EP0256186B1 - Slag removal system for a solid fuels gasification reactor - Google Patents

Slag removal system for a solid fuels gasification reactor Download PDF

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Publication number
EP0256186B1
EP0256186B1 EP86306344A EP86306344A EP0256186B1 EP 0256186 B1 EP0256186 B1 EP 0256186B1 EP 86306344 A EP86306344 A EP 86306344A EP 86306344 A EP86306344 A EP 86306344A EP 0256186 B1 EP0256186 B1 EP 0256186B1
Authority
EP
European Patent Office
Prior art keywords
slurry
slag
conduit
reactor
water
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 - Lifetime
Application number
EP86306344A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0256186A1 (en
Inventor
M. Dale Mayes
William P. White
Frank A. Ruiz
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.)
Dow Chemical Co
Original Assignee
Dow Chemical Co
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
Priority to CA000515369A priority Critical patent/CA1320642C/en
Priority to IN642/MAS/86A priority patent/IN167905B/en
Priority to EP86306344A priority patent/EP0256186B1/en
Priority to ZA866011A priority patent/ZA866011B/xx
Priority to DE8686306344T priority patent/DE3686720T2/de
Application filed by Dow Chemical Co filed Critical Dow Chemical Co
Priority to AU61707/86A priority patent/AU582267B2/en
Priority to CN86105182A priority patent/CN1016071B/zh
Publication of EP0256186A1 publication Critical patent/EP0256186A1/en
Application granted granted Critical
Publication of EP0256186B1 publication Critical patent/EP0256186B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
    • C10J3/46—Gasification of granular or pulverulent flues in suspension
    • C10J3/48—Apparatus; Plants
    • C10J3/52—Ash-removing devices
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
    • C10J3/46—Gasification of granular or pulverulent flues in suspension
    • C10J3/48—Apparatus; Plants
    • C10J3/52—Ash-removing devices
    • C10J3/526—Ash-removing devices for entrained flow gasifiers
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
    • C10J2300/0913—Carbonaceous raw material
    • C10J2300/093—Coal
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
    • C10J2300/0913—Carbonaceous raw material
    • C10J2300/0943—Coke
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
    • C10J2300/0913—Carbonaceous raw material
    • C10J2300/0946—Waste, e.g. MSW, tires, glass, tar sand, peat, paper, lignite, oil shale
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/16—Integration of gasification processes with another plant or parts within the plant
    • C10J2300/1625—Integration of gasification processes with another plant or parts within the plant with solids treatment
    • C10J2300/1628—Ash post-treatment

