WO2017146254A1 - コークス炉用プレキャストブロック耐火物 - Google Patents

コークス炉用プレキャストブロック耐火物 Download PDF

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Publication number
WO2017146254A1
WO2017146254A1 PCT/JP2017/007453 JP2017007453W WO2017146254A1 WO 2017146254 A1 WO2017146254 A1 WO 2017146254A1 JP 2017007453 W JP2017007453 W JP 2017007453W WO 2017146254 A1 WO2017146254 A1 WO 2017146254A1
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Prior art keywords
mass
component
coke oven
block refractory
less
Prior art date
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PCT/JP2017/007453
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English (en)
French (fr)
Inventor
寺島　英俊
康志 筒井
寛直 竹本
松井　泰次郎
隆志 松永
浩 北沢
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Nippon Steel Corp
Krosaki Harima Corp
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Krosaki Harima Corp
Nippon Steel and Sumitomo Metal Corp
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Application filed by Krosaki Harima Corp, Nippon Steel and Sumitomo Metal Corp filed Critical Krosaki Harima Corp
Priority to KR1020187026522A priority Critical patent/KR102098273B1/ko
Priority to ES17756688T priority patent/ES2884103T3/es
Priority to US16/079,820 priority patent/US20190055165A1/en
Priority to JP2018501824A priority patent/JP6823042B2/ja
Priority to EP17756688.2A priority patent/EP3421571B1/en
Priority to CN201780021635.1A priority patent/CN109072085B/zh
Publication of WO2017146254A1 publication Critical patent/WO2017146254A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/66—Monolithic refractories or refractory mortars, including those whether or not containing clay
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/14—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silica
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    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/6303—Inorganic additives
    • C04B35/6306—Binders based on phosphoric acids or phosphates
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    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
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    • 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
    • C10B29/00—Other details of coke ovens
    • C10B29/02—Brickwork, e.g. casings, linings, walls
    • 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
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Definitions

