Coal piles
A Kohlenmeiler (short- pile ) is a covered timber pile, of one of Köhler is set fire to charcoal to produce. It is also referred to as a square , ring and standing pile , in contrast to the pit pile . Further variants are the platform pile and the slope pile .
history
Charcoal has been made using charcoal piles since ancient times . Charcoal is much lighter than felled wood and therefore easier to transport. In addition, charcoal generates a lot more heat. The charcoal burning was therefore an important branch of the economy in the early modern period . Back then, charcoal was the only fuel that could be used to generate the heat required for smelting iron . In 1788 the article “State and duty provision of a coal master at an ironworks” stated that he had to not only take care of the coal wood supply, supervise coalers and their servants, but also visit the “ Kohlhäue ” more often, i.e. the forest which is used to extract the cabbage wood. In 1713, a process was invented to produce coke suitable for blast furnaces from hard coal . After that, the consumption of the expensive charcoal decreased more and more despite increasing iron production. From the 17th century onwards, pitch ovens were increasingly used, and in the 19th century retorts were also used . As a result, fewer and fewer coal piles were needed. The gradual decline for charcoal began in the 19th century, when hard coal then practically replaced charcoal and later gas and electricity also gained in importance. The Second World War again triggered a strong demand for charcoal. At that time, motor vehicles were also powered by wood or charcoal.
Today it is of no particular economic importance, in particular due to the loss of wood gas during the burning process, the calorific value from the wood is extremely low. The charcoal factory is only operated for reasons of tradition and for some special applications of charcoal.
functionality
In order to produce charcoal, water and the volatile components of the wood must evaporate .
On the Meilerplatz , if possible in a place near a body of water for later extinguishing, the wooden pile is built in approximately hemispherical or conical piles, with large logs , usually one-meter logs, regularly (standing or lying), all around, around the quandel . All around a can Stübbewall be built.
On top of this is an airtight roof made of dry fir branches or with leaves, hay or straw (Knipp-Knüppdach), grass , plant sod and moss (rough roof) together with the green roof and at the end the pile with extinguishers (Stübbe, Stibbe, Gestübe) and Earth (earth roof), with the exception of Quandel, sealed airtight. A support made of round wood and boards is then created around the base of the pile. Then the kiln is ignited via the quandel, then this is also closed.
A sure sign that the charring has started is the so-called knocking of the kiln; the strong warming leads to wood gas deflagration , which can lead to an explosion of the kiln if the kiln cover is too strong . At the top as well as at the foot of the kiln, individual holes, called rooms , places or draw holes in charcoal burning , are pierced with which the fire in the kiln can be regulated. Under this blanket, the incineration is conducted with carefully regulated air access in such a way that, if possible, not more wood burns than is absolutely necessary to heat the entire wood mass to the charring temperature. The wood must not burn in the kiln, but only char, air is let in through the small air holes so that no fire can start. But it creates a lot of heat and the water evaporates, tar condenses on the green roof, the smoke is yellowish-white and odorless . The heat of the smoldering wood inside the kiln then drives all liquid and organic components out of the wood as smoke.
The charcoal burner's job is now to neither go out nor let it burn down due to too much air supply over the following days or weeks (depending on the size of the kiln and the weather). To do this, he drills and closes the draw holes. Essentially, only the gases and vapors evolving from the heated wood should burn. By observing the smoke or its color, the Koehler must recognize whether there is too much or too little air supply. The color of the smoke that escapes indicates whether the charring is complete. If the smoke is white and thick , the wood is not yet charred, it is light , almost transparent and slowly bluish , the wood is charred. The draw holes are now moved further down to draw the fire into the lower areas of the kiln. Each time the draft holes are moved, the smoke color changes, the kiln charred from top to bottom. As the charring progresses, the kiln slowly sinks in.
When the charring is complete, the fire in the kiln is quickly suffocated by the clogging of the air holes and the kiln slowly begins to cool down. The kiln is now called a piece because it is burned out , the process of cooling down is called cooking . For better sealing, the pile ceiling is often sprinkled with water and compacted with a wooden hammer. The pile has now shrunk to about half its original volume. Now the cover is opened and then the coal is pulled out with a rake, a fork or a shovel ( coal pulling , coal length ) and spread out to cool. Embers are extinguished with water or suffocated with extinguisher. If this does not succeed completely, the previously created charcoal burns within a very short time with great heat development ( exothermic reaction ). The resulting heat is so great that it is impossible to get close to the kiln. The coal must now be min. Cool for 12 hours. Coal that is too small remains in the kiln and is mixed with the extinguisher. Around 98% only the carbon structure of the wood cells remains.