Definitions

  • This invention concerns the gasification of solid carbonaceous materials such as coke, coal, or lignite. More particularly, this invention concerns discharging slag and/or heavy ash from a solid fuels gasification reactor.
  • solid fuels such as coke, coal or lignite can be ground to a fine particulate size and mixed with oil or water to form the feed stream for a gasification reactor which is designed to make a useful synthetic gas product.
  • a large quantity of molten slag that requires disposal is formed in the reactor.
  • the waste slag or heavy ash generated in a solid fuels gasification process consists of solidified inorganic matter and a small amount of unreacted carbon.
  • this slag is discharged from the bottom of the reactor an an elevated temperature and pressure in the form of a water slurry.
  • the slurry being discharged may be at a temperature as high as between 150 and 350°F (65 and 177°C) and at a pressure as high as between 100 and 500 pounds per square inch (690 to 3450 kPa).
  • Prior art apparatus and methods generally include crushing the slag to reduce the size of the slag particles, using lockhoppers to reduce the pressure, and flashing the water from the slag in order to further lower the temperature and pressure of the slurry being discharged.
  • US Patent 4472171 discloses a high pressure gasifier for powdered coal, with a discharge device for the resulting slurry, comprising a floating piston which is moveable in a cylindrical chamber, and wherein the pressure of the slurry to be discharged is applied alternately to the two sides of the piston.
  • the present invention provides an improved apparatus and process for the continuous, uninterrupted removal of a slag/water slurry from a pressurized solid fuels gasification reactor, the apparatus comprising: at least one pressurized crusher for reducing the particle size of the slag solids, said crusher being connected to the slag discharge end of the reactor and characterized in that the apparatus comprises a depressurizing system which includes a conduit through which the slag/water slurry continuously flows, said conduit being connected to the discharge end of the crusher, and at least one restriction element to restrict the continuous kinetic fluid flow of the slag/water slurry through the conduit, said restriction element being disposed within the conduit and having an opening, the diameter of which is less than that of the conduit, said element causing a reduction in the pressure of the slurry at the discharge end of the depressurizing system to a level substantially below the pressure of the reactor.
  • a depressurizing system which includes a conduit through which the slag/water slurry continuously flows, said conduit being connected to the discharge end of
  • the final discharge pressure of the slurry may be essentially atmospheric or either higher or lower than atmospheric if the slurry is transferred to other apparatus.
  • the present apparatus may also include additional crushers and flow restriction elements in a series configuration to further reduce the particle size of the slag and pressure drop from the reactor.
  • the flow restriction elements provide a restriction to the fluid flow of the slurry in the passageway transporting the slurry from the reactor, thereby causing a pressure drop accross the element under continuous kinetic fluid flow conditions.
  • the present process for discharging a slag/water slurry from a coal gasification reactor includes: first comminuting or crushing the slag solids in the slurry discharged from the reactor to reduce the particle size thereof, said slurry being discharged from the reactor at a pressure substantially equal to the reactor pressure; and passing the slurry through a depressurizing system which includes a conduit through which the slurry flows continuously and at least one restriction element to restrict the continuous kinetic fluid flow of the slurry and thereby reduce the pressure of the slurry at the discharge end of the depressuring system to a level substantially below that of the pressure of the reactor said restriction element being disposed within the conduit and having an opening the diameter of which is less than that of the conduit.
  • the process may also include additional steps of comminuting or crushing the solids in the slurry, and restricting the fluid flow of the slurry, to further reduce the size of the slag and lower the exit pressure of the slurry from the depressurizing system.
  • the present method further provides for injecting and mixing water with the slurry at a controlled rate of flow after the slag solids have been comminuted, thereby cooling the slurry and providing for variable flow and pressure control of the slurry through the depressurizing system of the reactor.
  • the present system provides for the continuous flow removal of slag from a pressurized gasification reactor with a reduced risk of plugging as compared to intermittent removal provided by the known lockhopper systems.
  • a slag removal apparatus 10 is illustrated by Figure 1 for communuting, cooling, and depressurizing the slag/water slurry from the bottom of a coal-gasification reactor 1.
  • the waste discharge from reactor 1 comprises a solid residue which can be characterized as either a solidified inorganic residue or heavy ash.
  • the slag discharge is combined with water in reactor 1 to form a slurry.
  • the reactor 1 is operated under conditions of temperature, pressure, and concentrations generally well-known and practiced in the art for converting coke, lignite, or coal into gaseous fuel.
  • the temperature at the discharge end of the reactor 1 is between 150 and 350°F (65 and 177°C) and the pressure is between 100 and 500 pounds per square inch (690 and 3450 kPa).
  • the reactor 1 is operated continuously; and the comminution, cooling, and depressurization of the reactor slag/water slurry are carried out as a continuous process.
  • the slag/water slurry is discharged from the reactor 1 through a first conduit 2 to a primary crusher 3.
  • the crusher 3 is provided with a housing capable of withstanding the full pressure at the discharge end of the reactor 1.
