EP0051623B1 - Kohlenaufbereitung - Google Patents

Kohlenaufbereitung Download PDF

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Publication number
EP0051623B1
EP0051623B1 EP81901210A EP81901210A EP0051623B1 EP 0051623 B1 EP0051623 B1 EP 0051623B1 EP 81901210 A EP81901210 A EP 81901210A EP 81901210 A EP81901210 A EP 81901210A EP 0051623 B1 EP0051623 B1 EP 0051623B1
Authority
EP
European Patent Office
Prior art keywords
coal
agglomerates
steam
particles
hydrocarbon liquid
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.)
Expired
Application number
EP81901210A
Other languages
English (en)
French (fr)
Other versions
EP0051623A4 (de
EP0051623A1 (de
Inventor
David E. Mainwaring
Charles U. Jones
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.)
BP Australia Pty Ltd
Broken Hill Pty Co Ltd
Original Assignee
BP Australia Pty Ltd
Broken Hill Pty Co Ltd
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 BP Australia Pty Ltd, Broken Hill Pty Co Ltd filed Critical BP Australia Pty Ltd
Priority to AT81901210T priority Critical patent/ATE9593T1/de
Publication of EP0051623A1 publication Critical patent/EP0051623A1/de
Publication of EP0051623A4 publication Critical patent/EP0051623A4/de
Application granted granted Critical
Publication of EP0051623B1 publication Critical patent/EP0051623B1/de
Expired legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
    • B03B9/00—General arrangement of separating plant, e.g. flow sheets
    • B03B9/005—General arrangement of separating plant, e.g. flow sheets specially adapted for coal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
    • B03D3/00—Differential sedimentation
    • B03D3/06—Flocculation
    • 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

