PECM Issue 23 2016 - Page 48

New SCADA System Brings Efficiency And Flexibility To Scottish Malting Barley Plant ffective site-wide energy management is a key function of the new control system which is being used to synchronise heat systems that include new biomass boilers. E A grain drying and storage facility that supplies some of Scotland's leading distilleries has installed a new Movicon SCADA (supervisory control and data acquisition) system from Products4Automation (P4A) to consolidate series of plant upgrades and expansions. The new software is providing control and visualisation for product movement, processing and storage, including the integration of biomass boilers and heat recovery systems. Highland Grains Ltd is an agricultural cooperative, owned by its 89 members, which dries, conditions and stores malting barley and other crops. It primarily supplies the Scotch whisky distilling industry, but also exports high quality grain to other countries. 48 PECM Issue 23 Based just north of Inverness, Highland Grains was founded in 1978 with a capacity to handle 4,400 tonnes of barley a year. Steady expansion has seen its annual throughput grow to over 40,000 tonnes. Today the plant consists of five continuous flow dryers, seven wet and fifteen dry storage silos (ranging from 250 tonnes to 2,300 tonnes) and two warehouse-like flat stores of 7,500 tonnes each. Committed to constant development, the site also includes innovations such as heat recovery on its drying systems, power synchronisation and biomass boilers. The facilities were always automated, and the control system and software were frequently expanded to meet new requirements and accommodate new equipment. The control system has been maintained and developed over many years by specialist local firm Coldcurve Ltd, which most recently was commissioned to replace the existing much-extended control system with an efficient state of the art one. The project was lead by Coldcurve engineer Daniel Castle, who explains that although the site's operations are relatively complicated, a simple system architecture was achieved: "Lorries are constantly delivering grain from the growers, while others collect dried malting barley for the distilleries – it's a 24/7 process at busy times, plus there are several different drying processes. There are also a number of subsidiary processes to control, such as incoming and outgoing weighbridges, boiler operations and heat recovery for energy efficiency." The whole site is now controlled from a single, powerful PLC supporting 29 separate I/O cards.