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Z. Xiao et al.
2.3 Mechanical Crushing Method and Process
Crushing method is an effective way to get oil from the fruit, with the aid of the
role of external mechanical forces. Now crushing method is the main method of oil
extraction plant in China. Crushing method is adaptable, simple operation process,
production equipment maintenance convenient, flexible production scale, product
quality good, light color, good flavor, suitable for all kinds of vegetable oil extraction,
safe production at the same time, but crushing method is residual oil high in press
cake, low efficiency, large power consumption, parts easy to wear and tear.
Now the crushing equipment mainly includes two categories: intermittent production of hydraulic press and continuous production of spiral press. Hydraulic press
is according to the theory of fluid transmitting pressure, the fruit in the cake circle is squeezed, and the oil is out of the fruit. The crushing machine has a simple
structure, convenient operation, low power consumption, and oil cake with good
quality. It can process a variety of fruits, but is only suitable for mall scale processing. But hydraulic press process is the labor strength, strict process conditions, has
been gradually replaced by continuous squeezing device. Screw press was widely
used in the world’s more advanced continuous oil equipments. Its working principle
is with continuously forward, at the same time due to the squeeze of spiral lead to
shorten or root diameter increases, the pressing chamber space is shrinking volume
and pressure, and the billet material is pressed into bread pieces, oil flows out from
a crack in the press cage.
In the pressing process, the seed is subjected to extreme heat and pressure with oil
mechanically forced from the oil cell. A typical pressing operation involves cooking,
pressing, cake cooling and finishing, and oil filtration. The operation and configuration of extraction in different plants is different. In a generic operation, pressed meats
from the flakes enter a cooker where heat is applied and protein is denatured. After
the cooker, the hot meats enter a mechanical press, where about 60% of the available
oil is removed by the application of intensive mechanical pressure. Using a full press
operation, the oil exits through drainage bars during the process of pressing, there
is about 90% of the available oil. Because the raw material is cooked, compressed,
passed through the end plate, where through the application of high friction, so that
the cake is often quite hard. After the pressing operation, the cake is normally broken
and cooled, with the prepressed cake usually sent to the solvent extraction unit for
final oil removal. If the economics do not permit solvent extraction, a higher degree
of oil removal is performed. This is also known as a full press operation. And the
cake can be used directly as animal feed after removing the harmful substances.
Z. Xiao et al.
2.3 Mechanical Crushing Method and Process
Crushing method is an effective way to get oil from the fruit, with the aid of the
role of external mechanical forces. Now crushing method is the main method of oil
extraction plant in China. Crushing method is adaptable, simple operation process,
production equipment maintenance convenient, flexible production scale, product
quality good, light color, good flavor, suitable for all kinds of vegetable oil extraction,
safe production at the same time, but crushing method is residual oil high in press
cake, low efficiency, large power consumption, parts easy to wear and tear.
Now the crushing equipment mainly includes two categories: intermittent production of hydraulic press and continuous production of spiral press. Hydraulic press
is according to the theory of fluid transmitting pressure, the fruit in the cake circle is squeezed, and the oil is out of the fruit. The crushing machine has a simple
structure, convenient operation, low power consumption, and oil cake with good
quality. It can process a variety of fruits, but is only suitable for mall scale processing. But hydraulic press process is the labor strength, strict process conditions, has
been gradually replaced by continuous squeezing device. Screw press was widely
used in the world’s more advanced continuous oil equipments. Its working principle
is with continuously forward, at the same time due to the squeeze of spiral lead to
shorten or root diameter increases, the pressing chamber space is shrinking volume
and pressure, and the billet material is pressed into bread pieces, oil flows out from
a crack in the press cage.
In the pressing process, the seed is subjected to extreme heat and pressure with oil
mechanically forced from the oil cell. A typical pressing operation involves cooking,
pressing, cake cooling and finishing, and oil filtration. The operation and configuration of extraction in different plants is different. In a generic operation, pressed meats
from the flakes enter a cooker where heat is applied and protein is denatured. After
the cooker, the hot meats enter a mechanical press, where about 60% of the available
oil is removed by the application of intensive mechanical pressure. Using a full press
operation, the oil exits through drainage bars during the process of pressing, there
is about 90% of the available oil. Because the raw material is cooked, compressed,
passed through the end plate, where through the application of high friction, so that
the cake is often quite hard. After the pressing operation, the cake is normally broken
and cooled, with the prepressed cake usually sent to the solvent extraction unit for
final oil removal. If the economics do not permit solvent extraction, a higher degree
of oil removal is performed. This is also known as a full press operation. And the
cake can be used directly as animal feed after removing the harmful substances.