Definitions

  • This invention relates to an improved method of preparing mined coal for its end use and in particular to the preparation of mined coal as a feedstock for power generating stations.
  • Co-pending patent application 55574/80 relates to a process of deashing coal which comprises crushing mined coal into small sized particles, subjecting said mined coal to wetting with a hydrocarbon liquid and forming agglomerates of carbonaceous material in said coal, separating said carbonaceous agglomerates from non carbonaceous material present in said coal, subjecting said carbonaceous agglomerates to vapour separation treatment in the absence of oxidizing gases to separate the hydrocarbon liquid from said carbonaceous material to produce the deashed coal product and recycling said hydrocarbon liquid for use in wetting said mined coal.
  • the present invention provides a method of separating an agglomerated mixture of coal particles and a liquid hydrocarbon to form finely divided coal and recover the hydrocarbon liquid which comprises disintegrating said agglomerates and subsequently and/or simultaneously subjecting agglomerates to vapourphase separation in the presence of steam and in the absence of oxidizing gases to recover the liquid hydrocarbon from the finely divided coal particles.
  • all of said agglomerates are above 1 mm in size, said steam temperature is above 200°C, the residence time of the coal particles in the steam stripping zone is less than 5 seconds and at least 70% of the coal product comprises particles less than 0.3 mm and final product oil content less than 2.5%.
  • Comminution of the agglomerates prior to the vapour phase separation may be carried out in any conventional comminution device.
  • the agglomerates are subjected to initial attrition to reduce the particle size of the agglomerates and subsequently passing said agglomerates into the path of a high velocity stream of steam to further reduce the coal particle size and to separate such hydrocarbon liquid into a vapour phase.
  • the velocity and the internal shape of the particle entrainer may be chosen to be sufficient to disintegrate the agglomerates.
  • said agglomerates are passed into a high velocity stream of steam to simultaneously separate the hydrocarbon liquid and to form the finely divided coal particles.
  • the system at a commercial scale would still utilize underwater storage (tanks or ponds) of the coal-oil agglomeration stage product and the slurry reclamation and de-watering systems as specified in the prior process of 55574/80.
  • This feed material would be then fed to the front end of a conveying pipe to which superheated steam would also be fed.
  • An initial short section of the conveying pipe would be used to achieve disintegration of the feed and the remainder to accomplish removal of the oil from the coal surfaces to the gas stream.
  • Disengagement of the solids from the dry vapours would be achieved in a high efficiency cyclone system with the solids discharging to a storage hopper prior to independent delivery of the fuel to the burners. This then could be performed in lean or dense or phases in steam or air.
  • the cyclone overhead vapours are then totally condensed, and the hydrocarbon liquids separated and returned to the agglomeration system.
  • Control of the residual oil level of the particulate coal product may be achieved in this system by control of the inlet steam temperature and steam to oil mass ratio both of which strongly influence the kinetics of mass transfer of the oil from the coal surfaces. Further, the product is steam blanketed throughout the stripping and storage systems and no oxidation of the particulate material or spontaneous combustion prior to the burners need be risked.
  • the present invention provides a method of preparing mined coal for use as fuel in steam generation comprising crushing mined coal into small sized particles subjecting said mined coal to wetting with a hydrocarbon liquid and forming agglomerates of carbonaceous material, separating said carbonaceous material from non carbonaceous material present in said coal and subsequently disintegrating said agglomerates and simultaneously and/or subsequently subjecting the disintegrated agglomerates to a vapour phase separation in the presence of steam and in the absence of oxidizing gases to recover said hydrocarbon liquid and form finely divided coal particles as steam generating fuel.
  • a plant for preparing and delivering fuel to a steam generator comprising a storage for a slurry of crushed, mined coal, apparatus for agglomerating said coal with a hydrocarbon liquid, separation means for separating said coal agglomerates from the water phase of said slurry, comminution apparatus to disintegrate said agglomerates, means to dispense said disintegrated agglomerates into a stripper through which steam is passed at vapour phase separating conditions to vaporize said hydrocarbon liquid from said coal particles, separation apparatus to separate said coal particles and recover said hydrocarbon liquid and means to convey said coal particles to said steam generator.
  • said comminution apparatus is omitted, and the velocity of steam and the internal shape of the particle entrainer which constitutes said stripper is selected to disintegrate said agglomerate.
  • FIG. 1 An example of one configuration of such a system at the pilot plant or commercial scale is shown in Figure 1.
  • unstripped agglomerates are recovered from a storage pond or tank 3 and pumped to a set of dewatering screens 4.
  • Dewatered agglomerates are then fed to a small hopper/feeder 5 at the front end of the stripper and waste water is pumped out through line 6.
  • Agglomerates fed to the stripping tube 7 are picket up by the conveying steam 12 and pass through an initial short length of pipe constructed internally to disintegrate the agglomerate material as it passes through. The remainder of the tube provides the additional residence time for oil vapourisation.
  • Stripped solids then pass with the steam and hydrocarbon vapours to a cyclone 8 where the solids are disengaged.
  • a sample of coal was treated to the oil agglomeration process as set out in pending application 55574/80.
  • the agglomerating oil used was a light gas oil with a boiling range of 240-340°C.
  • the ash content was reduced form 26% on the feed coal (DCB, dry coal basis), to 13.6% on the agglomerate (DCB).
  • the particle size of the agglomerates is given in Table 1 and the particle size of the coal particles within the agglomerates is shown in Table 2.
  • the oil and water contents of the agglomerates were 12.3% (total agglomerate basis - TAB) and 4.8% respectively.
  • a continuous steam stripping rig was utilized in these examples.
  • the rig is shown in Figure 2.
  • Saturated steam generated in boiler 21 at 791 kPa (100 psig) passes through a pressure reducing valve 22 dropping the pressure into the 0-27,6 kPa (0-4 psig) range.
  • the steam then passes into a superheater 23 and from the superheater through a jet 24 into an entrainer 25.
  • Agglomerates are also fed from Hopper 27 to the entrainer 25 through a rotary valve 28. Breakdown of the agglomerates occurs under action of the steam jet within the entrainer 25 and the particles are then transported through a carrier pipe 29 of approximately 1 m in length within which oil is vapourized from the agglomerate surface.
  • the stripped solids are separated from the steam and oil in a cyclone 30.
  • the steam and oil are passed through a water cooled condenser 31 from which the oil and water can be separated as distinct liquid phases.
  • the agglomerates Prior to feeding to the steam stripping unit, the agglomerates were part broken up in a rod mill and screened to a top size of 1.18 mm.
  • TAB residual oil levels
  • Evaporation of hydrocarbon from the films on coal particles and of the water droplets is accomplished by contacting the disintegrated agglomerate material with superheated steam.
  • the model monitors heat and mass transfer as a function of time thus determining the rates of hydrocarbon stripping from the coal particles, water evaporation and degree of solids heating. Requires mass ratios of steam to hydrocarbon and the initial degree of superheat in the steam are predicted.
  • the physical system represented by the model is that of pneumatic conveying of agglomerate material in a steam atmosphere. A number of stages can be identified in the system.
  • the model considers (i) and (ii) to be instantaneous and examines stripping as a function of contact time with steam i.e. operations (iii) and (iv) are included. Condensation is not included in the model.
  • the stripping model was run with the following input conditions.
  • Particular size after disintegration ranged from 6 to 100 microns.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)

