WO2012177984A1 - Ensemble isolation thermique - Google Patents

Ensemble isolation thermique Download PDF

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Publication number
WO2012177984A1
WO2012177984A1 PCT/US2012/043715 US2012043715W WO2012177984A1 WO 2012177984 A1 WO2012177984 A1 WO 2012177984A1 US 2012043715 W US2012043715 W US 2012043715W WO 2012177984 A1 WO2012177984 A1 WO 2012177984A1
Authority
WO
WIPO (PCT)
Prior art keywords
grain
insulation assembly
fibers
main body
thermal conductivity
Prior art date
Application number
PCT/US2012/043715
Other languages
English (en)
Inventor
Ryan Christopher ELLOITT
Prashanth SUBRAMANIAN
Original Assignee
Graftech International Holdings Inc.
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 Graftech International Holdings Inc. filed Critical Graftech International Holdings Inc.
Priority to US14/126,596 priority Critical patent/US20140109804A1/en
Priority to KR2020147000004U priority patent/KR20140001698U/ko
Priority to CN201290000629.0U priority patent/CN203893222U/zh
Publication of WO2012177984A1 publication Critical patent/WO2012177984A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M5/00—Casings; Linings; Walls
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M5/00—Casings; Linings; Walls
    • F23M5/02—Casings; Linings; Walls characterised by the shape of the bricks or blocks used
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F27D1/0003—Linings or walls
    • F27D1/0006—Linings or walls formed from bricks or layers with a particular composition or specific characteristics
    • F27D1/0009—Comprising ceramic fibre elements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M2900/00—Special features of, or arrangements for combustion chambers
    • F23M2900/05004—Special materials for walls or lining

