Control and automation of the Manchester to Liverpool sludge pipeline of the North West Water Authority. I

The sludge pipeline scheme, enabling the transfer of the Authority´s sludge shipping operation to the new Liverpool Sewage Treatment Works, consists of five pumping stations operating in series, with variable speed control to suit the varying hydraulic requirements. It is an example of a fully integrated automation system in the water industry, using communicating PLCs. The author discusses the design of the pipeline and then goes on to describe the power systems for each of the fine pumping stations and the variable speed drives using synchronous motors and static thyristor convertors