Remote Gas PDF Print E-mail
Molecularly, remote gas is typically very similar to crude oil based fuels (LP, LPG or Diesel Fuel), except they remain in their natural or “pre-fining” state and include impurities like sulfur, hydrogen and water. The utilization of these gases for creating electricity “on the spot” (or remotely) via distributed generation or CHP micro turbine plants is very desirous since the cost and environmental burden of the refining process can be precluded all together. Prior to the utilization of micro turbines, all of these types of gases had to be either flared, processed (refined) or kept in the ground.

Coal Bed Methane: coalbed gas is a form of natural gas extracted from coal beds. In recent decades it has become an important source of energy in United States, Canada, and other countries. Australia has rich deposits where it is known as coal seam gas. The term refers to methane adsorbed into the solid matrix of the coal. It is called 'sweet gas' because of its lack of hydrogen sulfide. Coalbed methane, often referred to as CBM, is distinct from a typical sandstone or other conventional gas reservoir, as the methane is stored within the coal by a process called adsorption. The methane is in a near-liquid state, lining the inside of pores within the coal (called the matrix). The open fractures in the coal (called the cleats) can also contain free gas or can be saturated with water. Often water must be drained off CBM fields to liberate the gas. CBM can rather expensive to develop due to the cost associated with running electric power (to run water pumps and compressors) to the remote fields and to also remove the water. However, Preon has successfully build custom “skids” that contain multiple micro turbines. These skids are powered by the raw CBM gas itself to create electric power with very low emissions (lower by a factor of 20 compared to diesel gensets). This precludes the environmental impact of running electric wires through pristine remote lands and diesel fuel trucks kicking up dust. The cost of electric power generated by CBM is about 1/5th the cost of diesel electric power and is consistent with the cost of utility electric via a central coal-fired plant. CBM is considered “pipeline quality” (same as processed/refined methane or wellhead gas) if it does not contain less than 92% methane. The predominant CBM play in the US is the Powder River Play in northeast Wyoming. Preon services this area with our engineering office in Sheridan Wyoming. However, CBM plays are found all over the US and are predominant in Oklahoma, Nebraska and Alabama.

Shale Gas: is natural gas produced from shale. The DOE has recently (June 2009) INCREASED the US reserves of in-ground natural gas by 35% - this is a remarkable change from our annual ½% decline in natural gas reserves. The increase was due to the inclusion of shale gas in the reserves – shale gas is “deep” gas often at 4,000 feet and deeper. Prior to advancement in drilling technologies, this gas was through to be too costly to develop. The Barack Obama administration in the US believes that increased shale gas development will help reduce greenhouse gas emissions. Because shales ordinarily have insufficient permeability to allow significant fluid flow to a well bore, most shales are not commercial sources of natural gas. Shale has low matrix permeability, so gas production in commercial quantities requires fractures to provide permeability. Shale gas has been produced for years from shales with natural fractures; the shale gas boom in recent years has been due to modern technology in hydraulic fracturing to create extensive artificial fractures around well bores. Horizontal drilling is often used with shale gas wells, with lateral lengths up to 5,000 feet within the shale, to create maximum borehole surface area in contact with the shale. Shale gas has some of the same environmental and economic limitations of CBM: impact of running electrical wires a long distance and water control/pollution. Preon is in discussions with private businesses in southern Illinois to utilize gas skids similar to those used in CBM for shale gas. Shale gas is predominant in Southern Illinois/Indiana, Wyoming, Texas, Ohio, Pennsylvania and West Virginia. It has been estimated that by 2020, 50% of all US gas consumption will be shale gas.

Conventional Gas or Natural Gas: Natural gas is often described as the cleanest fossil fuel, producing less carbon dioxide per joule delivered than either coal or oil and far fewer pollutants than other fossil fuels. Oil and natural gas are produced by the same geological process: anaerobic decay of organic matter deep under the Earth's surface. As a consequence, oil and natural gas are often found together. In common usage, deposits rich in oil are known as oil fields, and deposits rich in natural gas are called natural gas fields. In general, organic sediments buried in depths of 3,000 to 20,000 feet to generate oil, while sediments buried deeper and at higher temperatures generate natural gas. The deeper the source, the "drier" the gas (that is, the smaller the proportion of condensates in the gas). Because both oil and natural gas are lighter than water, they tend to rise from their sources until they either seep to the surface or are trapped by a non-permeable layer of rock. They can be extracted from the trap by drilling. Conventional gas fields are the first “remote” gas fields to be developed since the challenges of removing contaminants and water are precluded and the life/volume of a well can be considerably longer than CBM or shale gas. Conventional gas fields contain nearly 100% CH4. When gas prices are low, sometimes conventional gas wells may be the only economic producers. Preon has recently designed, built and commissioned custom micro turbine skids for XTO Energy – acquired recently by Exxon Mobile. The predominant natural gas fields in the US are in Oklahoma, Texas, Louisiana, Ohio, Pennsylvania and West Virginia as well as the mountain states.

Flare Gas: Flare gas is often gas that is deliberately vented at refining, oil and chemical operations to avoid an over-pressure event on pipes, vessels and containers. The pre-combusted gas is mainly methane that is deliberately ignited to preclude methane (CH4) versus carbon dioxide (CO2) from reaching the atmosphere. Methane causes 23 times as much “greenhouse” damage compared to carbon dioxide. 10 countries account for 75% of all the gas flaring in the world. Russia and Nigeria are the worse contributors: Nigeria river delta is flaring 2.5 billion cubic feet of gas a day. Flaring is often an effect of a scenario where crude oil is recovered but there is no local use for the gas or lacking gas transport pipe infrastructure. Preon is part owner of Preon Nigeria LLC and is working with Nigeria Delta Development Initiative to bring a cooperative spirit to the Communities in the Delta area so that utilization of the Preon Flare Gas Module™ can bring environmental and economic relief to this underdeveloped region. The Preon Flare Gas Module™ is an iteration of the custom micro turbine skids that Preon has successfully dispatched for CBM and natural gas fields.