US2495396A - Destructive distillation of vegetable matter with caustic and lime - Google Patents

Destructive distillation of vegetable matter with caustic and lime Download PDF

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US2495396A
US2495396A US625674A US62567445A US2495396A US 2495396 A US2495396 A US 2495396A US 625674 A US625674 A US 625674A US 62567445 A US62567445 A US 62567445A US 2495396 A US2495396 A US 2495396A
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temperature
mass
lime
caustic
drying
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Urison Jacques
Calignon Philippe De
Pingard Gustave
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PYRENCENNE DE CARBURANTS ET SO
PYRENCENNE DE CARBURANTS ET SOLVANTS Ste
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
    • C10B57/08—Non-mechanical pretreatment of the charge, e.g. desulfurization
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/78—Separation; Purification; Stabilisation; Use of additives
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10C—WORKING-UP PITCH, ASPHALT, BITUMEN, TAR; PYROLIGNEOUS ACID
    • C10C5/00—Production of pyroligneous acid distillation of wood, dry distillation of organic waste
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L9/00—Treating solid fuels to improve their combustion
    • C10L9/08—Treating solid fuels to improve their combustion by heat treatments, e.g. calcining
    • C10L9/086—Hydrothermal carbonization
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel

Definitions

  • the drawing shows a flow sheet illustrating the steps of the method.
  • Our method comprises a preliminary impregnation, a heating in an autoclave and a pyrolysis treatment, these operations being carried out as follows:
  • Impregnation is carried out with a view to causing alkalis to penetrate into the pores, and especially into the capillary network of the matter to be treated, and obtaining a mass which is homogenous at the scale of the matter cut into small parts.
  • This homogenizing of the impregnation obviously depends upon the nature of the raw material and the way in which it has been divided into small parts (by means of a straw cutter, a crusher, and so on), upon its dryness, the mechanical means used for mixing the whole, the temperature, and the pressure.
  • Impregnation must be carried out at a relatively low temperature, preferably averaging 50 C., at which temperature the vapor tensions inside the cells will oppose an admissible resistance to penetration of alkalis by dialysis.
  • the important thing concerning this impregnation is to reach a homogenous state of distribution of the liquid in the solid material without allowing disincrustation, which corresponds to a reduction of the free or "active alkali, to make substantial progress.
  • Heating is then carried out, for a relatively short time (from 1 to 4 hours for instance), in an autoclave in which the temperature of the mass is raised to l-180 C. in a very short time, for instance approximately from 10 to 15 minutes.
  • a relatively short time from 1 to 4 hours for instance
  • l-180 C. in which the temperature of the mass is raised to l-180 C. in a very short time, for instance approximately from 10 to 15 minutes.
  • This heating may be carried out with the apparatus commonly used in the manufacture of paper pulp through the soda process, and the quick rise of temperature may be obtained, under industrial conditions, by an injection of steam into the autoclave.
  • the uncondensable gases and the vapors that disengage during the heating and drying treatments, and also the uncondensable gases resulting from the pyrolysis treatment, may be used advantageously for sweeping or scavenging the free space of the pyrolysis apparatus, instead of using for this operation steam produced especially for this purpose as in known pyrolysis treatments.
