ICI drives for greater efficiency
15 Jan 2000
The installation of variable-speed drives has given a significant boost to the efficiency of ICI Chemicals and Polymers' brine purification plant at Lostock in Cheshire. The units have also reduced the plant's maintenance costs, according to Alstom Drives and Controls, which supplied the inverters.
The plant supplies purified brine to one of ICI's major customers, Salt Union in Runcorn, but the material is pumped 15 miles to a reservoir, where it is stored until needed. The two pumps which perform this operation were, until recently, fixed-speed units running flat-out at all times, which lead to almost continual failures in the pump bearings and energy wastage.
ICI decided to remedy this situation by fitting ALSPA GD3282E variable speed drives from Alstom Drives & Controls (known as Cegelec until recently) to each pump. The pump speed can be altered according to the output of a level controller. This matches the pump's output to the required flow-rate. Moreover, it starts up the pumps at a controlled rate, cushioning the system from mechanical shocks.
`Now that the pump speed is controlled far more accurately, energy consumption, maintenance costs and downtime have all been reduced,' comments Altsom.
