The Kiviter process is an above ground retorting technology for
shale oil extraction
Shale oil extraction is an industrial process for unconventional oil production. This process converts kerogen in oil shale into shale oil by pyrolysis, hydrogenation, or thermal dissolution. The resultant shale oil is used as fuel oil or up ...
.
History
The Kiviter process is based on the earlier vertical retort technology (Pintsch's generator).
[ This technology underwent a long process of development. The early concept of central inlet of the heat carrier was later replaced by a concept of heat carrier gas cross flow in the retort.][
The Kiviter technology has been used in Estonia since 1921, when first experimental Kiviter retorts were built.][
] The first commercial scale oil plant based on the Kiviter technology was built in 1924.[
][
][
]
Technology
The Kiviter process is classified as an internal combustion technology.[
] To supply heat, gases (including produced 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 shale ...
) and carbonaceous
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up ...
spent residue are burnt within the retort. Raw oil shale is fed into the top of the retort, and is heated by the rising gases, which pass laterally through the descending oil shale causing decomposition of the rock. Pyrolysis is completed in the lower section of the retort, where the spent shale contacted with more hot gas, steam and air is heated to about to gasify and burn the residual carbon ( char). 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 oil c ...
vapors and evolving gases are delivered to a condensing system, where condensed shale oil is collected, while non-condensable gases are fed back to the retort. Recycled gas enters the bottom of the retort and cools the spent shale, which then leaves the retort through a water-sealed discharge system.[
]
The Kiviter process uses large amounts of water, which is polluted during processing, and the solid waste residue contains water-soluble toxic substances that leach into the surrounding area.[
]
Commercial use
The Kiviter process is used by the Estonian Viru Keemia Grupp
Viru Keemia Grupp (VKG) is an Estonian holding group of oil shale industry, power generation, and public utility companies.
History
After Estonia gained independence, the state owned oil shale enterprise, Riigi Põlevkivitööstus ( en, Eston ...
's subsidiary VKG Oil.[
] The company operates several Kiviter retorts, the largest of them having a processing capacity of 40 tonnes per hour of oil shale feedstock.[
]
See also
* Oil shale in Estonia
There are two kinds of oil shale in Estonia, both of which are sedimentary rocks laid down during the Ordovician geologic period.
Graptolitic argillite is the larger oil shale resource, but, because its organic matter content is relative ...
* Alberta Taciuk Process
* Petrosix
Petrosix is the world's largest surface oil shale pyrolysis retort with an diameter vertical shaft kiln, operational since 1992. It is located in São Mateus do Sul, Brazil, and it is owned and operated by the Brazil energy company Petrobras. Pet ...
* Galoter process
The Galoter process (also known as TSK, UTT, or SHC; its newest modifications are called Enefit and Petroter) is a shale oil extraction technology for a production of shale oil, a type of synthetic crude oil. In this process, the oil shale is d ...
* TOSCO II process
The TOSCO II process is an above ground retorting technology for shale oil extraction, which uses fine particles of oil shale that are heated in a rotating kiln. The particularity of this process is that it use hot ceramic balls for the heat tran ...
* Fushun process
The Fushun process is an above-ground retorting technology for shale oil extraction. It is named after the main production site of Fushun, Liaoning province in northeastern China.
History
The Fushun process was developed and utilized for the extra ...
* Paraho process
The Paraho process is an above ground retorting technology for shale oil extraction. The name "Paraho" is delivered from the words "''para homem''", which means in Portuguese "for mankind".
History
The Paraho process was invented by John B. Jones, ...
References
{{Reflist
Oil shale technology
Oil shale in Estonia