Karrick process
Encyclopedia
Carbonization
Carbonization or carbonisation is the term for the conversion of an organic substance into carbon or a carbon-containing residue through pyrolysis or destructive distillation. It is often used in organic chemistry with reference to the generation of coal gas and coal tar from raw coal...
(LTC) and pyrolysis
Pyrolysis
Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible...
process of carbonaceous materials. Although primarily meant for coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
carbonization
Carbonization
Carbonization or carbonisation is the term for the conversion of an organic substance into carbon or a carbon-containing residue through pyrolysis or destructive distillation. It is often used in organic chemistry with reference to the generation of coal gas and coal tar from raw coal...
, it also could be used for processing of oil shale
Oil shale
Oil shale, an organic-rich fine-grained sedimentary rock, contains significant amounts of kerogen from which liquid hydrocarbons called shale oil can be produced...
, lignite
Lignite
Lignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad,is a soft brown fuel with characteristics that put it somewhere between coal and peat...
or any carbonaceous materials. These are heated at 450 °C (842 °F) to 700 °C (1,292 °F) in the absence of air to distill
Distillation
Distillation is a method of separating mixtures based on differences in volatilities of components in a boiling liquid mixture. Distillation is a unit operation, or a physical separation process, and not a chemical reaction....
out synthetic fuel
Synthetic fuel
Synthetic fuel or synfuel is a liquid fuel obtained from coal, natural gas, oil shale, or biomass. It may also refer to fuels derived from other solids such as plastics or rubber waste. It may also refer to gaseous fuels produced in a similar way...
s–unconventional oil and syngas
Syngas
Syngas is the name given to a gas mixture that contains varying amounts of carbon monoxide and hydrogen. Examples of production methods include steam reforming of natural gas or liquid hydrocarbons to produce hydrogen, the gasification of coal, biomass, and in some types of waste-to-energy...
. It could be used for a coal liquefaction
Coal liquefaction
-Methods:The liquefaction processes are classified as direct conversion to liquids processes and indirect conversion to liquids processeses. Direct processes are carbonization and hydrogenation.-Pyrolysis and carbonization processes:...
as also for a semi-coke production. The process was the work of oil shale technologist Lewis Cass Karrick
Lewis Karrick
Lewis Cass Karrick was an American petroleum refinery engineer, oil shale and coal technologist, and inventor. He patented several coal and oil shale related inventions, and he also refined and perfected a low-temperature carbonization and pyrolysis process for processing coal and other...
at the United States Bureau of Mines
United States Bureau of Mines
For most of the 20th century, the U.S. Bureau of Mines was the primary United States Government agency conducting scientific research and disseminating information on the extraction, processing, use, and conservation of mineral resources.- Summary :...
in the 1920s.
History
The Karrick process was invented by Lewis Cass Karrick in the 1920s. Although Karrick did not invent coal LTC as such, he perfected the existing technologies resulting the Karrick process. The retort used for the Karrick process based on the Nevada–Texas–Utah RetortNevada–Texas–Utah Retort
The Nevada–Texas–Utah Retort process was an above ground shale oil extraction technology to produce shale oil, a type of synthetic crude oil. It heated oil shale in a sealed vessel causing its decomposition into shale oil, oil shale gas and spent residue...
, used for the shale oil extraction.
In 1935, a Karrick LTC pilot plant was constructed in the coal research laboratory at the University of Utah
University of Utah
The University of Utah, also known as the U or the U of U, is a public, coeducational research university in Salt Lake City, Utah, United States. The university was established in 1850 as the University of Deseret by the General Assembly of the provisional State of Deseret, making it Utah's oldest...
. Commercial-size processing plants were operated during 1930s in Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
, Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
and Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...
. During World War II, similar processing plant was operated by the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
. In Australia, during World War II the Karrick process plants were used for shale oil extraction in New South Wales. In 1950s–1970s, the technology was used by the Rexco Company in its Snibston plant at Coalville
Coalville
Coalville is a town in North West Leicestershire, England, with a population estimated in 2003 to be almost 33,000. It is situated on the A511 trunk road between Leicester and Burton upon Trent, close to junction 22 of the M1 motorway where the A511 meets the A50 between Ashby-de-la-Zouch and...
in Leicestershire
Leicestershire
Leicestershire is a landlocked county in the English Midlands. It takes its name from the heavily populated City of Leicester, traditionally its administrative centre, although the City of Leicester unitary authority is today administered separately from the rest of Leicestershire...
, England.
Process
The Karrick process is a low-temperature carbonizationCarbonization
Carbonization or carbonisation is the term for the conversion of an organic substance into carbon or a carbon-containing residue through pyrolysis or destructive distillation. It is often used in organic chemistry with reference to the generation of coal gas and coal tar from raw coal...
process, which uses a hermetic retort. For commercial scale production, a retort about 3 foot (0.9144 m) in diameter and 20 feet (6.1 m) high would be used. The process of carbonization would last about 3 hours.