  • the present invention relates to a precast block refractory material suitably used in a coke oven.
  • silica bricks have been used in coke ovens.
  • silica brick it is necessary to construct a large number of bricks. Therefore, in recent years, especially in hot repair construction, construction using a siliceous precast block refractory that is easy to increase in size as compared with silica brick is often performed.
  • Such a precast block refractory is required to have hot characteristics as a structure.
  • stabilization of under-load expansion behavior and under-load shrinkage behavior (hereinafter collectively referred to as under-load expansion / contraction behavior) is required. If the expansion / contraction behavior under high temperature load is not stable (when deformation due to expansion / contraction under high temperature load is large), the resistance increases when extruding coke, which hinders operation and precast. The block refractory itself may be damaged.
  • Patent Document 1 describes a technique using fused quartz as a main raw material and Portland cement as a binder.
  • a large amount of Portland cement is used as a binder in a precast block refractory for a coke oven (for example, 2 to 10% by weight with respect to the main raw material)
  • due to the hydration reaction of Portland cement There was a problem that it contracted greatly.
  • the problem to be solved by the present invention is to provide a precast block refractory for a coke oven having high hot strength and stable expansion / contraction behavior under load at high temperature.
  • the present inventors have intensively studied to solve the above problems. For example, as described in Patent Document 1, when a large amount of cement was used as a binder, the shrinkage behavior under load at high temperature was not stabilized by the hydration reaction by cement. Moreover, when colloidal silica and sodium silicate were used as the binder, the hot strength decreased. Therefore, the present inventors do not use a large amount of cement as a binder or colloidal silica and sodium silicate as a binder in a siliceous precast block refractory for a coke oven, but as a binder component. By applying the P 2 O 5 component, it was found that the expansion / contraction behavior under load at high temperatures can be stably controlled while maintaining high hot strength.
  • the precast block refractory for a coke oven according to the present invention is characterized in that in a precast block refractory for a siliceous coke oven, the P 2 O 5 component is contained in an amount of 0.3% by mass to 2% by mass. It is.
  • the precast block refractory for a coke oven of the present invention is a precast block refractory for a coke oven having a siliceous, that is, SiO 2 component as a main component.
  • the specific content of SiO 2 component is within the range of common technical knowledge, but is preferably 65% by mass or more and 99% by mass or less, and more preferably 80% by mass or more and 99% by mass or less.
  • SiO 2 component source various siliceous raw materials such as fused silica, silica (fired silica, raw silica, etc.), fumed silica, and the like can be used. It is preferably at least mass%, more preferably at least 72 mass%. Moreover, it is preferable that the compounding quantity of a silica stone is 17 mass% or less, and the compounding quantity of a fumed silica is 0.5 to 15 mass%. That is, it is preferable that the blending amount of fused silica is 65% by mass or more and the blending amount of silica stone is 17% by mass or less from the viewpoint that the shrinkage due to dehydration during drying can be canceled.
  • the blending amount of silica may be 0% by mass.
  • the compounding quantity of a fumed silica is 0.5 to 15 mass% from the point which maintains a high hot strength.
  • the particle size of the siliceous raw material is preferably used in combination from aggregates with a top size of 5 mm to sub-micron particles in consideration of filling properties and workability.
  • under-load expansion / contraction ratio it is preferable to set the coarse particles of 1 mm or more to 25 mass% or more.
  • an alumina raw material can be used in combination.
  • the alumina material fused alumina, sintered alumina or the like can be used.
  • the SiO 2 component is less than 65% by mass, the hot strength decreases, so it is not preferable to add a large amount of the alumina raw material.
  • the P 2 O 5 component functions as a binder component as described above, but its content is 0.3% by mass or more and 2% by mass or less.
  • the pound function as the binder component is not exhibited.
  • the content of the P 2 O 5 component exceeds 2% by mass, a low melting point substance (SiO 2 —P 2 O 5 system) is excessively generated, and deformation due to shrinkage increases under a load at a high temperature. .
  • Phosphate can be used as the P 2 O 5 component source.
  • the Na 2 O component and the K 2 O component contained as impurities in the phosphate are precast blocks from the viewpoint of suppressing the formation of low melting point substances.
  • the total content of the refractory is preferably 0.5% by mass or less.
  • the blending amount of the curing accelerator is preferably 0.05% by mass or more from the viewpoint of increasing the strength at the time of curing, and maintains a high hot strength. It is preferable that it is 1.9 mass% or less from the point to do.
