The Shell ''in situ'' conversion process (Shell ICP) is an ''
in situ
''In situ'' (; often not italicized in English) is a Latin phrase that translates literally to "on site" or "in position." It can mean "locally", "on site", "on the premises", or "in place" to describe where an event takes place and is used in ...
''
shale oil extraction technology to convert
kerogen
Kerogen is solid, insoluble organic matter in sedimentary rocks. Comprising an estimated 1016 tons of carbon, it is the most abundant source of organic compounds on earth, exceeding the total organic content of living matter 10,000-fold. It ...
in
oil shale
Oil shale is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general composition of oil shales constitu ...
to
shale oil
Shale oil is an unconventional oil produced from oil shale rock fragments by pyrolysis, hydrogenation, or thermal dissolution. These processes convert the organic matter within the rock ( kerogen) into synthetic oil and gas. The resulting o ...
. It is developed by the
Shell Oil Company
Shell USA, Inc. (formerly Shell Oil Company, Inc.) is the United States-based wholly owned subsidiary of Shell plc, a UK-based transnational corporation "oil major" which is amongst the largest oil companies in the world. Approximately 18,000 ...
.
History
Shell's ''in situ'' conversion process has been under development since the early 1980s.
[
] In 1997, the first small scale test was conducted on the Mahogany property test site, located west of
Denver
Denver () is a consolidated city and county, the capital, and most populous city of the U.S. state of Colorado. Its population was 715,522 at the 2020 census, a 19.22% increase since 2010. It is the 19th-most populous city in the United ...
on
Colorado's Western Slope in the
Piceance Creek Basin
The Piceance Basin is a geologic structural basin in northwestern Colorado, in the United States. It includes geologic formations from Cambrian to Holocene in age, but the thickest section is made up of rocks from the Cretaceous Period. The basi ...
. Since 2000, additional research and development activities have carried on as a part of the Mahogany Research Project.
[ The oil shale heating at Mahogany started early 2004.][
] From this test site, Shell has recovered of shale oil.[
]
Process
The process heats sections of the vast oil shale field ''in situ'', releasing the shale oil and oil shale gas Oil shale gas (also: retort gas or retorting gas) is a synthetic non-condensable gas mixture (syngas) produced by oil shale thermal processing ( pyrolysis). Although often referred to as shale gas, it differs from the natural gas produced from sha ...
from the rock so that it can be pumped to the surface and made into fuel
A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy bu ...
. In this process, a freeze wall is first to be constructed to isolate the processing area from surrounding groundwater.[ To maximize the functionality of the freeze walls, adjacent working zones will be developed in succession. wells, eight feet apart, are drilled and filled with a circulating super-chilled liquid to cool the ground to .][
] Water is then removed from the working zone. Heating and recovery wells are drilled at intervals within the working zone. Electrical heating element
A heating element converts electrical energy into heat through the process of Joule heating. Electric current through the element encounters resistance, resulting in heating of the element. Unlike the Peltier effect, this process is independe ...
s are lowered into the heating wells and used to heat oil shale to between and over a period of approximately four years.[
][ ]Kerogen
Kerogen is solid, insoluble organic matter in sedimentary rocks. Comprising an estimated 1016 tons of carbon, it is the most abundant source of organic compounds on earth, exceeding the total organic content of living matter 10,000-fold. It ...
in oil shale is slowly converted into shale oil and gases, which then flow to the surface through recovery wells.[
][
]
Energy consumption
A RAND study in 2005 estimated that production of of oil (5.4 million tons/year) would theoretically require a dedicated power generating capacity of 1.2 gigawatts (10 billion kWh/year), assuming deposit richness of per ton, with 100% pyrolysis efficiency, and 100% extraction of pyrolysis products.[ If this amount of electricity were to be generated by a coal-fired power plant, it would consume five million ton of coal annually (about 2.2 million toe).][
]
In 2006, Shell estimated that over the project life cycle, for every unit of energy consumed, three to four units would be produced.[ Such an "]energy returned on energy invested
In energy economics and ecological energetics, energy return on investment (EROI), also sometimes called energy returned on energy invested (ERoEI), is the ratio of the amount of usable energy (the ''exergy'') delivered from a particular energy ...
" would be significantly better than that achieved in the Mahogany trials. For the 1996 trial, Shell applied 440,000 kWh (which would require about 96 toe energy input in a coal-fired plant), to generate of oil (37 toe output).
Environmental impacts
Shell's underground conversion process requires significant development on the surface. The separation between drilled wells is less than five meters and wells must be connected by electrical wiring and by piping to storage and processing facilities. Shell estimates that the footprint of extraction operations would be similar to that for conventional oil and gas drilling.[
] However, the dimensions of Shell's 2005 trial indicate that a much larger footprint is required. Production of 50,000 bbl/day would require that land be developed at a rate on the order of per year.
Extensive water use and the risk of groundwater pollution
Groundwater pollution (also called groundwater contamination) occurs when pollutants are released to the ground and make their way into groundwater. This type of water pollution can also occur naturally due to the presence of a minor and unwan ...
are the technology's greatest challenges.[
]
Current implementations
In 2006, Shell received a Bureau of Land Management lease to pursue a large demonstration with a capacity of ; Shell has since dropped those plans and is planning a test based on ICP that would produce a total of minimum , together with nahcolite, over a seven-year period.[
]
In Israel, IEI, a subsidiary of IDT Corp. is planning a shale pilot based on ICP technology. The project would produce a total of 1,500 barrels. However, IEI has also announced that any subsequent projects would not use ICP technology, but would instead utilize horizontal wells and hot gas heating methods.
In Jordan, Shell subsidiary JOSCO plans to use ICP technology to achieve commercial production by the "late 2020s."[
] In October, 2011, it was reported that JOSCO had drilled more than 100 test holes over the prior two years, apparently for the sake of testing shale samples.[
]
The Mahogany Oil Shale Project has been abandoned by Shell in 2013 due to unfavorable project economics [ Denver Post. Available in: Page visited on 30 May 2015.]
See also
* Chevron CRUSH
Chevron CRUSH is an experimental ''in situ'' shale oil extraction technology to convert kerogen in oil shale to shale oil. The name stands for Chevron's Technology for the Recovery and Upgrading of Oil from Shale. It is developed jointly by Chevro ...
* ExxonMobil Electrofrac
ExxonMobil Electrofrac is an ''in situ'' shale oil extraction technology proposed by ExxonMobil for converting kerogen in oil shale to shale oil.
Technology
ExxonMobil Electrofrac uses a series of fractures created in the oil shale formation. Pre ...
References
External links
Mahogany Research Project
{{shell oil
Oil shale technology
Shell plc
1997 introductions