There were 6 X Babcock and Wilcox chain grate boilers with spreader stokers in Boiler Houses 1 & 2 plus just four boilers in Boiler House 3. During commissioning it was discovered that enough steam was generated by the 14 boilers to achieve the required load. Each Boiler had it’s own control panel and produced 240,000 lb/hr of steam at 65.5 bar and 496 degC .
The spreader stokers were something new and were like a missing link between chain grate and a PF firing. There were eight Spreader Stokers per boiler and they threw the coal into the boiler to be partly burned in suspension and partly burned on the grate. The grates ran from the back towards the front unlike standard chain grate boilers which ran front to back.
Spreader stokers required a lot of attention to maintain good combustion and a lot of maintenance to keep the rotor and pusher plates in good condition. (see diagrams in technical section) The biggest problem was keeping an even bed of coal on the grate. If a problem with a stoker led to a gap in the coal bed on the grate then the combustion air would rush through that hole and starve the rest of the fire of air. This would result in incomplete combustion leading to a black stack. As a result of this Staythorpe `A’ was one of the first stations to have TV monitoring in the control room for their three chimneys.
