According to a new Seafish project which specifically looked at the feasibility of using shell waste in aggregates, it is possible to reduce costs and in the right circumstances even generate a modest income from some shell fish waste.
Michaela Archer, Seafish Project Manager said: “Disposing of shell waste is a major financial burden on the shellfish industry. Disposal costs can be as high as £150.00 per tonne so the industry is constantly looking at ways to reduce the cost of disposal, and even potentially generate an income from this waste.
“Shell is not well utilised in the UK with only a small proportion treated and sold as by-product. Most processors rely on disposal outlets, but our estimate is that the UK produces around 43,000 t/year of shell which could be practically used by the construction and building industry, in either a free-flowing or bound format, as a constituent part of the aggregate used in certain applications.”
The project focused on using free of flesh (clean) whelk, mussel, cockle, oyster, crab, and king and queen scallop shells, and looked at simple, relatively low cost bulk aggregate applications to identify how suitable they were.
Seafish funded the work through the Industry Project Fund and involved a number of industry partners and seafood processors. The project looked at costs, market availability, the extent of shell treatment required and licensing requirements. The type of shell produced, the extent of shell-cleaning required and the geographical proximity to good, local markets were found to all be crucial to the viability of deriving value from shell.
“This is a step in the right direction,” said Michaela. “Shellfish processors want simple, local, cost-effective outlets for shell, and aggregates could potentially be a viable market. The project has also flagged up to the aggregate sector that shell could be an alternative raw material.
“Supplying shell to the aggregates market can reduce disposal costs. Although in some cases the supply of shell may only provide a cost-neutral solution for processors, that in itself is a benefit. In other cases an economic return and small profit is feasible. But it does require significant effort on the part of seafood processors to realise the benefits.”
The report entitled ‘Shell Waste in Aggregates’ was published in April 2008, and can be downloaded from the Seafish website
