A Practical Handbook on the Distillation of Alcohol from Farm Products

by F. B. Wright

In connection with the distilling and fermenting building there are small buildings for storing the grain, malt, etc., for the storage of the alcohol and for the keeping of the various books, records, and stamps required by law. Such plants as these are located adjacent to a good clear spring or even a small brook, and preferably in a position convenient to the carriage of materials and the transportation of the whiskey or other liquor produced.

The buildings are of the cheapest construction and arranged in the manner which compels the least labor in filling the mash vats and turning the contents into spirits. There are no special mash coolers, no complicated stirrers. The “beer” as the fermented mash is called is stirred by a paddle in the hands of a strong negro and the mash is mixed and fermented by rule of thumb, without the use of any scientific appliances. Primitive, as it is, however, those small plants in certain sections of the country make money for their proprietors and serve a large number of customers. The spirits so produced are low grade, fiery and rough in taste, but the point is that alcohol may be and is so produced.

Between these simple beginnings and the elaborate plants of big distilleries there is a wide range, so wide that it is impossible within the limits of this book to go into detail. The makers of distilling apparatus furnish all grades of stills and to those contemplating erecting a plant it is suggested that their best course is to communicate with such manufacturers, giving the circumstances of the case, the particular product to be worked and the capacity desired. The object of this book is to give an understanding of the processes of distillation and of this chapter to give a general idea of the arrangement of a number of typical distilling plants, suitable for various kinds of work.

That the simple, direct-heated pot still such as referred to above, used for fifteen hundred years and over, is still used is largely due to the simplicity of its construction and operation, but its capacity is small, and its operating expense relatively heavy. It is still used for making liquors, but for industrial purposes it has been entirely superceded by concentrating and rectifying stills. A simple form of the latter is found in the still shown in Fig. [11] and in the distilling apparatus of Adam (Fig. [9]).

Originally all stills were heated by direct contact with fire. This was open to a serious objection, namely, that the mash if thick was liable to be scorched. Stirring devices were used by Pistorious but these required constant attention. As a consequence, direct firing gave place to heating by steam, by which not only was scorching of the wash avoided but much greater certainty of operation was attained.

The steam may be used to simply heat the boiler, thus taking the place of the direct heat of the fire, but it is far better in every way to admit the steam directly to the mash as in the Coffey still, Fig. [18], and all modern stills. It is possible to apply this principle to all compound stills, but the best results with greatest economy of fuel are, of course, gotten from the plate or column stills especially constructed for steam. In order to get the best results it is necessary that the entry of steam be regulated so that there may be absolute uniformity of flow. A convenient form of regulator is that invented by Savalle, and described on page [70], hut there are a number of other forms on the market each one having its special advantages.

It will be seen then that while the simple pot still, fire-heated, may be used, the practical plant for the fermentation of industrial alcohol should have a modern continuous still and rectifier and a boiler for generating the necessary steam for it and for the operations of mashing and fermenting.

The Fermenting Room.

The fermenting room has three main requirements for successful commercial distillation. It must allow a uniform temperature to be maintained in the vats; it must have thorough ventilation without any draftiness, and it must be absolutely clean. It should have also plenty of light so that it may be thoroughly inspected. It is true that in the primitive plants all these requisites were violated, but there is no reason for this. The first cost is but little added to by building with these requisites in mind and it is far more profitable in the long run; and it is only by the elimination of the bacteria which are inimical to proper fermentation that the fermenting operation can be performed with any certainty.

For the regulation of the temperature reliance may be had on stoves or heaters, or on special mash heaters and coolers by which the temperature of the mash in the tubs may itself be controlled without reference to the temperature of the fermenting room. When, however, no special and adequate-heating means is provided, the walls should be double with an air space between and the doors and windows should either be also double or limited in number.