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The use of high-temperature fuel cells as a power technology can improve the efficiency of electricity generation and achieve near-zero emissions of carbon dioxide. This work explores the performance of a 10 kW high-temperature molten carbonate fuel cell. The key materials of a single cell were characterized and analyzed using X-ray diffraction and scanning electron microscopy. The results show that the pore size of the key electrode material is 6.5 µm and the matrix material is α-LiAlO2. Experimentally, the open circuit voltage of the single cell was found to be 1.23 V. The current density was greater than 100 mA/cm2 at an operating voltage of 0.7 V. The 10 kW fuel cell stack comprised 80 single fuel cells with a total area of 2000 cm2 and achieved an open circuit voltage of greater than 85 V. The fuel cell stack power and current density could reach 11.7 kW and 104.5 mA/cm2 at an operating voltage of 56 V. The influence and long-term stable operation of the stack were also analyzed and discussed. The successful operation of a 10 kW high-temperature fuel cell promotes the large-scale use of fuel cells and provides a research basis for future investigations of fuel cell capacity enhancement and distributed generation in China.

In order to solve the problems of the preparation and matching characteristics of key materials in the development of large area and large power molten carbonate fuel cell(MCFC) stack, the assembly and test operation method of 10 kW MCFC stack is proposed. In this paper, the preparation method of matrix and electrode for large area MCFC is proposed. A 10 kW class MCFC power generation system with 120 cells and an effective area of 0.2 m2 for each cell is assembled and operated. In the constant voltage discharge test, the maximum output power is 16.51kw and the current density is greater than 95 mA/cm2. In view of many experiments and analysis, an effective online evaluation method for the baking effect of MCFC electrolyte matrix is obtained, which makes the matrix, electrode and molten salt electrolyte in the molten carbonate fuel cell body form a good match, which has an important guiding significance for improving the assembly and long-term operation of MCFC battery stack. The development and performance test method of the MCFC stack in this paper will provide effective theoretical and experimental guidance for the subsequent development of the larger MCFC power generation system, which is of great significance to promote the commercial demonstration and promotion of MCFC.

As a clean and efficient power generation device, molten carbonate fuel cell(MCFC)can directly convert chemical energy into electrical energy at the operating temperature of 650 degrees, avoiding the heat loss caused by the Carnot cycle, and effectively reducing the emission of CO2 and other pollutants. This paper introduces the background, basic principle, system design and current situation of fused carbonate fuel cell at home and abroad, and explains the technical problems that molten carbonate power generation technology is facing. At the same time, the cost of the molten carbonate power generation system is analyzed, and the present cost and the cost after industrialization are compared and evaluated to provide a reference for the economy of the molten carbonate fuel cell power generation system.

The test of 10 kW high-temperature molten carbonate fuel cell of the carbon dioxide near-zero emission technology project was carried out. The key materials of the molten carbonate fuel cell single cell were characterized and analyzed by XRD and SEM. The results show that the pore size of key electrode material was 6.5 µm and the matrix material is α-LiAlO2.The open circuit voltage of the single cell is 1.23V in experiment. The current density is greater than 100 mA / cm2 when the operating voltage is 0.7V. The 10 kW fuel cell stack was constitutive of 80 pieces single fuel cells with area of 2000 cm2. The open circuit voltage of the stack reaches above 85V. The fuel cell stack power and current density can reach 11.7 kW and 104.5 mA/cm2 when the operating voltage is 56V. The influence and long-term stable operation of the stack were also analyzed and discussed.

Global methane emission from coal mines were estimated to be approximately 584 MMTCO2 E in 2010, which is a huge waste of energy resources and is an important source of greenhouse gas (GHG) emission. Coal mine methane (CMM) whose methane content is 30∼60% with the rest of air is difficult to use directly. A novel process for CMM utilization is developed in this work. CMM is used as the feedstock for urea synthesis. This process does not require separation or further purification of CMM, but converts the methane into hydrogen through the oxygen in it and by adding steam. The reformate can be further processed into a mixture of hydrogen and nitrogen with a molar ratio of H2:N2 = 3:1, which can then be used for urea synthesis. This process has been analyzed by Aspen Plus. It is found that the optimal CMM composition for urea production is 42% of methane in the air system, with water added at an H2O/CH4 ratio of 3.26. Reforming catalyst has been developed and tested in a simulated industrial reactor, with CMM simulated by mixing civil use grade methane and air. The reformate composition was analyzed by gas chromatography (GC) and the results match the simulation very well. A 10-day test showed high stability of the catalyst. In addition, the reforming catalyst after 10 days of operation was characterized using XRD and Laser Raman. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd.

