Recycling on screen: what comes next?
By Lindsay Gale01 May 2008
When you think crushing, it is almost automatic to follow up with screening. D&Ri reports on some of the latest additions to the screening sector and illustrates the use of this type of mobile equipment
As the push to increase recycling rates in the demolition and C&D waste sectors, it is axiomatic that before and after the crushing operation, the materials that result need to be segregated and separated to make products of uniform size and quality. This is driving the development of mobile screens, frequently by the same manufactures that produce mobile crushers.
In this article, we take a look at some of the latest additions to the mobile crusher product group, as well as report on some of the uses that this type of equipment is put to.
Screening is big business across the world in a number of applications, and that is certainly the case in North America. This region has seen a number of new machines make a recent appearance onto the market.
First is Astec Mobile Screens, who has unveiled a new ProSizer 2612V, a combined crushing and screening unit specifically for asphalt reclamation applications. Trailer mounted, it features a double deck PEP Vari-Vibe high frequency screen. Hydraulic screen angle adjustment and a rotary screen tensioning system allows the machine to meet the varying RAP application demands. A quick set up time of 15 minutes for the entire unit means that it can be easily moved from site to site.
Grasan meanwhile offers a similar ‘custom’ approach for its screening units as it does for its crushing equipment. All feature a high degree of mobility, rapid set up and a long service life with minimum maintenance, says the company.
Screen sizes range from compact 1.5 m (5 ft) by 4.3 m (14 ft) up to 2.5 m (8 ft) by 7.3 m (24 ft) and all feature self-erecting, all-hydraulic setup that allows a single operator to deploy the machine ready for use.
KPI-JCI, another member of the Astec group of companies has added a new Fasttrax screen model to its product range in the shape of the FT5162i. It is equipped with a 1.5 m (5 ft) by 4.9 m (16 ft) tow deck vibrating inclined screen and also features a 48 inch apron feeder, 48 inch oversize conveyor, two product conveyors and an under screen conveyor designed to be easily accessible for maintenance.
The two-deck screen features a modular bolt-in deck design to allow it to accommodate multi media options. These can be rapidly changed to suit the needs of the specific application. Setup is carried out using a hydraulic system quickly and safely, and while not mobile, the unit can be easily moved on standard low-boy trailers.
Where compact mobile screening is concerned, growth here is usually at the attachments end of the equipment spectrum, with many manufacturers offering screen attachments that fit on the end of a compact crushers output conveyor. One example is the screenbox available from Rockster for use with its R900 impact crusher. One such equipped unit is currently working near Zaragoza in Spain to clean limestone contaminated with black earth and clay for use as road surfacing on the regions forest roads. Crushing and cleaning the material on site has major cost saving implications for the contractor carrying out the work.
It is currently unusual for manufacturers to develop mobile compact screens that can be used with their mobile compact crushers, but Rubblemaster who has taken this step and launched the TS3600 double deck compact tracked unit. This machine has been designed to be used in conjunction with its largest crusher, the RM100 .
Again as is the case with utlracompact crushing attachments suitable for use on hydraulic excavators, there is a growth in demand for similar screening capabilities for small-scale screening applications, and there are a number of solutions out there.
UK based Dig A Crusher has added a range of screen attachments for hydraulic excavators to complement its line of Dig A Crusher branded Meccanica Breganzese crushing buckets. Three separate series of screening buckets will now be available under the Dig A Screen name.
The first of the is the four model S Series, each available in standard, heavy duty and mixing bucket variants, for 10-35 tonne excavators. The four-model R Series (rotating trommel) bucket is for machines from 13-35 tonnes, and the V Series (vibrating riddle) consists of three models for 13-30 tonne machines.
D&Ri understands that these screening buckets are manufactured by Rotar in the Netherlands and Remu in Finland, and are branded under similar arrangements to the MB crushing buckets.
The attachments will initially be available only in the UK, but Dig A Crusher managing director Sean Heron said that Dig A Crusher attachments have recently been sold into Africa and the Middle East, suggesting that the company’s ambitions are not restricted to the UK since its foundation in 2003.
Meanwhile, another UK based manufacturer, DigBits, offers its MultiScreen bucket suitable for use on excavators from 0.75 to 7.5 tonnes. These buckets, which are built to a heavy-duty standard to cope with work in hard materials, have interchangeable back plates that enable use on different types and grades of product. Normally, these are supplied with three interchangeable back plates; a solid (i.e. digging/loading) back plate; and two mesh screen backs with 25mm and 50mm apertures respectively.
But it is not just excavators that can sport screening attachments. Backhoe loaders have not been forgotten. Australian manufacturer Flip Screen has recently added a new BL30 backhoe model to its line-up of screening attachments. The company also offers screening units for skid steers, wheeled loaders and telehandlers, in addition to its range of mid-sized hydraulic excavators. Flip Screen sells its products through a dealer network around the world.No matter the size of your screening job, there is equipment available that should provide the required performance.