AggreSandsystem from Terex
Terex Washing Systems (TWS) is to unveil a new innovative washing system that combines aggregate washing and screening with sand processing on a modular chassis.

AggreSandsystem brings together tried and trusted Terex Washing Systems components in an innovative modular design, setting itself apart from other washing systems in the marketplace. gap in the market for such a washing evolution was identified following extensive research, part of which was conducted at the Terex Washing Systems first ever product development forums. This involved TWS engineers and sales technicians working with the global distributor network to formulate the concept. Central to the development of the new plant was a modular design, pre-wired and pre-plumbed making it quick and easy to set-up and easy to maintain. The plant also includes a range of other innovative features and designs.

Sean Loughran, Director of TWS commented, "The AggreSandsystem will represent the epitome of washing in the marketplace and is a combination of significant enhancements and design changes to existing products as well as the introduction of new pioneering ideas. In our ongoing efforts to meet and exceed customer expectations, the AggreSandsystem will enable TWS customers to wash a wide range of materials at a high specification and produce up to five products."

Key features

H 12 hopper - TWS designed a new modular hopper feeder with 12 cu m capacity in keeping with ever increasing loading shovel sizes in today's modern quarries and sand pits. The H12 is available with an automatic tipping grid and a 12' two deck vibrating grid complete with variable speed belt feeder, all controlled from the main operator interface and radio control unit.

Feed conveyor - The wide feed conveyor has a direct drive electric motor and gearbox arrangement and will work at a 19o angle when feeding the AggreSandsystem. The inclined feed conveyor features an innovative sealed wash box at the discharge point to give material a pre-rinse to pre-condition for screening. The innovative design eliminates splashing at this point and produces an even distribution of material to the full width of the rinsing screen thus utilising the full screening area.

165R-3 rinsing screen - TWS opted for the highly efficient 165R-3 (three deck, two bearing) rinsing screen. The screen's riveted construction reduces the stress associated with welded construction methods. TWS engineers designed this in such a way to isolate the spray bars from all vibration, utilising high quality rubber gators on the mid and bottom decks. Top deck rubber extensions also prevent overspill or splashing from the top deck screen. The 165R-3 gives a true 80 sq ft (7.54 sq m) of screening area on all three decks. Each deck has eight individually controlled spray bars fitted with polyurethane fan type spray nozzles. An advanced rolling chute arrangement gives the ability to blend top deck and mid-deck overflows as well as mid-deck and bottom deck overflows which will prove very useful in construction and demolition recycling applications. The screen is designed to receive standard polyurethane modular screens (woven wire screens option also available) on all decks.

Sump tank - The large capacity split sump tank receives the rinsed fines from the bottom deck screen into either a course or fine compartment. The course side of the tank has a built-in float system to help equalise the levels in both tanks and prevent overflowing. Large inspection doors are included in both tanks as well as butterfly valve drains on both sides. The tank is also fitted with anti-turbulence plates and a pump protection system.

Centrifugal slurry pumps - Two centrifugal slurry pumps (Course & Fine) are used to pump material from both sides of the sump tank into two hydrocyclones. The hydrocyclones remove silts and clay (material below 63 micron) which are sent to the water treatment plant. The heavier material (above 63 micron) exits the bottom of the hydrocyclones into a rubberlined box where blending can take place if required.

125 dewatering screen - The underflow from the hydrocyclones transfers onto a dewatering screen via a discharge box which equally distributes the material across the screen to increase the dewatering screen area. Both materials are dewatered over a 500 micron polyurethane screen to produce two instantly salable grades of sand. The high energy dewatering screen is fitted with two high efficiency counter rotating vibratory motors which remove capillary water to produce two dewatered sands. The rubber lined catch box under the dewatering screen carries the underflow back to the tank for recirculation through the cyclones. Integrated conveyors - The AggreSandsystem has the option of five conveyors, three aggregate and two sand. The 650 mm wide conveyors are powered by direct drive electric motors and gearbox arrangements. The 9.3m long conveyors are angled at optimum height for excellent production. The two conveyors have an innovative automated radial wheel drive system that increases stock piling capacity to an amazing 350m3. The conveyors are fitted with high quality teardrop polyurethane scrapers. The aggregate oversize conveyor has a novel feature whereby it can be placed on either side of the machine in accordance with the customers site set-up/preference. The 4m stock pile height of these conveyors make them ideal for producing generous stock piles or feeding other equipment within the Terexproduct range.

Accessible service areas - Maintenance and access was of critical importance during the design process of the AggreSandsystem and this has been achieved through a number of advanced features. There are 600mm wide access platforms on both sides of the machine. This allows easy access to both the rinsing and dewatering screens. All walkways and handrails are galvanised as standard with curved ends and expanded metal floors. The centrifugal slurry pumps are mounted on roll in - roll out tables for ease of access and maintenance. The main feed conveyor section which travels over the aggregate screen is hinged so that it can be raised to allow greater screen access. The rinsing screen has a roll away chute to also allow for easy access to all screen decks. The plant is also fitted with a high pressure retractable wash down hose. If required the spray bars can be easily removed for maintenance purposes. The pumps on the plant are fitted with drains for drainage in frosty conditions to virtually eliminate downtime. The AggreSandsystem is supplied with integrated prewired 4 x 500 W metal halide flood lights controlled via photocell and mounted on winch controlled hinged poles for ease of maintenance.

Cutting edge control system - TWS has developed an advanced and cutting edge user-friendly control system. The AggreSandsystem will give operators levels of automation and control not previously available on wash plants. TWS has utilised PLC technology which has already been field proven within the wider Terex crushing and screening plants. The control system will provide measurement and control in terms of belt speed, water pressure, pump pressures, etc. This will include full radio control of all critical functions such as auto start/stop, feeder start/stop and speed control. Full telemetry is supplied as an option where all data is sent to the plant owner remotely such as belt tonnages, alarm conditions, run times, etc.