A REVOLUTIONARY sugarbased coating for road salt that claims to reduce chlorideinduced steel corrosion by more than 80% is on trial on the M4.
Safecote, a blend of organic and inorganic compounds derived from sugarbeet or molasses processing, is sprayed on to rock salt as it leaves the crusher.
The trials are being organised by the Highways Agency's Area 2 managing agent Atkins and are said to show that 30% less salt is needed if the coating is applied.
'The sugar removes oxygen from the water in the concrete pores, and without water rust can't form, ' explained developer United Molasses' technical manager John Higginbotham. 'It also inhibits movement of the chloride ions to the steel.'
Initially the coating reduces dusting and prevents clumping of the 6mm nominal salt particles. 'This gives a much more economical spread pattern, ' he said.
The trials will be reviewed at the end of April.