Development and integration of underground coal gasification (UCG) for improving the environmental impact of advanced power plants

2010 ◽  
pp. 332-363
Author(s):  
M. Green
Keyword(s):  
Environmental Impact ◽  
Power Plants ◽  
Coal Gasification ◽  
Underground Coal Gasification

The Exergy Underground Coal Gasification Technology as a Source of Superior Fuel for Power Generation

2006 ◽  
Author(s):  
Michael S. Blinderman
Keyword(s):  
Power Generation ◽  
Power Plants ◽  
Coal Gasification ◽  
Underground Coal Gasification ◽  
Fuel Gas ◽  
Gasification Process ◽  
Product Gas ◽  
Production Wells ◽  
Industrial Projects ◽  
Fossil Fuel Power Plants

Underground Coal Gasification (UCG) is a gasification process carried on in non-mined coal seams using injection and production wells drilled from the surface, converting coal in situ into a product gas usable for chemical processes and power generation. The UCG process developed, refined and practiced by Ergo Exergy Technologies is called the Exergy UCG Technology or εUCG® Technology. The εUCG technology is being applied in numerous power generation and chemical projects worldwide. These include power projects in South Africa (1,200 MWe), India (750 MWe), Pakistan, and Canada, as well as chemical projects in Australia and Canada. A number of εUCG based industrial projects are now at a feasibility stage in New Zealand, USA, and Europe. An example of εUCG application is the Chinchilla Project in Australia where the technology demonstrated continuous, consistent production of commercial quantities of quality fuel gas for over 30 months. The project is currently targeting a 24,000 barrel per day synthetic diesel plant based on εUCG syngas supply. The εUCG technology has demonstrated exceptional environmental performance. The εUCG methods and techniques of environmental management are an effective tool to ensure environmental protection during an industrial application. A εUCG-IGCC power plant will generate electricity at a much lower cost than existing or proposed fossil fuel power plants. CO2 emissions of the plant can be reduced to a level 55% less than those of a supercritical coal-fired plant and 25% less than the emissions of NG CC.

scholarly journals Combined Cycles Permit the Most Environmentally Benign Conversion of Fossil Fuels to Electricity

1990 ◽  
Author(s):  
Guenther Haupt ◽  
John S. Joyce ◽  
Konrad Kuenstle
Keyword(s):  
Environmental Impact ◽  
Power Plants ◽  
Fossil Fuels ◽  
Coal Gasification ◽  
High Efficiency ◽  
Waste Heat ◽  
Primary Energy ◽  
Combined Cycle ◽  
Point Of View ◽  
Steam Boiler

The environmental impact of unfired combined-cycle blocks of the GUD® type is compared with that of equivalent reheat steam boiler/turbine units. The outstandingly high efficiency of GUD blocks not only conserves primary-energy resources, but also commensurately reduces undesirable emissions and unavoidable heat rejection to the surroundings. In addition to conventional gas or oil-fired GUD blocks, integrated coal-gasification combined-cycle (ICG-GUD) blocks are investigated from an ecological point of view so as to cover the whole range of available fossil fuels. For each fuel and corresponding type of GUD power plant the most appropriate conventional steam-generating unit of most modern design is selected for comparison purposes. In each case the relative environmental impact is stated in the form of quantified emissions, effluents and waste heat, as well as of useful byproducts and disposable solid wastes. GUD blocks possess the advantage that they allow primary measures to be taken to minimize the production of NOx and SOx, whereas both have to be removed from the flue gases of conventional steam stations by less effective and desirable, albeit more expensive secondary techniques, e.g. flue-gas desulfurization and DENOX systems. In particular, the comparison of CO2 release reveals a significantly lower contribution by GUD blocks to the greenhouse effect than by other fossil-fired power plants.

scholarly journals Is the Złoczew lignite deposit geologically suitable for the first underground gasification installation in Poland?

Geologos ◽  
2020 ◽  
Vol 26 (2) ◽  
pp. 113-125
Author(s):  
Paweł Urbański ◽  
Marek Widera
Keyword(s):  
Power Plants ◽  
Coal Gasification ◽  
Alternative Methods ◽  
Future Application ◽  
Opencast Mining ◽  
Underground Coal Gasification ◽  
Negative Effects ◽  
Environmental Conflicts ◽  
Underground Gasification ◽  
Geological Conditions

AbstractThe present study focuses on alternative methods of exploiting lignite in comparison to conventional opencast mining and combustion in power plants for the generation of electricity. In Poland, opencast lignite pits cover large areas, creating social and environmental conflicts. In order to stabilise the production level of electricity and reduce the negative effects of opencast mining, alternative ways of exploiting lignite are suggested, one of these being underground gasification in situ. The Złoczew lignite deposit, which will most likely be exploited in the near future, provides an opportunity to discuss the unconventional method of underground coal gasification (UCG). On the basis of technological and geological criteria that have been established to determine the suitability of Polish lignite for underground gasification, resources to be used this way have been estimated. Through gasification, over 15 million tonnes of lignite can be utilised, which is about 2.5 per cent of resources of the Złoczew deposit intended for opencast mining. With this in mind, we suggest to take action by starting a pilot installation, to be followed by a commercial one for underground gasification after completion of superficial mining. Naturally, any future application of this method will be preceded by assessment of geological conditions at the Złoczew opencast pit.

