Coffey still

Low Wines. Low wines is the term for the initial product obtained by separating (in a pot or Coffey still) the beverage spirits and congeners from the wash. Low wines are subjected to at least one more pot still distillation to attain a greater degree of refinement in the malt whiskey. 

Coffey stills operating 32 hours rate per hour—17,187 gallons... 

Prentice, R.D.M. J.H. Bryce. A source of dimethyl disulfide and dimethyl trlsulfide in grain spirit produced with a coffey still./. Am. Soc. Brew. Chem. 1998, 56, 99-103. 

Figure 13. The Coffey still of 1830 for distilling alcohol from fermented mash, using perforated plates. 1, Boiler. 3, Stripping column. 4, Rectifying column. 6, Feed. 8, Condenser.

Figure 13). In such a still 85% ethanol could be produced from an initial 5% of ethanol. The Coffey still was the forerunner of the modem column, and its efficiency in separating close-boiling fractions led later to its adoption for hydrocarbon separations, e.g. Coupiers benzole still (1863) for purifying benzene from toluene. Partial condensation also improved the separation achieved in the Coupier still.

Figure 6.1 The Coffey still for the separation of ethanol from a fermented beer mash 1, boiler 2, spent mash chamber 3, stripping column (analyser) 4, rectifying column 5, residual mash (stillage) outlet 6, fermented mash (feed) 7 feed pump 8, condenser 9, product tank. From Packowski, G. I. (1978), in Encyclopedia of Chemical Technology, Vol. 3, 851... 

In many of the still-heads employed on the large scale, for example the Coffey still (Fig. 58, p. 202) the condensed liquid is made, by means of suitable obstructions, to collect into shallow pools, and the ascending vapour has to force its way through these pools very good contact is thus brought about at definite intervals between vapour and liquid. The excess of liquid is carried back from pool to pool, and finally to the still by suitable reflux tubes. It is convenient to reserve the term dephlegmator for this particular class of still-head. 

Continuous Distillation on Large Seale.—Continuous distillation of wort has long been carried out on the large scale by means of the Coffey still (p. 202) but it is only quite recently that any attempt has been made to devise a process of the kind suitable for laboratory purposes. 

The Coffey Still.—Various alterations in the still have been made in order to make the process of distillation a continuous one. In this country very strong spirit is... 

The first successful attempt on continuous distillation and improved efficiency as well as profitability was the Coffey Still in 1831. It was used to produce Whisky. The Coffey Still consists of two columns called analyser and rectifier. The fermented feedstock is preheated against condensing vapours in the rectifier and fed at the top of the analyser. The liquid flows over a copper plate with openings and from there into a down-comer leading onto another, underlying plate, and so on. More than 10 perforated plates (called trays) are typically installed in the analyser. 

There are two kinds of Scotch whislg malt whisky, which is made by the pot still process, and grain whisky, which is made by the patent still (or Coffey still) process. Malt whislq is made from malted barley only, whereas grain whislg is made from malted barley together with unmalted barley and other cereals. 

AIChE (American Institute of Chemical Engineers) Chemical Professional s Code of Conduct, 831. 832-833 Coffey stills, 92 Colburn equation, 636-639 Cold utilities, HENs (heat-exchanger networks) minimizing, 529-530 minimum approach temperature, 526 multiple utilities, 558 pinch points, 529-530 Cold zones, 712. 714... 

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