BIM has acquired a mobile shredding unit, funded under the European Maritime and Fisheries Fund, to process plastic wastes from the fishing and aquaculture industries. The shredder allows items including trawl nets, salmon cage nets, mussel floats and oyster bags, to be shredded and compacted for easier transportation, storage and recycling.

The custom-built unit from Ulster Shredders Ltd, Magherafelt, Co Derry, was used initially to shred old mussel ‘barrel’ floats. Stripped-down, fishing nets were then collected and shredded from four ports in the south east and east.

“We’re delighted to be involved in this high-profile initiative. We had to make some significant modifications to the U-45 shredder to contribute to its mobility. Once it is positioned on the quayside, it is powered by a generator on the low loader which makes the machine a ‘stand-alone’ unit,” explains Elliott Martin, managing director.

The shredder and the generator can be transported on a flatbed 4-axle truck with a remote controlled 55 tonne/m telescopic crane. The crane enables on-site set up and the moving of bagged material to a close storage point.

Shredding mussel floats on Rosroe Pier, Killary Harbour. Patrick Faherty (mussel farmer), John Bell (GreenMarine), Pat Lydon (mussel farmer), Myles Mulligan (BIM), Michael Murphy (Green Marine), Mary Hannan (BIM) and back right, Killian Murphy (Green Marine)

Just under ten tonnes of nets were processed with steel from the warps being separated and sent for recycling. Five bags of shredded nets were collected, yielding approximately 2.5 t of recyclable plastic material.

Each port has a different arrangement for recycling but usually half of the proceeds are donated to the RNLI.

The shredder accepts a range of hard and soft plastic wastes such as polyethylene netting, most hard floats, polypropylene ropes, fish boxes, nylon cage net frames, hard plastic equipment, plastic boats, mussel barrel floats and oyster bags.

For example, in the case of a typical whitefish trawl, once the reusable floats and other accessories are removed, the netting can then be ‘stripped’ off the head ropes, footropes and where the selvedge has been completed with nylon or polyester twines.

The resulting clumps of clean mesh of a manageable weight are then stored in an on-board receptacle or in the storage bags supplied for landing to a storage area ashore.

Recycling history

Interest in the recycling of industry plastics began in 2003 when BIM conducted an environmental awareness campaign. In 2006 BIM, along with the then DCMNR and PETLON UK Recycling Group, began a state-funded project in Dunmore East to develop a system whereby monofilament waste netting was collected, baled and eventually recycled.

Further progress took place in 2007 with a more permanent and economical transfer centre: Green Marine Recycling Transfer Facility in Tramore, Co. Waterford.

To date, circa 500,000kg of nylon waste material has been collected from Irish and visiting fleets.

In 2012 BIM, Green Marine Recycling and GEOLINE Lining Systems Ireland, joined forces with Centriforce to develop a pilot project for recycling polyethylene nets and related items such as rope and twine.

In 2016 the large quantities of stored polyethylene-based trawls and industry equipment was targeted in a collective project coordinated by BIM along with the Department of Agriculture, Food & the Marine, Donegal County Council, Wexford County Council and the Clogherhead Development Group.

187 metric tonnes of bulk polyethylene-based gears and equipment was processed, extracting approximately 74,000kg of marketable polyethylene feedstock.

To address logistical difficulties and transport costs, BIM explored having a dedicated mobile shredder to increase the amount of material per cubic metre contributing to leaner logistics. Similar efforts were made into assessing the polymer continent of the packaging and galley wastes with consideration given to the use of high density polypropylene mini balers, suitable for operation in marine environments, to compact the polymer waste streams onboard fishing vessels.

This work now forms part of the Clean Oceans Initiative launched by Minister Creed in January at Union Hall, Co Cork.

Myles Mulligan, BIM