LLNL HRS (hot recycled solid) process is an above-ground
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 ...
technology. It is classified as a hot recycled solids technology.
History
The process was developed by the
Lawrence Livermore National Laboratory
Lawrence Livermore National Laboratory (LLNL) is a Federally funded research and development centers, federally funded research and development center in Livermore, California, United States. Originally established in 1952, the laboratory now i ...
. In 1984–1987, Lawrence Livermore National Laboratory operated a LLNL HRS process-based pilot pant at
Parachute, Colorado
Parachute is a home rule municipality in Garfield County, Colorado, United States. The population was 1,390 at the 2020 census.
The town is the birthplace of Willard Libby, recipient of the 1960 Nobel Prize in Chemistry.
History
The town's ...
, with capacity of one tonne of oil shale per day. In 1989, the pilot plant was upgraded to process four tonne of oil shale per day. The pilot plant was operated till 1993.
[
] Later the process was modified and tested in the field of waste treatment and environmental cleanup for removing organic compounds and for decomposing
sodium nitrate
Sodium nitrate is the chemical compound with the chemical formula, formula . This alkali metal nitrate salt (chemistry), salt is also known as Chile saltpeter (large deposits of which were historically mined in Chile) to distinguish it from ordi ...
in contaminated soils.
[
]
Process
As a heat carrier, LLNL HRS process uses
spent oil shale. Raw oil shale and spent oil shale are mixed in the
fluidized bed mixer. The use of fluidized bed mixer results in better mixture, which in turn increases the mean quantity of oil yield and oil shale throughput. From the fluidized bed mixer oil shale moves downward to the packed-bed pyrolyzer. The heat is transferred from the heated spent oil shale to the raw oil shale causing
pyrolysis
Pyrolysis is a process involving the Bond cleavage, separation of covalent bonds in organic matter by thermal decomposition within an Chemically inert, inert environment without oxygen. Etymology
The word ''pyrolysis'' is coined from the Gree ...
. As a result, oil shale decomposes 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 oil c ...
vapors,
oil shale gas and spent oil shale. Oil vapors are collected from the pyrolyzer. The spent oil shale, still including residual carbon (
char), by the air pneumatic lift pipe to the delayed-fall
combustor
A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, burner can, combustion chamber or flame holder. In a gas turbine engine, the ''combustor'' or combustion ...
where it is combusted to heat the process. The delayed-fall combustor used in this process gives greater control over the combustion process as compared to a lift pipe combustor. From the delayed-fall combustor the oil shale ash and spent shale falls into a fluidized bed classifier where the finest parts of solids are removed and hot spent shale is forwarded to the fluidized bed mixer.
[
]
See also
* Galoter process
* Alberta Taciuk Process
* Petrosix process
* Kiviter process
* TOSCO II process
* Fushun process
* Paraho process
* Lurgi-Ruhrgas process
* Chevron STB process
* KENTORT II
References
{{Reflist
Oil shale technology
Thermal treatment