RU2277432C2 - Method of production of rectified alcohol - Google Patents

Abstract

FIELD: alcohol industry.

SUBSTANCE: proposed method includes boiling-out alcohol from distiller's wart in wart column at conversion of ethyl alcohol and by-products to distiller's wart with vapor from this column, cleaning distiller's wart from overhead and intermediate admixtures including fusel oil components in intermediate fractionating column at delivery of hot water to its upper plate. Then, fractionation intermediate product is subjected to rectification in alcohol column at extraction of fractions of fusel oil, fusel alcohol and non-pasteurized alcohol, distillation of fractions of ethyl alcohol overhead and intermediate fractions in distillation column. Fractions from condensers of wart, alcohol and methanol columns, carbon dioxide separator and alcohol traps are directed to upper plate of distillation column. Fraction of fusel alcohol from alcohol column, water layer of liquid from wart scrubber and hot water for hydraulic selection of overhead and intermediate admixtures are fed to center zone of concentration part of distillation column. Concentrate of overhead admixtures is taken for distillation column condenser. Intermediate admixture concentrate is withdrawn from liquid phase of plate above distillation column inlet point. Still liquid of distillation column is directed to center zone of concentration part of intermediate fractionating column.

EFFECT: improved quality of alcohol.

1 dwg, 1 tbl, 2 ex

Description

The invention relates to methods for producing ethanol.

A known method for the production of ethanol, involving the digestion of alcohol from a mash in a distillation column with the passage of ethyl alcohol and associated impurities into a macerated distillate with steam from this column and liquid fractions from a condenser of a carbon dioxide separator and an alcohol trap, the separation of impurities from macerated distillate in a hot column water into the middle zone of its concentration part and the selection of the side fraction from the hydroselection zone, which, together with the fusel oil and fusel alcohol fractions from Irta columns are rectified in a fuselage column (V.L. Yarovenko, B.A. Ustinnikov, Yu.P. Bogdanov, S.I. Gromov. Alcohol production reference book. Raw materials, technology and technochemical control. Moscow. Light and food industry, 1981 . P. 138).

However, this method does not provide the opportunity to improve the quality of rectified alcohol, since in the process of epuration there is an incomplete release of methanol, components of fusel oil and other intermediate impurities. These impurities pass with the epure into the alcohol column and partially get into the final product, reducing its quality.

Closest to the proposed method is the production of ethyl alcohol, which involves purification of the distillate from head and intermediate impurities, including fusel oil components, in an epilation column with hot water supplied to its upper plate, distillation of the epureate with selection of fusel oil, fusel alcohol and non-pasteurized fractions alcohol, distillation of fractions containing mixtures of head and intermediate impurities in the first booster column, followed by separation of the concentrate of head impurities in the upper part a second booster column, fusel oil and propyl alcohol concentrate in the lower part of this column and returning to the mash the ethyl alcohol fraction from its middle zone (V. M. Perelygin, N. A. Porokhov. Method for producing rectified alcohol. RF patent No.2166346 on application No. 99125833/13, 12/15/1999, B 01 D 3/14).

However, this method does not provide deep purification of alcohol from isopropyl alcohol and n. propyl alcohol and requires additional costs for equipment and heating of two booster columns, which limits the possibility of improving the quality and lowering the cost of obtaining rectified alcohol.

The objective of the invention is to obtain ethyl alcohol of high quality with reduced costs for its production.

This problem is achieved by the fact that along with the digestion of ethyl alcohol from the mash in the mash column with the transition of ethyl alcohol and associated impurities to the mash distillate with steam from this column, purification of the mash distillate from head and intermediate impurities, including fusel oil components, in the emulsion column with by supplying hot water to its upper plate, rectification of the epureate in an alcohol column with the selection of fractions of fusel oil, fusel alcohol and unpasteurized alcohol, distillation of fractions containing mixtures of heads of impurities and intermediate impurities, in the booster column, according to the proposed method, fractions from the condensers of refined, alcohol, methanol columns, a carbon dioxide separator and alcohol traps are sent to the upper plate of the booster column, a fraction of fusel alcohol from the alcohol column is fed into the middle zone of the concentration part of this column, water a layer of liquid from the sivuhomoplivatel and hot water for hydroselection of head and intermediate impurities, from the condenser of the booster column, a concentrate of head impurities is taken from liquid of the phase of the plate above the point of entry into this column of hydroselective water, a concentrate of intermediate impurities is discharged, and the bottom liquid of the booster column is sent to the middle zone of the concentration part of the epilation column.

The drawing shows a process flow chart rectification, explaining the proposed method.

