The Rheinisches Braunkohlerevier, often called the Rhenish mining area, is a lignite mining area or district in the Cologne Bay, on the northwestern edge of the Rhenish Slate Mountains. The mining of lignite using the open pit method has had a significant impact on the landscape here and led to the formation of several important industrial sites. The area includes the Zülpicher and Jülicher Börde, the Erft lowlands and the Ville, making it the largest lignite mining area in Europe. RWE, Presse & News, Special Braunkohle, retrieved 27 March 2010. To a lesser extent clay, silica sand and loess are mined here. The area is the only active lignite mining area in what was West Germany during German partition (all other active lignite mines in Germany are in the former east) and contains the mines with the largest surface area, greatest depth (both absolute and relative to Normalhöhennull), and biggest annual output of coal.
Today, the industrial use of the coalfield with the complete value chain from coal mining to power generation is carried out exclusively by the RWE Group (via its subsidiary RWE Power). According to current planning, mining in the Rhenish lignite mining area is secured until 2030. Forecasts about future developments are difficult, as a central pillar of the German energy turnaround is a coal phase-out.
Boundaries and division Southern District
The southern district around Brühl begins south of Brühl in the Ville, there north of a line Brühl-Eckdorf/ Erftstadt-Bliesheim. The southern district extends approximately as far as the course of the Luxemburger Straße B 265 near Hürth and Liblar and includes the former Gewerkschaft Hürtherberg mine and the present Hürtherberg recreational area. On the south side, it encloses the concessions of Carl Brendgen and his companies around Kierdorf. This area of small-scale mines had already been exhausted and recultivated by the mid-1960s. The open pits have given way to a forested recreational area with a large number of small and medium-sized lakes.
Middle district
The Middle Mining District covers the Villerücken area west of the Frechener Sprung (Frechen-Oberaußem-Niederaußem line) from the Luxemburger Strasse in the south to the Bergheim-Oberaußem line in the north. It is now largely decarbonized and recultivated, but the lignite industry with large power plants and downstream industries still characterizes the landscape.
Northern District (Nordrevier)
The northern district adjoins the seam-free Kasterer Horst and the Erft bend to the east and extends with the Garzweiler I and II opencast mines as far as Jüchen and Erkelenz, with the lignite seams extending to even greater depths below the Niers and Schwalm rivers. (PDF-Datei; 1,96 MB), retrieved 24 February 2010. It also includes parts of the Erftscholle with the Hambach deep open pit mine near Jülich. Here, overburden and coal are extracted using large equipment such as bucket wheel excavators, and the pits are then backfilled using large-scale conveyor systems and spreaders. The coal is transported to the plants in the south by a dedicated rail network (north-south railroad (Garzweiler) and Hambach railroad). The Sophienhöhe spoil heap (290 m. above sea level) towers over the Jülicher Börde, visible from afar.
Western district (Westrevier) The western coalfield between Düren, Weisweiler, Eschweiler, Alsdorf, Aldenhoven and Jülich with the former Zukunft open pit mine, BIAG Zukunft and the Inden open pit mine uses seams of the Rurscholle to supply the Weisweiler power plant.
Mining the less thick lignite seams adjacent to this area is not economically viable at present. This is all the more true as it would involve resettlement measures at the same time.
Several industrial areas around the mining area have developed based on lignite, eg the Wesseling oil refinery which developed from a coal liquefaction plant founded in 1939, or the RWE transformer and electrical substation in Brauweiler. These are usually classed as being within the district.
Border areas In addition to the above-mentioned main areas of the Rhenish mining district, there were also deposits of lignite on the eastern and southern edges of the Cologne Bay, which were also mined in some smaller pits in places until the 20th century. Geologically, these deposits are to be counted among the Rhenish lignite; organizationally and culturally, however, the lignite mines located in this area belong to the mining districts of the adjacent mountains, which are characterized by other mineral resources.
These include:
Occurrences on the western edge of the Bergisches Land near Bergisch Gladbach and on the northern edge of the Siebengebirge near Troisdorf, Siegburg and Bonn, belong to the ore districts there (see Bensberg ore district). Occurrences on the northern edge of the Eifel near Euskirchen and Zülpich (today Lake Neffel and Lake Zülpich). Deposits in the Dutch and Belgian part of Limburg, between Heerlen and Genk, belong to the Limburg coal district Vorkommen am Westrand of Bergischen Landes at Bergisch Gladbach and at Nordrand des Siebengebirges at Troisdorf, Siegburg and Bonn, are among the Erzrevieren (see Bensberger Erzrevier) Occurrences at the northern edge of Eifel at Euskirchen and Zülpich (today Neffelsee and Zülpicher See) Occurrences in Limburg (Netherlands) and Limburg (Belgium), between Heerlen and Genk, belong to Limburger Steinkohlerevier.
