報告書番号

W01037

タイトル（和文）

酸素吹きガス化中カロリー燃料用ガスタービン燃焼器の開発 -－第２報 1500℃級ガスタービン燃焼器の設計および高圧燃焼特性－-

タイトル（英文）

Development of Medium-Btu Fueled Gas Turbine Combustor for Oxygen-blown IGCC -2nd report, Design of 1500℃-class Gas Turbine Combustor and Combustion Characteristics at High Pressurized Conditions-

概要 （図表や脚注は「報告書全文」に掲載しております）

乾式ガス精製を採用する酸素吹きガス化中カロリー燃料は発熱量が高く、高カロリー燃料のLNGよりも燃焼温度が高くなり、サーマルＮＯxが高い濃度で排出される。また、燃料中にはフュエルＮＯxの生成源となるアンモニアを含むため、より一層の発電効率の向上およびコスト低減を目的とした乾式ガス精製によるIGCCの実用化にはフュエルＮＯxとサーマルＮＯxの同時低減燃焼技術の開発が必要である。本報告では、これまでの検討で得られた燃焼器設計方針に基づき1500℃級ガスタービン燃焼器を設計、試作し、模擬ガス燃料による燃焼試験により燃焼器性能を確認すると共に、実機ガス燃焼時の燃焼特性を予測した。その結果、ガス化燃料の専焼条件となるガスタービン負荷25％以上の範囲で、フュエルＮＯxを含む全ＮＯx排出濃度(16％Ｏ2換算)は33ppm以下(燃料中ＮＨ3=500ppm、ＣＨ4=0.1％、燃焼器内圧力=1.8MPa)、燃焼効率は99.9％以上を達成した。また、燃焼器出口ガス温度を1600℃まで上昇させても、全ＮＯx排出濃度40ppm以下、燃焼効率99.9％であり、且つ、燃焼器出口ガス温度不均一率P.F.は７％以下、燃焼器壁面温度は材料の耐熱温度(850℃)以下と十分な性能を示した。

概要 （英文）

In order to improve the thermal efficiency of the oxygen-blown IGCC (Integrated Gasification Combined Cycle) for stricter environmental requirements and cost-effective option, it is necessary to adopt the hot/dry gas cleaning system. In this system, the flame temperature of medium-Btu gasified fuel is high enough to produce NOx significantly by fixation of nitrogen in the air. The gasified fuel also contains nitrogenous compounds, in a form such as ammonia (NH3). This ammonia is not removed with the hot/dry gas cleaning system, supplied to the combustor, and easily oxidized to form fuel-NOx in the combustor. It is requisite technology to reduce exhaust NOx produced in the combustor from both fuel- as well as thermal-origin in all kinds of IGCC. In this paper, we demonstrated the low-emission technology by specially designed combustor for oxygen-blown gasified, mediumｭBtu fuels. Major results obtained are as follows:(1) By combustion tests, it was demonstrated that the newly designed combustor with nitrogen direct injection and reducing combustion zone, just like as twoｭstage combustion, resulted in decrease of NOx production from nitrogen fixation to 10ppm (corrected at 16% O2) or less, and in conversion rate of NH3 into NOx upto 60%, in the gas turbine equivalent operational conditions (NH3=500ppm, CH4=0.1%, Pressure=1.8MPa) for IGCC. The CO emission concentration was as low as 20ppm, or the combustion efficiency was kept nearly 100%. Total NOx emission level was 33ppm (corrected at 16% O2).(2) From the view point of higher thermal efficiency of the gas turbine, we tested at elevated firing-temperature up to 1600℃. The combustor showed that the total NOx emissions were less than 40ppm (corrected at 16% O2), CO emissions were also less than 20ppm, and the pattern-factor of outlet gas temperature was less than 7% at expected running conditions. Present tests demonstrated the combustion technology that had sufficient performances for the operational conditions in IGCC that adopted hot/dry gas cleaning system for the medium-Btu fuels.

報告者

キーワード