Adler Diplomat in WW II with wood gas generator

Producer gas is fuel gas that is manufactured by blowing a coke or coal with air and steam simultaneously.[1] It mainly consists of carbon monoxide (CO), hydrogen (H2), as well as substantial amounts of nitrogen (N2). The caloric value of the producer gas is low (mainly because of its high nitrogen content), and the technology is obsolete. Improvements over producer gas, also obsolete, include water gas where the solid fuel is treated intermittently with air and steam and, far more efficiently synthesis gas where the solid fuel is replaced with methane.

In the USA, producer gas may also be referred to by other names based on the fuel used for production such as wood gas. Producer gas may also be referred to as suction gas. The term suction refers to the way the air was drawn into the gas generator by an internal combustion engine. Wood gas is produced in a gasifier


Producer gas is generally made from coke, or other carbonaceous material[2] such as anthracite. Air is passed over the red-hot carbonaceous fuel and carbon monoxide is produced. The reaction is exothermic and proceeds as follows:

Formation of producer gas from air and carbon:

C + O2 → CO2, +97,600 calories/mol
CO2 + C → 2CO, –38,800 calories/mol (mol of the reaction formula)
2C + O2 → 2CO, +58,800 calories/mol (per mol of O2 i.e. per mol of the reaction formula)

Reactions between steam and carbon:

H2O + C → H2 + CO, –28,800 calories/mol (presumably mol of the reaction formula)
2H2O + C → 2H2 + CO2, –18,800 calories/mol (presumably mol of the reaction formula)

Reaction between steam and carbon monoxide:

H2O + CO → CO2 + H2, +10,000 calories/mol (presumably mol of the reaction formula)
CO2 + H2 → CO + H2O, –10,000 calories/mol (presumably mol of the reaction formula)

The average composition of ordinary producer gas according to Latta was: CO2: 5.8%; O2: 1.3%; CO: 19.8%; H2: 15.1%; CH4: 1.3%; N2: 56.7%; B.T.U. gross per cu.ft 136 [3][4] The concentration of carbon monoxide in the "ideal" producer gas was considered to be 34.7% carbon monoxide (carbonic oxide) and 65.3% nitrogen.[5] After "scrubbing", to remove tar, the gas may be used to power gas turbines (which are well-suited to fuels of low calorific value), spark ignited engines (where 100% petrol fuel replacement is possible) or diesel internal combustion engines (where 15% to 40% of the original diesel fuel requirement is still used to ignite the gas [6]). During World War II in Britain, plants were built in the form of trailers for towing behind commercial vehicles, especially buses, to supply gas as a replacement for petrol (gasoline) fuel.[7] A range of about 80 miles for every charge of anthracite was achieved.[8]

In old movies and stories, when describing suicide by "turning on the gas" and leaving an oven door open without lighting the flame, the reference was to coal gas or town gas. As this gas contained a significant amount of carbon monoxide it was quite toxic. Most town gas was also odorized, if it did not have its own odor. Modern 'natural gas' used in homes is far less toxic, and has a mercaptan added to it for odor for identifying leaks.

Various names are used for producer gas, air gas and water gas generally depending on the fuel source, process or end use including:

Other similar fuel gasses

Uses and Advantages of Producer Gas:

See also


  1. ^ Hiller, Heinz; Reimert, Rainer; Stönner, Hans-Martin (2011). "Gas Production, 1. Introduction". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a12_169.pub3. ISBN 978-3527306732.
  2. ^ "PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES (synthesis gas from liquid or gaseous hydrocarbons C01B; underground gasification of minerals E21BÂ 43/295); CARBURETTING AIR OR OTHER GASES" (PDF).
  3. ^ Nisbet Latta, "American Producer Gas Practice and Industrial Gas Engineering", D. Van Nostrand Company, 1910 , page 107
  4. ^ Latta, Nisbet (1910). American Producer Gas Practice and Industrial Gas Engineering. D. Van Nostrand Company. American producer gas practice and industrial gas engineering.
  5. ^ W. J. Atkinson Butterfield, "The Chemistry of Gas Manufacture, Volume 1. Materials and Processes", Charles Griffin & Company Ltd., London, 1907, page 72
  6. ^ "Archived copy". Archived from the original on 2008-12-26. Retrieved 2008-11-18.((cite web)): CS1 maint: archived copy as title (link)
  7. ^ Staff (16 July 1941). "Producer gas for transport". Parliamentary Debates. Hansard. Retrieved 15 November 2008.
  8. ^ Taylor, Sheila (2001). The Moving Metropolis. London: Calmann and King. p. 258. ISBN 1-85669-241-8.
  9. ^ CONVERSION OF SOLID FUELS TO LOW BTU GAS Thomas E. Ban McDowell-Wellman Engineering Company Cleveland, Ohio 44110
  10. ^ Proceedings of the American Gas Light Association. American Gas Light Association. 1881 – via Google Books.