Reduction of unburnt gas and nitrous oxide emissions from fluidized bed combustor by use of capacitance effect of porous bed materials

利用多孔床材料的电容效应减少流化床燃烧器未燃气体和一氧化二氮的排放

• 批准号: 11218204
• 负责人: SHIMIZU Tadaaki
• 金额: $ 13.5万
• 依托单位: Niigata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11218204/
• 关键词: coal; fluidized bed combustion; nitrous oxide; nitrogen oxides; porous particle; capacitance effect; thermal decomposition; dioxins; 炭化水素

The objective of this work is reduction of N_20 emission, which is known to be a greenhouse effect gas, and emissions of unburnt hydrocarbons including dioxins from fluidized bed coal combustors. In this work we proposed to employ porous bed material instead of conventional non-porous sand. The present research project clarified that porous bed materials had so-called "capacitance effect", I. e., hydrocarbon capture at high temperatures and retention of carbon within pores, and catalytic activity to decompose N_2O. The present work investigated the effect of such porous bed materials on emissions of hydrocarbons, unburnt carbon, N_2O and Nox during fluidized bed combustion using a bench-scale reactor. For comparison, inert and non-porous sand was also employed as bed material. The porous bed material was found to be effective for reduction of emissions of unbunrt fractions including dioxins.The present work employed two kinds of porous alumina bed materials and compared the results with those for the sand bed. Both alumina particles reduced N_2O emission in comparison to the sand bed. This was explained by the catalytic activity of these bed materials to decompose N_2O. However, the effect of bed material on Nox emission was different between the porous bed materials ; One of the porous alumina bed materials reduced Nox emission whereas the other increased. A kinetic study was conducted for Nox formation from a volatile nitrogen compound (ammonia). The fate of nitrogen compounds in the fluidized bed is discussed.Also the reduction of the unburnt hydrocarbon/carbon emissions by porous bed materials was carried out using a bench-scale reactor. In addition, a kinetic study on hydrocarbon capture and combustion of captured carbon was conducted using a fixed bed reactor. The effect of bed material type and temperature on hydrocarbon capture and carbon burn-up was evaluated.

这项工作的目标是减少已知的温室效应气体N_20的排放和包括二恶英在内的未燃烧碳氢化合物的排放。在这项工作中，我们提出用多孔床材料代替传统的无孔砂。本研究项目阐明了多孔床材料具有所谓的“电容效应”，即在高温下捕获碳氢化合物，并将碳保留在孔内，以及催化分解N_2O的活性。本工作利用小型反应器研究了多孔床材料对沸腾床燃烧过程中碳氢化合物、未燃碳、N2O和NOx排放的影响。为了进行比较，还使用了惰性砂和无孔砂作为床料。采用两种多孔氧化铝床层材料，并与砂床的实验结果进行了比较。与砂床相比，两种氧化铝颗粒都减少了N2O的排放。这是由于这些床料具有催化分解N_2O的活性。然而，床料对NOx排放的影响不同于多孔床料，一种多孔氧化铝床料降低了NOx排放，另一种增加了NOx排放。对挥发性氮化合物(氨)生成氮氧化物的动力学进行了研究。讨论了氮化物在床层中的去向，并利用小型反应器进行了多孔床材料对未燃碳氢化合物/碳排放的降低。此外，还利用固定床反应器对碳氢化合物的捕获和燃烧进行了动力学研究。考察了床料类型和温度对碳氢化合物捕集和燃耗的影响。

项目成果

T.Shimizu, M.Peglow, K.Yamagiwa, M.Tanaka, S.Sakuno, N.Misawa, N.Suzuki, H.Ueda, H.Sasatsu, H.Gotou: "A simplified model of SO_2 capture by limestone in a 71 MWe pressurized fluidized bed combustor"Chemical Engineering Science. 57巻,19号. 4117-4128 (2002)

T.Shimizu、M.Peglow、K.Yamagiwa、M.Tanaka、S.Sakuno、N.Misawa、N.Suzuki、H.Ueda、H.Sasatsu、H.Gotou：“石灰石捕获 SO_2 的简化模型71 MWe加压流化床燃烧室《化学工程科学》.第57卷第19期.4117-4128(2002)

H.J.Franke, T.Shuinizu, Y.Takano, S.Hori, M.Strziga, M.Inagaki, M.Tanaka: "Reduction of devolatilization rate of fuel during bubbling fluiclized bed combustion by use of porous bed material"Chemical Engineering and Technology. Vol.24, No.7. 725-733 (2001)

H.J.Franke、T.Shuinizu、Y.Takano、S.Hori、M.Strziga、M.Inagaki、M.Tanaka：“利用多孔床材料降低鼓泡流化床燃烧过程中燃料的脱挥发分率”化学工程与技术

H.-Jurgen Franke,Tadaaki Shimizu, 他5名: "Proceeings of 3rd European Conference on Fluidization(Toulouse,France,29-31 May 2000)"Societe Francaise de Genie des Procedes. 8 (2000)

H.-Jurgen Franke、Tadaaki Shimizu 和其他 5 人：“第三届欧洲流态化会议论文集（法国图卢兹，2000 年 5 月 29-31 日）”Societe Francaise de Genie des Procedes 8 (2000)。

清水忠明, H.-J.Fralike, 堀彩統子, 高野康夫, 山際和明, 田中真人: "多孔質粒子流動媒体による気泡流動層焼却炉からのダイオキシン類の排出低減"日本エネルギー学会誌. 80巻,11号. 1060-1063 (2001)

Tadaaki Shimizu、H.-J.Fralike、Noriko Hori、Yasuo Takano、Kazuaki Yamagiwa、Masato Tanaka：“使用多孔颗粒流化介质减少鼓泡流化床焚烧炉的二恶英排放”，日本能源研究所杂志第 80 卷， 11. 1060-1063（2001）

Tadaaki Shimizu, Mirko Peglow, Kazuaki Yamagiwa, Masato Tanaka: "A model of SO_2 removal by single limestone particle under pressurized fluidized bed combustion conditions with solid attrition"Nihon-Energy-Gakkai-Shi (J. Jpn. Inst Energy). 80, No. 3. 206-

Tadaaki Shimizu、Mirko Peglow、Kazuaki Yamagiwa、Masato Tanaka：“在加压流化床燃烧条件下采用固体磨损的单个石灰石颗粒去除 SO_2 的模型”Nihon-Energy-Gakkai-Shi (J. Jpn. Inst Energy)。