Superheated steam is injected continuously into the top of retort filled by coal. At first, in contact with cool coal, the steam condenses to water acting as a cleaning agent. While temperature of coal rises, the destructive distillation
Destructive distillation
Destructive distillation is the chemical process involving the decomposition of feedstock by heating to a high temperature; the term generally applies to processing of organic material in the absence of air or in the presence of limited amounts of oxygen or other reagents, catalysts, or solvents,...
starts. Coal is heated at 450 °C (842 °F) to 700 °C (1,292 °F) in the absence of air. The carbonization temperature is lower compared with 800 °C (1,472 °F) to 1000 °C (1,832 °F) for producing metallurgic coke. The lower temperature optimizes the production of coal tar
Coal tar
Coal tar is a brown or black liquid of extremely high viscosity, which smells of naphthalene and aromatic hydrocarbons. Coal tar is among the by-products when coal iscarbonized to make coke or gasified to make coal gas...
s richer in lighter hydrocarbons than normal coal tar, and therefore it is suitable for processing into fuels. Resulting water, oil and coal tar, and syngas moves out from retort through outlet valve
Valve
A valve is a device that regulates, directs or controls the flow of a fluid by opening, closing, or partially obstructing various passageways. Valves are technically pipe fittings, but are usually discussed as a separate category...
s at the bottom of the retort. The residue (char
Char
Char is the solid material that remains after light gases and tar coal tar have been driven out or released from a carbonaceous material during the initial stage of combustion, which is known as carbonization, charring, devolatilization or pyrolysis.Further stages of efficient combustion are...
or semi-coke) remains in the retort. While the produced liquids are mostly a by-product, the semi-coke is the main product, a solid and smokeless fuel.
The Karrick LTC process generates no carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
.
Products
In the Karrick process, 1 short tonShort ton
The short ton is a unit of mass equal to . In the United States it is often called simply ton without distinguishing it from the metric ton or the long ton ; rather, the other two are specifically noted. There are, however, some U.S...
of coal yields up to 1 barrel of oils and coal tars (12% by weight), and produces 3000 cubic feet (85 m³) of rich coal gas
Coal gas
Coal gas is a flammable gaseous fuel made by the destructive distillation of coal containing a variety of calorific gases including hydrogen, carbon monoxide, methane and volatile hydrocarbons together with small quantities of non-calorific gases such as carbon dioxide and nitrogen...
and 1500 pounds (680.4 kg) of solid smokeless char
Char
Char is the solid material that remains after light gases and tar coal tar have been driven out or released from a carbonaceous material during the initial stage of combustion, which is known as carbonization, charring, devolatilization or pyrolysis.Further stages of efficient combustion are...
or semi-coke (for one metric ton, 0.175 m³ of oils and coal tars, 95 m³ of gas, and 750 kg of semi-coke). Yields by volume of approximately 25% gasoline
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...
, 10% kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...
and 20% good quality fuel oil
Fuel oil
Fuel oil is a fraction obtained from petroleum distillation, either as a distillate or a residue. Broadly speaking, fuel oil is any liquid petroleum product that is burned in a furnace or boiler for the generation of heat or used in an engine for the generation of power, except oils having a flash...
are obtainable from coal. Gasoline obtained from coal by the Karrick process combined with cracking and refining is equal in quality to tetraethyl lead gasolines. More power is developed in internal combustion engines and an increase in fuel economy of approximately 20% is obtainable under identical operating conditions.
Semi-coke can be used for utility boilers and cooking coal in steel smelters, yields more heat than raw coal and can be converted to water gas
Water gas
Water gas is a synthesis gas, containing carbon monoxide and hydrogen. It is a useful product but requires careful handling because of the risk of carbon monoxide poisoning. The gas is made by passing steam over a red-hot hydrocarbon fuel such as coke:...
. Water gas can be converted to oil by the Fischer-Tropsch process
Fischer-Tropsch process
The Fischer–Tropsch process is a set of chemical reactions that convert a mixture of carbon monoxide and hydrogen into liquid hydrocarbons. The process, a key component of gas to liquids technology, produces a petroleum substitute, typically from coal, natural gas, or biomass for use as synthetic...
