Brewing - water

Wort boiling and trub separation

If a condenser is employed in the copper stack, meter cooling water flow

• Optimise flow to achieve process objective with minimum water use
• Consider how to use recovered heat

Recovery of wort from trub is possible

• Decanter centrifuge
• Possibly crossflow microfiltration
• Requires economic evaluation; more feasible on the large scale

Is it possible to reduce wort boiling time?

• Several product quality questions e.g. volatile off-flavour removal, trub formation, colour etc.
• Potential water (and energy) savings

Confirm equipment uses water at its recommended consumption

• If higher savings are possible

Clean immediately after processing to avoid hardening of deposits

Case study: Hertel rectification wort boiling system in Alpirsbacher Klosterbraeu

Alpirsbacher Klosterbrau installed a rectifying column on their wort boiler. Rectifying columns are usually associated with the distilling process, increasing the speed that unwanted compounds are removed. The rectifying column is compatible with almost any boiler. Total energy savings were 80% in the boil and 25% across the brewery. Evaporation loss was also reduced to 2% resulting in savings in water for mash in.

Hertel, M., Dillenburger, M., Glauner, C. and Wadislohner, H., Brauwelt, 4 Aug. 2011, 151(31/32), 970-973.

Case study: Research paper: Sustainable technology in the brewhouse.

Examples of innovations in brewhouse equipment, all developed in Germany and designed to improve the energy efficiency of wort production, are described. They are (1) the Krones Steinecker "Shakesbeer" vibrating mash stirrer, (2) the Rolec "ESS" brewhouse vapour energy recovery system and (3) the Kaspar Schulz "SchoKo" wort boiling and unwanted volatile constituent evaporation system and its small scale variant for microbreweries, the "SchoKolino" (also called the "GentleBoil" and "GentleCraftBoil" respectively when exported to English speaking countries). The first and last of these have already been extensively described in the literature, but the "ESS" is a more recent innovation. It consists of a vapour condenser combined with a heat storage tank, the water in which is heated to 95 degrees C by the energy recovered from the vapour of each brew.
When the next brew is lautered, the hot water is circulated through a heat exchanger built into the pipe that connects the lauter tun to the wort copper, thus preheating the wort from its lautering temperature of about 74 degrees C to just under 93 degrees C, so that bringing it to the boil requires only about a quarter of the energy input that would be needed to heat it directly from lautering temperature to boiling point. Wort preheating lowers the temperature of the heat storage water to about 74 degrees C, from which it is again heated to 95 degrees C when the vapour from the boiling of the preheated wort is condensed.
Unlike conventional vapour energy recovery systems, in which some of the heated water is used as mashing and sparging liquor but the volume of water required to take up the recovered heat is usually significantly greater than the brewhouse's liquor consumption (so that a quantity of surplus water is generally wasted, together with its recovered energy content), the "ESS" uses all the recovered energy without any loss of water.

Dornbusch, H., New Brewer, July/Aug. 2009, 26(4), 40-45