas generator to reduce the specific consumption of free-oxygen gas and to increase the yield of synthesis gas.

Claims

1. A CONTINUOUS PROCESS FOR PRODUCING METHANOL COMPRISING:

(1) REACTING A HYDROCARBONACEOUS OR OXYGENATED HYDROCARBONACEOUS FEEDSTOCK BY PARTIAL OXIDATION WITH A FREE-OXYGEN CONTAINING GAS AND OPTIONALLY IN THE PRESENCE OF A TEMPERAUTURE MODERATOR SELECTED FROM THE GROUP CONSISTING OF H2O, CO2, N2, FLUE GAS, COOLED OFF GAS FROM AN ORE-REDUCTION ZONE, A PORTION OF COOLED AND RECYCLED EFFLUENT GAS FROM THE SYNTHESIS GAS GENERATOR, AND MIXTURES THEREOF AT AN AUTOGENOUS TEMPERATURE IN THE RANGE OF ABOUT 1600* TO 3500*F AND A PRESSURE IN THE RANGE OF ABOUT 20 TO 450 ATMOSPHERES IN THE REACTION ZONE OF A FREE-FLOW UNPACKED NONCATALYTIC SYNTHESIS GAS GENERATOR TO PRODUCE N EFFLUENT GAS STREAM COMPRISING H2, CO, CO2, AND H2O AND IN MOLE % H2S. 0-2;

COS, 0-02;

CH4, 0.2-15;

A, 0-2.0;

N2, 0-60;

AND ENTRAINED SOLIDS AND ASH;

(2) REMOVING ENTRAINED SOLIDS AND ASH FROM THE EFFLUENT GAS STREAM FROM (1) AND INTRODUCING SAID GAS STREAM IN ADMIXTURE WITH ABOUT 0.1 TO 2.5 MOLES OF SUPPLEMENTAL STEAM PER MOLE OF EFFLUENT GAS STREAM INTO A SEPARATE FREE-FLOW UNPACKED REACTION ZONE AT A PRESSURE SUBSTANTIALLY THAT IN SAID SYNTHESIS GAS GENERATOR LESS ORDINARY LINE DROP AND AT A TEMPERATURE OF AT LEAST 1500*F AND REACTING TOGETHER H2O AND CO IN SAID MIXTURE WITHOUT A CATALYST THEREBY INCREASING THE MOLE RATIO (H2/CO) OF THE GAS STREAM TO A VALUE IN THE RANGE OF ABOUT GREATER THAN 2.0 TO 12;

(3) COOLING THE EFFLUENT GAS STREAM FROM (2) BY INDIRECT HEAT EXCHANGE WITH WATER THREBY PRODUCING STEAM, OPTIONALLY INTRODUCING A FIRST PORTION OF SAID STEAM INTO THE SYNTHESIS GAS GENERATOR IN (1) AS THE H2O TEMPERATURE MODERATOR, OPTIONALLY MIXING A SECOND PORTION OF SAID STEAM WITH THE EFFLUENT STREAM IN STEP (2) AS SAID SUPPLEMETAL STEAM, AND OPTIONALLY INTRODUCING OTHER PORTIONS OF SAID STEAM INTO AT LEAST ONE STEAM TURBINE IN THE SYSTEM AS THE WORKING FLUID;

(4) INTRODUCING THE EFFLUENT GAS STREAM FROM (3) INTO A GAS PURIFICATION ZONE AND SEPARATING THEREFROM A PROCESS GAS STREAM COMPRISING PRINCIPALL Y H2 AND CO;

(5) MIXING 0 TO 10 MOLES OF A COMPRESSED RECYCLE STREAM OF UNCOVERTED GASES PRODUCED SUBSEQUENTLY IN A METHANOL REACTION ZONE WITH EACH MOLE OF PROCESS GAS STREAM FROM (4) TO PRODUCE AMETHANOL FEED GAS MIXTURE;

(6) PREHEATING THE METHANOL FEED GAS MIXTURE FROM (5) TO A TEMPERATURE IN THE RANGE OF ABOUT 400* TO 750*F BY INDIRECT HEAT EXCHANGE WITH AN EFFLUENT STREAM LEAVING SAID METHANOL REACTION ZONE;

(7) INTRODUCING THE PREHEATED FEED GAS STREAM FROM (6) INTO SAID METHANOL REACTION ZONE, AND REACTING TOGETHER H2 AND CO WHILE IN CONTCT WITH A METHANOL CATALYST AT SUBSTANTIALLY THE SAME PRESSURE AS THAT IN SAID SYNTHESIS GAS GENERATOR LESS ORDINARY DROP IN THE LINE AND EQUIPMENT TO PRODUCE SAID EFFLUENT STREAM FROM THE METHANOL REACTION ZONE COMPRISING METHANOL, UNCOVERTED GASES. H2O, AND LIQUID IMPURITIES SELECTED FROM THE GROUP CONSISTING OF DIMETHYLETHER, MIXED ALCOHOLS, ALDEHYDES, KETONES, AND MIXTURES THEREOF, (8) SEPARATING A SEPARATE STREAM OF SAID UNCONVERTED GASES FROM THE EFFLUENT STREAM FOM THE METHANOL REACTION ZONE;

