RockTron offer cheaper OPC replacement

TWO newly launched products are promising cement users a 50% CEM 1 replacement material for around half the price of ordinary Portland cement (OPC) and around a quarter of the price of ground granulated blast-furnace slag (ggbs).

The new pulverized fuel ash (PFA) derived alumino-silicate products, called Alpha (a powder) and Delta (a filter cake), are also offering UK ready-mixed concrete suppliers a ‘greener’ alternative to traditional replacement products.

Produced by RockTron and launched in June 2009, Alpha and Delta are created by a special process from fresh or stockpiled fly ash, providing a potential solution to the 100 million tonnes of former power station feedstock currently sitting in landfills across the UK.

With a loss-on-ignition (LOI) factor of less than 2%, both products are said to offer substitution rates with OPC of 50–55%. RockTron are also testing an 80% replacement rate.

According to Peter Crofts of RockTron, not only are the materials cheaper to buy than traditional replacement products, they are also more environmentally friendly. ‘For every 500,000 tonnes of our product that replaces OPC, up to 400,000 tonnes of CO2 can be saved in the UK,’ he said.

RockTron say they are currently in discussions with all major concrete producers but are not seeking exclusivity; smaller concrete and precast manufacturers will have equal access to the new products.

The company currently has one UK processing plant – an 800,000-tonnes-per-year facility at Fiddler’s Ferry, near Widnes, in Cheshire. However, plans are being made for a second plant at Gale Common, near Doncaster, as well as further expansion in the future.