Ergo Exergy - UCG

Why εUCG?

What is going on in today's energy market? Growing shortages of supply of oil and natural gas; already-high and ever-increasing fuel prices; recent signs of depletion of several major natural gas fields across the world; no breakthroughs in oil and gas exploration; and a rising tide of energy consumption in the Developing World. Furthermore, these energy market dynamics are unfolding on the background of mounting concerns about global warming.

Coal has to play a bigger role in the global energy supply - it is abundant and almost ubiquitous. Traditional environmental unease with coal use is addressed by its gasification. Coal gasification is capable of converting coal into a clean and environmentally-acceptable energy product.

Conventional coal gasification technologies, however, are more expensive than traditional coal use and uncompetitive with oil and natural gas.

The εUCG is the only coal gasification technology which is both completely clean and cost-competitive with oil, gas, and conventional coal. The process has produced commercial quantities of gas for chemical processes and power generation. The gas has been used for co-firing with pulverized coal in coal-fired boilers, and can be used in modern gas turbines with minimal modifications to the combustion system.

Chemical processing of the εUCG product gas can result in its catalytic conversion to methane, distillate liquid fuels and hydrogen - the fuels of choice for existing and emerging power generation technologies. The low capital and operating costs of underground coal gasification lead to low-cost fuels for power generation, transportation and other applications. These fuels can be produced at locations where other sources of energy are not available or viable, since εUCG can extract coal energy in conditions which render conventional mining unfeasible, be it for technical, environmental, or economic reasons.

Since εUCG uses unmined coal and takes place in underground coal seams, it saves on both coal cost and the capital cost of the gasification reactor compared to conventional gasification. The difference is so significant that εUCG syngas, a clean and convenient fuel, becomes also the most cost-competitive fuel on the market today.

Compare:

εUCG versus Conventional Coal

Technical Advantages…

  • Safer, simpler, cleaner, and more versatile resource extraction method.
  • Triples available resources: unminable coal can be recovered by εUCG.
  • Cleaner transport: gas is supplied via pipeline, not by railcar. 
  • Unlike conventional coal, εUCG can meet a zero waste disposal requirement.
  • Significant reduction in CO2 , particulates, SOx and NOx emissions
  • CO2  capture and sequestration are much more efficient and cheaper with εUCG  syngas than with conventional coal.

Economic Advantages…

  • Conventionally unminable coal becomes commercially viable.
  • Much lower capital cost.
  • Much shorter construction and commissioning time.
  • Cheaper transport of fuel product.
  • Low labor requirements, low O&M cost.
  • Low land rehabilitation cost.

εUCG versus Natural Gas

  • The εUCG process manufactures gas from coal deposits, whereas natural gas (NG) must be discovered by exploration. NG is notorious for running out well before the predicted life of the gas field. Coal reserves are easily measurable, and once εUCG gas production is proven, the plant is ready to sign a long term supply contracts guarantee. The guarantee that often proves too risky for a NG supplier.
  • Far greater available resources: it is known that there is much more energy left in the world's coal resources than there is in its oil and gas resources.
  • εUCG gas is much cheaper than NG in most energy markets.
  • A gas turbine burning εUCG gas will produce about 25% more electricity than one using NG.
  • There is a significant reduction in NOx emissions when used as fuel.
  • CO2  capture and sequestration are much more efficient with εUCG  gas than with NG.
  • εUCG gas can be catalytically converted into synthetic natural gas at a  competitive cost.

εUCG versus Coal Bed Methane

  • Coal Bed Methane (CBM) represents only a few percent of the total energy content of coal. This means that from the same square kilometer of a coal field, εUCG will produce about 25-30 times the energy that can be produced there by a CBM operation.
  • εUCG manufactures gas from coal deposits, whereas coal bed methane (CBM) must be discovered by exploration. There is much uncertainty in measuring CBM reserves. Coal reserves are easy to measure, and once εUCG gas production is proven, the plant is ready to sign a long term supply contracts guarantee. CBM is a more high-risk product.
  • Far greater available resources: not all coal fields have appreciable CBM content but all of them have coal
  •  εUCG gas is much cheaper than CBM in most energy markets.
  • A gas turbine burning εUCG gas will produce about 25% more electricity than using CBM.
  • There is a significant reduction in NOx emissions when εUCG syngas is used as fuel.
  • CO2  capture and sequestration are much more efficient with εUCG gas than with CBM.
  • CBM recovery requires pumping out large volumes of water with often dire environmental consequences, unlike εUCG which uses groundwater in its underground process and is not predicated on the pumping of water.

εUCG versus Conventional (Surface) Gasification

  • The εUCG process uses unmined coal and is performed in underground coal seams; compared to conventional gasification, it eliminates the cost of coal mining, transport and preparation, and in addition it does not require the capital cost of the surface gasification reactor. Besides, εUCG does not incur the cost of ash and slag removal, storage and disposal – all inert solids remain underground. As a result, εUCG gas is much cheaper than its conventional peers.
  • Far greater available resources: not all coal fields can be conventionally mined, but most of them can be gasified by εUCG.
  •  εUCG gas is usually produced at lower temperature and is easier to process and clean up.
  • Unlike εUCG, conventional gasification requires coal mining with all its environmental and safety problems.
  • εUCG gas normally carries much less particulates than the syngas of conventional gasification.
  • εUCG has a very large underground gas storage system; besides, each εUCG gasifier uses multiple reactors for gas production. As a result, availability of εUCG plant is normally 100% as compared to conventional gasification plants which currently struggle to reach 80% availability.
  • Conventional gasification uses large volumes of water that must be delivered to plant, whereas εUCG uses groundwater present in the coal seam, which is often, otherwise unusable. This, again, makes εUCG more economical.
  • Conducted in a chemical reactor, conventional gasification seems to be easier to control. However, εUCG underground gasifiers have demonstrated a similar consistency of gas production, with much less reliance on an operator’s intervention.

© 2015 Ergo Exergy