铁基载氧体表界面液烃燃料反应特性与污染物减排机理

The chemical looping principle is put forward to combine with the traditional method of oil furnace to produce the carbon black (CB) in this project to overcome the shortcoming of heavy pollution and high energy consumption and to innovate the CB production craft. However, the knowledge of liquid hydrocarbon fuel pyrolysized in the lower temperature and the NO/SO2 emission reduction is very limited with the application of Fe-based oxygen carrier. Based on the Chemical Thermodynamic and Molecular dynamics calculations, the experiments and numerical simulation works would be carried out for the flow reaction in the fuel reactor of monobed or serious fluidized bed systems and the reaction kinetics model of CB production from liquid hydrocarbon fuel based chemical looping pyrolysis would be built. It is the foundation to control deeply the CB aggregation configuration development. The complex pyrolysis reaction of liquid - solid and gas - solid phases would be in focus studied for the mechanisms over the surface and interface of Fe-based oxygen carrier (OC). The principle of surface reaction activity varied with the reaction cycles would be investigated in detail, and the hydrogen/nitrogen/sulphur elements released from the hydrocarbon fuel may react competitively in the multiphase flow, the growth characters of CB aggregation need to be explored deeply. Based on these researches, the complex reaction in the multi-phases flow in the fluidized fuel reactor would be clear, and the emission reduction effect would be proved. The technique route of CB production on chemical looping pyrolysis (CLP) from liquid hydrocarbon fuel, with the advantage of low energy consumption cooperated with the emission reduction, is the development of chemical looping process by the combination of relative subject knowledge, is of the important academic significance and engineering value.

常规油炉法炭黑生产具有高污染高耗能缺点，本申请提出利用清洁高效的化学链过程革新现有工艺以实现炭黑生产的节能减排。然而，对于铁基载氧体作用下液烃燃料较低温热裂解并深度脱氢的反应特征及NO/SO2减排机理的认识仍十分有限，本申请拟借助化学热力学和分子动力学理论，通过对单床/串行流化床系统燃料反应器中流动反应开展实验和数值模拟，建立基于化学链热解的液烃燃料制取炭黑反应动力学模型，为调控炭黑聚集体结构奠定基础。重点研究铁基载氧体表界面的液烃燃料热裂解涉及的液-固、气-固反应机理以及多循环载氧体反应活性演变规律；试图解释燃料挥发物氢氮硫的气相组分竞争反应机制以及炭黑聚集体生长特性；完成燃料反应器多相流体系中复杂反应的透彻分析，同时理解对污染组分的减排机理。本项目通过相关学科知识的交叉运用，拓展了化学链过程的应用，为实现液烃燃料的低温热裂解和污染物减排提供理论依据，具有重要的学术意义和工程价值。

目前碳黑生产广泛应用的油炉法工艺，能耗高、污染严重、生产成本极高。利用流化床内高密度传热传质、清洁燃烧的本质，本项目提出并研究了粒度较为均匀的铁基载氧体颗粒在流化床内化学链热解煤焦油的新工艺，除了制得一定热值的燃气，碳黑的收率67-70%也接近油炉法。该化学链工艺大幅度降低了反应温度，则降低了碳黑生产能耗和污染，其中铁基载氧体的载氧和催化性能、粒径均匀化利于碳黑与载氧体颗粒的分离和碳黑品质、钙添加对提高复合载氧体循环周期以及污染物减排的作用和机理，成为本项目的主要研究内容。获得的主要研究成果：（1）通过单床/串行流化床实验系统中流动反应的实验研究及数值模拟，确定了化学链热解液烃燃料制取碳黑的反应动力学模型，为调控碳黑聚集体结构和碳黑微团链强度奠定基础。（2）通过研究煤焦油热裂解过程铁基载氧体表界面得氧-释氧行为及其催化机理，确定了铁基载氧体表界面碳氢燃料的反应特性及载氧体抗积碳性能；（3）为保证碳黑品质，载氧体颗粒的粒度均匀性及活性起到了关键作用，而铁基载氧体机械强度较弱（导致颗粒度演变）也是其应用的最大制约，本研究通过钙添加制备的复合载氧体颗粒，延长了其循环性能，提高了机械强度并降低了CO2/NOx/SO2的排放。（4）对于煤气化粗气中煤焦油含量较高的气体净化，无需气体急冷，按照本项目的化学链路线进行煤焦油热解，提高煤气化气的品质，完成高温状态的煤焦油净化，这是竞争性气体反应的实际应用。本项目尝试了铁基载氧体的结构和组分优化，对其表面与碳氢燃料的气固反应和固固反应机理进行了深入理解，并在煤焦油制碳黑工艺上尝试实际应用。通过相关学科知识的交叉运用，拓展了化学链技术的应用。