  • the curing accelerator include magnesia fine powder and slaked lime.
  • the precast block refractory for a coke oven of the present invention does not contain cement.
  • cement When cement is included, shrinkage under load occurs due to the hydration reaction of cement, but when cement is not included, shrinkage under load can be suppressed.
  • the precast block refractory for a coke oven of the present invention contains the above-mentioned siliceous raw material (SiO 2 component source) as a main raw material and sodium phosphate (P 2 O 5 component source) as a binder, and if necessary.
  • siliceous raw material SiO 2 component source
  • sodium phosphate P 2 O 5 component source
  • organic fibers, dispersants, curing accelerators, curing retardants, sintering aids, etc. are blended as other additives, and an appropriate amount (for example, 5 mass% to 7 mass%) of construction water is added to the obtained raw material blend. After adding, it can be obtained by a conventional precast block refractory manufacturing method of kneading, molding, curing, demolding, and drying.
  • a test piece of a precast block refractory for a coke oven obtained by blending each raw material in accordance with the raw material composition in Table 1 and adding 6.5% by mass of construction water, followed by kneading, molding, curing, demolding and drying. was used to measure the expansion / contraction behavior under load and the hot bending strength, and the overall evaluation was performed.
  • the chemical composition of the obtained test piece was analyzed.
  • the fused silica, calcined silica, raw silica, and electrofused alumina having a particle size of 5-1 mm and less than 1 mm mixed at a ratio of 6: 4 were used.
  • the fumed silica having a mean particle size of 0.5 ⁇ m was used.
  • each chemical component of the raw materials, fused silica 99.7 wt% of SiO 2 component, calcining silica is a SiO 2 component 99.5 wt%
  • raw silica is 99.7 wt% of SiO 2 component
  • fumed Silica is 96% by mass of SiO 2 component, 0.2% by mass of Na 2 O component
  • fused alumina is 100% by mass of Al 2 O 3
  • sodium phosphate is 65% by mass of P 2 O 5 component, Na 2 23% by mass of O component, 64% by mass of SiO 2 component, 22% by mass of Na 2 O component of sodium silicate, 40% by mass of SiO 2 component of colloidal silica, 24% by mass of SiO 2 component of Portland cement, magnesia
  • the fine powder was 100% by mass of the MgO component, and the slaked lime was 100% by mass of CaO.
  • the expansion / contraction behavior under load was measured in a temperature range from room temperature to 1300 ° C. in accordance with JIS R 2207-2 with a load of 0.2 MPa.
  • Excellent ( ⁇ ) when the expansion / contraction rate under load is in the range of -0.1% or more and less than 0.5%, or in the range of -0.3% or more and less than -0.1% or +0.5 % (%) Or more and less than 0.7%, good (O), -0.5% or more and less than -0.3%, or 0.7% or more and less than + 0.8%
  • the case was acceptable ( ⁇ ), less than ⁇ 0.5% or + 0.8% or more was deemed unacceptable ( ⁇ ), and acceptable ( ⁇ ) or more was deemed acceptable.
  • -(minus) means contraction under load
  • + (plus) means expansion under load.
  • Hot bending strength was measured according to JIS R 2213 at 1000 ° C. In addition, in order to make a test piece into measurement temperature, it hold
  • the overall evaluation is based on the above two evaluations, in which the case of two excellent ( ⁇ ) is excellent ( ⁇ ), the combination of excellent ( ⁇ ) and good ( ⁇ ) is good ( ⁇ ), excellent ( ⁇ ) or The combination of good ( ⁇ ) and acceptable ( ⁇ ) was permitted ( ⁇ ), the case where there was an unacceptable ( ⁇ ) was regarded as impossible ( ⁇ ), and the acceptable ( ⁇ ) or higher was regarded as acceptable.
  • Examples 1 to 15 are all precast block refractories for coke ovens within the range.
  • the overall evaluation was acceptable ( ⁇ ) or higher, and both expansion / contraction behavior under load and hot bending strength were acceptable levels.
  • Comparative Example 1 is an example in which the content of the P 2 O 5 component is low. A sufficient bond function was not obtained, and the hot bending strength was less than the acceptable level.
  • Comparative Example 2 is an example in which the content of the P 2 O 5 component is high. Since the low melting point substance (SiO 2 —P 2 O 5 ) was excessively produced, the expansion / contraction behavior under load was less than the acceptable level.
  • Comparative Example 3 is an example in which a P 2 O 5 component is applied as a binder component in a precast block refractory for a coke oven whose main component is an Al 2 O 3 component.
  • the expansion / contraction behavior under load was less than the acceptable level.
  • Comparative Example 4 is an example corresponding to the above-mentioned Patent Document 1, and is an example in which colloidal silica and sodium silicate are applied as binders. Hot bending strength was less than acceptable level.
  • Comparative Example 5 is an example using only Portland cement as a binder. The expansion / contraction behavior under load was less than the acceptable level.
  • FIG. 1 is a graph showing the expansion / contraction behavior under load from room temperature to 1300 ° C. in Example 1 and Comparative Example 5.
  • phosphate P 2 O 5 component source
  • Comparative Example 5 blended in the above shrinkage was significantly reduced from around 1000 ° C. under load.