Claims (8)

1. Verfahren zum Trennen eines agglomerierten Gemisches aus Kohleteilchen und einem flüssigen Kohlenwasserstoff zum Bilden fein verteilter Kohle und Rückgewinnen des Kohlenwasserstoffes, welches Zerkleinern der Agglomerate und anschließende und/oder gleichzeitige DampfphasenAbscheidung der Agglomerate in Anwesenheit von Dampf und in Abwesenheit oxidierender Gase umfasst, um den flüssigen Kohlenwasserstoff aus den fein verteilten Kohleteilchen rückzugewinnen.
2. Verfahren nach Anspruch 1, bei welchem die Agglomerate zunächst einer mechanischen Abtragung unterworfen werden, um die Teilchengröße der Agglomerate zu vermindern, und anschließend die Agglomerate in die Bahn eines Hochgeschwindigkeits-Dampfstromes gebracht werden, um die Kohleteilchengröße weiter zu verringern und den flüssigen Kohlenwasserstoff in Dampfphase abzuscheiden.
3. Verfahren nach Anspruch 1, bei welchem die Agglomerate in einen Hochgeschwindigkeits-Dampfstrom zum gleichzeitigen Abscheiden der flüssigen Kohlenwasserstoffe zur Bildung feinverteilter Kohleteilchen und zum Abziehen des flüssigen Kohlenwasserstoffs gebracht werden.
4. Verfahren nach einem der Ansprüche 1-3, bei welchem alle Agglomerate eine Größe von mehr als 1 mm haben, die Dampftemperatur oberhalb von 200°C liegt, die Verweilzeit der Kohleteilchen in der Dampf-Abziehzone weniger als 5 Sekunden beträgt und mindestens 70% des Kohleproduktes Teilchen einer Große von weniger als 0,3 mm und einen Endgehalt an Öl von weniger als 2,5% aufweisen.
5. Verfahren zum Aufbereiten von Grubenkohle zur Verwendung als Brennstoff bei der Dampferzeugung, wobei die Grubenkohle in Teilchen kleiner Große gebrochen oder gemahlen und danach mit einem flüssigen Kohlenwasserstoff befeuchtet wird und Agglomerate kohlenstoffhaltigen Materials gebildet werden, worauf das kohlenstoffhaltige Material und das in der Kohle enthaltene nicht kohlenstoffhaltige Material getrennt werden und anschließend die Agglomerate zerkleinert und gleichzeitig und/oder nachfolgend einer Dampfphasenabscheidung in Anwesenheit von Dampf und in Abwesenheit von oxidierenden Gasen unterzogen werden, um den flüssigen Kohlenwasserstoff rückzugewinnen und fein verteilte Kohleteilchen als dampferzeugenden Brennstoff zu bilden.
6. Verfahren nach Anspruch 5, bei welchem die Zerkleinerung und die Dampfphasenabscheidung wie in einem der Ansprüche 2 bis 4 beansprucht erfolgen.
7. Anlage zum Aufbereiten und Speisen von Brennstoff zu einem Dampferzeuger mit einem Speicher für einen Schlamm aus gebrochener bzw. gemahlener Grubenkohle, einer Vorrichtung zum Agglomerieren dieser Kohlen mit einem flüssigen Kohlenwasserstoff, Trennmitteln zum Trennen der Kohleagglomerate von der Wasserphase des Schlamms, einer Zerkleinerungsvorrichtung zum Zerkleinern der Agglomerate, Mitteln zum Abgeben der zerkleinerten Agglomerate in eine Abziehvorrichtung, durch welche Dampf unter Dampfphasen-Abscheidebedingungen geleitet wird, um den flüssigen Kohlenwasserstoff aus den Kohleteilchen zu vaporisieren, einer Abscheidevorrichtung zum Abscheiden der Kohleteilchen und zum Rückgewinnen des flüssigen Kohlenwasserstoffs und Mitteln zum Fördern oder Kohleteilchen zum Dampferzeuger.
8. Anlage des Anspruch 7, bei welcher die Zerkleinerungsvorrichtung weggelassen ist und die Dampfgeschwindigkeit und die innere Gestaltung des Teilchenförderers, welche die Abziehvorrichtung bildet, so gewählt sind, daß die Agglomerate zerkleinert werden.
EP81901210A 1980-05-13 1981-05-12 Kohlenaufbereitung Expired EP0051623B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81901210T ATE9593T1 (de) 1980-05-13 1981-05-12 Kohlenaufbereitung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPE351580 1980-05-13
AU3515/80 1980-05-13