(9) CCOMPRESSING AT LEAST A PORTION OF THE STREAM OF UNCOVERTED GASGS FROM (8) AND INTRODUCING SAID STREAM INTO (5) AS SAID COMPRESSED STREAM OF UNCOVERTED GASES;

(10) SEPARATING SAID LIQUID IMPURITIES AND A SEPARATE STREAM OF METHANOL FROM THE EFFLUENT STREAM FROM THE METHANOL REACTION ZONE;

AND (11) INTRODCING AT LEAST A PORTION OF SAID LIQUID IMPURITIES INTO SAID SYNTHESIS GAS GENERATOR IN (1) AS AT LEAST A PORTION OF SAID FEED STOCK.

2. The process of claim 1 wherein the methanol catalyst in step (4) is selected from the group consisting of zinc oxide, copper oxide, and mixtures thereof plus a promoter selected from the group of oxides consisting of chromium, magnesium, aluminum, and mixtures thereof.

3. The process of claim 1 wherein said free-oxygen containing gas is substantially pure oxygen (95 mole percent O2 or more).

4. The process of claim 1 wherein said hydrocarbonaceous feedstock is selected from the group consisting of liquefied petroleum gas, petroleum distillates and residua, naphtha, gas oil, residual fuel, reduced crude, whole crude, asphalt, coal tar, coal oil, shale oil, tar-sand oil, and pumpable slurries of coal, particulate carbon, and petroleum coke in water or in a liquid hydrocarbon fuel, and mixtures thereof.

5. The process of claim 1 wherein said hydrocarbonaceous feedstock is selected from the group consisting of methane, propane, natural gas, water-gas, coke-oven gas, synthesis gas, refinery gas, and mixtures thereof.

6. The process of claim 1 wherein said hydrocarbonaceous oxygenated feedstock are organic materials selected from the group consisting of carbohydrates, cellulosic materials, aldehydes, organic acids, alcohols, ketones, oxygenated fuel oil, waste liquids and by-products from chemical processes containing oxygenated hydrocarbonaceous organic materials, and mixtures thereof.

7. The process of claim 1 wherein the process gas stream from step (4) also contains from about 1 to 12 mole percent CO2.

8. The process of claim 1 wherein at least a portion of the unconverted gases from step (8) are recycled to the synthesis gas generator of step (1).

9. The process of claim 1 with the added step of mixing a stream of supplemental hydrogen rich gas with the process gas stream from (4) to increase the mole ratio (H2/CO).

10. The process of claim 1 wherein the process gas stream from step (4) comprises principally H2, CO, and CO2, and the mole ratio (H2/2CO + 3CO2) is less than 1.05 and greater than 1.01.

11. The process of claim 1 where in the methanol reaction zone in step (7) the pressure is in the range of about 20 to 110 atmospheres, the temperature is in the range of about 400* to 700*F., and the catalyst consists of a mixture of copper, zinc, and chromium oxides with the following ranges of atomic percentages;

copper, 90 to 20;

zinc, 8 to 60; and

chromium, 2 to 30.

12. The process of claim 1 where the pressure in the methanol reaction zone in step (7) is in the range of about above 200 to 400 atmospheres, the temperature is in the range of about 570* to 750*F., and the catalyst comprises approximately in weight percent, zinc oxide 89 and chromium oxide 11.

13. The process of claim 1 where a portion of the methanol from step (8) is introduced into the gas purification zone of step (4) as make-up solvent for selective absorption of at least a portion of the gaseous impurities in the effluent gas stream from (3).

14. The process of claim 1 where in step (7) the methanol catalyst comprises principally copper-aluminum-zinc, the pressure in the methanol reaction zone is in the range of about 40 to 100 atmospheres, and the space velocity is in the range of about 10, 000 to 50,000 standard cubic feet per cubic foot of catalyst per hour.

15. The process of claim 1 where in step (5) 3 to 8 moles of said compressed recycle stream of unconverted gases are mixed with each mole of process gas stream from step (4).

16. The process of claim 1 wherein the methanol feed gas stream reacted in step (7) includes CO2 in the range of greater than 8-less than 12 mole %.