The original mash is heated to 80-85 ° C in the cookers 20 and 4 and fed to the separator 2, where carbon dioxide containing vapors of the mash is released from it. Carbon dioxide is purified by vapor condensation in condenser 3 and removed from the distillation unit, and the condensate formed, containing significant amounts of methanol, esters, aldehydes, fusel oil and other impurities, is sent together with the liquid from the alcohol trap of dirty shoulder straps to the upper plate of the booster column 11. Separated mash is served on the upper plate of the mash column 1, where ethanol and volatile impurities are boiled from it. Steam from the top plate of the mash column 1 is sent to the mash 4 and water 5 sections of its reflux condenser, where during its condensation, the head and intermediate impurities are concentrated, which are removed from the condenser 6 with the fraction and sent to the upper plate of the booster column 11. The mug distillate from the heat exchangers 4 and 5 feed the epilation column 7, equipped with a reflux condenser 8, a condenser 9 and a boiler 10. On the upper plate of the column 7, hot water is supplied from the tank 15 in such a quantity that the alcohol concentration in the epoxide is set 16-20% vol. This provides a strong increase in the evaporation rates of all ethanol impurities. The components of fusel oil and other intermediate impurities acquire a head character on all plates of column 7. Therefore, in column 7 deep alcohol is cleaned from head impurities, fusel oil and other intermediate impurities, which are taken with a fraction from condenser 9 and sent to the power plate of the booster column 11 From the cube of column 7, the epuret is removed, which feeds the alcohol column 19 with a reflux condenser having a brew 20 and a water section 21, a condenser 22 and a boiler 16. Concentration is carried out in column 19 pyurata and alcohol purification from accompanying impurities. From the vapor phase of the lower 5-11 plates, the fusel oil fraction is taken and fed to the fusel condenser 17, the liquid from which is sent to the vortex washer 18, from the upper part of which the fusel oil is taken, and the aqueous layer is sent to the middle zone of the concentration part of the booster column 11. From the condenser 22, a fraction of unpasteurized alcohol is removed and fed to the upper plate of the booster column 11. From the liquid phase of the lower plates of the strengthening part of the column 19, the fusel alcohol fraction is taken and sent to the middle zone of the concentration tea these columns 11. Rectified alcohol is taken from the liquid phase of the upper plates of the reinforcing part of the column 19 and sent to the food plate of the methanol column 24 with a reflux condenser 25, a condenser 26 and a boiler 23. Column 24 is designed for deep purification of alcohol from methanol and head impurities, which are taken from the methanol fraction from the condenser 26 and served on the upper plate of the booster column 11. In the booster column 11 with a reflux condenser 12, a condenser 13 and a boiler 14, the fractions are separated from the condensers 3, 6, 9, 22, 26, alcohol traps, fusel alcohol from the column 19 and an aqueous layer of liquid from the vortex scrubber 18. To increase the evaporation coefficients of the head and intermediate impurities, hot water is supplied to the middle zone of the concentration part of the column 11, which improves the digestion and concentration of impurities in this column.

Concentrate of head impurities (CGP) is taken from the condenser 13 of column 11, intermediate concentrate of impurities (CCP) is removed from the liquid phase of the plate above the point of introduction of the hydroselective water into column 11, and bottoms liquid of the booster column 11 is sent to the middle zone of the concentration part of the emulsion column 7.

According to the known method, the distillation of fractions containing mixtures of head and intermediate impurities is carried out in an accelerating column operating without hydroselection. This does not allow the propyl alcohols to be sufficiently boiled in this column, to concentrate them and to remove them from the recovery system with a fraction taken from its condenser, which reduces the quality of the final product.

According to the proposed method, the booster column operates by the method of deep hydroselectivity, which improves the digestion and concentration of head impurities, propyl alcohols and other intermediate impurities, ensures their effective removal from the recovery system by selecting the fraction of KGP and KPP and improves the quality of rectified alcohol in comparison with the known method.

According to the known method, the distillation of the intermediate fractions of ethyl alcohol is carried out in two booster columns, each of which is heated with hot steam, which increases the cost of obtaining high-quality alcohol.

According to the proposed method, sharp steam is spent only on heating one booster column, which reduces the cost of obtaining the final product of high quality in comparison with the known method.

Comparative indicators of the process for producing rectified alcohol, according to the prototype and the proposed method, are reflected in examples 1, 2 and are presented in the table.

Example 1. Rectified alcohol is obtained according to the prototype.

Example 2. Rectified alcohol is obtained according to the proposed method.

As follows from the above examples, the proposed method allows to remove more impurities from the system of rectification, to obtain rectified alcohol of better quality and at lower cost compared to the known method.

Table Indicators of the process of rectification in the calculation of absolute alcohol Example 1 Example 2 Impurities in the bottoms liquid of the booster column, mg / dm ³ Methanol 3.0 3.0 Esters 0.5 0.2 Aldehydes 3.0 0.5 Isoamyl alcohol 4800 4100 Isobutyl alcohol 1200 1800 N. Propyl alcohol 600 2.5 Isopropyl alcohol 3.0 1.5 Impurities in the liquid from the condenser of the booster column, mg / DM ³ Methanol 28800 29000 Esters 9600 11500 Aldehydes 5400 12000 Isoamyl alcohol 10 8100 Isobutyl alcohol 150 22000 N. Propyl alcohol 500 24000 Isopropyl alcohol 12 500 Impurities in the liquid in the final product, mg / DM ³ Methanol 0.5 0.3 Esters traces traces Aldehydes traces traces Isoamyl alcohol traces traces Isobutyl alcohol traces traces N. Propyl alcohol 0.2 0.15 Isopropyl alcohol 0.5 0.4 Consumption of heating steam for distillation correction, kg / dal of absolute alcohol 67 60

Claims (1)

A method of producing ethanol by digesting alcohol from a mash in a mash column with the passage of ethyl alcohol and associated impurities into a mash distillate with steam from this column, purifying the mash distillate from head and intermediate impurities, including fusel oil components, in an emulsion column with hot water supplying to it the upper plate, distillation of the epureate in an alcohol column with the selection of fractions of fusel oil, fusel alcohol and unpasteurized alcohol, distillation of the fractions of head and intermediate impurities of ethyl alcohol in the booster column, characterized in that fractions from the condensers of the reflux, alcohol, methanol columns, the carbon dioxide separator and alcohol traps are sent to the upper plate of the booster column, a fraction of fusel alcohol from the alcohol column, an aqueous layer of liquid from the vortex washer are fed to the middle zone of the concentration part of this column hot water for hydroselecting the head and intermediate impurities; from the condenser of the booster column, the concentrate of head impurities is taken from the liquid phase of the plate above the entry point into this col Concentrate of intermediate impurities is withdrawn from the hydroselective water, and bottoms liquid of the booster column is sent to the middle zone of the concentration part of the epilation column.