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  • Structural Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
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  • Ceramic Products (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

本発明は高い熱間強度を有するとともに、高温時における荷重下膨縮挙動が安定なコークス炉用プレキャストブロック耐火物を提供する。すなわち、本発明は、シリカ質コークス炉用プレキャストブロック耐火物において、Ｐ２Ｏ５成分を０．３質量％以上２質量％以下含有することを特徴とするコークス炉用プレキャストブロック耐火物。

Description

コークス炉用プレキャストブロック耐火物
　本発明は、コークス炉において好適に使用されるプレキャストブロック耐火物に関する。
　従来、コークス炉においては、珪石れんががライニングされて使用されてきた。しかし、珪石れんがを用いた場合、多数のれんがを施工する必要があるため、施工に時間を要する問題があった。そこで、近年、特に熱間補修施工においては、珪石れんがに比べ大型化が容易な珪石質のプレキャストブロック耐火物を使用した施工が多く実施されている。
　このようなプレキャストブロック耐火物には、構造体としての熱間特性が求められる。特にコークス炉においては、熱間強度に加え、高温時における荷重下膨張挙動及び荷重下収縮挙動（以下、荷重下膨縮挙動と総称する）の安定化が求められる。高温での荷重下膨縮挙動が安定しない場合（高温での荷重下膨張や荷重下収縮に伴う変形が大きい場合）、コークスを押し出す際に抵抗が大きくなって操業に支障を来すとともに、プレキャストブロック耐火物自体が破損するおそれがある。
　特許文献１では、溶融石英を主原料とし、結合剤としてポルトランドセメントを用いる技術が記載されている。しかし、コークス炉用プレキャストブロック耐火物に結合剤としてポルトランドセメントを多量（例えば、主原料に対して２～１０重量％）に用いた場合、ポルトランドセメントの水和反応によって、高温での荷重下において大きく収縮するという問題があった。
　また、特許文献２では、結合剤（硬化剤）として、従来一般的に使用されているアルミナセメントに替えてコロイダルシリカ及び珪酸ソーダを使用することで、高温での荷重下収縮を抑制しようとしている。しかし、コロイダルシリカ及び珪酸ソーダを使用した場合、熱間強度が低下するという問題があった。
特開昭５６－７８４７６号公報 特開２０１３－１８９３２２号公報
　本発明が解決しようとする課題は、高い熱間強度を有するとともに、高温時における荷重下膨縮挙動が安定なコークス炉用プレキャストブロック耐火物を提供することにある。
　本発明者らは、上記課題を解決するために鋭意検討を行った。例えば、特許文献１に記載のように、結合剤としてセメントを多量に用いた場合、セメントによる水和反応によって高温下での荷重下収縮挙動が安定化しなかった。また、結合剤としてコロイダルシリカ及び珪酸ソーダを用いた場合、熱間強度が低下した。そこで、本発明者らは、シリカ質のコークス炉用プレキャストブロック耐火物において、結合剤として多量のセメントを用いたり、結合剤としてコロイダルシリカ及び珪酸ソーダを用いたりするのではなく、結合剤成分としてＰ２Ｏ５成分を適用することで、高い熱間強度を維持しつつ、高温時における荷重下膨縮挙動を安定に制御できる知見を得た。
　すなわち、本発明のコークス炉用プレキャストブロック耐火物は、シリカ質のコークス炉用プレキャストブロック耐火物において、Ｐ２Ｏ５成分を０．３質量％以上２質量％以下含有することを特徴とするものである。
　本発明によれば、高い熱間強度を発揮するとともに、高温時における荷重下膨縮挙動が安定なコークス炉用プレキャストブロック耐火物が得られる。
実施例及び比較例の荷重下膨縮挙動を示すグラフである。
　本発明のコークス炉用プレキャストブロック耐火物は、シリカ質、すなわちＳｉＯ２成分を主成分とするコークス炉用プレキャストブロック耐火物である。具体的なＳｉＯ２成分の含有量は技術常識の範囲内にあるが、６５質量％以上９９質量％以下が好ましく、８０質量％以上９９質量％以下がより好ましい。
　ＳｉＯ２成分源としては、溶融シリカ、珪石（焼成珪石、生珪石等）、ヒュームドシリカなど、各種のシリカ質原料を使用できるが、本発明では、原料配合において、溶融シリカの配合量は６５質量％以上が好ましく、より好ましくは７２質量％以上である。また、珪石の配合量は１７質量％以下、ヒュームドシリカの配合量は０．５質量％以上１５質量％以下であることが好ましい。すなわち、乾燥時の脱水による収縮を打ち消すことができる点から、溶融シリカの配合量は６５質量％以上で、珪石の配合量は１７質量％以下であることか好ましい。この場合、珪石の配合量は０質量％であってもよい。また、高い熱間強度を維持する点から、ヒュームドシリカの配合量は０．５質量％以上１５質量％以下であることが好ましい。また、シリカ質原料の粒度は、充填性及び作業性を考慮してトップサイズ５ｍｍの骨材からサブミクロンの粒子までを組み合わせて使用するのが好ましい。更に、荷重下熱膨張・収縮率（以下「荷重下膨縮率」という。）をより安定にするためには、１ｍｍ以上の粗粒を２５質量％以上とすることが好ましい。
　なお、主骨材としてシリカ質原料以外の原料としてはアルミナ質原料を併用することもできる。アルミナ質原料としては、電融アルミナ、焼結アルミナ等を用いることができる。ただし、ＳｉＯ２成分が６５質量％未満になると、熱間強度が低下するためアルミナ質原料を多量に添加するのは好ましくない。
