About the site
Landlogical is an independently owned and managed company that provides creative, practical, and cost-effective solutions and services for landowners and the construction industry.
Recently the company has invested in a washplant for their new Pasture House Farm Quarry at Thorney, Peterborough. Originally used as agricultural farmland the 53ha site has been turned into production as a sand and gravel quarry. This followed a geological investigation in 2014 which revealed mineral reserves of 3.7 million tonnes that would be suitable for a wide range of concrete and construction uses with all the processed material graded and tested to BS EN 12620 for concrete production which will be supplied to local companies, concrete plants and general builders.
On exhaustion of the mineral reserves the farm will then be restored back to agricultural use.
After researching the market for a wash plant and following site visits and consultation the Land Logical team selected a Terex® Wash Plant based on a Twin Compact Fines Master FM 120 C and a PS 120R Powerscrub which has been supplied by the English and Welsh dealer for Terex® Washing Systems (TWS) – DUO Equipment (part of DUO Group Holdings). As an industry leading supplier of innovative wash plants DUO have an outstanding pedigree in the marketplace for innovative solutions, customer support and expertise in the field to meet customers’ individual needs.
The Sand & Gravel Plant
The fully electric plant is required to produce 350,000 t/annum on a required feed rate of 170tph based on an approximate silt content of 5% providing two sands and four aggregates – 10mm/20mm/40mm/+40mm.
The plant is fed with a variable as-dug material into a 12m³ – H12 heavy-duty hopper with a remote-control hydraulic tipping grid. Material is then fed via a main feed conveyor onto a 4.9 x 1.5m double-deck rinsing screen which utilizes individually controlled spray bars on each deck which are fitted with polyurethane modular media.
Acting as a protection deck the top deck removes any rejects (+40mm), with the bottom deck providing the feed to the Fines Master 120C to produce the two required sands which are stockpiled by radial conveyors.
Twin Compact Fines Master FM 120 C
A static sand recovery unit on one chassis, the FM 120C is designed to process up to 120tph and features twin hydro cyclones – one G4 500 for sharp sand and one G4 375 for soft sand with two pumps; a 200/150 rubber lined Linatex pump for sharp sand and a 150/125 for soft sand.
A 4.3m x 1.8m high frequency dewatering screen fitted with polyurethane screen modules reduces residual water content in the final products to 10–15%.
A specially designed rubber-lined underflow box allows blending to take place so that an acceptable coarse and fine sand ratio can be achieved. These sands are then delivered to separate radial conveyors and stockpiled.
PowerScrub™ PS120R Logwasher
Any aggregate and clay is then fed from the rinsing screen into the twin-shaft PowerScrub™ Logwasher where the material is scrubbed, with the clay and contaminants removed.
The PowerScrub™ Logwasher consists of a 6.5m angle adjustable hull fitted with twin rotating shafts fitted with 15mm Hardox® 500 abrasion resistant blades. The blades convey the material from the feed end of the scrub to the 4.9 x 1.5m sizing screen.
As the material travels through the hull the abrasive action of the aggregate as it collides with other aggregate (stone on stone) scrubs it clean and breaks up any clay conglomerates which are then floated off through the back of the PowerScrub™.
Any organics such as roots or plastics are also floated off to be dewatered over the PowerScrub™ 6 x 2 trash screen. Underflow from the trash screen is received in a catch box under the screen and then gravity fed to the sump tank under the hull.
Scrubbed aggregate then exits the main discharge of the PowerScrub™ PS120R Logwasher via a transfer conveyor onto a 4.9m x 1.5m sizing screen which splits the required products of 10mm, 20mm and 40mm aggregate which are then stockpiled by stone conveyors.
Cutting Edge Control System
The control system for the Pasture House Farm Quarry wash plant is stored in a centralized cabin on the site which is one of the options offered by DUO through TWS on all installations, alternatively the panel can be mounted onto the machine, all of which are pre-wired. This option exemplifies the flexibility of TWS and DUO to suit individual customer needs or preferences.