Definitions

  • carbon-fiber based materials are being used as insulation materials in many applications. They are particularly well suited for solar applications where high temperatures are required to melt the silicon substrate materials prior to crystallization.
  • Prior art carbon-fiber insulation assemblies for, in particular, string ribbon silicon ovens are made from a single block of carbon-fiber that is cored to form an interior volume.
  • a furnace insulation assembly includes a main body having a generally U-shaped cross-section.
  • the main body includes a pair of side walls.
  • a pair of end plates are secured to opposed ends of the main body.
  • the end plates and the main body form an interior chamber.
  • the end plates and side walls are made of a thermal insulation material formed from carbon fibers, said carbon fibers in each end plate and side wall are oriented parallel to a with-grain plane and perpendicular to an against-grain direction. The against-grain direction of the end plates and sides walls point inwardly toward the interior chamber.
  • FIG. 1 is an isometric view of a furnace insulating assembly
  • FIG. 2 is top view the furnace insulating assembly of Fig. 1 ;
  • FIG. 3 is a side view of the furnace insulating assembly of Fig. 1.
  • the thermal insulation material may be formed by, for example, mixing a reinforcement material, such as carbonized fibers, with a liquid binder, such as a sugar solution.
  • the reinforcement material includes carbon fibers, alone or in combination with other carbonized or carbonizable materials.
  • the fibers include isotropic pitch-based carbon fibers, either alone or mixed with other carbon fibers.
  • the at least 80% of the carbon fibers are isotropic pitch carbon fibers.
  • at least 95% of the carbon fibers are isotropic pitch carbon fibers.
  • 100% by weight of the carbon fibers are derived from isotropic pitch.
  • the carbon fibers may be mesophase pitch based carbon fibers.
  • the carbon fibers may be carbonized rayon fibers.
  • the carbon fibers may be carbonized PAN fibers.
  • the insulation material may include two or more different types of carbon fibers.
  • Insulation materials formed from carbon fibers according to the present method as large sheets or boards or similar rigid insulation products, have been found to exhibit sufficient strength and insulation properties to make them well suited for high temperature furnaces.
  • the term "fibers" is intended to encompass all elongate carbon-containing reinforcement materials having a length which is at least twenty times, more preferably, at least 100 times the fiber diameter (often referred to as the aspect ratio).
  • the carbon fibers preferably have an aspect ratio equal to or greater than 20: 1, more preferably, greater than 100: 1, a length of from about 2-30 mm, and a diameter of about 5-15 microns.
  • binders comprise an aqueous solution of a soluble sugar, such as a monosaccharide or disaccharide.
  • a soluble sugar such as a monosaccharide or disaccharide.
  • Exemplary sugars include sucrose, fructose, dextrose, maltose, mannose glucose, galactose, UDP-galactose, and xylose, their soluble polysaccaride equivalents, and combinations thereof.
  • the binder solution and fibers are mixed together in a ratio of about 10-40 parts by weight of binder solution to about 60-40 parts of fiber.
  • a preferred ratio is from 20-80% by weight sugar: 80-20% by weight fibers, most preferably, about 40% by weight sugar: 60% by weight fibers.
  • sucrose which has a carbon yield of about 35%
  • this ratio results in a product (after baking described herein below) having about 14% of carbonized sugar and 86% fibers by weight.
  • the carbonized sugar content of the product is between about 10% and about 20% by weight. If the carbonized sugar is too low, the integrity of the final product may be compromised. As the concentration of carbonized sugar increases, the density tends to increase, increasing the thermal conductivity of the material and rendering it less well suited for thermal insulation applications.
  • the fibers of the insulation material used in the furnace insulation assembly described herein below are not randomly aligned, but are generally randomly arranged parallel to a with-grain plane (i.e. perpendicular to the against-grain direction) in each insulation assembly piece. At least 60 percent, more advantageously 80 percent, and even more advantageously 90 percent of the fibers are substantially parallel to the with- grain plane.
  • This fiber alignment may be achieved by, for example pouring a mixture of fibers and binder into a form or mold fitted with a filter at one end and removing excess binder by gravity or a vacuum source. In this manner, the fibers build up on the filter and when the desired thickness is achieved, the fibers and remaining binder are removed as a pre-form.
  • light pressure may be applied to the pre-form, either during filtration or during a subsequent heating step, although excessive pressure can compromise the insulative properties of the finished product.
  • the pressure, if applied does not result in a final density of the insulation product of more than about 0.5 g/cm 3 .
  • the pre-form may be heated to a temperature of about 200°C to 300°C to drive off water from the binder solution. It is also contemplated that the filtering step may be eliminated and that the mixture simply be heated, first to drive off excess water and later in the heating process, to convert the remaining sugar to a polymeric form.
  • the pre-form is then carbonized at a final temperature of about 900°C to about 2000°C in an inert (non-oxidizing) atmosphere, such as argon to remove all (or substantially all) oxygen and hydrogen and produce a carbonized article in the desired shape.
  • the carbonization temperature is selected according to the end use of the casting and is generally above the highest temperature to which the casting is to be subjected in use. This reduces the chance for out-gassing during use.
  • the resulting carbonized article comprises primarily carbon (i.e. , at least 95% carbon, more preferably, at least 98% carbon, most preferably, greater than 99.5% carbon) and has a density of typically less than about 1 g/cm 3 , preferably less than 0.5 g/cm 3 , more preferably less than 0.3 g/cm 3 , which is suitable for thermal insulation.
  • the article is sectioned or machined to an appropriate size as will be described hereinbelow.
  • the insulation articles produced by the above method are well suited to use at temperatures of 1500-2000°C, or higher.
  • the insulation material has a low density of 0.1 to 0.40 g/cm 3 , more preferably, from 0.15-0.25 g/cm 3 , and a thermal conductivity in the against-grain direction (i.e. perpendicular to the plane of orientation of the fibers) of less than about 0.4 W/m°K, more preferably less than about 0.3 W/m°K and even more preferably less than about 0.2 W/m°K.
  • the thermal conductivity may be from between about 0.15 to about 0.2 W/m°K. (All thermal conductivities are measured in air at 25°C, unless otherwise noted).
  • the thermal conductivity in the with-grain direction is relatively higher than the against-grain direction.
  • the ratio of against-grain thermal conductivity to with-grain thermal conductivity is less that about .6. In other embodiments, the ratio of against-grain thermal conductivity to with-grain thermal conductivity is less than about .5. In other embodiments, the ratio of against- grain thermal conductivity to with-grain thermal conductivity is less than about .42. In other embodiments the ratio of against-grain thermal conductivity to with-grain thermal conductivity is from between about .2 and about .8.
  • the ratio of against-grain thermal conductivity to with-grain thermal conductivity is from between about .3 and about .5.
  • the with-grain thermal conductivity may be greater than about 0.3 W/m°K.
  • the with-grain thermal conductivity may be from between about 0.3 to about 1 W/m°K.
  • the with-grain thermal conductivity may be from between about 0.3 to about 0.5 W/m°K.
  • Insulation assembly 10 includes three separate parts including a main body 12 and a pair of end plates 14a and 14b.
  • main body 12 is in the form of an elongated rectangle having a longitudinal length approximately two times the height and width thereof. It should be appreciated however that the body 12 length shown and described is merely exemplary and may be shorter or longer depending on the application.
  • the body portion 12 includes generally U-shaped cross-section that forms a chamber 16. As can be seen from the figures, chamber 16 may include various surface features, notches or channels as may be required for the heating and substrate elements (not shown) that are received therein.
  • a first end 18 of the main body 12 is open and a second end 20 includes a wall section 22.
  • the with-grain plane of main body 12 runs along the length and height thereof.
  • This configuration is advantageous because the thermal conductivity described hereinabove of the insulating material is relatively lower in the against-grain direction (labeled the Z direction in the figures). Therefore, the longitudinal side walls 24 are oriented to provide maximum insulative effect. Put another way, the side walls 24 include two opposed major surfaces and the Z direction is oriented perpendicular to the major surfaces.
  • End plates 14a and 14b are secured to opposed ends of main body 12 respectively. End plates 14 may be secured to main body 12 via any appropriate means including, but not limited to, adhesives, mechanical fasteners or combinations thereof.
  • the with- grain plane of end plates 14 runs along the width and height of the insulation assembly. As discussed above, this configuration is advantageous because the end plates 14 are oriented to provide maximum insulative effect. In this manner, the side walls 24 and end walls 14 are oriented so that the against- grain direction of each part points inwardly toward interior chamber 16. Thus, the maximum insulative property of the insulation material is obtained.
  • the above described insulation assembly is particularly applicable for use in a string ribbon puller for the solar industry. However, the assembly may be used in other solar and silicon based applications requiring improved energy efficiency. It should further be appreciated that, though the above described embodiment disclosed a three- piece insulation assembly, more than three pieces might be employed, for a separate piece might be used for each exterior facing wall and arranged such that the against-grain direction for each wall points inwardly toward the chamber.

