Recycling rock salt and grit could be a money-spinner says Peter Craven of CDEnviro
The effects of the European Union’s Landfill Directive together with the annual increase in Landfill Tax have significantly increased the cost of disposal of gully waste. In the UK this is approximately £50 (€58.8)/tonne but it will rise to £80 (€94)/tonne in 2014 in the UK although other parts of Europe it may differ. As a consequence it has increased the operating costs for companies providing gully emptying services. The effects have been felt not only in the UK but also by other countries in the EU.
While the revised Waste Framework Directive (rWFD) details that all EU Member States recycle a minimum of 70% of waste generated from construction, demolition and excavated material (CD&E) by the year 2020, the UK is in the Top Ten countries in Europe for recycling CD&E waste. However in terms of recycling road sweepings and gully waste, Europe is leading the way and the UK should take a few lessons from its European cousins.
In the UK each winter over 2 million tonnes of rock salt and grit is spread onto the road networks at a cost of over £150 million (€176.5 million) each year. With this material eventually going to landfill the irony is that in the following year the
Many European countries currently recycle road grit to remix with salt for spreading on the highways. In order for the UK to stay in the Top Ten of recycling countries in Europe, road grit and gully waste could be the next initiative. The technology is available now to recoup what is currently a wasted resource, and such actions will protect stocks of virgin aggregates.
Road sweepings comprise mainly grit from road dressings, small grade aggregate, organic material, ferrous products and a small amount of hydro carbons. However, up to 98% of the material is capable of being processed and reclaimed.
The saline constituent of the rock salt is dissolved and washed out but the grit and the aggregate material that remains is reclaimable.
The reclaimed grit can be remixed with rock salt and reused, and the larger aggregates can be reclaimed and used for other applications.
Sand or grit forms 50% of the overall material recycled, with 40% being larger aggregate and the organic material, constituting the remaining 10%, can be composted.
Gully waste typically comprises small stones, sand, gravel, grit, ferrous material, paper litter and hydro carbon with organic matter mixed in. However, the main constituent of gully waste, even when the free water has been allowed to drain off is water.
Water constitutes up to 60% of the total volume of gully waste which seems a ludicrous product to be sending to landfill.
However, the UK is picking up the pace. In January 2012 Warwickshire County Council in England installed a recycling facility for road sweepings and gully waste in the city of Wolverhampton, West Midlands, working with six waste disposal authorities in the region.
Like many local authorities, Warwickshire County Council was sending its road sweepings and gully waste to landfill.
CDEnviro, the environmental recycling arm of
During the project over 300,000tonnes of material will be diverted from landfill, creating in excess of £10 million (€11.8 million) cashable efficiency savings over seven years, with the projected increase of the overall material recycled being in excess of 3%.
“We have seen great uptake in the concept of road grit and gully waste recycling in the UK and through our partners in Europe,” says Peter Craven from
“With the processing of this material being charged at approximately 50% of the cost to landfill it makes economic sense without even taking into consideration the recycling of the processed material. This technology has led to a reduction in waste going to landfill of up to 75%, while producing a high value product. That’s got to be good business sense.”
