Production methods and characteristics of oil extraction
I The production method of solvent extraction
The concept of oil production by solvent extraction:The oil production by solvent extraction method is based on the principle of extraction.It is a Kind of oil production methods that An organic solvent that can dissolve grease is selected and brought into contact with the pretreated oil-soaking or spraying, so that the grease in the oil is dissolved. In this way, the solvent and the grease it dissolves form a solution, which is called a mixed oil. Using the different boiling points of the selected solvent and grease, the mixed oil is evaporated and stripped, the solvent is evaporated, and the grease is left to obtain crude oil. The vaporized solvent vapor is recovered by condensation, and then recycled.
II The characteristics of oil extraction
Advantages
The solvent extraction method is an advanced oil press method recognized in the world. In summary, it has the following advantages:
1. When making oil by low-pressure pressing of meal residual oil, the pretreatment process cannot completely destroy the oil cells, and the protein denaturation cannot be very thorough; the barrel temperature cannot be very high, and the barrel pressure cannot be very high. Therefore, the pressing method cannot squeeze the oil clean, and the residual oil rate of the pressed cake is still relatively high.For example, the cakes obtained by the YZX-200 type oil press squeezing a variety of oils have a residual oil rate of 5%-8%.In contrast, using the oil extraction, whether it is direct extraction or pre-press extraction, the residual oil rate of the extracted meal can be controlled below 1%.
2. The quality of meal is better Compared with oil production by pressing method, in the production of oil extraction method, the operating temperature of related processes is relatively low, so that the degree of protein denaturation in solid materials is less, and the quality of meal is correspondingly better. This is very beneficial to the feed value of meal or the extraction of vegetable protein from meal.
3. The production cost is low Compared with the pressing method, the production line used in the solvent extraction method is generally more complete, with a higher degree of mechanization, and easy to realize production automation. Secondly, the solvent extraction workshop has fewer operators and low labor intensity. Furthermore, the energy consumption of the solvent extraction process for oil production is correspondingly lower. Therefore, the production cost of solvent extraction oil is lower.
III Existing problems
1. The possible harm caused by the use of solvents
At the present stage,the solvents used in the solvent extraction method are mainly hydrocarbon compounds. The light gasoline used in the current domestic leaching process uses hexane as the main component. Such solvents are flammable and explosive, and have a strong stimulating effect on the human nervous system. For example, when the vapor concentration of light gasoline in the air reaches 1.20%-7.50%, it will explode when it encounters a fire; when its concentration reaches 30-40mg/l, it will be fatal when it comes into direct contact with people. Regarding these shortcomings of solvents, as long as we strictly implement the "Fire Safety Code for Extraction Oil Plants", strictly abide by the operating procedures, and maintain a high degree of vigilance, accidents will generally not occur.
2. The quality of solvent extracted crude oil is slightly poor
The organic solvent has a strong dissolving power. It can not only dissolve oils, but also dissolve some pigments and lipids in the oils, and mix them in the oils, making the oils darker in color and increasing impurities. In this way, the quality of the solvent extracted crude oil is worse than that of the pressed crude oil, and the refining rate is lower. At the same time, the workload of the refining process will increase accordingly.
3. Increase in investment
Since the solvent used in the solvent extraction production process is flammable and explosive, and harmful to humans, the fire hazard category of the production workshop building should be Class A, and the minimum fire resistance rating should be Class II. The workshop equipment must be grounded, the electrical appliances used must be explosion-proof, and the workshop must be equipped with lightning protection devices. In addition, the equipment and pipelines in the workshop need to be strictly sealed, etc. In this way, the construction of the entire solvent extraction workshop will increase the total investment.
The concept of oil production by solvent extraction:The oil production by solvent extraction method is based on the principle of extraction.It is a Kind of oil production methods that An organic solvent that can dissolve grease is selected and brought into contact with the pretreated oil-soaking or spraying, so that the grease in the oil is dissolved. In this way, the solvent and the grease it dissolves form a solution, which is called a mixed oil. Using the different boiling points of the selected solvent and grease, the mixed oil is evaporated and stripped, the solvent is evaporated, and the grease is left to obtain crude oil. The vaporized solvent vapor is recovered by condensation, and then recycled.
II The characteristics of oil extraction
Advantages
The solvent extraction method is an advanced oil press method recognized in the world. In summary, it has the following advantages:
1. When making oil by low-pressure pressing of meal residual oil, the pretreatment process cannot completely destroy the oil cells, and the protein denaturation cannot be very thorough; the barrel temperature cannot be very high, and the barrel pressure cannot be very high. Therefore, the pressing method cannot squeeze the oil clean, and the residual oil rate of the pressed cake is still relatively high.For example, the cakes obtained by the YZX-200 type oil press squeezing a variety of oils have a residual oil rate of 5%-8%.In contrast, using the oil extraction, whether it is direct extraction or pre-press extraction, the residual oil rate of the extracted meal can be controlled below 1%.
2. The quality of meal is better Compared with oil production by pressing method, in the production of oil extraction method, the operating temperature of related processes is relatively low, so that the degree of protein denaturation in solid materials is less, and the quality of meal is correspondingly better. This is very beneficial to the feed value of meal or the extraction of vegetable protein from meal.
3. The production cost is low Compared with the pressing method, the production line used in the solvent extraction method is generally more complete, with a higher degree of mechanization, and easy to realize production automation. Secondly, the solvent extraction workshop has fewer operators and low labor intensity. Furthermore, the energy consumption of the solvent extraction process for oil production is correspondingly lower. Therefore, the production cost of solvent extraction oil is lower.
III Existing problems
1. The possible harm caused by the use of solvents
At the present stage,the solvents used in the solvent extraction method are mainly hydrocarbon compounds. The light gasoline used in the current domestic leaching process uses hexane as the main component. Such solvents are flammable and explosive, and have a strong stimulating effect on the human nervous system. For example, when the vapor concentration of light gasoline in the air reaches 1.20%-7.50%, it will explode when it encounters a fire; when its concentration reaches 30-40mg/l, it will be fatal when it comes into direct contact with people. Regarding these shortcomings of solvents, as long as we strictly implement the "Fire Safety Code for Extraction Oil Plants", strictly abide by the operating procedures, and maintain a high degree of vigilance, accidents will generally not occur.
2. The quality of solvent extracted crude oil is slightly poor
The organic solvent has a strong dissolving power. It can not only dissolve oils, but also dissolve some pigments and lipids in the oils, and mix them in the oils, making the oils darker in color and increasing impurities. In this way, the quality of the solvent extracted crude oil is worse than that of the pressed crude oil, and the refining rate is lower. At the same time, the workload of the refining process will increase accordingly.
3. Increase in investment
Since the solvent used in the solvent extraction production process is flammable and explosive, and harmful to humans, the fire hazard category of the production workshop building should be Class A, and the minimum fire resistance rating should be Class II. The workshop equipment must be grounded, the electrical appliances used must be explosion-proof, and the workshop must be equipped with lightning protection devices. In addition, the equipment and pipelines in the workshop need to be strictly sealed, etc. In this way, the construction of the entire solvent extraction workshop will increase the total investment.
