About Oil Mill Machines
Technique of Oil Mill Machine
A grinding mill is an oil mill where the oil bearing seeds are bruised or crushed for extracting oil and the machines which are used in the oil mill are Oil Mill Machines. The machines which are used in an oil mill include the expeller press, dewatering screw press, belt filter, filter press etc.
The seeds which are used for oil extraction include the peanuts or linseed, olives etc. The expeller press machine is used for extraction of oil from these seeds and after extraction the remaining solid material is used as bio fuel or fertilizer or as a food.
Oil pressing or expeller pressing machine uses the process of extraction of oil from seeds or raw materials. Under high pressure the raw materials in a single step are squeezed. The typical raw materials like seeds, nuts and algae are used for extraction of food oils which are supplied in a continuous feed to the press machine.
The friction heats up the raw materials when pressed. Higher pressures are required for the harder nuts and the materials on pressing can exceed the level of temperatures to 49 degrees Centigrade or 120 degrees Fahrenheit.
A screw type machine is an expeller press which through a cavity like caged barrel presses the oil seeds. One side is used for entering the raw materials and the other side is used for the exit of the waste products. The machine uses continuous pressure and friction from the screw drives to compress and move the seed materials.
There are small openings through which the oil seeps and it does not allow the solids of the seed fibers to pass through the openings. The pressed seeds later are formed into cake like hardened structure which later from the machine is removed. The heat in the range of 60 to 99 degree Centigrade or 140 to 210 degree Fahrenheit is created by the pressure involved in the expeller press machine. Some mills use an apparatus for cooling or reducing the extreme temperatures which is effective in protecting some features of the extracted oil.
The expeller processing is unable to eliminate from the raw material the last trace of oil or liquid. The cake consists of significant amount of leftover oil after pressing. The cake in rural situations or in small scale industries has no importance and so finds significance in manufacturing of secondary products, in preparation of local dishes or for animal feed. By simple expelling, some raw materials do not discharge oil like the most common is rice bran. The commodities which provide no response to expelling the oil from these commodities are removed or final traces are extracted by the process of solvent extraction.
The expeller pressing machine consists of three essential designs which include the resistor teeth, interrupted screw and continuous screw. A continuous screw design was used by the former expeller pressing machines.
The compression screws were similar to the screws used in screw conveyor. In interrupted screw design, interruptions were in the compression screw fighting which was similar to screw conveyor consisting of a hanger. This resulted in consistent press cake and better dewatering. In resistor teeth design, the gap is fitted with these teeth which increases agitation and diminishes tendencies of co rotation.