JPS6013676B2 - Gas-liquid contact shelf for distillation of fermented alcohol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a gas-liquid contact shelf for distillation of fermented alcohol, more specifically, a gas-liquid contact shelf for distillation of fermented alcohol, and more specifically, a gas-liquid contact shelf for distilling fermented alcohol. This invention relates to a gas-liquid contact shelf for distilling fermented alcohol that can be side-drawn extremely efficiently.

Refined ethanol, which is obtained from fermented acids through various distillation processes, is widely used for alcoholic beverages, medicines, cosmetics, etc., and today it is also used as a fuel source for internal combustion engines by mixing it with gasoline. It is highly anticipated that it will be economically viable.

However, ethanol-
In addition to water, acetaldehyde, methanol, ethyl acetate,
It contains various impurities consisting of low-boiling point components, medium-boiling point components, and high-boiling point components such as diacetyl, acetal, amyl acetate, propyl alcohol, amyl alcohol, and acetoine, and also contains fermented acids from sulfite pulp waste liquid raw materials. also contains furfural and terbene impurities.

Therefore, impurities from the fermented acid must be separated. Conventionally, various improved gas-liquid contact shelves have been provided to improve the gas-liquid contact efficiency mainly from the viewpoint of energy saving, and various distillation systems incorporating distillation columns containing multiple stages of these gas-liquid contact shelves have been provided. A retention method is provided.

In any of these distillation methods, low-boiling components and high-boiling components can be separated relatively easily, so obtaining ethanol efficiently and with a high degree of purification means that the behavior is relatively different from that of the ethanol-water system. It is concerned with how to separate similar medium-boiling components. However, as mentioned above, conventional gas-liquid bag contact shelves have been improved to improve the gas-liquid contact efficiency mainly from the viewpoint of energy saving, and therefore do not incorporate distillation columns containing multi-stages. In the double distillation method, it cannot be said that medium-boiling components are separated efficiently. For example, in the super allospass system that is most commonly used today, medium-boiling components are usually side-drawn as fusel oil from the middle of the A2 column (concentrating column) and the B column (one of the distillation columns). However, the highest concentration of fusel oil is about 6%.

By providing a gas-liquid contact shelf capable of accumulating such fusel oil at a high concentration in a specific area of a distillation column, the present invention ultimately achieves even more efficient and highly purified ethanol. As a result of this lever, it also saves energy, and its gist is that it is equipped with a partition plate that divides the inflow part, the gas-liquid contact part, and the overflow part in the gas-liquid contact shelf into two parts. The point is to prevent the liquids on both sides from directly buffering each other.

Hereinafter, the configuration of the present invention will be explained in detail based on the drawings while comparing it with the conventional case.

FIG. 1 is a process diagram of the super allopath method.

The fermented scales are fed to the top of the column A, passed through various distillation columns, and purified to 96% ethanol from the bottom of the column C.The details are as known in the past, and during this time, The above-mentioned impurities other than ethanol-water are separated by the following various methods.First, in the D column and the D column, low boiling point components and higher alcohols are separated by hydroextraction. tower, F tower and B,
In the closed bottom part, components with higher boiling points than water are separated.

Furthermore, in the final G tower, methanol, which is easily entrained with ethanol, is separated. The medium-boiling components other than these impurities are accumulated in the middle part of the A2 tower and the B tower, and after being side-drawn from the corresponding group of gas-liquid contact shelves, they are made into two liquid layers in a decanter, and eventually become fusel oil. Separated as However, conventional gas-liquid contact shelves built in multiple stages and B
Due to the structure of the column and the resulting flow within the distillation column, it is not possible to accumulate such fusel oils in sufficiently high concentrations.

Even in the gas-liquid contact shelf where the highest concentration is accumulated, it is usually 6%.
That's about it. The inventor of the present invention repeatedly conducted various tests to find out the cause of this problem, and found that the fusel oil that attempts to accumulate is diluted and dispersed by the supply liquid, and cannot be accumulated above a certain concentration.

Conversely, this means that the gas-liquid contact shelves should be constructed so that the fusel oil to be accumulated and the feed liquid do not directly buffer each other, and such gas-liquid contact shelves should be installed in groups at necessary locations in the distillation column. The present invention has been successfully completed by focusing on the fact that it can be built-in. FIG. 2 is a partially omitted side view showing a state in which the gas-liquid contact shelf 1 according to the present invention is used with the outer cylinder of the distillation column removed, and FIG. FIG. 2 is a plan view of a gas-liquid contact shelf 1 according to the present invention. These are all examples, but the inflow part 5 including the inflow pipe 4 is divided into the inflow weir 2 and the overflow weir 3, and the gas and liquid sandwiched between the inflow weir 2 and the overflow weir 3. A partition plate 9 is attached that divides all three parts of the overflow part 8, including the contact part 6 and the overflow pipe 7, into two parts, and the liquid on both sides divided by this partition plate 9 is divided into two parts. It has sufficient height so that they do not buffer each other. In this case, the mounting position of the partition plate 9 that divides the space into two parts is influenced by the amount of liquid, the amount of steam, etc. on the gas-liquid contact shelf. If such gas-liquid contact shelves are arranged in groups at several levels above and below, including the fusel oil side shelf,
Approximately 20% of fusel oil is side-drawn at the gas-liquid contact shelf where the highest concentration is accumulated.

