Damme iron ore mine
| Damme iron ore mine | |||
|---|---|---|---|
| General information about the mine | |||
| Mining technology | Underground mining | ||
| Funding / year | up to 950,000 t | ||
| Funding / total | 9,200,000 t | ||
| Information about the mining company | |||
| Operating company | Ore mining at Porta Damme | ||
| Employees | up to 919 (1961) | ||
| Start of operation | 1939 | ||
| End of operation | 1967 | ||
| Funded raw materials | |||
| Degradation of | Iron ore | ||
| Greatest depth | Shaft 1: 282.3 m
Shaft 2: 205 m |
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| Geographical location | |||
| Coordinates | 52 ° 32 '46 " N , 8 ° 11' 9" E | ||
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| Location | Wempenmoor | ||
| local community | Dams | ||
| District ( NUTS3 ) | Vechta | ||
| country | State of Lower Saxony | ||
| Country | Germany | ||
The Damme iron ore mine in Damme existed from 1939 to 1967 and was operated by Erzbergbau Porta-Damme AG from 1952 .
The deposit
The iron ore reserves occurring in Südoldenburg are secondary deposits . The clay-iron stone grounds stored in the Lower Cretaceous are the size of a fist or over the head. They contain various clay minerals , silica , calcium carbonate and some have an iron content of over 30%.
The geodes , which were exposed to weathering over time , ended up in the surf area of the sea at the end of the Upper Cretaceous Period . There the geodes were crushed and rounded to the size of a walnut or a pinhead. These geodes deposited in the mud. In the course of time, the iron ore deposit was covered by younger sediments . Today this deposit is called Dammer Oberkreidemulde. It has an extension of 35 km in an east-west strike direction and 10 km in a north-south direction. Several iron ore deposits were formed in this hollow . The iron ore deposit in Damme has a spread of 25 km in an east-west direction and 1.5 km in a north-south direction. Other unworthy ore deposits can be found in Gehrde and Rieste . The depth of the deposit varies from 150 m in the east to 280 m in the west. From this it can be deduced that the iron ore-containing layers dip by 5 to 7 °. The thickness of the ore deposit is greatest at 8 m in the north. The continuous thickness is 1.5 to 3 m. The composition of the ore is: 25-35% by weight iron , 8-15% by weight calcium oxide , 15-20% by weight silicon dioxide , 0.5-1% di phosphorus pentoxide , 0.1-0.2% Manganese oxide , 4-6% alumina and 1-2% magnesia . The processed ore concentrate contained 42-45% iron. The iron ore deposit near Rieste was unworthy of construction with an iron content of 20%. The mineable reserves are estimated at 90 million tons, of which 9.3 million tons were extracted as raw ore.
Exploring the deposit
Boreholes by the Grand Duchy of Oldenburg to find minerals that could be mined, which were sunk from 1909 to 1912, came across the iron ore deposit. Further drilling was carried out from 1918 to 1925. The drilling was only continued in 1937 when the Third Reich was striving for self-sufficiency. When the ore deposit appeared sufficient in 1939, the decision was made to build a test facility.
history
On February 1, 1939, the mining trade union Damme was founded. Their Kuxe were distributed among the following companies: 52% Vereinigte Stahlwerke , 19% Krupp , 12% Hoesch , 10% Klöckner and 7% Mannesmann . Krupp AG took over management of the company. A 282 m deep shaft was sunk 3 km north of Damme . The diameter was 5.2 m. The upper 190 m were sunk using the freezing process due to the heavily water-bearing gravel layers. The shaft was equipped with a weather sheath. 1942 with the decomposition of the deposit started. The poor ventilation of the mine stood in the way of a generous development, and the shortage of skilled workers due to the war also made itself felt. At times up to 300 prisoners of war were employed in the pit. First small quantities of ore promoted to 1944 revealed . When the war ended, ore mining was over. 25 people were left with jobs to maintain the mine. The declining German steel industry would not have been able to purchase any ores either.
post war period
In April 1946, the Allied Control Authority released production again. The pros and alignment of 260 m sole was further advanced. From 1948 onwards, one shift was carried out every day , ore mining was started and test processing started. In this first year, 18,792 t of raw ore were mined. Extensive mining tests were carried out until 1952 to determine the most favorable for this deposit. In 1952, 166,282 tons were already being mined with a workforce of 248. At the same time, Erzbergbau Porta-Damme AG was founded in 1952 as a subsidiary of Barbara Erzbergbau AG and Harz-Lahn Erzbergbau AG, each with a 50% share. Further financial resources have now been made available to expand the company to 3,000 tonnes per day. The most important undertaking was the deepening of shaft 2 to 269 m using the Honigmann shaft drilling method in 1953/54.
