低成本高活性新型活性焦催化脱硫脱硝及再生机制研究

A novel method for preparing an activated coke with new catalytic activities is proposed to solve the problems of the low desulfurization capacity, low denitrication efficiency,large consumption and high cost of desulfurization in the activated coke flue gas desulfurization process. This method includes blending coal with additives of different natural mineral concentrate powders, such as pyrolusite and magnetite. The mechanism of conventional desulfurization/denitrifivation processes by activated coke have been changed from adsorption to catalytic process with the various components of transition metals in these minerals. Therefore, the sulfur capacity and denitrification activity at low temperature of activated coke can be enhanced, and the consumption and costs can be reduced. The morphological changes of different transition metals in the natural minerals during the activation will be simulated and analyzed by the "Gibbs Free Energy of Minimum Theory".The relation between different transition metals and pore structure and surface functional groups of new activated coke will be investigated. The migration and occurrence mechanism of the S element in the new activated coke during the desulfurization and the denitrification performance at low temperature will be clarified. The rule of mineral additives selection and their optimization combination mechanism with coal will be found from mechenism of . The morphological changes of multi-component metals on the prepared activated coke and their influences of pore structure in the heating regeneration process will be studied to find optimal parameters of activated coke preparation and its application in desulfurization/denitrification for reducing the decay rate of the activity and increasing the service life. The results will provide the theoretical support for the popularization and application of novel activated coke for flue gas desulfurization and denitrification.

针对活性焦烟气脱硫脱硝工艺存在的脱硫容量低、脱硝效率低、投资和运行成本高的难题，提出以软锰矿、钒钛磁铁矿等不同天然矿物精矿粉为添加剂，与煤共混制备催化型活性焦的新方法，利用天然矿物精矿富含多种过渡金属，变吸附为催化作用，提高活性焦脱硫容量，增强低温催化脱硝性能，降低活性焦消耗和成本。采用吉布斯自由能最小理论模拟分析天然矿物所含不同过渡金属在活化过程中的形态变化特征，进行不同过渡金属对新型活性焦的孔隙结构和表面官能团的影响机制研究；弄清新型活性焦脱硫过程中S元素迁移及赋存机理，以及低温脱硝性能，研究不同过渡金属组合对脱硫脱硝的影响，形成不同矿物精料与煤共混优化配组机制。通过新型活性焦加热再生过程中多组分金属的形态变化及其对孔隙结构的分析，提出降低活性衰减速度、提高使用寿命的机制，形成新型活性焦制备和脱硫脱硝关键工艺参数，为新型活性焦法烟气脱硫脱硝的推广应用提供技术依据。

针对目前商业活性焦脱硫容量较低导致投资运行成本较高等问题，本项目提出了富含过渡金属的天然矿物精料为添加剂，与煤共混制备低成本新型催化脱硫脱硝活性焦的新方法，系统研究典型金属氧化物和典型天然矿物共混制备新型煤质改性活性焦的制备工艺、脱硫性能及S元素迁移及赋存机理、低温脱硝性能及机理、表面理化特性与脱硫脱硝性能的调控机制、脱硫脱硝工艺参数以及再生解吸机理，并在实验室模拟新型活性焦的脱硫脱硝工业过程。通过成型工艺、活化工艺等研究，分析了金属及天然矿物添加剂对新型活性焦表面理化特性的影响及作用机制，建立了以煤为原料，软锰矿、钛精矿和铜精矿等天然矿物材料为添加剂制备低成本、高活性、稳定性好的新型活性焦吸附/催化剂的制备工艺和参数。研究了不同过渡金属（MnO2、Fe2O3、CuO、Co2O3、Ni2O3、V2O5和TiO2）及其配组改性活性焦的脱硫性能，分析了脱硫过程中活性焦内S元素迁移及赋存机理，弄清了不同过渡金属共混负载活性焦吸附/催化剂的脱硫机理与协同效应；研究了以软锰矿和钛精矿及相应过渡金属为添加剂制备改性活性焦的脱硝性能，分析了复合改性对活性焦脱硝活性的影响及其作用机制，弄清了不同过渡金属及其配组添加剂对活性焦的孔隙结构调控方式与途径，从孔隙结构、官能团、活性组分等方面建立优选不同天然矿物材料添加剂原料与煤炭的共混的配组机制；通过对活性焦脱硫再生条件、天然精矿改性活性焦的循环脱硫再生的影响研究，弄清了新型活性焦吸附/催化材料脱除污染物后的加热再生解吸机理，建立了降低吸附材料的活性衰减速度、提高吸附材料的使用寿命的加热解吸工艺参数。形成新型活性焦制备和脱硫脱硝关键工艺参数，为天然矿物材料和工业废物添加剂与煤共混制备低成本、高活性的脱硫脱硝活性焦吸附/催化剂提供理论依据，有助于活性焦法烟气脱硫脱硝技术在大气污染控制中的大规模推广应用。