The Crude Oil temporarily stored in Crude Oil Tank is pumped
into neutralizing tank by Oil Pump. The oil is mixed with alkali
lye in Mixer and neutralized in Neutralizing Tank, free fatty
acid has been neutralized or saponified to be Soapstock.
Physical refining: Physical Refining means
removing gum in the oil in process of degumming in special method
and removing the FFA in process of deodorizing by steam. It
has the following features:
1. Less oil loss and high oil refining ratio;
2. No waste water in process of production;
3. More FFA is distilled out;
4. More suitable for oil with high acid value and low gum-impurity.
Chemical Refining: Chemical Refining means
removing FFA in a chemical way (acid-base neutralization). Gum
and soapfoot is separated out by centrifuges. Chemical refining
has following features:
1. Fine Adaptability and less requirement to crude oil quality;
2. Consistent product oil is got;
3. Less clay is added into compared with physical refining.
Oil Refining process can remove phospholipid, FFA, pigment,
off-flavor and other impurities. It includes the following
sections: Oil Dugumming, Oil Deacidifying, Oil Bleaching, Oil Deodorizing
and Oil Dewaxing.
Oil Bleaching: High-activity clay is added into
oil, mix and heat mixture of oil and clay to make the small
particle of pigment absorbed on the crystal of clay. At last
filtering the oil, perfect mechanism, liable performance, well
Most heat of bleached oil is recovered by heat exchangers, the
bleached oil is heated to the process temperature by mineral
oil or high pressure steam and then the oil enters into the
combined deodorizer, the deodorizer is a combined type: the
upper is packing structure, which is used to remove odor components
like FFA, the lower is plate type used for heat bleaching and
making product quality more consistent. Oil coming from the
deodorizer is cooled and stored after series of heat exchange,
volatile like FFA is collected and stored as by products.
It can improve oil palatability, so it plays an important
role to the quality of finished oil. At the same time, dewaxing
can improve oil transparency and brightness. At present, winterizing
method is very popular to dewaxing.