. Coal gas
Coal gas
Coal gas is a flammable gaseous fuel made by the destructive distillation of coal containing a variety of calorific gases including hydrogen, carbon monoxide, methane and volatile hydrocarbons together with small quantities of non-calorific gases such as carbon dioxide and nitrogen...
from Karrick LTC yields greater energy content
Energy density
Energy density is a term used for the amount of energy stored in a given system or region of space per unit volume. Often only the useful or extractable energy is quantified, which is to say that chemically inaccessible energy such as rest mass energy is ignored...
than natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
. Phenolic
Phenol
Phenol, also known as carbolic acid, phenic acid, is an organic compound with the chemical formula C6H5OH. It is a white crystalline solid. The molecule consists of a phenyl , bonded to a hydroxyl group. It is produced on a large scale as a precursor to many materials and useful compounds...
wastes are used by the chemical industry as feedstock for plastics, etc. Electrical power can be cogenerated at nominal equipment cost.
Economic viability
Oils, including petroleum, have long been extracted from coal. Production plants were merely shut down in the 1880s because crude oil became cheaper than coal liquefaction. The capability itself, however, has never disappeared. Eight years of pilot plant tests by Karrick attest that states, cities or even smaller towns, could make their own gas and generate their own electricity.A 30 ton plant and oil refinery will show a profit over and above all operating and capital costs and the products will sell at attractive prices for equivalent products. The private sector should require no subsidies, but not in competition with those who skim off the oil from coal and sell the residual smokeless fuel to power plants.}
The cheapest liquid fuel from coal will come when processed by LTC for both liquid fuels and electric power. As a tertiary product of the coal distilling process, electrical energy can be generated at a minimum equipment cost. A Karrick LTC plant with 1 kiloton of daily coal capacity produces sufficient steam to generate 100,000 kilowatt hours of electrical power at no extra cost excepting capital investment for electrical equipment and loss of steam temperature passing through turbines. The process steam cost could be low since this steam could be derived from off-peak boiler capacity or from turbines in central electric stations. Fuel for steam and superheating would subsequently be reduced in cost.
Advantages and disadvantages
Compared to the Bergius processBergius process
The Bergius Process is a method of production of liquid hydrocarbons for use as synthetic fuel by hydrogenation of high-volatile bituminous coal at high temperature and pressure...
, the Karrick process is cheaper, requires less water and destroys less the thermal value (one-half that of the Bergius process). The smokeless semi-coke fuel, when burned in an open grate or in boilers, delivers 20% to 25% more heat than raw coal. The coal gas should deliver more heat than natural gas per heat unit contained due to the greater quantity of combined carbon and lower dilution of the combustion gases with water vapor.
See also
- Coal oilCoal oilCoal oil is a term once used for a specific shale oil used for illuminating purposes. Coal oil is obtained from the destructive distillation of cannel coal, mineral wax, and bituminous shale, while kerosene is obtained by the distillation of petroleum...
- Carbon sequestration
- CO2 sequestrationCO2 sequestrationCarbon sequestration is the capture of carbon dioxide and may refer specifically to:* "The process of removing carbon from the atmosphere and depositing it in a reservoir." When carried out deliberately, this may also be referred to as carbon dioxide removal, which is a form of geoengineering.*...
- Carbon capture and storageCarbon capture and storageCarbon capture and storage , alternatively referred to as carbon capture and sequestration, is a technology to prevent large quantities of from being released into the atmosphere from the use of fossil fuel in power generation and other industries. It is often regarded as a means of mitigating...
- Major coal producing regions
- Pyrolysis oilPyrolysis oilPyrolysis oil is a synthetic fuel under investigation as substitute for petroleum. It is extracted by biomass to liquid technology of destructive distillation from dried biomass in a reactor at temperature of about 500°C with subsequent cooling. Pyrolytic oil is a kind of tar and normally contains...
- Synthetic Liquid Fuels ProgramSynthetic Liquid Fuels ProgramThe Synthetic Liquid Fuels Program was a program run by the United States Bureau of Mines to create the technology to produce synthetic fuel from coal. It was initiated in 1944 during World War II...
- Synthetic fuels in the United StatesSynthetic fuels in the United StatesSynthetic fuels in the United States is an issue of rising importance due the crude oil prices, and geopolitical and economic considerations.-History:...
- Synthetic oilSynthetic oilSynthetic oil is a lubricant consisting of chemical compounds that are artificially made . Synthetic lubricants can be manufactured using chemically modified petroleum components rather than whole crude oil, but can also be synthesized from other raw materials...
External links
- A magic way to make billions (TIME Magazine, February 2006)
- China to Invest $128 Billion to Develop Coal-Based Synthetic Fuels
- Military's push to turn coal into fuel picking up speed (Associated Press)
- Princeton University: Increased Automobile Fuel Efficiency and Synthetic Fuels; Alternatives for Reducing Oil Imports (PDF)
- The Bureau of Mines Synthetic Liquid Fuels Program 1944-55 Part 1 Oil From Coal
- The Early Days of Coal Research at the U.S. Department of EnergyUnited States Department of EnergyThe United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
site.