Deepening the shaft 2
The starting point of the shaft is 144 m northeast of the first. Since it was already known from the first shaft that 174 m of unstable water-bearing diluvial layer sequences were to be expected, the freezing or Honigmann shaft drilling method had to be used here as well. To save time and money, the Honigmann shaft drilling method was used. This process was invented by the mine owner Honigmann from Aachen and had already been tested in Aachen and the Netherlands. The West Rhine deep drilling and shaft construction company received the order to carry out this. The method is based on several drilling stages and thick mud . After reaching the required depth of 22 m, drilling was started in the foreshaft. In January 1954 the first step with a diameter of 2 m was completed. The 3.5 m and 5.1 m steps followed. After expansion of the shaft wall, which consisted of double-walled U-irons with intermediate concrete was cement and concrete broth behind the ring expansion passed. This shaft ended on the solid rock at a depth of 189.30 m. The rest up to the 260 m level was sunk by hand. This was completed in 1955. The 205 m midsole was connected to shaft 1 and weather openings were created.
Expansion and decline of the colliery
With the completion of shaft 2, a larger workforce could be built up for the first time. Production could also be increased. In 1956, 559,667 tons were extracted by 749 men. Already at depths of shaft 2, one proceeded to the backbone to give of the shaft 1 made of wood of a steel. The scaffolding was designed as a double gantry, the hoisting machine had an output of 520 kW. The brick buildings, which are still largely preserved, were built by 1958. The raw ore, which had 30% iron, was broken down to an initial 200 mm using crushers . A second time to 40 mm and a third time to 10 mm. In upflow the ore was enriched. To process the ore, 3.6 m³ of water per ton of ore was required, for daily water consumption 6,600 m³ of return water from the clarification ponds, 3,000 m³ of mine water and 2,400 m³ of fresh water from deep wells were required. In 1960, 913,946 t of ore were mined by 960 men, which resulted in 480,296 t of ore concentrate. The crisis in German iron ore mining was soon announced. The subsidy had to be drastically reduced, the wage and material costs rose faster than the sales price. In particular, the competition with higher quality, foreign ore, which was not more expensive than German ore despite freight costs, put the mine in trouble. An attempt was made to save the mine with a better preparation to 47% iron in concentrate in 1962. The mining was also limited to particularly promising ore fields with over 30% iron. The production could be increased to about 5.5 t per man and shift (1952 = 2.2 t). But all expenses could not prevent the shutdown on March 31, 1967.
Mine disaster
On January 17, 1963 arrived in the pit depth of 200 meters at a distance burglary , were buried at the five-mate.
today
Establishments
After the closure in 1967, there were many wood and furniture companies on the former colliery site. The Dammer Möbelwerke were located in the buildings of the shaft system until the summer of 2006. The former colliery site was expanded, however, and Zerhusen Kartonagen GmbH and Dammer Logistik were housed in the rear halls. The site has been owned by Paul Schockemöhle Logistics GmbH, to which DL Dammer Logistik belongs, since 2007. After the mine was closed, many miners found new employment in the Grimme agricultural machinery factory located in Damme .
building
Most of the mine’s buildings are still partially well preserved today, such as the headframe of shaft 2, the mooring, the operations building and the halls. The other buildings have been partially torn down or have fallen into disrepair, such as the laundry and the concentrate bunker. There are still two tunnels under the site today . Once the crew corridor, in which the miners could go from the Kaue to shaft 1. This corridor is still complete and in good condition, but it was walled up shortly before the hanging bench of shaft 1. The other tunnel is the central channel, in which many pipelines run from the washing machine to the elevated tank. This tunnel has also been completely preserved and has been set up so that bats can hibernate.
Exhibition & guided tours
At the end of March 2012 the exhibition on ore mining in Damme was opened in the building of the former Kaue, which was brought to life by Paul Schockemöhle Logistics Damme GmbH in cooperation with the Tourist-Information Erholungsgebiet Dammer Berge eV. In the exhibition are u. a. Pictures and a film of the work underground can be seen. The exhibition is combined with a guided tour through the former company premises. In the meantime, the tour guide explains to the visitor in detail the stations of the tour (including the underground crew passage, chew) and the history of the Damme iron ore mine.
literature
- I. Eichfeld: Industrial history in the recreation area: traces of former ore mining in the Dammer mountains . In: A. Bauerochse, H. Haßmann, U. Ickerodt (eds.), Cultural landscape, administrative - digital - tourist. Environmental protection initiatives 67. Erich Schmidt Verlag, Berlin 2007, 391–404. ISBN 978-3-503-09794-4 .
- Hans Röhrs : ore and coal. Mining and ironworks between Ems and Weser . Ibbenbürener Vereinsdruckerei (IVD), Ibbenbüren 1992, 263 pages, ISBN 3-921290-62-7 .
- F. Hamm : Natural History Chronicle of Northwest Germany . Landbuchverlag, Hannover 1976, 370 pp., ISBN 3-7842-0124-5 .