　本発明のコークス炉用プレキャストブロック耐火物においてＰ２Ｏ５成分は、上述のとおり結合剤成分として機能するが、その含有量は０．３質量％以上２質量％以下である。Ｐ２Ｏ５成分の含有量が０．３質量％未満では結合剤成分としてのポンド機能が発揮されない。Ｐ２Ｏ５成分の含有量が２質量％を超えると、低融点物質（ＳｉＯ２－Ｐ２Ｏ５系）が過剰に生成することで、高温での荷重下において収縮に伴う変形が大きくなる。
　Ｐ２Ｏ５成分源としてはリン酸塩を使用できるが、この場合、リン酸塩に不純物として含まれるＮａ２Ｏ成分及びＫ２Ｏ成分は、低融点物質の生成を抑える点から、プレキャストブロック耐火物中の含有量として合量で０．５質量％以下であることが好ましい。
　また、本発明のコークス炉用プレキャストブロック耐火物の原料配合において、硬化促進剤の配合量は、養生時の強度を高める点から０．０５質量％以上が好ましく、かつ、高い熱間強度を維持する点から１．９質量％以下であることが好ましい。硬化促進剤としては、マグネシア微粉、消石灰等が挙げられる。
　さらに、本発明のコークス炉用プレキャストブロック耐火物は、セメントを含まないことが好ましい。セメントを含む場合、セメントの水和反応により荷重下収縮が生じるが、セメントを含まない場合、荷重下収縮を抑制することができる。
　本発明のコークス炉用プレキャストブロック耐火物は、主原料として上述のシリカ質原料（ＳｉＯ２成分源）及び結合剤としてリン酸ソーダ（Ｐ２Ｏ５成分源）を配合し、また必要に応じて、その他添加剤として有機繊維、分散剤、硬化促進剤、硬化遅延剤、焼結補助剤等を配合し、得られた原料配合物に適量（例えば５質量％～７質量％）の施工水を添加したうえで、混練、成形、養生、脱型、乾燥するという、通常のプレキャストブロック耐火物の製造方法によって得ることができる。
　表１の原料配合に従って各原料を配合し、６．５質量％の施工水を添加したうえで、混練、成形、養生、脱型、乾燥して得たコークス炉用プレキャストブロック耐火物の試験片を用いて、荷重下膨縮挙動及び熱間曲げ強度を測定し、総合評価を行った。併せて、得られた試験片の化学成分を分析した。ここで、溶融石英、焼成珪石、生珪石及び電融アルミナの粒度はそれぞれ５－１ｍｍと１ｍｍ未満とを６：４の比率で混合したものを用いた。また、ヒュームドシリカの粒度は、平均粒径０．５μｍのものを用いた。なお、原料の化学成分はそれぞれ、溶融石英はＳｉＯ２成分を９９．７質量％、焼成珪石はＳｉＯ２成分を９９．５質量％、生珪石はＳｉＯ２成分を９９．７質量％、ヒュームドシリカはＳｉＯ２成分を９６質量％、Ｎａ２Ｏ成分を０．２質量％、電融アルミナはＡｌ２Ｏ３を１００質量％、リン酸ソーダはＰ２Ｏ５成分を６５質量％、Ｎａ２Ｏ成分を２３質量％、珪酸ソーダはＳｉＯ２成分を６４質量％、Ｎａ２Ｏ成分を２２質量％、コロイダルシリカはＳｉＯ２成分を４０質量％、ポルトランドセメントはＳｉＯ２成分を２４質量％、マグネシア微粉はＭｇＯ成分を１００質量％、消石灰はＣａＯを１００質量％含有するものを用いた。
　荷重下膨縮挙動は、室温から１３００℃までの温度域においてＪＩＳ　Ｒ　２２０７－２に準拠し、０．２ＭＰａの荷重をかけて測定した。荷重下膨縮率が、－０．１％以上０．５％未満の範囲にある場合を優（◎）、－０．３％以上－０．１％未満の範囲にある場合又は＋０．５％以上＋０．７％未満の範囲にある場合を良（○）、－０．５％以上－０．３％未満の範囲にある場合又は０．７％以上＋０．８％未満の範囲にある場合を可（△）、－０．５％未満又は＋０．８％以上を不可（×）とし、可（△）以上を合格とした。なお、－（マイナス）は荷重下収縮、＋（プラス）は荷重下膨張を意味する。
　熱間曲げ強さは、１０００℃においてＪＩＳ　Ｒ　２２１３に準拠して測定した。なお、試験片を測定温度とするために炉内で１時間保持し、熱間曲げ強さを測定した。熱間曲げ強さが、１０ＭＰａ以上を優（◎）、５ＭＰａ以上１０ＭＰａ未満を良（○）、３ＭＰａ以上５ＭＰａ未満を可（△）、３ＭＰａ未満を不可（×）とし、可（△）以上を合格とした。
　そして総合評価は、上記２つの評価において、優（◎）が２つの場合を優（◎）、優（◎）と良（○）との組合せの場合を良（○）、優（◎）又は良（○）と可（△）との組合せの場合を可（△）、不可（×）がある場合を不可（×）とし、可（△）以上を合格とした。
　これらの評価結果を表１に併せて示す。
Figure JPOXMLDOC01-appb-T000001
　表１中、実施例１～１５は、いずれも範囲内にあるコークス炉用プレキャストブロック耐火物である。総合評価は可（△）以上であり、荷重下膨縮挙動、熱間曲げ強さともに、合格レベルであった。
　比較例１は、Ｐ２Ｏ５成分の含有量が低い例である。十分なボンド機能が得られず、熱間曲げ強さが合格レベルに満たなかった。一方、比較例２は、Ｐ２Ｏ５成分の含有量が高い例である。低融点物質（ＳｉＯ２－Ｐ２Ｏ５）が過剰に生成されため、荷重下膨縮挙動が合格レベルに満たなかった。
　比較例３は、Ａｌ２Ｏ３成分を主成分とするコークス炉用プレキャストブロック耐火物において、結合剤成分としてＰ２Ｏ５成分を適用した例である。荷重下膨縮挙動が合格レベルに満たなかった。
　比較例４は、上記特許文献１に相当する例で、結合剤としてコロイダルシリカ及び珪酸ソーダを適用した例である。熱間曲げ強さが合格レベルに満たなかった。
　比較例５は、結合剤としてポルトランドセメントのみを用いた例である。荷重下膨縮挙動が合格レベルに満たなかった。
　また、図１は、実施例１及び比較例５の室温から１３００℃までの荷重下膨縮挙動を示すグラフである。結合剤としてリン酸塩（Ｐ２Ｏ５成分源）を配合した本発明の範囲を満たす実施例１は荷重下膨縮挙動が安定しており、結合剤としてポルトランドセメントを多量（５質量％）に配合した比較例５は１０００℃付近から著しく荷重下収縮した。

