Development of High corrosion - resistant Materials for Advanced Waste Incineration Plants

先进垃圾焚烧厂高耐腐蚀材料的开发

• 批准号: 12555195
• 负责人: HARA Motoi
• 金额: $ 2.88万
• 依托单位: Akita University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12555195/
• 关键词: Advanced waste incineration plant; Head exchanger material; Hot corrosion; Molten salt corrosion; Nickel - chromium alloy; Nickel - chromium - molybdenum alloy; 1Nickel - chromium - silicon alloy; ガス腐食; ニッケル

The object of this study was the development of high corrosion-resistant materials for the heat exchange of the exhaust gas in the advanced waste incineration plants. As the metallic materials, which can be resistant to the exhaust gas environment, are limited to Ni-base alloys, pure Ni, binary Ni-Cr alloys, and ternary Ni-Cr alloys containing Mo or Si were prepared as the sample materials. The hot corrosion behavior of these materials in the exhaust gas-imitative environment was investigated. Finally, the chemical composition of alloy having high corrosion-resistant was showed. The obtained results were as follows:1. The coating of molten Na_2SO_4-NaCI-KCI on the specimen extremely increased the mass gain due to oxidation of pure Ni, Ni-Cr and Ni-Cr-(Si, Mo) alloy.2. The addition of trace amount of HCI into the oxygen atmosphere at high temperature of 1173 K inhibited the oxidation of pure Ni, while that accelerated the oxidation of Ni-Cr alloy.3. The addition of chromium into nickel decreased the mass gain due to oxidation under the coating of molten salt on the specimen in oxygen, oxygen containing HCI and oxygen containing HCI and water vapor. For this case, the formation of a continuous and dense scale consisting of Cr_2O_3 was observed.4. The addition of silicon or molybdenum into Ni-10mass% Cr alloy decreased the mass gain due to oxidation of the alloys under the coating of molten salt on the specimen in oxygen containing HCI atmosphere. For the case, the formation of a dense layer consisting of Cr_2O_3 at the interior side of the scale was observed.Consequently, it was found from the above results that the binary Ni-Cr alloys containing high amount of chromium and the ternary Ni-Cr-(Mo, Si) alloys was suitable as the high corrosion-resistant material for the heat exchange of the exhaust gas in the advanced waste incineration plants.

本研究的目的是开发用于先进垃圾焚烧厂废气热交换的高耐腐蚀材料。由于能够耐受废气环境的金属材料仅限于Ni基合金，因此制备了纯Ni、二元Ni-Cr合金以及含有Mo或Si的三元Ni-Cr合金作为样品材料。研究了这些材料在模拟废气环境中的热腐蚀行为。最后给出了具有高耐蚀性的合金的化学成分。得到的结果如下： 1．在试样上涂覆熔融Na_2SO_4-NaCI-KCI极大地提高了纯Ni、Ni-Cr和Ni-Cr-(Si,Mo)合金氧化导致的质量增加。 2．在1173K高温氧气氛中添加微量HCl抑制了纯Ni的氧化，而加速了Ni-Cr合金的氧化。 3．在镍中添加铬降低了试样在氧、含HCl的氧以及含HCl和水蒸气的氧中熔盐涂层下氧化导致的质量增加。在这种情况下，观察到由Cr_2O_3组成的连续且致密的氧化皮的形成。 4．在Ni-10mass%Cr合金中添加硅或钼降低了在含氧HCI气氛中试样上熔盐涂层下合金氧化导致的质量增益。对于这种情况，观察到在氧化皮内侧形成了由Cr_2O_3组成的致密层。因此，从上述结果可以看出，含铬量高的二元Ni-Cr合金和三元Ni-Cr合金-(Mo、Si)合金适合作为先进垃圾焚烧厂废气热交换的高耐腐蚀材料。