Approx. 30 kg of charcoal can be obtained from 100 kg of hardwood .
By-products such as wood tar , wood vinegar , wood spirit and wood gas are produced during the charring process . These cannot be fully utilized in the kiln. Should tar extraction be combined with the coaling of the kilns, small pits were dug in the ground or the ground was lined with clay and the tar was led out of the kiln through a channel, the wood vinegar was conducted into a reservoir with iron or copper pipes or it were pitch oil stones and brick slope reactors built.
Traditions
In various cities such as Selb , Tharandt , or Waldmünchen as well as villages such as Walhausen (Saar) , Hayingen -Münzdorf, Fischbach (near Kaiserslautern) and Glasofen in Spessart there are regular so-called Köhler festivals or Meiler festivals or Meilerwochen. In Switzerland , a coal pile is set up every five years in the Mettauertal in the Aargau Jura Park. In Alsace , a big charcoal burner festival takes place every year on Fleckenstein.
photos
Core (Quandel) of the Meiler on a former Meilerplatz
Layering the beech wood around the core
Pile with different layers (wood, spruce branches, turf)
Ignition of a pile by guests of honor at a pile festival (2014)
Covered with clay, ready to light
Finished kiln with vestibule, charcoal burner hut and fireplace
Coal pile in the WFM Hagen
Coal piles in Walpersdorf, one of the last in the Siegerland
Opening of the coal pile
Charcoal yield
Köhler at work (turn of the 19th / 20th century)
Sectional drawing of a coal pile
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literature
- Karl Hasel , Ekkehard Schwartz : Forest history. A floor plan for study and practice. 2nd updated edition, Kessel, Remagen 2002, ISBN 3-935638-26-4 .
- Richard B. Hilf: The forest. Forests and pastures in the past and present - first part. (Edition Jafona), Humanitas, Wiebelsheim 2003, ISBN 978-3-923-52701-4 (reprint).
- H. Hildebrandt, B. Heuser-Hildebrandt and M. Stumböck: Existing historical and cultural landscape genetic investigations in the natural forest reserve Stelzenbach. Nassau Forestry Office, Winden Revier, Mainz Natural Science Archive, Supplement 25, 83 pages, Mainz 2001, DNB 963501801 .
- Th. Geilenkirchen: Basics of the iron and steel industry: 1st volume, Springer, 1911, ISBN 978-3-642-89738-2 , p. 125 ff.
- Arne Paysen: Sustainable Energy Industry? Dissertation, Faculty of Mathematics and Natural Sciences, Christian-Albrechts-Universität, Kiel 2009, pp. 96–118, online (PDF; 99.2 MB), on macau.uni-kiel.de, accessed on January 16, 2017.
Web links
- European charcoal club .
- Charcoal burning in Entlebuch (Switzerland) UNESCO biosphere cultural heritage .
Individual evidence
- ↑ Grubenmeiler ( Memento from January 9, 2017 in the Internet Archive ).
- ↑ pedestal pile on kraeuterhuegel.at, accessed on 16 January 2017th
- ↑ Forest and hunting library or useful articles, comments and ordinances etc. regarding the entire economic forest, hunting, wood and floss being as a continuation of the general forest magazine. First piece, by Johann Bendikt Mezler, Stuttgart 1788, p. 36, limited preview in the Google book search.
- ↑ a b Der Kohlenmeiler ( Memento of the original from May 9, 2016 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 1.25 MB), at 750jahrewolfwil.ch, accessed on August 14, 2016.
- ↑ Gustav Fester: The development of chemical technology. M. Sendet (Ed.), Wiesbaden 1969, ISBN 978-3-642-89671-2 (reprint), p. 188.
- ↑ Dieter Osteroth: Biomass: Return to the ecological balance. Springer, 1992, ISBN 978-3-642-77410-2 , p. 88.
- ↑ Meiler Festival in Selb .
- ↑ Green League: Nature Guide Eastern Ore Mountains .
- ↑ Coal piles in Waldmünchen .
- ↑ Coal pile time in Waldmünchen .
- ↑ Koehler Days in Walhausen .
- ↑ Koehler Festival Fischbach .
- ↑ Köhlerverein Glasofen im Spessart ( Memento of the original from March 22, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. .
- ↑ Mettauertal charcoal factory .
- ^ Les Charbonniers du Fleckenstein .
