Oct 27 2006
A report published this week addresses the sustainable use of all resources for the production of aggregates. This is of great importance, as some 280 million tonnes of construction aggregates are consumed each year in the UK and optimising resource use and minimising waste is an essential element of sustainable construction.
Using data from a new and unique economic model, the report, entitled ‘The sustainable use of resources for the production of aggregates in England’ reveals how the use of recycled and secondary aggregates (RSA) is going to increase, and the impact this will have on primary aggregate production and sales.
Produced by WRAP (the Waste & Resources Action Programme), the economic model predicts future trends and identifies the different influences these will have on the sustainable use of all resources for aggregates.
The model is based on a study, which focused on the West Midlands area, taking into consideration four main variables: supply (resource availability), costs (aggregate production and haulage), market price (product) and demand. To achieve the final results, it was necessary to identify, understand and translate the interrelationships between these market variables.
The model identifies several significant changes that could have an industry-wide impact, including:
- an increase in the market share of RSA from approximately 25% to 30% by 2011;
- RSA use for higher value applications such as aggregates for concrete and asphalt;
- an increase in demand on crushed rock quarries for low grade fills and scalpings;
- a fall in market share in higher value crushed rock, sand and gravel products;
- the sustainable use of primary resources will require a change of practice and processing to meet market demand, optimise average selling price and minimise excess stock;
- a need to develop crushed rock processes to minimise the production of dust;
- continuing investment in washing plant for excavation waste from construction will result in the production of a range of higher value aggregates; and
- the growth of the sustainable use of recycled and secondary resources for aggregates in the West Midlands study area is finite and is expected to reach an optimum level around 2011.
The report shows that over recent years the range of recycled aggregate products has grown and expanded from low performance fills to capping and sub base. Investment by recycled aggregate producers is further increasing this quality product range into materials for concrete and even decorative aggregates.
As the range and tonnage of recycled aggregates grows, it will have an increasing impact on primary aggregates and this will prompt a reassessment of production processes and products.
Many crushed rock quarries already have a problem with excess production of dust, and the model predicts this will increase. In some quarries this issue may be resolved by investment in washing plant, however the bigger challenge is to develop plant that minimises this dust production.
"By looking at the total aggregate market, we can identify potential inefficiencies as the market changes and provide technical advice and possibly grant support to reduce any potential waste arising and optimise resource use," comments John Barritt, WRAP’s Aggregates Technical Advisor. "WRAP will be looking to work together with aggregate producers to anticipate these trends and assist in the sustainable use of all resources for the production of aggregates."
The economic model has provided an interesting insight into how the market will develop and has already been welcomed by mineral planners at the Department for Communities and Local Government and the Quarry Products Association to assist with planning future aggregate demands.