Hydrate-based carbon dioxide capture from simulated integrated gasification combined cycle gas

The equilibrium hydrate formation conditions for CO2/H2 gas mixtures with different CO2 concentrations in 0.29 mol% TBAB aqueous solution are firstly measured.The results illustrate that the equilibrium hydrate formation pressure increases remarkably with the decrease of CO2 concentration in the gas mixture.Based on the phase equilibrium data,a three stages hydrate CO2 separation from integrated gasification combined cycle （IGCC） synthesis gas is investigated.Because the separation efficiency is quite low for the third hydrate separation,a hybrid CO2 separation process of two hydrate stages in conjunction with one chemical absorption process （absorption with MEA） is proposed and studied.The experimental results show H2 concentration in the final residual gas released from the three stages hydrate CO2 separation process was approximately 95.0 mol% while that released from the hybrid CO2 separation process was approximately 99.4 mol%.Thus,the hybrid process is possible to be a promising technology for the industrial application in the future.

Off-design Characteristics of IGCC System Based on Two-stage Coal-slurry Gasification Technology

整体煤气化联合循环（integrated gasification combinedcycle,IGCC）机组在一定情况下处于非设计工况运行。为了研究IGCC系统变工况特性,采用ThermoFlex软件建立基于两段式水煤浆气化技术的200 MW级整体煤气化联合循环系统模型,主要考查燃气轮机负荷、整体空分系数Xas、大气温度、大气压力对系统性能的影响。研究结果表明,降低燃气轮机负荷或者提高大气温度系统效率均呈先升高而后降低的趋势。整体空分系数Xas增加,机组发电效率降低。大气压力对系统效率影响较小。上述条件下采用两段水煤浆气化技术,系统性能可以得到有效改善。研究结果可为采用两段式水煤浆气化技术的IGCC系统的设计、运行提供参考。

DESIGN OF COMBINED CYCLE GENERATION SYSTEM WITH HIGH TEMPERATURE FUEL CELL AND STEAM TURBINE

For environment protection and high efficiency, development of new conceptpower plant has been required in China. The fuel cell is expected to be used in a power plant as acentralized power Station or distributed power plant. It is a chemical power generation device thatconverts the energy of a chemical reaction directly into electrical energy and not limited by Carnotcycle efficiency. The molten carbonate fuel cell (MCFC) power plant has several attractive featuresi.e. high efficiency and lower emission of NO_x and SO_x A combined cycle generation system withMCFC and steam turbine is designed. Its net electrical efficiency LHV is about 55 percent.

Thermodynamic Analysis and Conceptual Design for Partial Coal Gasification Air Preheating Coal-fired Combined Cycle

The partial coal gasification air pre-heating coal-fired combined cycle (PGACC) is a cleaning coal power system, which integrates the coal gasification technology, circulating fluidized bed technology, and combined cycle technology. It has high efficiency and simple construction, and is a new selection of the cleaning coal power systems. A thermodynamic analysis of the PGACC is carried out. The effects of coal gasifying rate, pre-heating air temperature, and coal gas temperature on the performances of the power system are studied. In order to repower the power plant rated 100 MW by using the PGACC, a conceptual design is suggested. The computational results show that the PGACC is feasible for modernizing the old steam power plants and building the new cleaning power plants.

Relations among Main Operating Parameters of Gasifier in IGCC

Gasification unit is one of the key subsystems in the IGCC power system;the operating parameters of gasifier directly affect syngas quality and performance of whole IGCC system. The system model of gasification unit with coal water slurry gasifier was simulated and calculated using THERMOFLEX software, and the relations of oxygen coal ratio (Roc), water coal ratio (Rsc), gasification pressure, gasification temperature and cold gas efficiency were mostly researched. The results show that Roc and Rsc have effect of mutual restriction on gasification temperature, cold gas efficiency and syngas composition. Gasification pressure mainly determines the capacity of the gasifier, little effects on syngas composition.

