Owned and operated by CEMEX UK the Swinderby site is located near Witham St Hughs, Lincoln and was originally used as a WW11 airbase; with bomber operations from 1940 the airfield saw constant use by the RAF up until 1993.
A greenfield site:
Development started approximately 2 ½ years ago on a new greenfield site within the environs of the airfield utilizing the remaining landing strip as the haul road. This was then followed by the concrete pads for the plant and the weighbridge and the development of water lagoons.
With the infrastructure complete CEMEX UK researched the market and following a successful tender Duo Equipment were then selected to supply a new wash plant based on the TEREX® Washing Systems Aggresand™.
As the English and Welsh dealer for Terex Washing Systems (TWS) Duo can offer innovative wash plants and water management solutions. This demonstrates TWS commitment to providing outstanding products, customer support and expertise in the field to meet customers’ individual needs.
The sand & gravel plant:
Duo based their plant design on the latest TWS technology incorporating the TEREX® AggreSand™ 165 modular wash plant which is pre-wired and pre-plumbed and is an easily installed modular concept that facilitates quick installation; a combination that is very appealing in terms of access, serviceability and modularity.
The all electric plant includes a rinsing screen, sand plant, lignite removal plant, stockpilers and all associated pipework and electrics on one modular chassis, with a PowerScrub™ 120R logwasher, sizing screen and stockpilers completing the specification.
Wayne Strevens – Operations Manager, commented, “It’s a very neat compact plant incorporating an in-line system with ‘as raised’ ballast being fed by loading shovel into the feed hopper. We’re generally very pleased with what is a reasonably simple and effective set-up.”
Capable of operating at 250tph the plant consists of a bespoke feed system which is fed by wheel loader via a feed hopper incorporating a remote-control tipping grid. Material is then delivered onto the main inclined feed conveyor which is driven by two 11Kw electric motors with Bonfiglioli® gearboxes mounted on either side of the drive drum. This set up not only provides balance to the conveyor but also gives enhanced torque characteristics.
The AggreSand™ 165:
The AggreSand™ 165 at Swinderby incorporates a 16 x 5 double-deck rinsing screen which utilizes eight individually controlled spray bars on each deck. The two-bearing screen is fitted with polyurethane modular media on both decks. The top deck acts as a protection deck removing any material above 40mm which is then fed via an inclined conveyor to a cone crusher which then recirculates crushed material via conveyor back onto the top deck of the rinsing screen. The bottom deck provides the feed to produce the required concrete sand. All chute-work on the AggreSand™ 165 employs the now well tested dead-box system which results in rock on rock set-up which is proving to give excellent wear properties.
Currently the AggreSand™ 165 sand plant consists of a 250/200 Linatex centrifugal pump driven by a 55Kw motor. Two G4-660mm cyclones produce an in specification concrete sand which is fed via the TAK Lignite Hydro Classifier prior to been delivered to a radial conveyor and stockpiled. Any material between 5mm and 40mm is then fed by inclined conveyor to the PowerScrub™ 120R for scrubbing and removal of clay conglomerates.
The plant at Swinderby incorporates a TAK Lignite Hydro Classifier which is a specialised sand classification tool which classifies the sand according to the weight of the particles. With the lignite being a third of the weight of sand it singles out the lighter grains of lignite and floats them out over the top leaving the sand grains behind. Essentially, it’s a unit that is designed for classification of glass sands which have very tight tolerances, therefore by moving the set point in the classifier vessel either up, or down you can adjust to a very refined measure of how much bottom end you have in the sand.
At Swinderby the sand is screened through the main washing screen of the AggreSand™ 165 and then fed to the main sand sump and then up into the TAK via the hydro cyclone. This then concentrates the flow ensuring a flow of about 65% solids is established (which means that within that vessel, the upstream current – to classify the sands and float off the lighter particles).
At the front-end the sand screen feeds the sand through into a sump which pumps it up into the hydro cyclone which is mounted above the TAK. The hydro cyclone then removes the ultra-fine particles, taking them from the top and then feeds a concentration of sand into the TAK. When the sand settles in the TAK a clean water upstream current is introduced from the bottom and then by moving the set point, up or down you can then control precisely what the grading is at the bottom end of the sand and how much you float off.
The PowerScrub™ 120R:
The PowerScrub™ 120R consists of a 6.5m 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 8 x 4 aggregate rinsing/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 go straight to waste.
Scrubbed aggregate exits the main discharge of the PowerScrub™120R to an 8x4 part-rinsing screen. The initial section of this screen is fitted with spray bars to rinse off any sand or grit residues produced during scrubbing. The rinsed grit is captured in a partial catch box under the screen and goes straight to waste.
Material is then fed via transfer conveyor onto a 16 x 5 double-deck dry screen to produce 4-20mm and 4-10mm, clean aggregate, both of which are delivered to stockpiles.
Cutting Edge Control System:
The control system for this specific AggreSand™ wash plant is stored in a centralized cabin on the site which is one of the options offered by Duo through TWS on all AggreSand™ 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 and the AggreSand™ concept to suit individual customer needs or preferences.
TWS provides cohesive solutions for all material and mineral washing needs. Focussing solely on providing solutions to quarry, aggregate, mining and C&D recycling industries it is dedicated in providing reliable, high quality and very productive equipment.
This is achieved through a broad product portfolio which offers modular, mobile and static wash plants with the ability to work in many applications. Meeting individual materials and mineral washing needs to achieve today’s stringent specifications of clean material is at the top of the agenda.
The TWS portfolio offers excellent reliability, ease of transport and fast onsite installation, which are key features of the innovative washing solutions – the AggreSand™ and AggreScrub™ Range.