煤和焦炉气联供联产烯烃和电力过程创新和集成优化

The production of olefins highly depends on oil cracking. Coal is the major alternative used to produce olefins through coal gasification techniques. Because of low price of coal, coal-based olefins are more competitive than oil-based olefins from economic point of view. However, coal-based olefins production processes usually suffer from low resource and energy utilization efficiency and high environmental impact. An efficient method is to use coal and coke oven gas together as feedstock, in order for resource complementary. This project is mainly to propose a co-production process of hybrid coal and coke oven gas to olefins and electricity. CH4/CO2 reforming reaction and CO2 recycle as the gasification agent are used to reduce CO2 emission and increase productivity of syngas. Basic techno-economic analysis will be conducted to explore the effect of key factors and their mutual relationship. The process is finally optimized by multi-objective optimisation integrated with life cycle assessment. The best tradeoff is explored by comprehensively considering energy/resource efficiency, economic benefit, and environmental impact.

烯烃生产绝大部分依靠石油裂解，煤炭作为石油替补资源可以通过气化合成气来生产烯烃。由于煤炭价格优势使煤制烯烃比油制烯烃更具经济潜力，但是煤制烯烃从资源/能源利用效率和环境影响角度又存在问题。针对这些问题，研究开发煤联供其它原料实现资源互补，可以大幅度提高资源/能源效率和降低环境污染。本项目提出利用焦炉气的富氢气体与煤气化后合成气进行资源互补，利用CH4/CO2重整和CO2回收气化技术来降低CO2排放和提高合成气的产量，利用联产电力减少自备电厂供能，研究通过技术和经济分析，确定不同关键参数对系统的影响和它们之间的相互制约关系，最后将全生命周期环境分析与多目标优化结合，权衡资源/能源效率，经济效益和环境影响找出集成优化方案，从而实现资源能源的高效利用并降低温室气体排放。

本项目针对我国资源/能源高效清洁利用的重大需求，以提升资源利用效率、减少污染排放和环境影响为目的，建立了煤制烯烃和煤制天然气过程主要技术单元及全流程的物理化学模型，以及“技术-经济-资源-环境”多属性模型。提出了新的二氧化碳捕集工艺流程。通过强化甲醇富液碳解吸过程,与CO2压缩过程中的余热利用耦合集成，二氧化碳捕集率由62% 提升至85%，单位能耗不升反降。将溴化锂吸收式制冷和氨吸收式制冷的串级制冷工艺应用于低温甲醇洗单元，可大幅降低电耗，提高能量效率。利用焦炉气、天然气等富氢气体与煤气化后合成气进行资源互补，集成CH4/CO2重整和CO2回收气化技术，提出了若干个新的富碳资源与富氢资源集成过程。结果表明，新过程的能量效率比传统煤制烯烃过程高了10%，CO2排放率约降低了30%。以上研究成果发表了17篇论文，包括15篇SCI。申请5件发明专利，已授权3件。