Basic Research for Reduction of NO_x Emission in Premixed combustion

预混燃烧减少NO_x排放的基础研究

• 批准号: 05650210
• 负责人: YOSHIDA Akira
• 金额: $ 0.96万
• 依托单位: Tokyo Denki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05650210/
• 关键词: Turbulent Premixed Flame; Distributed Reaction Zone; High Intensity Combustion; NO_x; Opposed Jet Burner; Ceramics; Flame Structure; Gas Chromatograph; 対応噴流; ガス分析

The structure of the premixed turbulent flame is divided into two categories, namely, wrinkled laminar flame and distributed reaction zone. Extremely strong turbulence is required to produce the distributed reaction zone, and our knowledge on the emission characteristics of this flame structure is insufficient. In the present study, a ceramic opposed jet burner was designed to assure the adiabaticity. NO_x concentration was measured by two chemiluminescence NO-NO_x analyzers and the stable chemical species were measured by the simultaneous multi-species analyzing system designed using 3 gas chromatographs. The burner has the bell-mouthed exits of propane/air mixture supply tube to eliminate the production of the recirculation zones around the exits. Purely one-dimensional concentration field was established due to the strong mixing perpendicular to the radially stretched vortex vector.In the distributed reaction zone, NO_x formed in the flame zone originates mainly from the prompt-NO mechanism rather than the Zeldovich mechanism and increased with the equivalence ratio. However, in the completely burned gas region, the NO_x formed through the Zeldovich mechanism is predominant and reaches a maximum at the stoichiometric concentration. The amount of NO_x emitted from this burner is extremely small and the emission index is of the order of 1g/kgfuel.By the simultaneous multi-species analyzing system, the concentrations of O_2, N_2, H_2, CO,CO_2, CH_4, C_2H_2, C_2H_4, C_2H_6, C_3H_6, C_3H_6, C_3H_8, i-C_4H_<10>, n-C_4H_<10> are able to be measured simultaneously. The sensitivity of the analyzing system was calibrated against the pure gases. The lower hydrocarbons which are formed by pyrolysis of propane on the unburned gas side of the flame zone are consumed rapidly on the unburned gas side. On the burned gas side, no such lower hydrocarbons were found and the chemical stucture is different from that on the unburned gas side.

预混湍流火焰的结构分为两类，即褶皱层流火焰和分布反应区。这种分布的反应区需要极强的湍流才能产生，而我们对这种火焰结构的发射特性的了解还不够。在本研究中，为保证绝热性，设计了一种陶瓷对置射流燃烧器。用两台化学发光NO-NOx分析仪测定NOx浓度，用3台气相色谱仪设计的多组分同时分析系统测定稳定的化学组份。该燃烧器具有丙烷/空气混合物送风管的钟形出口，以消除出口周围回流区的产生。纯一维浓度场是由于垂直于径向拉伸涡旋矢量的强混合而建立的，在分布反应区内，火焰区形成的NOx主要来源于瞬发NO机制，而不是Zeldovich机制，并且随着当量比的增加而增加。然而，在完全燃烧的气体区，通过Zeldovich机理生成的NOx占主导地位，并在化学计量浓度处达到最大值。该燃烧器排放的NO_x极少，排放指数约为1g/kg燃料，可同时测定O_2、N_2、H_2、CO、CH_4、C_2H_2、C_2H_4、C_2H_6、C_3H_6、C_3H_6、C_3H_8、I-C_4H_1、n-C_4H_1、10&gT；用纯气体对分析系统的灵敏度进行了校准。在火焰区未燃气侧的丙烷热解形成的低碳碳氢化合物在未燃气侧迅速消耗。在燃气侧，没有发现这种低碳氢化合物，化学结构与未燃气侧不同。

项目成果

吉田 亮: "断熱対向噴流予混合火炎のNOx排出特性" 第32回燃焼シンポジウム. 276-278 (1994)

Ryo Yoshida：“绝热对流预混火焰的NOx排放特性”第32届燃烧研讨会276-278（1994）。

Yoshida, A., Uchikura, T., Itoh, J.and Kotani, Y.: "NO_x Emission Characteristics of the Adiabatic Opposed Jet Premixed Flames" The 32nd Jpn. Symp. on Combustion. 276-278 (1994)

Yoshida, A.、Uchikura, T.、Itoh, J. 和 Kotani, Y.：“绝热对向射流预混火焰的 NO_x 排放特性”第 32 届 Jpn.

吉田亮、他3名: "断熱対向噴流予混合火炎のNOx排出特性" 第32回燃焼シンポジウム. 276-278 (1994)

Ryo Yoshida 等 3 人：“绝热对流预混火焰的 NOx 排放特性”第 32 届燃烧研讨会 276-278（1994 年）。