<kuid:142675:1387> lignite briquette factory (Kappenrode)

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In some regions of Germany, lignite mining can be traced back into the late middle ages. Until the mid 19th century, however, its use as a fuel was restricted to lignite mining regions where alternative fuels like black coal or fire wood had to be brought in over great distances. The unpopularity of lignite as a fuel results from its brittleness and a water content of up to 60% in freshly mined lignite. After air drying it tends to form a dust with an exceptionally low flash point, which is liable to self-ignition. Some qualities of lignite also have a very high content in ashes and salts.
Nevertheless, presence of large deposits of lignite found in some parts of Germany, local shortages in fire wood and long transport distances to black coal mining areas led to continuing attempts to find economically viable uses for lignite.
The ultimate solutions were the production of lignite briquettes, starting in mid-19th century, production of electricity in lignite fuelled power plants since the beginning of the 20th century as well as synthesis of hydrocarbons for production of synthetic fuel and plastics between approximately 1925 and the downfall of the communist regime in 1989.
In order to reduce transportation cost, most large scale users of raw lignite are located in the vicinity of lignite opencast mines, from where it can be hauled directly from the excavators by mining trains. Raw lignite is unloaded from hopper cars into intermediate bunkers, from where it is almost immediatly transferred to the processing plants. The close distance to the mines eliminates the need to maintain large storage areas, typically found with power plants and coke factories using black coal.
Since mining trains cannot run on regular railway tracks, raw lignite destined for more distant customers has to be transferred to normal trains. It is economically sensible to add such transfer capabilities wherever possible to production plants which are regularly receiving large quantities of raw lignite. Manufacture of lignite briquettes requires large amounts of steam for the driers and presses. The steam is produced in large boiler houses, with lignite fuelled furnaces. It is therefore quite easy to install steam turbines to generate electricity as well. It is common practice for production plants posessing large power plants, to supply neighboring factories with steam and other energies.
To produce briquettes, lignite is milled to a uniform particle size. The coarse powder is then dried to a water content of about 15%. The steam heated driers make the bulk of the machinery. The dried powder is compacted to briquettes in a steam powered press. At each stroke a given amount of powder is filled into a mold and pressed by a piston into a long cylinder with slightly tapering bore. The bore is approximately rectangular which determines the shape of the final product. As the material is squeezed through the bore pressure increases. Due to their high content of tar, the lignite particles stick together giving rise to a hard briquette. During drying and compacting at high pressure the briquettes are getting hot. In order to prevent self ignition, the briquettes must be cooled prior to storage and shipment. Therefore each briquette press is linked by its own conveyor belt with a central cooling facility. In this facility briquettes are moved by a system of conveyor belts long enough through open air to cool to ambient temperature. From there the cooled briquettes are transported to a facility for loading traincars.
Because of the cheaply produced steam, briquette factories became a domain for fireless locomotives, which performed shunting duties at the associated rail yards.
As an industry asset, the lignite briquette factory receives raw lignite and either transfers it to other traincars or converts it into briquettes, which can be loaded into traincars. Ashes produced during these processes is collected in the ash-bunker, from where it can be loaded into enabled traincars. Although incorrect this asset was also enabled to handle the Auran coal product instead of the lignite product.