Get the high-grade cooking oil from crude oil through the hydration degumming, continuous decoloring, filtering, continuous deacidifying and deodorizing 4 main sections. It’s a flexible process, economic and environmental protective.
Phosphoric acid alkali liquor
Crude oil→preheating→mix→centrifugal separation→degumming oil
Off-acid oil←cooler←dry ←centrifuge separation←chemical reaction
1,The small amount of free fatty acids in the crude oil can result in oil physicochemical stability weaken ,must be made to remove. The deacidified Method has alkali refining, distillation, solvent extraction and esterification. One of the most widely used is the alkali refining and distillation. Distillation deacidification also called physical refining.
2,Alkaline deacidification is adding the alkali, acid, water and other substances to the oil, remove the certain amount of free fatty acid and gum heteroaryl in the crude oil.
3,Alkali refining can be used before the mixed oil evaporation processing, can reduce the saponification of the neutral oil, reducing the oil content of the soapstock also to avoid the leaching plant evaporator fouling, and low energy consumption, refining less consumption, after the alkali,the refining oil has good color, no waste water emissions and no pollution to the air.
bleaching earth →Degummed oil→mix→decoloring→filter→decolored oil
The main function of decoloring process is to remove oil pigment, residual soap grain and metal ions. Under negative pressure, the mechanical mixing method combined with steam mixing will improve the decoloring effect.
The degummed oil firstly enters into the heater to be heated to the appropriate temperature (110°C), and then goes to the bleaching earth mixing tank. The bleaching earth is delivered from the low bleaching box to the temporary tank by wind. The bleaching earth is added by automatic metering and is interlockingly controlled with the oil. The oil mixed with the bleaching earth overflows into the continuous decolorizer, which is stirred by non-powered steam. The decolored oil enters into the two alternate leaf filters to be filtered. Then the filtered oil enters the decolored oil storage tank through the security filter. The decolored oil storage tank is designed as the vacuum tank with the nozzle inside, so as to prevent the decolored oil contacting with the air and influencing its peroxide value and color reversion.
Vacuum steam jet pump←steam
Decolored oil→deodorization tower→cool→deodorized oil→filter→refined oil
The qualified decolored oil enters into the spiral plate heat exchanger to recover most of the heat, and next goes to high pressure steam heat exchanger to be heated to the process temperature (240-260°C) and then enters the deodorization tower. The upper layer of combined deodorization tower is the packing structure which is mainly used to remove the odor producing components such as free fatty acid (FFA); the bottom layer is the plate tower which is mainly for achieving the hot decoloring effect and reducing the peroxide value of the oil to zero. Oil from the deodorization tower enters into the heat exchanger to recover most of the heat and makes further heat exchange with crude oil, and then is cooled to 80-85°C through the cooler. Add the required antioxidant and flavor agent, and then cool the oil below 50°C and store it. Such volatiles as FFA from the deodorizing system are separated by the packing catcher, and the separated liquid is FFA at low temperature (60-75°C). When the liquid level in the temporary tank is too high, the oil will be sent to the FFA storage tank.