Terex Ecotec Screening Trommels Sort Bulk Sawmill Waste Fast
February 7, 2025
Scottish haulage and material handling specialists Boyd Brothers operate from their Corpach quayside near Fort William. The company undertakes logistics services on several ports around Scotland handling a variety of materials, delivering a service dedicated to ensuring their customer’s goods are shipped safely and in good time. One of their clients for material handling solutions is BSW Timber who operate a state of the art sawmill at Corpach.
Founded in 1848, in Earlston, Scotland, BSW Timber is now the largest sawmilling company in the UK. Currently operating in eleven manufacturing sites across the UK and Latvia, BSW Timber are large-scale producers of certified timber products for various industries and applications, including fencing, landscaping, decking, cladding, construction, joinery and pallet production.
The company currently produces over 250 million linear metres of material per annum manufacturing the highest quality certified products from C16 construction timber to innovative products like composite decking and acoustic fencing.
The company’s site at Corpach receives around 450,000m3 of material annually, producing over 250,000m3 of finished products from the incoming material. But what happens to the remaining 200,000m3? BSW grow-to-size, harvest to order, and replant to replenish using the whole of the log – even sawdust, shavings, chips and bark, which supply the pulp and paper, chipboard, horticultural sectors.
Sister company, BSW Energy, also makes use of our timber co-products, manufacturing clean, renewable wood fuel solutions to power everything from biomass plants to stoves and barbeques.
At Corpach, the sawmill residue is collected throughout the mill on a series of conveyors before it is discharged at the adjoining Boyd Brothers site.
The sawmill residue comes from the mill in a range of sizes from dust to 60mm chips and until recently, the material was handled by a pair of Doppstadt 620 screening trommels hired by Boyd Brothers. Whilst these two units managed the job, their output was far from what was required. With the company sending out much of the screened material on vessels from the adjacent dock, the Boyd Brothers team decided it was time to invest in a screening trommel capable of handling a larger volume of material allowing stockpiles to be built up of various grades of chip and dust prior to the arrival of the vessels. Having a stockpile would then allow the vessels, each with a capacity of around 6000 tonnes to be loaded more effectively and more often using the stockpiles already created.
With a requirement to handle up to 120t per hour, the market for high output, screening trommels is limited. One of the only companies with such large screening trommels in their portfolio is Molson Green, part of the Molson Equipment Group. Boyd Brothers quickly contacted Molson and during their initial conversations with David Sutherland and Mike Mackenzie, it was decided that one of the new Terex Ecotec Phoenix 3300 screening trommels would be an ideal solution to the company’s production issues.
The Terex Ecotec Phoenix 3300 is the largest screening trommel available within the Ecotec range with an operating weight of just over 37.5 tonnes. Sitting on a 3-axle chassis, the screening trommels are delivered using a fifth wheel mounting to connect it to a suitable tractor unit. With a travel length of just over 21m, the Phoenix 3300’s delivery through the tight and winding Scottish roads took some planning by the Molson team to ensure it arrived without a scratch and caused as little delay to the local traffic as possible.
Once on site and set up, a relatively quick and straightforward task, the screening trommel could be set to work. The 3300 is available with either a heavy duty tipping grid or double deck vibrating grid to feed material into the drum. Like most screening trommels, the Phoenix 3300 is available with a range of screening media to produce any given products. Boyd Brothers have chosen six different sections of woven mesh ranging from 13mm to 20mm to give two consistent products suitable for a variety of construction product manufacture and horticultural uses. Depending on the media used, the screening trommels can quickly be reconfigured to work effectively with heavy construction and demolition waste or in the production of high quality composts.
The design of the screening trommel uses a high capacity, 7.8m3 hopper to receive the material. Mounted at one end of the heavy duty chassis, the hopper gradually feeds the material into the 2.32m diameter drum via a variable speed belt feeder. The material is sent into the 9.32m long drum which has been fitted with a variety of woven mesh which gradually segregates the material into two grades. The -15 grade passes through the mesh and onto a 1200mm wide discharge conveyor passing it back through to the hopper side of the machine. The 180° swivel fines conveyor can eject material to a maximum height of almost 6m allowing it to generate large uniform stockpiles leaving the wheel loader to concentrate on loading duties.
The large capacity drum in the screening trommel is driven by a powerful four wheel drive system with high performance friction grip wheels and allows the operator to run the drum in either direction. To ensure no chips stick and block the mesh, a series of nylon brushes stretch the length of the drum ensuring the mesh is always clean. The large chips pass out of the drum onto the 1200mm wide outfeed conveyor. Like the fines conveyor, this one is capable of being remote controlled and with variable speed control, the operator can create a pile of material exceeding 4m.
Power to the screening trommel comes from a Caterpillar StageV diesel which combines with powerful hydraulics and auto feeder speed control to guarantee the machine is always working at its optimum level.
With such a high output, Boyd Brothers have employed a pair of wheeled loaders to handle the input and output of products. The smaller machine with a 6m3 bucket spends most of its time loading the Phoenix whilst a larger machine with 8m3 bucket handles the screened material and also the loading of Boyd brother’s high capacity ejector trailer which ferries the material from the production area to the quayside.
‘We have been very pleased with the performance of the Phoenix since it arrived.’ BSW Group’s Gary Isherwood commented. ‘We have reduced our cost per cube to screen the material whilst massively increasing the output with a better product. Molson have been a great company to deal with delivering the product quickly and efficiently and giving us the ability to exceed both our and our customer’s expectations.’
