(1) In the traditional process, corn oil is deodorized and then recrystallized, nourished, filtered and dewaxed. Since diatomaceous earth filter aid is added during filtration, it is acidic, which will cause the acid value of the finished oil to increase and affect the quality of the finished oil . And it will make the finished oil have an obvious earthy smell.The new process places the dewaxing section between the decolorization and deodorization sections. The deodorization tower can remove fatty acids, reduce the acid value, and remove the earthy odor in diatomite, effectively controlling the quality of the finished oil.

(2) The traditional process is to add a filter aid of about 0.2% of the oil mass to the deodorized oil . The temperature of the deodorized oil needs to be cooled to 20 °C and kept for 48 hours with stirring. The wax in the oil slowly condenses, and then is used The filter separates the waxes from the oil.The new process is to add a filter aid of about 0.2% of the oil mass into the decolored oil , quickly cool it to 5~10 °C and stir it at a slow speed of 10~13r/min . Under this condition, keep it for 7~8h , and then Use a horizontal filter to remove wax.

Through practical comparison of the two processes, it was found that the dewaxing process in the latter process takes a short time without affecting the quality of the oil, and can increase output, thus improving the economic benefits of the enterprise and reducing investment costs.

Issues that should be paid attention to during production corn oil:

(1) In practice, the degumming section has a greater impact on the quality of the refined oil. If the gum removal effect is not good, the color of the corn refined oil will change seriously. And the high colloid content will affect the stripping effect of the soft tower.

(2) Solid caustic soda with a purity of 99% is used during alkali refining . Because the presence of Ca 2+ and Mg2+ ions also has a greater impact on the color recovery of corn oil products.

(3) Since corn crude oil contains high impurities during the oil extraction and leaching processes, it is recommended to let it sit and settle before degumming and alkali refining to reduce the impurity content in corn oil in order to improve the separation effect of the disc separator. , to control the impurity content in corn crude oil0.2%.

(4) The oil temperature in the soft tower in the deodorization section should not be too high and should be controlled at around 230°C .

(5) After the deodorization section , the corn oil must be cooled before it can be put into the warehouse. The oil temperature in the warehouse should be controlled below 30°C in winter and below 35°C in summer to prevent the color of the corn oil from changing.

(6) In order to increase the yield of corn oil products and reduce production costs, the acid value of alkali refining is controlled at 0.2~ 0.25 mgKOH/g .

(7) In order to increase the filtration rate of the dewaxing section and improve the dewaxing effect, it is recommended to use diatomaceous earth as a filter aid instead of perlite.