Publications (3)

Publication Number Publication Date
EP0051623A1 EP0051623A1 (de) 1982-05-19
EP0051623A4 EP0051623A4 (de) 1982-09-15
EP0051623B1 true EP0051623B1 (de) 1984-09-26

Family

ID=3768528

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81901210A Expired EP0051623B1 (de) 1980-05-13 1981-05-12 Kohlenaufbereitung

Country Status (5)

Country Link
EP (1) EP0051623B1 (de)
JP (1) JPS57500929A (de)
CA (1) CA1158439A (de)
WO (1) WO1981003337A1 (de)
ZA (1) ZA813167B (de)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2121433B (en) * 1982-05-14 1985-12-11 American Minechem Corp Converting a carbonaceous material into an improved feedstock
AU2282183A (en) * 1982-12-24 1984-06-28 Bp Australia Limited Method of preparing a slurry feed for combustion by agglomeration of coal particles
EP1752209A1 (de) * 2005-08-12 2007-02-14 Ferring International Center S.A. Verfahren und Vorrichtung zur Zerkleinerung von Granulaten
WO2007020508A1 (en) * 2005-08-12 2007-02-22 Ferring International Center S.A. Method and device for dividing granules

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2769537A (en) * 1951-11-06 1956-11-06 Bergwerksverband Gmbh Production of high-grade products, especially fuels, from raw material containing pit coal or brown coal
US3051644A (en) * 1959-07-01 1962-08-28 Texaco Inc Method for recovering oil from oil shale
GB1300499A (en) * 1970-06-04 1972-12-20 Ishikawajima Harima Heavy Ind Stave cooling device
US3863327A (en) * 1972-12-27 1975-02-04 Roland Arthur Legate Method of lining metal pipes
EP0016536A1 (de) * 1979-02-23 1980-10-01 Bp Australia Limited Verfahren zur Trennung von Kohlenwasserstoffflüssigkeiten von einem festen kohlenstoffhaltigen Material, mit dem sie gemischt sind, und Verwendung dieses Verfahrens zur Entaschung von Kohle

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4008054A (en) * 1975-01-10 1977-02-15 Consolidation Coal Company Process for making low-sulfur and low-ash fuels
JPS52121007A (en) * 1976-04-05 1977-10-12 Mitsubishi Heavy Ind Ltd Pretreatment of coal of lower leachability
AU514167B2 (en) * 1977-03-12 1981-01-29 Kobe Steel Limited Thermal dehydration of brown coal
US4224038A (en) * 1978-06-19 1980-09-23 Atlantic Richfield Company Process for removing sulfur from coal
US4270927A (en) * 1979-06-19 1981-06-02 Atlantic Richfield Company Process for removal of sulfur and ash from coal
AU530284B2 (en) * 1979-07-20 1983-07-07 Mitsui Kozan Chemicals Co. Ltd. Treating water containing coal

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2769537A (en) * 1951-11-06 1956-11-06 Bergwerksverband Gmbh Production of high-grade products, especially fuels, from raw material containing pit coal or brown coal
US3051644A (en) * 1959-07-01 1962-08-28 Texaco Inc Method for recovering oil from oil shale
GB1300499A (en) * 1970-06-04 1972-12-20 Ishikawajima Harima Heavy Ind Stave cooling device
US3863327A (en) * 1972-12-27 1975-02-04 Roland Arthur Legate Method of lining metal pipes
EP0016536A1 (de) * 1979-02-23 1980-10-01 Bp Australia Limited Verfahren zur Trennung von Kohlenwasserstoffflüssigkeiten von einem festen kohlenstoffhaltigen Material, mit dem sie gemischt sind, und Verwendung dieses Verfahrens zur Entaschung von Kohle

Also Published As

Publication number Publication date
ZA813167B (en) 1982-06-30
JPS57500929A (de) 1982-05-27
EP0051623A4 (de) 1982-09-15
WO1981003337A1 (en) 1981-11-26
EP0051623A1 (de) 1982-05-19
CA1158439A (en) 1983-12-13

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