  • the conduit 2 and crusher 3 are connected together by flanges 4.
  • the partially comminuted slag from the primary crusher 3 is discharged to a secondary crusher 3a, where the slag is further comminuted.
  • the crusher 3a is also provided with a housing which, like the housing for the primary crusher 3, is capable of withstanding the full operating pressure at the discharge end of the reactor 1.
  • Crushers 3 and 3a are connected together by flanges 4a.
  • the comminuted slag is then discharged as a slurry from the secondary crusher 3a to a second conduit 5.
  • the conduit 5 is connected to the crusher 3a by flanges 4b and 4c.
  • Flow through the conduit 5 may be controlled by a first valve 5a. Downstream of the valve 5a, water is introduced into conduit 5 from conduit 6 through valve 6a.
  • the slag/water slurry then passes through a series of restriction elements 7 in the conduit 5.
  • Valves 5a and 6a regulate and control the flow rate of the water and of the slag/water slurry.
  • the slurry stream may then be discharged from the last restriction element 7 at substantially atmospheric pressure.
  • conduit 6 beneficially eliminate the necessity for flashing the water from the slurry to reduce the temperature and pressure of the slurry stream after it exits from the depressurizing system.
  • the use of the valve 6a to control the flow rate of the water added to the slag stream overcomes the need for providing a downstream valve in conduit 5 to control the slurry flow rate. Since the rate of mechanical wear in such a valve would be much higher due to the abrasive characteristics of the slurry as compared to the wear caused only by water, this method of injecting water into the slurry to provide flow control is highly beneficial, economical, and advantageous.
  • the introduction of water into conduit 5 also provides both a positive safety and most beneficial means of preventing plugging of conduit 5 with the slag.
  • element 20 is similar to the reduced diameter pipe element 7 shown in Figure 1, in that element 20 includes a wear-resistant plate 8 through which a reduced diameter orifice 8a is provided for restricting the flow of the slag/water slurry.
  • the plate is held in position by flanges 4d in conduit 5.
  • the plate 8 may also be formed as a laminated structure in which the up-stream layer is a highly abrasion-resistant material such as silicon carbide, tungsten carbide, alumina, or wear-resistant metal or ceramic material.
  • an abrasion-resistant liner for conduit 5 may also be provided if the conduit is not directly formed of an abrasion-resistant material.
  • FIG. 3 illustrates a restriction element 30 which includes a frustra-conical support 9 which is held in place by flanges 4e in conduit 5, and which in turn holds a wear-resistant cone-shaped liner 9a with an orifice 9b in place to receive the slag/water slurry.
  • Conduit 5 on both sides of element 30 also has a wear-resistant liner insert 11.
  • Figure 4 illustrates still another useful restriction element 40 which includes a restriction plug 12 with an orifice 12a held in place by a wear-resistant liner insert 13 in conduit 5.
  • the restriction element 40 is further held in place by an obstruction, not shown, in a down-stream flange of conduit 5.
  • Plug 12 is beneficially molded in one piece from a hard abrasion-resistant ceramic material such as alumina.
  • the restricted opening or orifices of all the above restriction elements may be formed with any desired cross-sectional shape.
  • an orifice having a round, oval, square, triangular or rectangular shape may be used successfully in conduit 5.
  • the most beneficial shape is a round cross-section with the orifice having a relative diameter of ten to thirty percent of the diameter of the conduit in which it is disposed.
  • the size of orifices of different shapes should be selected to provide about the same relative orifice to conduit size ratio.
  • the materials of construction for the slag removal apparatus 10 may be selected from known materials that will stand up under the temperatures and pressures previously noted, with the preferred material being carbon steel. Also in areas where severe mechanical wear is expected from the slag/water slurry, the high wear-resistant materials noted above should be used.
  • the primary and secondary crushers 3 and 3a are beneficially rotary crushers which include rotor plates and breaker plates, not shown. Such crushers are well-known in the art.
  • the slag is comminuted in the primary crusher 3 to a maximum dimension of about two and one-half inches (63.5 mm), and in the secondary crusher 3a to a dimension of between one-eight of an inch and one inch (3.2 and 25 mm).
  • the present combination of slag crushers, restriction elements and means for introducting water at or down-stream from the crushers provides a continuous, reliable, controllable apparatus for removal of slag from a solid fuels gasification reactor which has a far less tendency to be plugged by slag than other known slag removal systems.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Processing Of Solid Wastes (AREA)
  • Disintegrating Or Milling (AREA)
  • Crushing And Grinding (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
EP86306344A 1986-08-06 1986-08-15 Slag removal system for a solid fuels gasification reactor Expired - Lifetime EP0256186B1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
CA000515369A CA1320642C (en) 1986-08-06 1986-08-06 Slag removal system for a solid fuels gasification reactor
IN642/MAS/86A IN167905B (enrdf_load_stackoverflow) 1986-08-06 1986-08-11
ZA866011A ZA866011B (enrdf_load_stackoverflow) 1986-08-06 1986-08-15
DE8686306344T DE3686720T2 (de) 1986-08-06 1986-08-15 Schlacken-austragesystem fuer einen vergasungsreaktor fuer feste brennstoffe.
EP86306344A EP0256186B1 (en) 1986-08-06 1986-08-15 Slag removal system for a solid fuels gasification reactor
AU61707/86A AU582267B2 (en) 1986-08-06 1986-08-21 Slag removal system for a solid fuels gasification reactor
CN86105182A CN1016071B (zh) 1986-08-06 1986-08-22 固体燃料气化反应器用的渣滓排除装置

