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be characteristic of fresh oil without foreign smell, aftertaste and bitterness.
Deodorized oil must be odorless. In the second grade sunflower oil, a slightly musty
smell and a slight bitterness are allowed [2].
Formulation of the problem.
Oil from oilseeds is extracted in two main
ways: 1. mechanical, which is based on pressing of crushed raw materials; used in
oil mills or churns of agricultural enterprises; a by-product is cake, in which a
significant amount of oil remains (8-10%); 2. chemical (extraction), in which
specially prepared oilseed raw materials are treated with organic solvents; used in
oil extraction plants; allows you to release oil in large quantities, as in the waste,
called meal, remains no more than 1-3% of oil [3].
The mechanical method of obtaining oil by pressing the oil-bearing material,
which has undergone preliminary preparation, is widespread almost everywhere not
only at press oil factories, but also at oil extraction plants, where the main
technological scheme is prepressing - extraction. Use only a continuous method of
pressing on screw presses. A distinction is made between screw presses for
preliminary oil removal (forpress) and for final oil removal (expellers). The end
products of the pressing process are press oil and cake. When the auger shaft rotates,
placed in a zeerny cylinder, that is, in a drum assembled from strips with small gaps
between them, the material is transported from the loading point to the outlet and is
compressed. At the same time, pressure arises in it, which squeezes the oil out of the
pulp. The oil flows through the gaps in the bore cylinder and collects in the sump.
The squeezed oil material (cake) at the exit from the grain cylinder meets with a
device that regulates its thickness at the exit from the press. The oil content in the
cake is 6 ... 7%. In this case, the temperature of the material entering the press should
be 110 ... 115 ° С, and the humidity should be 3 ... 4%. Solvents used for the
extraction of vegetable oils by the extraction method must meet the requirements
imposed on them by the technique and technology of the extraction process [4]. In
general, these requirements are determined by the desire to obtain the highest oil
yield during extraction, to ensure the best quality indicators of the finished product
- oil and meal, to avoid the harmful effects of the solvent on the human body and to
ensure the safety of working with it. In the practice of extraction of vegetable oils,
the most widespread are aliphatic hydrocarbons, in particular, extraction gasolines,
hexane, nefras (table 1.). The shape of the material particles in the form of a petal (a
plate of material with a thickness of about 0.4 mm) makes it possible to have a mass
of material that is easily permeable to a solvent in the extractors. From under the
crimping rollers, the conveyors send the petal to the extractor - the main apparatus
of the extraction shop, designed to extract oil into the solvent during countercurrent
contact. Gasoline with a boiling point of 65 ... 68 ° C is used as an extraction solvent.
In continuously operating auger extractors, a countercurrent of petals and a solvent
heated to a temperature of 50 ... 55 ° C is created. The resulting solution is called
miscella, which, after extraction, is filtered on special filters and poured into miscella
collectors. To separate the oil from the solvent, the miscella is directed first in the
preliminary and then in the final distiller, where it is treated with hot steam using
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