After alcohol is used as a solvent for osmosis and reflux concentration, its concentration is inevitably greatly reduced, and it contains a large amount of dregs and other impurities. In order to reduce consumption and reduce costs, the alcohol is reused in time, not only to remove the drug in the mother liquor. Slag and other impurities, and must increase the alcohol content to a certain extent.
The structure of the alcohol recovery tower is composed of six parts: tower kettle, tower body,
Condenser, cooler, buffer tank and high-position storage tank. It has good corrosion resistance, energy saving, environmental protection, low production cost and high efficiency. advantage. The dilute alcohol of 30 degrees to 50 degrees can be distilled to 93 degrees to 95 degrees, the residual liquid discharge has low alcohol content, and the alcohol recovery tower meets environmental protection requirements. The device adopts high-efficiency stainless steel corrugated packing, and all the contact materials are made of stainless steel, outside the equipment. Surface matt treatment, in line with GMP pharmaceutical standards.
Using the principle that the boiling point of alcohol is lower than the boiling point of other solutions, the diluted alcohol solution to be recovered is heated and volatilized at a temperature slightly higher than the boiling point of alcohol. After the tower is refined, pure alcohol gas is precipitated to increase the concentration of the alcohol solution. Reach the purpose of recycling alcohol. The alcohol recovery tower is suitable for the recovery of dilute alcohol in the pharmaceutical, food, light industry, chemical and other industries. Also suitable for distillation of other coal-soluble products such as methanol. The alcohol recovery tower cools the ethanol gas with circulating cooling water and condenses to obtain recovered ethanol. Of course, it is not possible to condense all at once, or to connect several recovery towers in series, or to condense them in sections inside the tower and recycle them in sections. If it is an
Absorption Tower, it depends on whether ethanol is absorbed or because it is a product or an accompanying product. Condensation can be carried out at different temperatures using different condensation points of organic materials to obtain different products.
1. The alcohol is recycled to the distillation pot to 1/2-2/3 tank for operation.
2. Open the steam valve for heating (gauge pressure 0.2-0.5 MPa) to allow the ethanol vapor to enter the column.
3. Turn on the condenser cooling water and the coil cooler cooling water, so that the ethanol vapor in the tower enters the condenser and condense into a liquid, and open the reflux valve to allow the condensate to flow back into the tower.
4. When the temperature at the top of the tower is stable below 78.5 °C, open the discharge valve. From the flowmeter observation, control the reflux ratio of 1:2-1:3, and keep the concentration of recovered ethanol above 93%.
5. When the distillation operation, do not leave the position at will, observe the recovery of ethanol concentration at any time, adjust the reflux ratio in time, the reflux ratio is smaller when the concentration is high, and the reflux ratio is larger when the concentration is low. The recovered ethanol is brought to the desired concentration.
6. If the amount of recovered ethanol is large, a continuous feeding method may be employed. After the distillation kettle is heated to boiling, a small amount is continuously fed into the distillation pot, and the rate of addition is consistent with the rate of evaporation of ethanol.
7. At the end of the distillation, when the temperature in the distillation rises to 100~102 °C, the temperature at the top of the tower rises accordingly. At this time, the reflux valve should be closed, the steam flow rate of the distillation pot should be appropriately increased, and the residual ethanol in the kettle and the column should be distilled off. Collected in a dilute ethanol storage tank and distilled together into the next batch of dilute ethanol.