IGCC机组厂级监控信息系统搭建方案及数据一致性研究

近几年来随着厂级信息监控系统(SIS)研究的不断深入,SIS系统在企业的应用越来越广泛。SIS系统能够对生产过程中产生的数据进行采集与处理,并建立实时、历史数据库,为电厂管理信息系统(MIS)提供过程数据、计算分析结果,实现了设备运行情况在线监视与分析、机组经济性能指标分析、各类报表自动生成等功能,真正做到检修、运行、生产各部门之间的数据共享,满足了电厂对生产过程管控一体化需求,为机组安全、高效运行提供强大支撑。介绍了一种基于IGCC(整体煤气化联合循环)机组厂级信息监控系统搭建方案,并对DCS与SIS的数据一致性进行研究,给类似机组或工程提供参考。

A New Cleaner Power Generation System Based on Self-Sustaining Supercritical Water Gasification of Coal

A new cleaner power generation system(IPGS) is proposed and investigated in this paper. Integrating combined cycle with supercritical water gasification of coal, the thermodynamic energy of the produced syngas is cascade utilized according to its temperature and pressure, both sensible and latent heat of the syngas can be recycled into the system, and thereby the net power efficiency can be about 6.4 percentage points higher than that of the traditional GE gasification based power plant(GEPP). The exergy analysis results show that the exergy efficiency of the proposed system reaches 52.45%, which is 13.94% higher than that of the GEPP, and the improvement in exergy efficiency of the proposed system mainly comes from the exergy destruction decline in the syngas energy recovery process, the condensation process and the syngas purification process. The syngas combustion process is the highest exergy destruction process with a value of 157.84 MW in the proposed system. Further performance improvement of the proposed system lies in the utilization process of syngas. Furthermore, system operation parameters have been examined on the coal mass fraction in the supercritical water gasifier(GF), the gasification temperature, and the gasification pressure. The parametric analysis shows that changes in coal concentration in the GF exert more influence on the exergy efficiency of the system compared with the other two parameters.

回收余热的热电联产IGCC电站研究

整体煤气化联合循环(integrated gasification combined cycle,IGCC)作为洁净煤发电技术,发展为供热机组后,可实现更为清洁的煤基热电联产技术。另一方面,IGCC目前投资较高,若能实现与集中供热结合,供热收益可大幅度改善IGCC的经济性,而以热定电的形式保证了IGCC的年发电小时数,为IGCC的商业化推广提供了一条有力的途径。进行汽轮机乏汽余热回收与烟气余热回收后,IGCC的总体能源利用效率会进一步提高,经济性也将大幅改善。该文研究结果表明:400 MW级的IGCC热电联产系统的热电比为47.2%,总体能源利用效率为57.6%;进行余热回收后,热电比为55.6%,总体能源利用效率为60.8%;在热力站进行吸收式换热改造后,热电比为62.0%,总体能源利用效率为63.4%。

IGCC–甲醇多联产系统节能分析

为评价以气流床粉煤气化为基础的整体煤气化联合循环(IGCC)甲醇多联产系统配置方案,采用Aspen Plus软件对多联产系统进行系统模拟。配置方案中气化工艺分别采用废锅流程和激冷流程,IGCC和甲醇合成组合方式分别采用串联和并联,以相对节能率作为指标对所建立的多联产系统进行评价。结果表明:废锅流程节能效果优于激冷流程。废锅并联组合通往甲醇侧的合成气比例增大时,相对节能率随之增大;废锅串联组合合成甲醇循环气与新鲜气的比例增加时,相对节能率增大。采用分摊算法分别计算了IGCC甲醇废锅并联多联产系统的发电和甲醇合成的煤耗。随着通往甲醇合成侧的合成气量的增加,供电的煤耗显著减少,甲醇合成的煤耗略有减少。

IGCC示范工程煤气化炉的数值模拟

采用Aspen Plus流程模拟软件对某拟建的IGCC示范工程的德士古煤气化炉进行数值模拟,通过考虑碳的不完全转换对计算流程进行了改进,并运用CPD模型预测煤热裂解的产物分布.研究了煤气化炉的重要操作参数(即水煤浆浓度、氧煤比、气化压力和气化温度)对气化结果的影响.在计算区间内,发现高浓度水煤浆浓度范围内,随浓度的增加,煤气的主要成分(H2+CO)的总含量增加.气化温度增大到1400℃左右时,煤气的主要成分随气化温度的进一步增加会趋于一个恒定值.

