Oil mill
An oil mill is the production facility for the production of vegetable oil from seeds and fruits. Among commodities, a distinction is made between oil plants in which the pulp is used (eg, olive, oil palm ) oil and fruit in which the seeds are used (soya, sunflower, rape). Oil mills process the raw materials into oils and greases and oil crushing ( press cake ). Used vegetable oils as food and feed as well as in the technical area ( oleochemicals, biofuels).
Centralized and decentralized oil mills
Vegetable oils are obtained by the pressing of parts of plants. Produces the vegetable oil in a centralized or decentralized oil mills. Central oil mills process up to 4,000 tons of oil seeds per day method of hot pressing and possibly a subsequent extraction. The oil yield of the industrial working equipment is high. The daily processing capacity of decentralized oil mills, however, is between 0.5 to 25 t oilseed. The seed is cold pressed ( cold pressing ) and causes both virgin vegetable oil. The oil yield of working usually in the agricultural environment facilities is low, at higher residual fat content in the press cake.
Method
The production processes of centralized and decentralized oil extraction differ significantly. However, central element in both is the pressure ( screw press or screw press Seiherstab ). Another method for the production of vegetable oil are:
In this method, mucins are extracted, and the vegetable oil with a solvent ( hexane) from the plant cells removed. The " miscella " said mixture of hexane, water, and oil is separated in the distillation into three tiers. The oil is processed so that it can be further processed as a vegetable oil. The recovered hexane is used for further extraction processes.
Particularly in the production of olive oil, a centrifugation is employed. The offset may with water and heated slurry is centrifuged, at about 20 000 revolutions per minute.
Raw materials
The raw seeds or the pulp of plants are used. Worldwide, there are many thousands of oil plants that could be used as raw material suppliers. From oil mills in Europe mainly oilseed rape, soybean, sunflower, corn and cotton are quantitatively processed, along with, among others, olives, various nuts, safflower and grape seeds. Worldwide addition, the oil palm for the production of palm oil and palm kernel oil and coconut palm ( coconut oil ) are of great importance.
Economic Importance
In Germany there are about 20 central oil mills, for the efficient supply of raw materials usually located on large waterways and integrated into national or international corporations. Supply and demand ( pricing) are usually traded on the Commodity Exchange in Chicago. There are also about 600 smaller, decentralized oil mills that operate regional cycles mostly in the agricultural environment.
The central oil mills process in addition to domestic products and imported crops, especially soybean seed. For the decentralized oil mills in addition to the marketing of the vegetable oil is also marketing the coproduct press cake of economic importance. Feature in decentralized oil mills here are the short transport routes for the seeds and the finished products. Due to the variety and diversity of oil mills a continuous supply of vegetable oil is guaranteed.
The majority of production in both centralized and decentralized systems currently used in fuel production. In addition, edible oils and animal oils and lubricants and release agents are produced. For products manufactured from central oil mills is usually to fully refined vegetable oils, while in decentralized plants by gentle oilseed processing so-called cold -pressed vegetable oils are made that are not undergoing refining steps.
History
As food vegetable oil has a very long history. The method to squeeze out vegetable oil from the seeds and fruits, have originated in this context. In the 19th century, Germany had 4,000 oil mills. With the beginning of industrialization in the last century and a centralization began in this area. Since the beginning of the 90s of the last century there has been revival of the decentralization of the oil mills.
At least ten of the major oil mills are subsidiaries of international companies such as Bunge Limited, Cargill and Archer Daniels Midland. More than half of the decentralized oil mills are located in Southern Germany, especially in Bavaria.
Historic mills
The oil mill Berschweiler and the fire Höfer mill at Gschwend are historic mills that are no longer in operation, with an original technique, however, is completely preserved. Various oil mills are found in open-air museums, such as the Vogt Farm ( Black Forest ) in Fürth in Ostertal (oil mill Wern ) and Roscheider yard ( Upper Moselle ). The Herzsche oil mill in Wittenberg on the Elbe, founded in 1823 and 1856 added to the memory, now forms the backdrop of the Elbe Festival Wittenberg.
Since 1923, the listed oil mill of the vinegar and mustard factory Ph. Leman GmbH is operating continuously. Previously, especially beechnuts were pressed here with mustard seeds and rapeseed.