Abstract

L'invention porte sur un ensemble isolation de four qui comprend un corps principal ayant une section transversale généralement en forme de U. Le corps principal comprend une paire de parois latérales. Une paire de plaques d'extrémité sont fixées à des extrémités opposées du corps principal. Les plaques d'extrémité et le corps principal forment une chambre intérieure. Les plaques d'extrémité et les parois latérales sont fabriquées en un matériau d'isolation thermique formé à partir de fibres de carbone, lesdites fibres de carbone dans chaque plaque d'extrémité et paroi latérale étant orientées contre des points de direction de grain vers l'intérieur vers la chambre intérieure.
PCT/US2012/043715 2011-06-24 2012-06-22 Ensemble isolation thermique WO2012177984A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US14/126,596 US20140109804A1 (en) 2011-06-24 2012-06-22 Thermal Insulation Assembly
KR2020147000004U KR20140001698U (ko) 2011-06-24 2012-06-22 단열 조립체
CN201290000629.0U CN203893222U (zh) 2011-06-24 2012-06-22 炉具隔热组件

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201161500983P 2011-06-24 2011-06-24
US61/500,983 2011-06-24

Publications (1)

Publication Number Publication Date
WO2012177984A1 true WO2012177984A1 (fr) 2012-12-27

Family

ID=47422965

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2012/043715 WO2012177984A1 (fr) 2011-06-24 2012-06-22 Ensemble isolation thermique

Country Status (4)

Country Link
US (1) US20140109804A1 (fr)
KR (1) KR20140001698U (fr)
CN (1) CN203893222U (fr)
WO (1) WO2012177984A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015009389A1 (fr) * 2013-07-15 2015-01-22 Graftech International Holdings Inc. Dispositif utilisable en vue de la production de cristaux de silicium

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4394766A (en) * 1981-08-03 1983-07-19 Great Lakes Carbon Corporation Graphitization system method and apparatus
US5705106A (en) * 1992-12-22 1998-01-06 Aerospatiale Societe Nationale Industrielle Heat-insulating structural carbon material and process for producing heat-insulating structural carbon material
US7150837B2 (en) * 2002-06-28 2006-12-19 Ucar Carbon Company, Inc. Isotropic pitch-based materials for thermal insulation

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3990203A (en) * 1976-03-29 1976-11-09 Greaves James R Insulated ceramic fiber panels for portable high temperature chambers
US5010706A (en) * 1986-10-17 1991-04-30 Thermal Ceramics, Inc. Insulation and the provision thereof
US20040076810A1 (en) * 2002-10-17 2004-04-22 Ucar Carbon Company Inc. Composite high temperature insulator
JP4106395B2 (ja) * 2003-12-18 2008-06-25 島根県 金属基炭素繊維複合材料およびその製造方法
US9718447B2 (en) * 2009-02-02 2017-08-01 Goodrich Corporation Thermal management composite heat shield
US8537553B2 (en) * 2011-02-14 2013-09-17 Futurewei Technologies, Inc. Devices having anisotropic conductivity heatsinks, and methods of making thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4394766A (en) * 1981-08-03 1983-07-19 Great Lakes Carbon Corporation Graphitization system method and apparatus
US5705106A (en) * 1992-12-22 1998-01-06 Aerospatiale Societe Nationale Industrielle Heat-insulating structural carbon material and process for producing heat-insulating structural carbon material
US7150837B2 (en) * 2002-06-28 2006-12-19 Ucar Carbon Company, Inc. Isotropic pitch-based materials for thermal insulation

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015009389A1 (fr) * 2013-07-15 2015-01-22 Graftech International Holdings Inc. Dispositif utilisable en vue de la production de cristaux de silicium

Also Published As

Publication number Publication date
KR20140001698U (ko) 2014-03-21
CN203893222U (zh) 2014-10-22
US20140109804A1 (en) 2014-04-24

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