SYNTHESIS OF SILICON CARBIDE BY FUEL-RICH COMBUSTION IN CERAMIC SURFACE BURNER

陶瓷表面燃烧器富燃料燃烧合成碳化硅

• 批准号: 10650743
• 负责人: ITAYA Yoshinori
• 金额: $ 2.24万
• 依托单位: NAGOYA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650743/
• 关键词: COMBUSTION SYNSESIS; FUEL-RICH COMBUSTION; POROUS CERAMIC BURNER; COMBUSTION BY OXYGEN; SILICON CARBIDE; REACTION KINETICS; 予混合燃焼; ハニカム; メタン-空気燃料; 素反応モデル解析

The porous ceramic surface burner, in which flame is formed along the surface on a porous ceramic plate, has flammability limit in wide region of equivalence ratio. If the combustion of a methane-oxygen mixture at high temperature can take place under a fairly fuel-rich equivalence ratio, silicon dioxide may be converted to silicon carbide. In the present study, an application of the surface burner to the combustion synthesis of silicon carbide was proposed and the possibility was investigated fundamentally. The following knowledge was obtained : 1) The surface burner was assembled by using ceramic honeycomb and flashback was not observed from the test of flammability limit. 2) The fuel-rich combustion of the burner achieved up to 3.0 in equivalence ratio, but soot generation became significant. 3) The thin flame attached on the surface of honeycomb in less equivalence ratio than 1.5 while the length of the flame attached on the surface of honeycomb in less equivalence ratio than 1.5 w … More hile the length of the flame was enlarged with elevation of the equivalence ratio beyond 1.5. 4) The chemical reaction kinetic model was analyzed on the basis of the elementary reactions with 31 species. The analytical result showed that the composition and temperature satisfied the condition required for the carbonizing reaction of silicon dioxide in the higher equivalence ratio than 2.0. 5) A piece of quartz glass was examined to synthesize a film of silicon carbide on the slab in the fuel-rich flame of the burner. However the production was not detected by XRD analysis because the sample could not maintain sufficiently high temperature necessary for the reaction due to large radiant heat loss compared with the combustion heat load. The fact means that a key factor for realizing this process should be to reduce the radiant heat loss compared with the combustion heat load. The fact means that a key factor for realizing should be to reduce the radiant heat loss from slabs and maintain temperature. Less

多孔陶瓷表面燃烧器，其中火焰沿着多孔陶瓷板的表面形成，在宽当量比范围内具有可燃极限。如果甲烷-氧气混合物在高温下的燃烧可以在燃料相当丰富的当量比下进行，则二氧化硅可以转化为碳化硅。在本研究中，提出了表面燃烧器在碳化硅燃烧合成中的应用，并从根本上探讨了其可能性。得到如下认识： 1)采用陶瓷蜂窝组装表面燃烧器，在可燃极限测试中未观察到回火现象。 2）燃烧器富燃料燃烧当量比达到3.0，但烟尘产生量显着。 3）当量比小于1.5时，火焰附着在蜂窝表面较细，而当量比小于1.5时，火焰长度附着在蜂窝表面……超过1.5时，火焰长度随着当量比的升高而增大。 4)在31种基元反应的基础上分析了化学反应动力学模型。分析结果表明，其组成和温度满足当量比大于2.0的二氧化硅碳化反应所需的条件。 5)检查一块石英玻璃在燃烧器的富燃料火焰中在板坯上合成碳化硅薄膜。然而，由于与燃烧热负荷相比，辐射热损失较大，因此样品无法维持反应所需的足够高的温度，因此 XRD 分析未检测到生成物。事实上，实现这一过程的关键因素应该是相对于燃烧热负荷减少辐射热损失。事实上，实现这一目标的关键因素应该是减少板坯的辐射热损失并保持温度。较少的