Moreover, the dispersion of fusel oil throughout the distillation column is reduced,
It is also possible to reduce the number of plates and the reflux ratio. FIG. 4 is a side view schematically showing the flow state inside a distillation column incorporating gas-liquid contact shelves according to the present invention as a group.

No. in the figure. 1.No. 2 and no. 7 is a conventional gas-liquid contact shelf; 3~No. 6 is a gas-liquid contact shelf according to the present invention. The paper flowing in from the bottom of the tower in the direction of arrow c is No. From 7 to No. While being in gas-liquid contact with the gas-liquid contact shelf No. 1, the gas rises sequentially and is discharged from the top of the column in the direction of arrow d.

Thereafter, it is condensed by a condenser (not shown), and a part of it is supplied as a reflux liquid to Shikinai again in the direction of arrow b'. 1.No. The liquid flows down while being mixed freely on the second gas-liquid contact shelf. However, No. 3 to no. In the gas-liquid contact shelf No. 6, the liquid on both sides divided into two by the partition plate 9 flows down without mixing with each other. They are combined again at the gas-liquid contact shelf 7 and discharged from the bottom of the tower according to arrow e. Thereafter, a part of the paper is heated and turned into paper, which is again fed into the melt according to arrow c. The feed liquid containing the medium-boiling point component in the amount is No. 1 according to the arrow a. 5 gas-liquid contact shelf.

Of these, those with relatively high boiling points exchange heat with the rising paper and move to the upper gas-liquid contact shelf, while those with relatively high boiling points flow down. During this time, NO. 3 to no. Even in the gas-liquid contact shelf 6, if it becomes paper, it can freely move to either side of the partition plate 9, and there is always a flow of paper and reflux liquid as described above in the column.

Therefore, the mid-boiling components in the feed liquid are condensed and accumulated at each equilibrium temperature gas-liquid contacting shelf.

In this case, No. 1 with a high degree of accumulation. 3~No
．． In the gas-liquid contact shelf 6, medium-boiling point components are accumulated at a high concentration on the right-hand side in the figure, which is divided into two parts by the partition plate 9, which is not directly affected by the feed liquid. Finally, specific effects of the gas-liquid contact shelf according to the present invention will be illustrated.

Figure 5 is a graph showing the results, with the number of stages on the rattan axis and the concentration of the fusel oil drawn out as fusel oil on the vertical axis. In this system, using a 68-yen B tower (one of the distillation towers), the gas-liquid contact shelves according to the present invention are installed at locations from 1 to 30 stages from the bottom, and among these, 14 stages to 2 miscellaneous stages are installed. A sample nozzle was provided on each gas-liquid contact shelf to measure the degree of fusel oil accumulation in the liquid on both sides divided by a partition plate.

As is clear from this figure, the part on one side divided into two by the partition slope, which is not directly affected by the feed liquid, has an extremely high concentration of fusel oil that is extracted from the side. It is known that medium-boiling components, which are impurities that can be removed, are accumulated.

As explained above, in the present invention, by providing a gas-liquid contact shelf with a partition plate that is divided into two so as not to be directly affected by the feed liquid, this can be used as a part of the distillation column. When used, the medium boiling point components are accumulated in an extremely high concentration and intensively, and this is then side-drawn as fusel oil, ultimately resulting in extremely efficient and highly purified ether/ethanol. This also has the effect of saving energy.

[Brief explanation of the drawing]

Figure 1 is a process diagram of the conventional Super Allos Pass method, Figure 2
The figure is a partially omitted side view of the inside of a distillation column using a gas-liquid contact shelf as an embodiment of the present invention, Figure 3 is a plan view of the gas-liquid contact shelf used in Figure 2, and Figure 4 5 is a side view schematically showing the flow state inside a distillation column that incorporates a group of gas-liquid contact shelves according to the present invention, and FIG. It is a graph as an example showing the test results. 1... Gas-liquid contact shelf, 2... Inflow weir, 3...
... Overflow weir, 4 ... Inflow pipe, 5 ... Inflow section, 6 ... Gas-liquid contact section, 7 ... Overflow pipe, 8 ...Overflow section, 9...Partition plate. Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1 A group of multi-stage gas-liquid contact shelves built into a distillation column, with an inflow section, a gas-liquid contact section, and an overflow section.
1. A gas-liquid contact shelf for distillation of fermented alcohol, characterized in that it is provided with a dividing partition plate, and the liquid on both sides divided by the partition plate is prevented from directly buffering each other.