Scotland is world famous for its whisky, the character of which in some mysterious way is affected by the shape of the characteristic copper pot stills in which it is produced. The liquid, which comes in many variants, is often described by connoisseurs as having notes of smoke, peat, vanilla and caramel. Steam is never mentioned!
Nevertheless, it plays a crucial role in the whisky production process at William Grant & Sons’ site in Girvan, 90 kilometres south of Glasgow.
“We use steam for all aspects of cooking the wheat,” explains Scott Curran, Maintenance Team Leader. Every week, 5,000 tonnes of grain is processed in the production of more than 100 million litres of alcohol a year, and when the wheat grain is ready for distillation, steam is used for extracting the alcohol.
However, Grant’s steam production has faced big challenges due to difficulties in controlling the water levels in the steam boiler. According to Scott Curran, the lack of control led to huge inefficiencies and gave the plant operators more tasks and plenty to think about while they were trying to control the levels manually.
“The guys shouldn’t have that responsibility,” he says.
A light bulb moment
Scott Curran found a solution to the problem, when he was presented with Grundfos iSOLUTIONS, where pumps, sensors and control systems are connected and work together.
“I knew about controls like this from other applications, but when I was told it was fit for a boiler, it was a light bulb moment for me,” he says.
Subsequently, an intelligent Grundfos CRIE pump with built-in variable speed control has replaced a fixed-speed Grundfos CR pump, and now automatically controls the level of water in the steam boiler. The new pump is also able to activate a bypass valve when needed to ensure safe and efficient boiler operation.
“The number of improvements generated from such a small change is very impressive,” Scott Curran says. He refers to previous issues related to flooding and cooling down the boiler due to lack of level control. These issues have now been eliminated.
“This leads to energy savings and better steam quality. We’re experiencing energy savings of 40 to 60 per cent based on that one pump alone”, he concludes.