Distillation Process (Five-tower Three-effect Differential Pressure)

Five column three effect differential pressure distillation process

I. Overview

Five column three effect is a new energy-saving technology based on the traditional five column differential pressure distillation, which is mainly used in the production of extra high grade alcohol. The main equipment of traditional five-column differential pressure distillation includes crude distillation column, dilution column, rectification column, methanol column and impurity column. The heating method is that the distillation tower and dilution tower are heated by the primary steam through the reboiler, and the distillation tower wine steam is heated by the reboiler to the crude distillation tower. The liquor steam in the dilution column is heated by the reboiler to the methanol column, and the impurity column is heated by the primary steam directly, and the steam consumption is large. The main equipment of five-column three-effect differential pressure distillation is also a crude distillation tower, dilution tower, rectification tower, methanol tower, and impurity tower.

II, process characteristics

1. Adopt the three-effect thermal coupling process of fine tower heating dilution tower, demethanol tower and impurity tower, and then dilution tower and demethanol tower heating crude distillation tower to reduce steam consumption. The steam consumption of producing tons of superior alcohol is 2.2 tons.

2. The upper part of the crude distillation tower is provided with a degassing section and a separator to reduce impurities such as solids contained in the crude alcohol entering the rectification system and improve the purity of the crude alcohol.

3. The reboiler of the crude distillation tower adopts the patented thermosiphon cycle heating technology to replace the forced cycle heating mode, which has significant power-saving effect and prevents the blockage of the reboiler heat exchange tube.

4. Copper Pall ring filler is added to the distillation system to improve the taste and quality of the finished alcohol.

III, heating method

The key to saving energy in this process is its heating method, in which a steam is heated through a reboiler to the rectifying column. Distillation column liquor steam through the methanol column reboiler and dilution column reboiler respectively heating methanol column and dilution column. The liquor steam of the dilution column and the methanol column is heated by the reboiler A and B of the crude distillation column respectively. Distillation tower waste water flash steam heating impurities tower. One tower inlet steam, five towers work, so as to achieve three effects of thermal coupling, to achieve the purpose of energy saving. The steam consumption of producing tons of superior alcohol is 2.2 tons.

IV. Material direction

The fermented mash is fed from the top of the crude distillation tower after two stages of preheating. The liquor vapor at the top of the crude distillation tower is condensed into the dilution tower for dilution and purification, and the crude alcohol is diluted to 12-18%(v/v). The light liquor at the bottom of the tower is preheated and enters the rectification tower. The alcohol (96% (v/v)) is removed from the upper side of the rectification tower into the demethanol tower, and the finished alcohol is removed from the bottom after further removing impurities such as methanol.

V. Other advantages

1. In terms of power saving, the thermosiphon reboiler cycle heating method replaces the forced cycle heating method, and the use of our patented technology avoids the blockage of the reboiler heat exchange tube. Tons of alcohol consumes 20kwh, compared with the improvement of the first five tower differential pressure distillation 40-45kwh, saving 50% of electricity, avoiding the forced circulation pump maintenance of the reboiler, but also extending the service life of the reboiler.

2. Impurity liquor treatment: The impurity alcohol from the crude distillation tower, dilution tower, methanol tower, etc., and the light wine from the fusel oil separator enter the impurity tower. After the impurity is discharged by the condenser of the impurity tower, the industrial alcohol is extracted, and the fusel oil is extracted from the middle and lower part of the impurity tower.

3. In terms of improving the quality of alcohol, in addition to the process measures, the equipment structure has also been improved, the crude distillation tower is set up a crude wine purification device, and the rectification tower is set up a copper filler sulfur removal device to ensure the purity and taste of alcohol.

VI, superior alcohol energy consumption and quality comparison table