- Technical contribution
In one of Germany’s largest and most modern beer pasteurization facilities plate heat exchangers from Kelvion are used to guarantee both the taste and purity of the beer.
Pasteurizing beer is a task that requires great finesse. The art lies in adhering to strict hygiene regulations while retaining the superb taste and high quality of the beer. While heating the beer does kill harmful bacteria, heating it for too long or at too high a temperature can detract at least minimally from the taste of the beer and can also make it turn a darker color. Thus every master brewer takes great care during the pasteurization process, the last step before bottling the beer.
This is particularly true of one of the largest and most modern breweries in Europe, the Binding Brauerei AG in Frankfurt, Germany, which belongs to the Radeberger group. Although beer consumption is decreasing in Germany, the Binding brewery has managed to buck the trend, increasing its capacity considerably over the last several years. That created the need for a new pasteurization plant. The contracted EPC contractor specializes both in measurement technology in breweries and in the construction of short-term heaters for the pasteurization of beer.
The plant utilizes short-team heating methods to pasteurize the beer, using plate heat exchangers. Cooling components of this type are space-and energy-efficient. In applications with a high risk of fouling or scaling, e.g. due to high temperatures, hard water, or high pH levels, cleaning of the gasketed plate heat exchanger may be required to maintain efficiency. This is achieved quickly and easily with Cleaning in Place (CIP), a method of cleaning the interior surfaces of closed systems, such as pipes, vessels, process equipment, and filters, by circulating a liquid.However, the short-term heating method does require that high standards of temperature control are maintained. This is why the EPC contractor bases the plant's short-term heat generation on gasketed plate heat exchangers from Kelvion. The company, based in Sarstedt, Germany, can look back on over 85 years of expertise in this industry, particularly in pasteurization.
There are three stages involved in the heating and cooling of the beer during pasteurization, that take place in three different areas: In the first area, the freshly brewed beer, with a temperature of 3°C, is heated to 67°C in a heat exchanger. In the second area, using precisely controlled hot water, the beer is brought up to the pasteurization temperature of 72°C, which is maintained in the connected heat-holding area for a specified period of time. The holding period is from 30 seconds to one minute at the maximum. Next, the beer is cooled down in the regeneration zone, in which 97 percent of the utilized energy is recovered. The beer now has a temperature of 7°C, and in the next step is cooled down to 2°C. This cooling zone uses propylene glycol as a coolant in contrast to the earlier stages. However, there were further issues to solve. The Binding brewery not only values the choice of its raw materials but also the use of resources and their treatment.
Thus the heat exchangers in the pasteurization plant are not heated with steam but with hot water. This is available from the previous brewing processes and has a temperature of 180°C - apparently much too hot for the beer, as it would caramelize immediately.
Therefore, the contractor installed a second gasketed plate heat exchanger with an area of 11 square meters and equipped with a working pressure of 10 bar(g). The plate heat exchanger heats circuit water by means of the available hot water of 180°C to a temperature of 70 - 75°C only. The circuit water is used in the plate heat exchanger to heat the beer without compromising the quality.