  • Caustic soda is used under any physical form whatever. Water is introduced partly in admixture with wood and soda, and the amount of water necessary to give the above indicated amounts is added. The mass is left alone for 12 hours for impregnation purposes.
  • the whole is then introduced into a rotary autoclave of a capacity of 450 litres, externally heated.
  • the temperature is brought'to 180 C. in a quarter of an hour and this temperature is maintained for 3 hours.
  • the apparatus is then placed in communication with a vapor accumulator or with the pyrolysis apparatus and the pressure is allowed to drop to a value approximating atmospheric pressure.
  • the mixture of organic salts that is obtained still contains at this time about 12 percent of organic substances not scoured, with respect to the starting material.
  • the mixture contains only per cent of organic substances not scoured.
  • the whole is pyrolysed in a rotary furnace, of the continuous working type, heated from the outside (outlet temperature ranging from 500 to 600 0.).
  • the apparatus is swept by a stream of steam and vapors resulting from the heating and drying treatments.
  • Example II The following elements are intimately mixed together:
  • the mixing is pursued, at a temperature of 70 C., in a rotary apparatus, for 2 hours.
  • the mass is then introduced into a rotary autoclave.
  • the temperature is raised to 170 C. in ten minutes, by introduction oi! live steam, and this temperature is maintained for two hours.
  • the pressure is then allowed to drop to a value substantially equal to atmospheric pressure, by elimination of steam.
  • the proportion of unsecured organic substances in the mass is then about per cent of the initial matter.
  • the final residual mass. after pyrolysis is constituted by sodium and calcium carbonates, soda, lime, and a residual carbon containing a percentage of hydrogen whichdepends upon the final pyrolysis temperature;
  • This residue may be treated according to the known methods for caustificailzion of the amount of COaNaz present in the soda
  • the mixture of calcium carbonate and coal is then calcined, the residual coal adding itself to the fuel that is supplied.
  • the calcium carbonate is transformed into unslacked lime for being returned into the cycle of operations.
  • This activity depends upon the proportion of hydrogen present therein and the final temperature.
  • a method of producing liquid condensable organic-compounds from vegetable cellulosic material which comprises impregnating this cellulosic material with a caustic soda lye at a temperature relatively low, treating the impregnated material in an autoclave in the presence of caustic alkali by quickly raising the temperature of the mass up to -180 0., adding lime to the mass, drying at a temperature of 160-180 C., keeping said mass at this temperature for several hours after the end of the drying operation, and treating by pyrolysis.
  • a method of producing liquid condensable organic compounds from vegetable cellulosicmaterial which comprises impregnating this cellulosic material with a caustic soda lye, at a temperature of approximately 50 C., treating the impregnated material in an autoclave in the presence of caustic alkali by raising the temperature of the mass up to 160-180 C. in 10 to 15 minutes, by injection of live steam into the autoclave, adding lime to the mass, drying at a temperature of 160-180 C., keeping said mass at this temperature for several hours after the end of the drying Number Name Date operation, and treating by pyrolysis. 1,298,479 Drewson Mar. 25, 1918 JACQUES URISON.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
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Description