The fuel cell-based distributed energy supply system has low pollution emission, low noise, and modular advantages. This paper aims at a 100 kW-class MCFC cogeneration system using natural gas as fuel. The MCFC unit model was developed based on the lumped parameter method. A parallel system and a series system model were built. The effect of single cell voltage and fuel cell stack arrangement on system efficiency, operating temperature, catalytic burner operating parameters, etc. are analyzed. As a result, the series system in which two fuel cell stacks arranged in series can improve the stack efficiency and the system power generation efficiency. Compared to a parallel system in which two fuel cell stacks arranged in parallel, the stack efficiency and the system power generation efficiency of the series system are 6 to 8 percentage points higher than that of the parallel system. For the series system, the air needed to be graded to maintain the operating temperature of the second-stage stack, the air ratio was about 2.75; the power ratio of the two stacks was about 8.0. Compared with the catalytic burner in the parallel system, the inlet burner temperature in the series system increased by about 50 °C, and the inlet hydrogen mole fraction in the series system was reduced by 1 percentage point. The heat balance design of the catalytic burner in the series system was required.

Coal-fired gasifiers are the key technology for clean power generation and coal chemical process. This paper presents a 2-stage entrained flow dry powder gasifier in which coal is entrained into the lower chamber burner with oxygen and steam to raise the temperature of the crude gas up to 1700 °C. The lower chamber is linked to the upper gasification chamber through a middle throat, where additional coal and steam is fed to cool down the slag to less than 900 °C for deslagging from the lower chamber bottom. Various coals have been characterized and gasified with this 2-stage entrained flow dry powder gasifier and comparisons made with single stage gasifiers. The results show that the 2-stage gasifier is suitable for a broad range of coal varieties and gives carbon conversion up to 98.9% with cold syngas efficiency of 83.2% at a pressure of 3.0 MPa, while the oxygen and coal consumption are lower than with the single stage gasifier.

In this article the prospect of emerging co-production and polygeneration schemes based on pre-combustion decarbonisation and options for geological storage of the CO2 are discussed in a European and Chinese setting. Reference is made to European and Chinese undertakings – especially the COACH project1 that is being conducted under the auspices of the European Commission. COACH is based on principles lined up by the EU-based DYNAMIS2 project with reference to options for decarbonising fossil fuels within a more sustainable framework.

A key component in the molten carbonate fuel cell (MCFC) is electrolyte matrix, which provides both ionic conduction and gas sealing. The aim of this work is to investigate the effects of selected operating conditions on the performance of the matrix preparation. Slurries were prepared to produce matrices by the technique of tape casting. The characteristics of the slurries and matrices were examined by laser particle size analyzer, scanning electron microscopy, and BET surface area analyzer. The testing results revealed that a slurry composition with 40 wt.% lithium aluminate was the optimal formulation to produce a good matrix with a pore size distribution of 0.1–0.4 μm and porosity of 50 vol.%. Coarse and fine LiAlO2particles were added in the matrix slurry to enhance the mechanical strength. Several green sheets were heated and pressed to enhance the bulk density to get a dense matrix of MCFC. Finally, a single MCFC was assembled and tested. The testing results showed the matrix with 40% solid loading gave the maximum discharge current of 20 A at 0.56 V.

Coal-fired power plants are the largest sources of mercury in China as well as United States, accounting for nearly 50% of industrial mercury releases. USA consumed much more coal than China before 1987, while no Hg control measures had been taken during this period. There has been lots of background Hg emitted into air system, including those from mining, oil & gas extraction, coal combustion, volcanoes and geothermal et.al. However the coal combustion has been considered as the dominant sources. Since 2005, quite a few coal power plants started adopting mercury control measures based on the powder Active Carbon Injection (ACI) technology in USA, metallic Hg emission to air environment has been thus significantly reduced, but leading to Hg content in fly ash is up to 10 ppm, potentially a Hg pollution source if not disposed properly. Although short terms studies have showed little leachate of Hg occurred from the fly dust, there is a potential that the landfilled or dumped dust may be a possible source for the Hg leachate to contaminate underground water in long term, as Hg is mainly trapped as Hg2+ or other forms, which are either soluble or minor soluble in water and could go to water environment. Based on this analysis, a more safe and reliable Hg removal technology has been developed and tested.