17. A continuous process for producing methanol comprising:

(1) reacting a sulfur-containing hydrocarbonaceous feedstock by partial oxidation with substantially pure oxygen in the presence of H2O as a temperature moderator at an autogenous temperature in the range of about 1600* to 3500*F and a pressure in the range of about 205 to 450 atmospheres in the reaction zone of a free-flow unpacked noncatalytic synthesis gas generator to produce an effluent gas stream comprising H2, CO, CO2, and H2O and in mole % H2S, 0-2;

COS, 0-0.2;

CH4, 0.2-15;

A, 0-2.0;

N2, 0-60; and

entrained particulate carbon and other solids;

(2) quenching all of the effluent gas stream from step (1) in a quench zone with H2O thereby cooling said gas stream to a temperature in the range of about 400* to 900*F and removing entrained particulate carbon and other solids while vaporizing into said gas stream about 0.1 to 2.5 of supplemental H2O per mole of effluent gas stream from (1), and reheating the gas stream from said quench zone to a temperature greater than 1500*F. (3) introducing the effluent gas stream from (2) into a separate free-flow unpacked reaction zone at a pressure substantially that in said synthesis gas generator less ordinary line drop and at a temperature in the range of about 1500* to 2800*F and reacting together H2O and CO in said gas stream without a catalyst thereby increasing the mole ratio (H2/CO) of the gas stream to a value in the range of about greater than 2.0 to 12;

(4) cooling the effluent gas stream from (3) by indirect heat exchange with water thereby producing steam, introducing a first portion of said steam into the synthesis gas generator in (1) as the H2O temperature moderator, and introducing separate portions of said steam into at least one steam turbine in the system as the working fluid;

(5) introducing the effluent gas stream from (4) into a gas purification zone at substantially the same pressure as that in said synthesis gas generator less ordinary line drop, and obtaining therefrom a process gas stream comprising principally H2 CO; and

CO;

(6) mixing 3 to 8 moles of compressed recycle stream of unconverted gases produced subsequently in a methanol reaction zone with each mole of process gas stream from (5) to produce a methanol feed gas mixture;

(7) preheating the methanol feed gas mixture from (6) to a temperature in the range of about 400* to 750*F by indirect heat exchange with an effluent stream leaving said methanol reaction zone;

(8) introducing the preheated feed gas stream from (7) into said methanol reaction zone, and reacting together H2 and CO while in contact with a methanol catalyst comprising zinc and chromium oxides with 0.5 to 1.5 chromium atoms per atom of zinc and a promoter selected from the group consisting of magnesium, iron, and manganese at a temperature in the range of about 570* to 750*F and a pressure in the range of about 200 to 400 atmospheres and at substantially the same pressure as that in said synthesis gas generator less ordinary drop in the line and equipment to produce said effluent stream from the methanol reaction zone comprising methanol, unconverted gases, H2O and liquid impurities selected from the group consisting of dimethylether, isobutanol, ethanol, acetone, aldehydes and mixtures thereof;

(9) separating a stream of said unconverted gases from the effluent stream from the methanol reaction zone;

(10) compressing at least a portion of the stream of unconverted gases from (9) and introducing said stream into (6) as sAid compressed stream of unconverted gases; and

(11) separating said liquid impurities and a separate stream of methanol from the effluent stream from the methanol reaction zone; and

(12) introducing at least a portion of said liquid impurities into said synthesis gas generator in (1) as at least a portion of said hydrocarbonaceous feedstock.

18. In the continuous process of manufacturing methanol from a gas mixture principally comprising H2, and CO prepared by the partial oxidation of a hydrocarbonaceous or oxygenated hydrocarbonaceous fuel with substantially pure oxygen in the presence of H2O at an autogenous temperature in the range of about 1600* to 3500*F in the reaction zone of a free-flow unpacked noncatalytic synthesis gas generator to produce an effluent gas stream principally comprising H2 and CO;

reacting H2O and CO in the process gas stream by water-gas shift reaction to produce a feed gas stream comprising H2 and CO; and

reacting said feed gas stream in a catalytic methanol reaction zone to produce an effluent stream comprising methanol;

the improvement which comprises reacting said hydrocarbonaceous or oxygenated hydrocarbonaceous fuel in said synthesis gas generator at a pressure to the range of about 20 to 450 atmospheres to produce an effluent gas stream comprising H2, CO, CO2, and H2O, and in mole % H2S, 0-2;

COS 0-0.2;

CH4, 0.2-15;

A, 0-2.0;

N2, 0-60; and

entrained solids;

removing said entrained solids;

introducing about 0.1 to 2.5 moles of supplemental steam per mole of effluent gas and adjusting the H2/CO mole ratio of said process gas stream by noncatalytic water-gas shift reaction between H2O and CO contained therein at a temperature in the range of about 1500* to 2800*F;

removing impurities from the process gas stream to produce a feedstream principally comprising H2 and CO, and containing CO2 in the amount of about 2 to 12 mole percent;

introducing said feedstream into said catalytic methanol reaction zone at a temperature in the range of about 400* to 750*F and a pressure in the range of about 20 to 450 atm. to produce an effluent stream comprising methanol, unconverted gases, H2O, and organic liquids containing combined oxygen selected from the group consisting of dimethyl ether, mixed alcohols, aldehydes, ketones, and mixtures thereof;

separating a stream of said unconverted gases, a stream of said organic liquids containing combined oxygen, and a stream of methanol, from said effluent stream of materials produced in said methanol reaction zone; and

feeding a stream of said unconverted gases or a separate stream of said organic liquids containing combined oxygen, or both of said streams into said synthesis gas generator as a portion of the feed; and

wherein the pressure in all steps in the process through the methanol reaction zone is substantially the same as that in the synthesis gas generator, less ordinary line drop.