Patented Jan. 24, 1950 DESTRUCTIVE DISTILLATION OF VEGE- TABLE MATTER WITH CAUSTIC AND LIME Jacques Urison, Paris, Philippe de Calignon, Lannemeran, and Gustave Pingard, Thann, France, aslignors to Soclete Pyreneenne de Carburants ct Solvants, Paris, France, a- French corporation Application October 30, 1945, Serial No. 625,674 In France October 19, 1944 Section 1.1mm Law 690, August a, 1946 Patent expires October 19, 1964 2 Claims. (Cl. 202-34) The present invention relates to thedisintegration of celluloso-ligneous matters with a'view to obtaining liquid condensable organic compounds consisting chiefly of products of ketonic character.
The drawing shows a flow sheet illustrating the steps of the method.
Our method comprises a preliminary impregnation, a heating in an autoclave and a pyrolysis treatment, these operations being carried out as follows:
Impregnation is carried out with a view to causing alkalis to penetrate into the pores, and especially into the capillary network of the matter to be treated, and obtaining a mass which is homogenous at the scale of the matter cut into small parts. This homogenizing of the impregnation obviously depends upon the nature of the raw material and the way in which it has been divided into small parts (by means of a straw cutter, a crusher, and so on), upon its dryness, the mechanical means used for mixing the whole, the temperature, and the pressure.
Impregnation must be carried out at a relatively low temperature, preferably averaging 50 C., at which temperature the vapor tensions inside the cells will oppose an admissible resistance to penetration of alkalis by dialysis. The important thing concerning this impregnation is to reach a homogenous state of distribution of the liquid in the solid material without allowing disincrustation, which corresponds to a reduction of the free or "active alkali, to make substantial progress. v v
This impregnation must be carried out very carefully, and it is particularly delicate because the amount of liquid that is used issmall with respect to the celluloso-ligneous material (from 0.7 to 3 litres of liquid per kilogram of wood).
The methods used for this impregnation and for checking the efliciency of the homogenizing are identical to those commonly used in wood impregnation industry. For instance we may use pressure, vacuum, both alternately (for elimination of the air that may be entrapped), or any other suitable means. However, in the present case, the particularly important thing is to avoid bringing .the mixture to temperatures corresponding to a substantial disincrustation.
Heating is then carried out, for a relatively short time (from 1 to 4 hours for instance), in an autoclave in which the temperature of the mass is raised to l-180 C. in a very short time, for instance approximately from 10 to 15 minutes. In this way, we avoid keeping the mass for an appreciable time inside a zone of temperatures for which only the incrustant substances are solubilized, and we reach more rapidly the zone of temperatures for which cellulose itself is attacked, same as lignin, in suitable conditions and nea rly simultaneously.
This quick rise of the temperature can be carried out only with a mass suitably impregnated with alkali. Otherwise, that is to say in the case of a heterogeneous mixture, exothermic phenomena take place, with a. production of gases and even a spontaneous degradation of the cellulosoligneous matter analogous to carbonization.
This heating may be carried out with the apparatus commonly used in the manufacture of paper pulp through the soda process, and the quick rise of temperature may be obtained, under industrial conditions, by an injection of steam into the autoclave.
After heating, lime, either slaked or unslaked, is added to the mass and the whole is dried, preferably at a temperature of 160480 0., this temperature being maintained for some hours after the drying is completed. This prolonged drying treatment serves to produce a deeper degradation of the celluloso-ligneous matters, characterized by a reduction of the active alkalinity and of the proportion of organic substances that are not scoured.
The uncondensable gases and the vapors that disengage during the heating and drying treatments, and also the uncondensable gases resulting from the pyrolysis treatment, may be used advantageously for sweeping or scavenging the free space of the pyrolysis apparatus, instead of using for this operation steam produced especially for this purpose as in known pyrolysis treatments.
This supplementary production of steam is thus avoided or at least greatly reduced and, on the other hand, dilution of the products that are obtained, as a result of the condensation of said steam, is avoided.
We will now describe two examples of th method according to our invention:
3 Example I The following elements are intimately mixed together:
100 kgs. of oaksaw-dust 60 kgs. of caustic soda 60 kgs. of water.
Caustic soda is used under any physical form whatever. Water is introduced partly in admixture with wood and soda, and the amount of water necessary to give the above indicated amounts is added. The mass is left alone for 12 hours for impregnation purposes.
