SGER: Analysis of Exterally-Sustained MMHD Processes for Enhanced Electrical Power Generation Efficiency Using Gas from Reformed Coal

0120617英里本研究计划将探索电子束持续磁流体发电的潜力，以提高先进地面燃煤电厂的电力效率。在传统的MHD中，所需的高温(即使是播种)会导致大量的氮氧化物产生。电子束支撑的MHD能够在相对较低的温度下工作，而不需要向流动中添加种子材料。较低的温度允许探索各种新的、可能是高效率的、低污染的方法，其中最理想的是利用高火焰温度来驱动高速、低温超音速流动，通过超音速膨胀迅速冷却氮氧化物的形成。电子束持续MHD提供的导电性的主动控制也为MHD工艺打开了先进控制方法的大门，特别是抑制寄生电流路径并允许在动态模式下运行，从而可能允许改进性能。电子束沿着磁力线进入MHD通道，产生的二次电子维持导电性。为了抑制电子损失率，沟道必须在低压下工作。对于地面设施，这意味着气流将需要超音速。由于煤渣沿墙壁的存在将导致电子束传输到MHD通道的困难，研究的主要重点将是研究电子束MHD概念与将煤转化为氢和二氧化碳的新的膜技术气化过程的耦合。MHD有可能在高于涡轮进口温度限制的温度下通过燃烧更有效地电转化氢气。这项研究探索了电子束持续MHD用于高效转化的可能性，通过在超音速喷管内燃烧独立地控制燃烧温度，通过动力学速率差形成氮氧化物，并优化电导率分布。模拟表明，如果电子损失率最小，则电子束的成本可以相对较小。

0120617MilesThis research program will explore the potential of electron beam sustained MHD power generation for enhancing the electrical efficiency of advanced ground based coal fired power plants. In conventional MHD, the high temperatures that are required (even with seeding) lead to significant oxides of nitrogen production. The electron beam sustained MHD has the capability of operating at relatively cool temperatures, without the need for seed material to be added to the flow. The lower temperature allows of a variety of new, possibly high efficiency, low polluting approaches to be explored, the most desirable of which would be the utilization of the high flame temperature to drive a high velocity, low temperature supersonic flow with rapid quenching of the formation of oxides of nitrogen through a supersonic expansion. The active control of the conductivity that electron beam sustained MHD affords also opens the door to advanced methods of control for MHD processes, particularly to suppress parasitic current paths and permit operation in dynamic modes that might allow for improved performance. The electron beams enter the MHD channel along magnetic field lines, and the conductivity is sustained by the secondary electrons that are produced. To suppress the electron loss rate, the channel must be operated at low pressure. For ground based facilities, this means the flow will need to be supersonic. Since the presence of coal slag along the walls will cause difficulty with electron beam transmission into the MHD channel, the main focus of the research will be to examine the coupling of the electron beam MHD concept together with new membrane technology gasification processes that convert coal to hydrogen and CO2. MHD has the potential for more efficient electrical conversion of hydrogen through combustion at a temperature higher than is possible with turbine inlet temperature limits. This research explores the possibility of e-beam sustained MHD for high efficiency conversion by independentlycontrolling the combustion temperature through combustion in a supersonic nozzle, the formation of oxides of nitrogen through kinetic rate differentials, and the optimization of the conductivity profiles. Modeling indicates that the cost of the electron beams can be relatively small if the electron loss rate is minimized.