How to extract oil from oil plants (Expeller pressed method)
Rapeseed oil extraction
when the rape seed are cooked in the roaster and it blow out a cloud of light smoke, lower the heat and remove rape seed from the roaster until it is grinded and has deep yellow color. Then lower the temperature at 60°C and feed them into the oil press to pressing, the exceeding oil has yellow color and the cakes are present as black and yellow sheet and long strip.
Problems which are easy to present during rape seed pressing
1). Too much residue without enough oil output: the reason is that lowering the temperature is inadequate after cooked the rape seeds.
2). Lower speed of filtering: the main reason is that there are too many impurities and much soil during the pressing process with the lower temperature of each part of oil press. At this time, open the heating of oil pan and use the other two filters in turn, clean up the residues on the filter cloth timely, clean or replace of the filter cloth.
3). The vacuum pump has oil injection: due to the long time of filtering, the vacuum gauge has reached to limit (-0.1). Oil foam keeps rising from the wind notice. If it continues to filter, oil will be feed into the vacuum bag. Then the oil is absorbed into the vacuum filter and blowout from the vent holes, which lead to reduce the ratio of oil output. Under this situation, stop the vacuum filter for a second and continue to operate the oil press machine until the vacuum gage lower at -0.09.
Peanut oil extraction:
Warm the oil press at about 180°C, put the peanut into the roaster and press oil until the peanut has light yellow color with hotness. The exceeding oils are white yellow in color and the cakes are big sheet or long strip.
Problems which are easy to present for peanut pressing:
1). Returning of oil: (oils are flowing out from the bottom) the primary reason is that the oil grooves are blocked. We can knock the bar of pressing cage with iron rod and dredge the oil grooves; in addition, a little water should be added into the boiler during cooking, which make the cooked peanuts has elasticity, to avoid of blocking.
2). crushing of cakes: the main reason is lower temperature of the cooked peanuts. Increase the temperature of peanuts when it is going to cooked and put the cooked peanuts into the oil press timely.
3).Oil injection of vacuum pump (same with rape seed)
Soybean oil extraction:
Soybeans belong to low oil content plant and the oil content of soybean is about 11-20%. Screen and remove of impurities by screen with 12 meshes before pressing, to improve the oil output of soybean.
Problems which are easy to present during soybean pressing
1). Running of residues: small amount of running residues belong to normal phenomenon. If the running residues are beyond 5%, it is necessary to adjust the soybean oil press. In the light of oil plant, too high or low of moisture content caused the running residues. If the oil plant has high moisture content, the residues are like strips from the sheet row. And the cakes are soft with grasping into clusters and the flowing oil has white foam. If the moisture content is lower, the residues are powdery from the sheet row.
2). Returning of oil: for soybean pressing, there is little of returning of oil. This phenomenon happens during pressing of high oil content plants. Adjustment of the sheet row and loosen the compressing nut, to increase the gap of round row.
Sesame oil extraction:
Put the sesame into the boiler. The sesame is expanded and spread with yellow color, and the oil squeezed form it. Elevate the sesame for several times and put into the oil press after removing of black smoke. The oil has red yellow color and the cakes are big block or long strip.
Problems which are easy to present during sesame pressing
1). Cakes are in pieces, crushing of cakes, running residues and splashing oils: the reason is that sesame is not fully cooked; the other reason is due to the low temperature during the eliminating of smoke.
2). Cakes are twining round the screw and they are in round lump shape. The residues are like noodles that come out from the pressing cage and the oil is black with heavy smoke from the oil press. And the oil taste bitter with lower feeding speed, the reason is that the sesame is cooked beyond the limit or the temperature of pressing is too high. In addition, too tightness of the screws can cause the same kind of problems.
Small oil pressing plant
The small oil pressing plant is a mini capacity oil extraction line which is fully adopted mechanical driven. It connects a series single oil processing equipment together to realize continuous oil extraction with easier operation and higher rate of oil yield for a greater efficiency. The small plant is able to process a great number of oil plants, such as peanuts, rapeseeds, sunflower seeds, soybeans etc.