07 March 2008
Safeguarding delivery of the granite-based stone found at the 147-year-old Poortown Quarry, Isle of Man, UK for the Works Division of the island's Department of Transport has seen UK£ 7,6 million (€ 10 million) spent extending and modernising the site.
The two new Metso Minerals Lokotrack LT200HP mobile crushing plants and four mobile screens now crush and sort blasted rock into 28, 20, 14, 10, and 6 mm aggregate. Most of the stone is used to build and maintain the island's road system, with the 28 mm product used for the base course. Wearing courses require 10 and 6 mm aggregate. The 6 mm product is also used for footpaths.
Raw stone is loaded into the tracked Lokotrack LT105, which can be moved up to the blast face to process the rock before feeding it to the secondary Lokotrack LT200HP. This is then passed via conveyor belt to a Lokotrack ST348 mobile screen to remove >20 mm stone.
Material is then fed through a Lokotrack LT200HP and ST352 mobile screen, which produces 10, 6 mm or dust. Another ST348 produces 28, 20 or 14 mm aggregate, which can be added to bitumen in the quarry's coating plant.