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA000515369A CA1320642C (en) 1986-08-06 1986-08-06 Slag removal system for a solid fuels gasification reactor
EP86306344A EP0256186B1 (en) 1986-08-06 1986-08-15 Slag removal system for a solid fuels gasification reactor

Publications (2)

Publication Number Publication Date
EP0256186A1 EP0256186A1 (en) 1988-02-24
EP0256186B1 true EP0256186B1 (en) 1992-09-09

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ID=42651236

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86306344A Expired - Lifetime EP0256186B1 (en) 1986-08-06 1986-08-15 Slag removal system for a solid fuels gasification reactor

Country Status (7)

Country Link
EP (1) EP0256186B1 (enrdf_load_stackoverflow)
CN (1) CN1016071B (enrdf_load_stackoverflow)
AU (1) AU582267B2 (enrdf_load_stackoverflow)
CA (1) CA1320642C (enrdf_load_stackoverflow)
DE (1) DE3686720T2 (enrdf_load_stackoverflow)
IN (1) IN167905B (enrdf_load_stackoverflow)
ZA (1) ZA866011B (enrdf_load_stackoverflow)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3714915A1 (de) * 1987-05-05 1988-11-24 Shell Int Research Verfahren und vorrichtung fuer die herstellung von synthesegas
JP5682623B2 (ja) 2010-03-31 2015-03-11 日立金属株式会社 スラリーの再生方法、希土類系焼結磁石の製造方法およびスラリーの再生装置
JP5743093B2 (ja) 2011-09-07 2015-07-01 三菱日立パワーシステムズ株式会社 スラグ排出システム、ガス化装置、およびガス化発電装置
US9222040B2 (en) 2012-06-07 2015-12-29 General Electric Company System and method for slurry handling
CN102732325A (zh) * 2012-07-06 2012-10-17 东南大学 一种高压高温炉渣风水共冷排渣装置
US9181046B2 (en) 2012-12-04 2015-11-10 General Electric Company System and method to supply a solid feedstock to a solids feeder
US10018416B2 (en) 2012-12-04 2018-07-10 General Electric Company System and method for removal of liquid from a solids flow
US9156631B2 (en) 2012-12-04 2015-10-13 General Electric Company Multi-stage solids feeder system and method
WO2014143168A1 (en) 2013-03-15 2014-09-18 Koenig Mark E Outlet tube for a material transfer system
GB2511890B8 (en) * 2013-03-15 2018-09-05 Koenig Mark Outlet tube for a material transfer system
US10190065B2 (en) 2013-03-15 2019-01-29 Mark E. Koenig Feed delivery system and method for gasifier
US9702372B2 (en) 2013-12-11 2017-07-11 General Electric Company System and method for continuous solids slurry depressurization
US9784121B2 (en) 2013-12-11 2017-10-10 General Electric Company System and method for continuous solids slurry depressurization
CN111978993B (zh) * 2020-07-17 2022-01-07 新奥科技发展有限公司 一种减压装置及排焦系统
CN115028344B (zh) * 2022-07-14 2024-10-29 咸宁南玻光电玻璃有限公司 耳池放料回收装置及其应用

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB801803A (en) * 1954-06-05 1958-09-24 Svein Berger Evensen An automatic closing device for doors
GB801103A (en) * 1955-12-03 1958-09-10 Kohlenscheidungs Gmbh Gas producer or furnace with continuous discharge of molten residue
ZA751337B (en) * 1974-03-18 1976-02-25 Lummus Co Ash removal system in coal or coke gasification
US4472171A (en) * 1983-05-31 1984-09-18 Texaco Development Corporation Method and system for removing slag

Also Published As

Publication number Publication date
AU582267B2 (en) 1989-03-16
CA1320642C (en) 1993-07-27
DE3686720T2 (de) 1993-01-28
CN1016071B (zh) 1992-04-01
EP0256186A1 (en) 1988-02-24
CN86105182A (zh) 1988-03-02
IN167905B (enrdf_load_stackoverflow) 1991-01-05
AU6170786A (en) 1988-02-25
ZA866011B (enrdf_load_stackoverflow) 1988-02-11
DE3686720D1 (de) 1992-10-15

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