The whole is then introduced into a rotary autoclave of a capacity of 450 litres, externally heated. The temperature is brought'to 180 C. in a quarter of an hour and this temperature is maintained for 3 hours. The apparatus is then placed in communication with a vapor accumulator or with the pyrolysis apparatus and the pressure is allowed to drop to a value approximating atmospheric pressure. The mixture of organic salts that is obtained still contains at this time about 12 percent of organic substances not scoured, with respect to the starting material.
120 kgs. of slaked lime are added and the temperature is again brought to 180 C. This temperature is maintained for 2 hours, while expanding the vapor into the vapor accumulator.
After this drying treatment, the mixture contains only per cent of organic substances not scoured.
The whole is pyrolysed in a rotary furnace, of the continuous working type, heated from the outside (outlet temperature ranging from 500 to 600 0.). The apparatus is swept by a stream of steam and vapors resulting from the heating and drying treatments.
After condensation, 21 kgs. of liquid valuable products are collected, the weights corresponding to anhydrous products, to wit:
Kgs. Acetone-l-methyl alcohol 5 Light oils (flash point below 220 C.) 9 Heavy oils (flash point above 220 C.) 7
If the drying operation is dispensed with, only from 10 to kgs. of products are obtained.
Example II The following elements are intimately mixed together:
100 kgs. of vine-shoots,
50 kgs. of soda, 336 kgs. of water.
The mixing is pursued, at a temperature of 70 C., in a rotary apparatus, for 2 hours. The mass is then introduced into a rotary autoclave. The temperature is raised to 170 C. in ten minutes, by introduction oi! live steam, and this temperature is maintained for two hours. The pressure is then allowed to drop to a value substantially equal to atmospheric pressure, by elimination of steam.
The proportion of unsecured organic substances in the mass is then about per cent of the initial matter.
125 kgs. of unslaked lime are then added and the temperature is brought to 180, by external heating. This temperature is maintained for 2 hours and the pressure is caused to drop by elimcontaining:
Kgs. Acetone+methyl alcohol 6 Light oils (flash point below 220 C.) 8.5 Heavy oils (flash point above 220 C.) 7.5
These treatments are given merely by way of example and they may be modified, both concerning the operations in themselves and the particularbodies that are used, without departing from the spirit of the invention.
The final residual mass. after pyrolysis, is constituted by sodium and calcium carbonates, soda, lime, and a residual carbon containing a percentage of hydrogen whichdepends upon the final pyrolysis temperature; This residue may be treated according to the known methods for caustificailzion of the amount of COaNaz present in the soda The mixture of calcium carbonate and coal is then calcined, the residual coal adding itself to the fuel that is supplied. The calcium carbonate is transformed into unslacked lime for being returned into the cycle of operations.
The whole of the reagents that have been employed can thus be returned into the cycle with the exception of course of the losses due to the operations.
It. is also possible to recuperate the residual coal and to utilize it as activated com for instance.
This activity depends upon the proportion of hydrogen present therein and the final temperature.
In a general manner, while we have, in the above description, disclosed what we deem to be pyrolysis practical and eflicient embodiments of the present invention, it should be well understood that we do not wish to be limited thereto as there might be changes made therein without departing from the principle of th present invention as comprehended within the scope of the appended claims.
What we claim is:
1. A method of producing liquid condensable organic-compounds from vegetable cellulosic material, which comprises impregnating this cellulosic material with a caustic soda lye at a temperature relatively low, treating the impregnated material in an autoclave in the presence of caustic alkali by quickly raising the temperature of the mass up to -180 0., adding lime to the mass, drying at a temperature of 160-180 C., keeping said mass at this temperature for several hours after the end of the drying operation, and treating by pyrolysis.
2. A method of producing liquid condensable organic compounds from vegetable cellulosicmaterial, which comprises impregnating this cellulosic material with a caustic soda lye, at a temperature of approximately 50 C., treating the impregnated material in an autoclave in the presence of caustic alkali by raising the temperature of the mass up to 160-180 C. in 10 to 15 minutes, by injection of live steam into the autoclave, adding lime to the mass, drying at a temperature of 160-180 C., keeping said mass at this temperature for several hours after the end of the drying Number Name Date operation, and treating by pyrolysis. 1,298,479 Drewson Mar. 25, 1918 JACQUES URISON. 1,764,249 Erlenbach June 17, 1930 PHILIPPE n1: CALIGNON. 1,772,216 Hagglund Aug. 5, 1930 GUSTAVE PINGARD. 5 1,879,502 Rinman Sept. 27, 1932 2,177,557 Bergstrom Oct. 24, 1939 REFERENCES CITED 2,056,746 Btrupp Oct. 6, 1946 The following references are of record in the FOREIGN PATENTS me of this patent 10 Number Country Date UNITED S A S ATENTs 114,878 Australia Mar. 11, 1942 Number Name mt 424,847 Great Britain Mar. 1, 1935 1,202,479 Rinman Oct. 24, 1916

