生物质再燃过程中碱(土)金属和氯迁移及其对氮汞协同控制机理研究

项目名称： 生物质再燃过程中碱(土)金属和氯迁移及其对氮汞协同控制机理研究

项目编号： No.51476079

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 能源与动力工程

项目作者： 卢平

作者单位： 南京师范大学

项目金额： 83万元

中文摘要： 燃煤烟气NOx和汞多污染物联合控制近年来得到了国内外高度关注。采用吸附剂喷射和烟气调质相结合是极具发展前景的汞污染控制技术，但由于吸附剂成本和烟气调制等问题限制了该技术应用。本项目基于生物质再燃脱硝脱汞的新方法，结合生物质含有较高碱(土)金属(AAEMs, 如K, Na, Ca和Mg)和氯的特点，通过生物质再燃在烟气和飞灰中形成合适含量的AAEMs和氯，强化NOx还原和单质汞催化氧化，使其在大气污染控制设备(APCDs)中高效脱除。本项目利用固定床和携带流反应装置，研究生物质种类、反应温度、反应气氛、停留时间、飞灰与添加剂等对生物质热解和再燃条件下AAEMs和氯的迁移转化规律，考察AAEMs和氯参与条件下烟气中NOx还原与单质汞形态转化的规律，探索再燃条件下AAEMs和氯迁移对烟气中NOx和Hg关联控制机理，建立以AAEMs、氯、氮和汞迁移和关联行为为核心的机理模型，获得生物质再燃多污染物联合控制的关键影响因素，以期通过对生物质的筛选、改性以及工艺优化，最大限度地发挥生物质再燃的功效。

中文关键词： 生物质再燃；碱(土)金属；氮氧化物；汞；协同脱除

英文摘要： The technologies for controlling multi-pollutants, such as NOx and mercury, etc. in coal-fired flue gas has been gained high attention at home and abroad in recent years. The combination of sorbent injection and flue gas conditioning bas been considered as a promising mercury control technology, however, this techonology is not applied widely due to the limitation of sorbent cost and flue gas conditioning technology. On the basis of the characterics of low sulfur, low nitrogen and higher contents of AAEMs (Alkali and alkali earth metals, mainly K, Na, Ca and Mg) and chlorine bound in biomass, the new method of simultaneous removal of NOx and mercury through biomass reburning was put forward to form appropriate concentrations of AAEMs and chlorine in the flue gas and flyash, in order to promote the NO redution and the catalytic oxidation of elemental mercury, and finally to achieve simultaneous control of NOx and mecury in conventional air pollution control devices (APCDs). In this project, the migration of AAEMs and chlorine will be focused on, and the characteristics of migration and transformation of AAEMs and chloride bound in biomass will be carried out in a fixed-bed and an entrained-flow ractors, the effect of biomass species, reaction temperature, stoichiometric ratio, residence time, flyash and additives etc. on migration and transformation of AAEMs and chlorine during biomass reburning will be studied, and the control mechanism of NOx and Hg will be analyzed. The mechanism models based on the migration and interaction effects of AAEMs, chlorine, nitrogen and mercury will be put forward. The key influencing factors of multi-pollutants control during biomass reburning will be obtained. A mothod of selection and modification of biomass fuels and optimization of rebrning process will also be put forward. It will built a foundation to realize the maximum effect of the removal of NOx and mercury during biomass reburning.

英文关键词： biomass reburning;alkali and alkali earth metals (AAEMs);NOx;Mercury;simultaneous removal