Geology During the Tertiary period, subsidence movements began in the Lower Rhine Bay 30 million years ago. A shallow sedimentation basin was formed for the original rivers Rhine, Rur, Erft, Sieg and Meuse. This basin gradually subsided and formed relay fractures, while the neighboring Rhenish Slate Mountains were uplifted. In several phases the primeval North Sea advanced into this area. Bogs, whose vegetation could not be decomposed in the water, formed above the clay layers deposited in depressions. The resulting low thickness peats were covered with gravels, sands and clays by further alternations of marine transgressions and regressions. Between 20 and 23 million years ago, at the beginning of the Miocene, climatic conditions favored mire vegetation and the formation of peat. Gravel layers were deposited on the peat layers, sealing them airtight, and their pressure intensified the process of coalification: the peat gradually became lignite. In the main seam group of the Ville, lignites of up to 70 meters thickness can be found today. In the last phase of the Miocene, the seams of the Inden strata formed above the Rurscholle in the western district. In the Pliocene, no seams formed, instead the area went into increased tectonic unrest. The basin broke along two main fault lines (Rurrand and Erft line) into three floes, which in turn formed smaller terrain jumps and relay fractures. These northward-roofing floes subsided to varying degrees, tilting eastward. The lignite layers of the Erftscholle are covered with sediments of 100 (Rurrand) to 400 meters (Erftsprung), in northern direction partly even more. The seams strike the surface of the Villehorst in the southern district near Brühl or were cut in the impact slope by the Tertiary Rhine or the streams of the foothills.
History of the lignite industry First uses (17th to 19th centuries)
Initially, lignite was only extracted as a basic material for the color production of the Cologne umber and for the leaching of alum. It was not until the end of the 17th century that it was discovered that the wet, unusable layer, which was stored above the clay layer during clay extraction for the ceramics industry in the Brühl and Frechen area and had to be cleared away, was combustible after drying. The respective landlords then had this peat-like substance (turf) dug in small pits by small farmers and day laborers with hoes and spades. It was compressed in pots to Klütten (from Low German Kluit = lump) and dried in the air in summer. The Klütten had only a low calorific value. They were used locally or sold to poor people in the nearby town. Such pits still existed until the 1920s.
In the western coalfield, lignite was discovered in 1819 while digging wells in the village of Lucherberg near Inden. In 1826, the landowner Karl von Goldstein began mining a 7.5 meter thick seam.
Beginning of the lignite industry (1850-1905) With industrialization and railroad construction (in 1859, the Dombrücke was the first railroad bridge in Cologne to connect the western Rhineland with the Ruhr region), sales declined due to competition from cheap hard coal, reaching a brief low in 1876.
At the beginning of the general upswing after the Franco-Prussian War of 1870–1871, entrepreneurs in Brühl in 1877 (Friedrich Eduard Behrens with the Roddergrube union) and 1878 (Brühl union) and in 1892 Hermann and his son Carl Gruhl with the Gruhlwerk made coal extraction competitive by means of steam-driven dewatering pumps and revolutionized the production of briquettes by means of mechanical presses. Such presses based on Exter's process had been developed in the Central German lignite mining district in 1872 and were now also used in Brühl. Further briquette factories were established in rapid succession. Supraregional railroad lines as well as the local railroads Köln-Frechen-Benzelrather Eisenbahn of 1893, Bergheimer Kreisbahn of 1897/1899 and Hürth-Kalscheuren-Hürth-Knapsack of 1901 connected towns in the Ville, opened up further coal fields or linked mines to the demand areas.
The first briquette factory in the West was built in 1888 by the Maria Theresia zu Herzogenrath trade union. In 1913, the lignite industry AG Zukunft was founded in the western coalfield as a merger of various small unions with the aim of building a lignite-fired power plant. In 1914, the Zukunft open pit mine and the first Weisweiler power plant went into operation.
Mechanization made further progress: In 1895, the first overburden excavator, which had been built for the construction of the Kiel Canal, was used in the Donatus mine near Liblar. The first inclined dredger for coal mining was used at the Brühl Gruhlwerk in 1907 and was given the name "Iron Man". By 1909, there were already four coal excavators in the 29 mines, and in 1913 only three mines had no excavators. Production rose from five million tons in 1905 to 17.4 million tons in 1913, but sales were still difficult compared with traditional hard coal. The mines competed with each other. In 1899, 19 mines joined to form a sales syndicate to sell briquettes as a branded product under the name Union-Brikett with uniform standards.
In 1907, commercial mining began in the northern mining district between Neurath and Garzweiler with the opening up of the Rheingold field, initially still with picks and lorries. A year later, the first scraper excavator was used. Today, the mining fields are combined in the Garzweiler open pit mine.
Start of electricity generation from lignite (1892-1918)