Claims (1)

1. A METHOD OF PRODUCING LIQUID CONDENSABLE ORGANIC COMPOUNDS FROM VEGETABLE CELLULOSIC MATERIAL, WHICH COMPRISES IMPREGNATING THIS CELLULOSIC MATERIAL WITH A CAUSTIC SODA LYE AT A TEMPERATURE RELATIVELY LOW, TREATING THE IMPREGNATED MATERIAL IN AN AUTOCLAVE IN THE PRESENCE OF CAUSTIC ALKALI BY QUICKLY RAISING THE TEMPERATURE OF THE MASS UP TO 160-180*C., ADDING LIME TO THE MASS, DRYING AT A TEMPERATURE OF 160-180*C., KEEPING SAID MASS AT THIS TEMPERATURE FOR SEVERAL HOURS AFTER THE END OF THE DRYING OPERATION, AND TREATING BY PYROLYSIS.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4313011A (en) * 1980-04-09 1982-01-26 Standard Oil Company (Indiana) Plant hydrocarbon recovery process
EP1852493A1 (en) * 2006-05-05 2007-11-07 BIOeCON International Holding N.V. Hydrothermal treatment of carbon-based energy carrier material

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1202479A (en) * 1915-12-11 1916-10-24 Willis A Burlingame Bottle-crate.
US1298479A (en) * 1918-07-23 1919-03-25 West Virginia Pulp & Paper Company Process for the treatment of waste liquors from soda pulp processes, &c.
US1764249A (en) * 1925-08-18 1930-06-17 Certificate of correction
US1772216A (en) * 1924-07-16 1930-08-05 Hagglund Erik Method of treating and utilizing the black liquor obtained in the sodapulp process
US1879502A (en) * 1929-07-16 1932-09-27 Rinman Erik Ludvig Method of producing valuable products from vegetable substances
GB424847A (en) * 1932-09-09 1935-03-01 Physical Chemistry Res Company Improvements in or relating to the heat treatment of oleaginous materials of vegetable or animal origin
US2056746A (en) * 1931-12-19 1936-10-06 Strupp Ernst Method for carbonization of all kinds of pulp waste lyes
US2177557A (en) * 1937-02-24 1939-10-24 Method of treating wood or lignine

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1202479A (en) * 1915-12-11 1916-10-24 Willis A Burlingame Bottle-crate.
US1298479A (en) * 1918-07-23 1919-03-25 West Virginia Pulp & Paper Company Process for the treatment of waste liquors from soda pulp processes, &c.
US1772216A (en) * 1924-07-16 1930-08-05 Hagglund Erik Method of treating and utilizing the black liquor obtained in the sodapulp process
US1764249A (en) * 1925-08-18 1930-06-17 Certificate of correction
US1879502A (en) * 1929-07-16 1932-09-27 Rinman Erik Ludvig Method of producing valuable products from vegetable substances
US2056746A (en) * 1931-12-19 1936-10-06 Strupp Ernst Method for carbonization of all kinds of pulp waste lyes
GB424847A (en) * 1932-09-09 1935-03-01 Physical Chemistry Res Company Improvements in or relating to the heat treatment of oleaginous materials of vegetable or animal origin
US2177557A (en) * 1937-02-24 1939-10-24 Method of treating wood or lignine

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4313011A (en) * 1980-04-09 1982-01-26 Standard Oil Company (Indiana) Plant hydrocarbon recovery process
EP1852493A1 (en) * 2006-05-05 2007-11-07 BIOeCON International Holding N.V. Hydrothermal treatment of carbon-based energy carrier material
US20090090046A1 (en) * 2006-05-05 2009-04-09 Bioecon International Holding B.V. Process for the conversion of biomass to liquid fuels and specialty chemicals
US8022260B2 (en) 2006-05-05 2011-09-20 Kior Inc. Process for the conversion of biomass to liquid fuels and specialty chemicals
US9000245B2 (en) 2006-05-05 2015-04-07 Kior, Inc. Process for the conversion of biomass to liquid fuels and specialty chemicals

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