【作者】 张学镭；

【导师】 王松岭； 陈海平；

【作者基本信息】 华北电力大学（河北） ， 热能工程， 2007， 博士

【摘要】 焦炉煤气热值较高,是一种优质的气体原料和燃料。我国焦炉煤气资源丰富,但实际利用的数量和水平非常低,造成了严重的资源浪费和环境污染。利用焦炉煤气合成甲醇和燃气-蒸汽联合循环发电具有广泛的应用前景,但由于合成甲醇和发电系统的设计、集成、仿真等问题还没有得到系统的研究,阻碍了对焦炉煤气的利用。基于此,本文研究了焦炉煤气合成甲醇和发电系统关键技术问题,主要内容包括以下几个方面:研究了以焦炉煤气为原料催化部分氧化生产甲醇合成气系统的性能,分析了氧碳比、水碳比、炉前补碳对催化部分氧化反应性能及产物组成的影响,编写了甲醇合成模块的计算程序,设计了鲁奇气相法和浆态床液相法甲醇合成系统的工艺流程,并基于Aspen Plus软件模拟了甲醇合成系统的性能。建立了燃气-蒸汽联合循环关键部件的数学模型:基于基元叶栅法建立了轴流式压气机的变工况模型,提出了基于泵与风机相似定律外推压气机通用特性曲线的方法,并将所得结果进行了验证;基于半经验公式对冷却空气的分配和计算方法进行了研究,建立了PG6541B简单循环燃气轮机性能计算模型,并验证了模型的正确性;提出了燃气轮机变负荷路线图的概念,证明了变负荷路线图是最佳的负荷调节方式;定义了余热锅炉各换热面的传热密度,研究了传热密度在设计工况和变工况下的计算方法,建立了具有整体除氧器的单压余热锅炉性能计算模型。基于所建立的各关键部件的数学模型,对燃烧天然气和焦炉煤气的联合循环性能进行了预测。推导出了燃烧中低热值燃料时燃气轮机系统工况点的调整方案,定量计算了各调整方案对燃气轮机系统热经济性和安全性的影响,并综合热经济性、安全性和可操作性因素,得出增加压气机的压比和关小进口可调导叶的角度分别是燃用焦炉煤气系统和燃用煤基合成气系统的最佳工况点调整方案。提出了焦炉煤气合成甲醇和发电的多联产系统设计方案,分析了各方案的性能,得出采用炉前补碳的气相法甲醇合成与联合循环发电的并联式多联产系统是最佳多联产集成方案。计算了焦炉煤气量发生变化时多联产系统的最佳化电比和变工况性能。分析了电力负荷变化时多联产系统的变工况策略,评估了电负荷的最大调节范围和多联产系统的性能。从技术经济角度评价了焦炉煤气合成甲醇、燃气-蒸汽联合循环发电、并联式多联产三种基准项目的经济性,结果表明三种项目均可盈利。研究了多联产系统产品成本的分摊方法,进行了燃料(原料)价格、产品价格和产品产量的敏感性分析。评价了规模扩大对项目经济性的影响,为不同规模的焦化厂选出了最佳投资项目。更多还原

【Abstract】 Coke oven gas (COG) is high quality raw material and gas fuel with higher heat value. COG is rich in China, but in fact, the utilization amount of COG is very little and the level is very low, which not only wastes the resource, but also pollutes the environment severely. Methanol synthesis and electric power generation by gas turbine combined cycle possess widespread available prospect of using COG, but design, integration, simulation of the system haven’t been studied, which prevents the utilization of COG. So, the key technology of using COG to synthesize methanol and generate electric power is studied in the paper. The main research works of the paper include as follows:The performance of producing methanol synthesis gas with COG as raw material by catalyst-based partial oxidation method is studied in the paper. The influence of oxygen-carbon ratio, water-carbon ratio and supplementary carbon before stove on the performance of catalyst-based partial oxidation and reaction product composition is analyzed in the paper. The calculation program of methanol synthesis module is written, and the process flow of methanol synthesis based on Lurgi gas phase and liquid phase technology are designed and simulated by Aspen Plus software.The mathematic models of key equipments of gas turbine combined cycle are built in the paper. The off-design performance model of axial-flow compressor is built based on blade element method. Another method of extrapolating compressor performance map based on similarity laws is put forward. The results obtained by blade element and extrapolation methods are respectively verified in the paper. The distribution and flow of cooling air is studied based on semi-experience formula, and the performance calculation model of simple cycle of PG6541B gas turbine is built and proven to be true. The conception of varying load route chart is put forward, which is proven to be the optimal load regulation way. Heat transfer density of heat exchanger of heat recovery steam generation is defined, and it’s calculation method on design condition and off-design condition is studied. The performance calculation model of single-pressure heat recovery steam generation with an integral deaerator is built in the paper. The performance of gas turbine combined cycle when firing natural gas and COG is forecasted based on mathematic model of key equipment listed above.Adjustment strategies of gas turbine working condition when burning medium or low heat value fuel were deduced. The influence of each strategy on heat economy and safety operation of gas turbine was calculated quantificationally. Considering heat economy, safety and maneuverability, increasing compressor pressure ratio is optimum strategy for coke oven gas and closing inlet guide vane is optimum strategy for synthesis gas.Design scheme of poly-generation system of using COG to produce methanol and electricity is put forward. The performance of each scheme is analyzed and the result shows that the parallel-type poly-generation system of gas phase methanol synthesis and electric power generation is optimum integration scheme. The optimum methanol-electricity ratio and off-design performance of poly-generation when COG flow is changed are analyzed. Off-design strategy of poly-generation when electrical load is changed, is analyzed also, and the maximum regulating range of electrical load and performance of poly-generation is evaluated in the paper.The economy of COG utilization system, such as methanol synthesis, gas turbine combined cycle, parallel-type poly-generation system, is evaluated from the view of technical economy. The results show that all projects can make profit. Costs apportion method of poly-generation products is studied, and the sensitivity analysis is conducted in order to evaluate the degree of influence of raw material, product price and product output on the economy of each project. Economy of projects with different scales is also evaluated in order to select optimum investment project for coke oven plant with different scale.更多还原