A major US brewery needed to automate tank cleaning in large horizontal primary fermentation tanks for cost savings and increased production. The current method used a combination of manual entry and three tank cleaning machines on portable carts. The carts were hooked in series and fed through the manway on the front of the tanks. The existing cleaning procedure took close to two hours. The manual entry and physical requirements made tank cleaning lengthy, cumbersome and dangerous.
A project was started to evaluate the cost benefit analysis of permanently mounting two Alfa Laval GJ 4 machines suspended from the ceiling of each fermenter. By choosing dual nozzle units with larger orifices instead of triple nozzle units with smaller orifices, the flow per cleaning jet was drastically increased. This additional impact allowed the brewery to only install two cleaning heads instead of three.
The total flow rate used was decreased by 33%. The increased impact and jet throw length provided excellent cleaning performance at a major reduction of flow rate. The total cleaning time was reduced from two hours to less than 30 minutes. Since the cleaning process was automated, personnel could be better used in more productive tasks. By decreasing the cleaning times, the brewery could produce more product using existing equipment. Estimated water savings are 3.2 million gallons per year.