Limescale control slashes maintenance costs
The cost of installing equipment to control limescale in spray nozzles was recovered in just three months at Imperial Tobacco in Nottingham.
Maintenance costs and downtime of a rehydrating unit at the Nottingham plant of Imperial Tobacco have been reduced following the installation of a Kal-Guard+ scale inhibitor from Watermatic. A payback of less than four months was achieved. Before installing the 35 mm Kal-Guard+ unit on the water supply, the company needed to spend around three hours a week to remove scale from the spray nozzles manually, at a cost of around £30 an hour. Plant downtime added to the costs. The gradual scaling up of the nozzles changed the spray pattern, so regular descaling was necessary to maintain quality control. Alan Whitelock of Imperial Tobacco explains, ‘Since installing the unit, there is now only an occasional slight residue of soft limescale that is easily wiped away during the routine cleaning of the machine.’ This scale inhibitor is based on a zinc anode electrolytic design with electronic controls to match zinc levels to the hardness of the water. Tests at Cranfield University have shown that Kal-Guard+ reduces limescale on heating surfaces by up to 80%. A status monitor confirms that the electrolytic cell is working, so that maintenance staff can check operation.