基于烟煤、褐煤的IGCC系统技术经济性对比

近年来,褐煤提质技术的发展使得褐煤的高效利用成为可能。基于一种先进的褐煤干燥技术—内部废热利用流化床干燥(wirbelschicht-trocknung mit interner abw rmenu-tzung,WTA),采用ASPEN Plus软件及美国电力研究协会(electric power research institute,EPRI)的技术评价准则(technical assessment guide,TAG),分别对烟煤整体煤气化联合循环(integrated gasification combined cycle,IGCC)电站和褐煤IGCC电站进行技术经济性分析。详细介绍了WTA单元及燃气轮机变工况的建模方法。计算结果表明,引入WTA技术后,褐煤IGCC电站的发电效率比采用传统干燥方式时约提高4.6个百分点,整体性能与烟煤IGCC电站相差不大;而褐煤IGCC电站的发电成本比烟煤IGCC电站低24.4%。高效的褐煤干燥技术能显著提高褐煤IGCC电站的效率,而褐煤低廉的价格又对降低发电成本十分有利,褐煤很可能成为比烟煤更适合IGCC的燃料。

基于IGCC的燃烧前CO_2捕集抽蒸汽策略研究

为了降低燃烧前CO2捕集对IGCC蒸汽动力系统出力的不利影响,并保证CO2捕集系统的稳定运行,CO2捕集消耗的蒸汽需要合理的从IGCC系统内部抽取。采用仿真模拟软件,研究了CO2捕集对IGCC系统中燃气轮机、余热锅炉和汽轮机负荷的影响。提出了两种水–气变换反应加湿蒸汽抽汽方案,通过对比这两种加湿蒸汽抽汽方案对汽轮机出力的影响,确定了最优的向CO2捕集系统供汽策略。其中,水-气变换反应加湿蒸汽从气化炉汽包抽取,CO2分离过程消耗的低压加热蒸汽将根据负荷情况由余热锅炉低压蒸汽系统或汽轮机低压缸抽取。

整体煤气化联合循环(IGCC)系统整体综合优化

本文提出ＩＧＣＣ系统两层次和联合循环两大块交叉迭代的整体综合优化的新思路和新方法，对大型ＩＧＣＣ电站系统进行模块化建模和模拟分析，总结和揭示了ＩＧＣＣ系统综合优化的规律，得出了许多有实用参考价值的结论．

氢能经济·CO_2减排·IGCC

从能量利用角度考察了纯粹用氢作燃料的氢能经济的可行性 ,阐述了燃料电池车自身发展的困难和矛盾所在 ,详细地研究了我国二氧化碳的排放源并指出了最切实可行的减排切入点——发电行业 .通过从效率、经济性等角度对发电厂减排 CO2 的各种方案的对比 ,发现 IGCC在CO2 减排方面具有很大的优势 .最后从考察 IGCC的进一步发展方向出发 ,提出了能够真正实现零排放的能源系统和切实可行的减排 CO2

IGCC电站中气化炉控制系统研究

从IGCC电站中的气化炉工作特点分析入手,确定了气化炉控制系统基本结构,并根据气化炉的动态特性,对气化炉控制系统进行了设计。仿真结果表明,气化炉中两个主要环节之间的耦合性较小,可以利用文中的控制系统来完成气化炉主要的控制任务。

与IGCC匹配的燃烧前CO_2捕集系统动态特性分析及控制优化

燃烧前CO_2捕集技术在整体煤气化联合循环发电(IGCC)的应用正处于起步阶段。与传统化工系统里CO_2捕集不同,IGCC发电机组要求能够经常在不同负荷下运行,并能保持较高的系统热效率,因此对其动态特性以及控制方案的研究是十分必要的。针对正在建设的某30MWth的燃烧前CO_2捕集系统,基于DYNSIM软件平台搭建了其MDEA脱硫脱碳工艺流程动态仿真模型,研究了CO_2捕集率对主要调节变量的动态响应特性,并针对其特点提出了优化控制方案。将其与原有方案对比,仿真结果表明,应用该方案不仅可以提升CO_2捕集率的动态响应品质,还降低了能耗。