Claims (7)

  1. 　シリカ質のコークス炉用プレキャストブロック耐火物において、Ｐ２Ｏ５成分を０．３質量％以上２質量％以下含有することを特徴とするコークス炉用プレキャストブロック耐火物。
  2. 　ＳｉＯ２成分を６５質量％以上９９質量％以下含有する請求項１に記載のコークス炉用プレキャストブロック耐火物。
  3. 　ＳｉＯ２成分を８０質量％以上９９質量％以下含有する請求項１に記載のコークス炉用プレキャストブロック耐火物。
  4. 　原料配合において、溶融シリカの配合量が６５質量％以上である請求項１から３のいずれか一項に記載のコークス炉用プレキャストブロック耐火物。
  5. 　原料配合において、珪石の配合量が１７質量％以下、ヒュームドシリカの配合量が０．５質量％以上１５質量％以下である請求項１から４のいずれか一項に記載のコークス炉用プレキャストブロック耐火物。
  6. 　　原料配合において、硬化促進剤の配合量が０．０５質量％以上１．９質量％以下である請求項１から５のいずれか一項に記載のコークス炉用プレキャストブロック耐火物。
  7. 　結合剤として、セメントを含まない請求項１から６のいずれか一項に記載のコークス炉用プレキャストブロック耐火物。
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JP2013189322A (ja) 2012-02-13 2013-09-26 Nippon Tokushu Rozai Kk 珪石質キャスタブル耐火物及び珪石質プレキャストブロック耐火物
JP2013234092A (ja) * 2012-05-09 2013-11-21 Shinagawa Refractories Co Ltd 流し込み耐火物

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JP2022077378A (ja) * 2020-11-11 2022-05-23 黒崎播磨株式会社 焼成炉用の乾式吹付材

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