I. Overview

　　 Five towers and three effects is a new energy-saving technology launched on the basis of traditional five towers differential pressure distillation, mainly used for the production of premium grade alcohol. The main equipment of traditional five-tower differential pressure distillation includes crude distillation tower, dilution tower, rectification tower, methanol tower, and impurity tower. The heating method is that the rectification tower and the dilution tower are heated by the primary steam through the reboiler, and the rectification tower wine vapor supplies heat to the crude distillation tower through the reboiler. The dilution tower wine vapor supplies heat to the methanol tower through the reboiler. The impurity tower uses primary steam for direct heating, which consumes a lot of steam. The main equipment for five-column three-effect differential pressure distillation is also a crude distillation tower, dilution tower, rectification tower, methanol tower, and impurity tower.

2. Process characteristics

　　 1. The three-effect thermal coupling process of heating the dilution tower, the methanol removal tower, and the impurity tower by the refined tower, and then heating the crude distillation tower by the dilution tower and the methanol removal tower minimizes steam consumption. It consumes 2.2 tons of premium alcohol vapor to produce one ton.

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

　　3. The reboiler of the rough distillation tower adopts thermosyphon circulation heating technology to replace the forced circulation heating method, which has a significant power saving effect and eliminates the blockage of the reboiler heat exchange tube.

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

3. Heating method

　　The key to energy saving of this process lies in its heating method. The primary steam passes through the reboiler to heat the distillation tower. The wine vapor of the rectification tower supplies heat to the methanol tower and the dilution tower through the methanol tower reboiler and the dilution tower reboiler respectively. The diluting tower and methanol tower wine vapors pass through the rough distillation tower reboiler A and B to heat the rough distillation tower. Distillation tower wastewater flash steam heating impurity tower. One tower enters steam and five towers work, so as to realize three-effect thermal coupling and achieve energy saving purpose. It consumes 2.2 tons of premium alcohol vapor to produce one ton.
Fourth, the material trend

　　 The mature mash is fed from the top of the crude distillation tower after two-stage preheating. The wine vapor at the top of the crude distillation tower is condensed and enters the dilution tower for dilution and purification. The crude alcohol is diluted to 12-18% (v/v). The light wine at the bottom of the tower enters the rectification tower after preheating, and is on the upper side of the rectification tower. Take out the alcohol (96% (v/v)) into the methanol removal tower, after further removing methanol and other impurities, take out the finished alcohol from the bottom.

Five, other advantages

　　1. In terms of power saving, the forced circulation heating method is replaced by the thermosiphon reboiler circulating heating method, and our technology is used to avoid the clogging of the reboiler heat exchange tube. The electricity consumption per ton of alcohol is 20kwh, which saves 50% of electricity compared with the improved differential pressure distillation 40-45kwh of the first five towers, avoids the maintenance of the forced circulation pump of the reboiler, and extends the service life of the reboiler.

2. Impurity wine processing: impurity alcohol from crude distillation tower, dilution tower, methanol tower, etc. and light wine from fusel oil separator enter the impurity tower, and extract industrial alcohol after the impurity tower condenser is drained, the middle and lower parts The fusel oil is extracted, and the crude alcohol taken from the upper side line enters the dilution tower to increase the yield of super premium alcohol.

　　3. In terms of improving the quality of alcohol, in addition to technological measures, the equipment structure has also been improved. The crude distillation tower is equipped with a crude wine purification device, and the rectification tower is equipped with a copper filler desulfurization device to ensure the purity and taste of the alcohol.


Double crude tower three-effect differential pressure distillation process
3. Process characteristics

  1. Low energy consumption, 1.2 tons of steam per ton of alcohol.

2. The primary steam passes through the reboiler to heat the refined tower II, the wine vapor at the top of the refined tower II heats the crude tower II through the reboiler, the wine vapor from the top of the crude tower II directly heats the refined tower I, and the wine vapor at the top of the refined tower I The reboiler heats the crude column I. One tower enters steam and four towers work, so as to achieve three-effect thermal coupling and achieve energy-saving purposes.

  3. Use the differential pressure and temperature difference between the tower and the tower to exchange heat step by step through the reboiler, which can maximize the use of heat, thereby effectively saving energy.
Five, heating method

The key to energy saving of this process lies in its heating method. The primary steam heats the refined tower II indirectly through the reboiler. The steam condensed water preheats the mature fermentation mash and crude alcohol and then returns to the boiler soft water tank for reuse; the refined tower II wine vapor passes through the reboiler The crude column II is heated; the refined column I wine vapor passes through the reboiler to heat the crude column I.

  In this process, coarse column I is a negative pressure column, coarse column II and fine column I are atmospheric columns, and fine column II is a positive pressure column. Use pressure difference and temperature difference to heat step by step. One tower enters steam and three towers work, so as to realize three-effect thermal coupling and achieve energy saving purpose.
6. Material Trend

  After the two-stage preheating, the fermented mash first enters the top of crude column I for dealdehyde, and then divides the mash into two parts by the distributor: one part enters the crude column II, and the other part enters the crude column I. After the fermented mash enters the crude tower II, the lees is discharged from the bottom of the tower, and the crude alcohol gas enters the refined tower I for concentration and impurity removal, and part of the finished alcohol is taken out from the upper side line.

The light wine at the bottom of the refined tower I and the wine vapor condensate at the top of the crude tower I are mixed and enter the refined tower II, where it is concentrated and drained, and part of the finished alcohol, fusel oil and other high-boiling impurities are taken out from the upper side of the tower. Take it out from the lower part of Jing Tower II.