集成氧离子传输膜的CO_2零排放IGCC系统研究

为进一步降低从整体煤气化联合循环(IGCC)系统中捕集CO2的能耗,研究了一个集成氧离子传输膜(oxygen ion transport membrane,OTM)的富氧燃烧法低能耗捕集CO2的IGCC系统。利用Aspen Plus软件对系统进行了模拟,并对新系统与采用深冷空分的富氧燃烧法捕集CO2的IGCC系统及不回收CO2的IGCC系统进行了比较研究,并分析了OTM原料侧压力、渗透侧压力以及OTM运行温度对新系统性能的影响。研究结果表明:与采用深冷空分的富氧燃烧法捕集CO2的IGCC基准系统相比,集成OTM的新系统效率高出1.88个百分点,比传统不回收CO2的IGCC系统效率下降了6.67个百分点。

IGCC电站燃气轮机启动燃料的替换研究

当整体煤气化联合循环(integratedgasification combined cycle,IGCC)电站低热值合成气燃气轮机的启动燃料为柴油时,启动成本高,污染物难以控制。为了解决该问题,一个较适用的方法是将燃气轮机的启动燃料由柴油替换为天然气。但由于2种燃料的燃烧特性的不同,需要对燃机在两种不同燃料下的动态特性进行深入的研究,从而提出相应的改造和运行策略。基于天津IGCC低热值燃气轮机的结构及实际运行数据,建立燃气轮机热力学计算模型,对比分析了燃气轮机启动过程中,柴油量、天然气量随燃气轮机负荷的变化情况;其次计算了燃烧器燃烧天然气时的火焰稳定速度范围和优化燃烧器当量直径的范围;并对该燃气轮机燃烧室内的燃烧过程进行了数值模拟研究。最后提出了燃烧器的改造方案和运行策略,在尽量小的范围内进行改造来实现对柴油的替代而且保证燃机的稳定、安全和清洁启动。

CO_2捕集对输运床气化炉IGCC系统技术经济性的影响

对整体煤气化联合循环(integrated gasificationcombined cycle,IGCC)电站而言,气化剂(氧气/空气)的选择对系统的流程配置、热力性能及经济性已产生较大的影响。在考虑CO2捕集的情景下,研究不同捕集方法的引入对IGCC带来的影响,具有重要的意义。该文分别构建了输运床氧气及空气气化IGCC系统流程,分析了MDEA及Selexol这2种不同捕集方法的引入对IGCC电站技术经济性的影响。结果表明,无论是氧气还是空气气化电站,都更适合于采用Selexol法捕集CO2。然而Selexol法对空气气化电站供电效率的影响大于氧气气化电站。不捕集CO2时,空气气化电站的供电效率比氧气气化电站高约0.46个百分点,而采用Selexol法捕集系统中90%的CO2后,其供电效率则比氧气气化电站低约0.14个百分点。从经济性角度,空气气化电站具有优势,考虑CO2捕集后,其发电成本仍比氧气气化电站低10$/(MW h)。

燃气轮机变工况对IGCC系统性能的影响

采用成熟的商业软件Thermoflex对拟在国内建设的200MW等级IGCC示范机组进行模拟,并对其进行物质和热平衡的核算。降负荷过程中采用目前联合循环燃气轮机较为常用的IGV(压气机进口可转导叶)调节等T3(透平前温)的调节方式,分析了这种调节方式下燃气轮机负荷率对T3、T4(排气温度)、QGe(燃气轮机排气流量)系统的效率、功率、燃料量和蒸汽侧主要参数的影响,得到了IGCC系统变工况特性及各主要参数变化的一般规律,对系统在变工况时的安全性和经济性进行了必要的分析。结果表明:调节方式直接影响系统的变工况性能,在IGCC系统变工况的过程中为了保证系统的经济性和可靠性,尽量使燃气轮机在IGV调节的范围内调控。