Evaluation of Applying Low Calorific Fuel as Reburn Fuel in an Opposed Wall Fired Boiler

2009 ◽  
Vol 1 (3) ◽  
Author(s):  
Guang Xu ◽  
Wei Zhou ◽  
Larry W. Swanson ◽  
David K. Moyeda ◽  
Quang Nguyen
Keyword(s):  
Natural Gas ◽  
Thermal Performance ◽  
Power Plants ◽  
Alternative Fuels ◽  
Coal Gasification ◽  
Renewable Energy Sources ◽  
Heat Transfer Analysis ◽  
Injection System ◽  
Chemical Compositions ◽  
Underground Coal Gasification

The alternative fuels, such as biomass, municipal wastes, and underground coal gasification gas, become attractive to the power plants as renewable energy sources or economical fuels. However, the alternative fuels usually have much lower heating value and different chemical compositions from those of coal and natural gas. Firing these alternative fuels in the boilers that are originally designed for coal firing or natural gas firing may cause unexpected boiler operating issues and/or thermal performance degradation. A careful evaluation study is often required prior to implementation. This paper presents the results of a study that evaluated the feasibility of using an underground coal gasification gas as a reburn fuel. The evaluation was done on Eskom’s Majuba Unit 5, a 710 MWe opposed wall-fired boiler, located in South Africa. The study utilized heat transfer analysis and computational fluid dynamics models to (1) evaluate the impacts of firing low calorific fuel on boiler efficiency and the boiler auxiliary system performance, (2) develop a conceptual gas reburn injection system, and (3) evaluate the impacts of gas reburn on the boiler thermal performance and boiler NOx emissions. The results indicate that the underground coal gasification gas can be an effective reburn fuel for the Majuba boiler with upgrades on the auxiliary systems.

Underground Coal Gasification for Power Generation: High Efficiency and CO2-Emissions

2004 ◽  
Author(s):  
Michael S. Blinderman ◽  
Bernard Anderson
Keyword(s):  
Co2 Emissions ◽  
Gas Turbines ◽  
Power Plants ◽  
Coal Gasification ◽  
High Efficiency ◽  
Gas Production ◽  
Western World ◽  
Underground Coal Gasification ◽  
Thick Coal Seam ◽  
Wide Range

Underground Coal Gasification (UCG) is a gasification process carried out in non-mined coal seams using injection and production wells drilled from the surface, enabling the coal to be converted into product gas. The UCG process practiced by Ergo Exergy is called Exergy UCG or εUCG. εUCG was applied in the Chinchilla UCG-IGCC Project in Australia. The IGCC project in Chinchilla, Australia has been under development since July 1999. The project involves construction of the underground gasifier and demonstration of UCG technology, and installation of the power island. Since December 1999 the plant has been making gas continuously, and its maximum capacity is 80,000 Nm3/h. Approximately 32,000 tonnes of coal have been gasified, and 100% availability of gas production has been demonstrated over 30 months of operation. The UCG operation in Chinchilla is the largest and the longest to date in the Western world. The εUCG facility at Chinchilla has used air injection, and produced a low BTU gas of about 5.0 MJ/m3 at a pressure of 10 barg (145 psig) and temperature of 300° C (570° F). It included 9 process wells that have been producing gas manufactured from a 10 m thick coal seam at the depth of about 140 m. The process displayed high efficiency and consistency in providing gas of stable quality and quantity. The results of operations in Chinchilla to date have demonstrated that εUCG can consistently provide gas of stable quantity and quality for IGCC power projects at very low cost enabling the UCG-IGCC plant to compete with coal-fired power stations. This has been done in full compliance with rigorous environmental regulations. A wide range of gas turbines can be used for UCG-IGCC applications. The turbines using UCG gas will demonstrate an increase in output by up to 25% compared to natural gas. The power block efficiency reaches 55%, while the overall efficiency of the UCG-IGCC process can reach 43%. A UCG-IGCC power plant will generate electricity at a much lower cost than existing or proposed fossil fuel power plants. CO2 emissions of the plant can be reduced to a level 55% less than those of a supercritical coal-fired plant and 25% less than the emissions of NG CC.

Sign in / Sign up

Export Citation Format

Share Document