The Electronic Waste Company in the United Kingdom has announced that it is to carry out the first stage of recycling one of the worlds most pioneering and popular computer games consoles the Sony PlayStation. It has signed contracts with Sony Computer Entertainment Europe to shred and dispose of the plastic cases of the consoles an estimated 250 tonnes or 300,000 cases in the first year alone for Sony operations in Europe.

Routes for the recycled plastic have already been already identified as pens, chairs, etc. The Electronic Waste Company has significantly invested in new machinery, which can process a range of plastics and generate high-quality materials ready for the manufacture of new products. The machinery can process plastics ranging from thin films to the thickest of polyurethanes. The company will ensure 100 per cent reuse or recycle of this equipment; nothing collected or brought to the company will be sent to landfill. It is now developing processes to remove other recyclable components such as clips and foam from the PlayStation casings.

Source: www.mcvuk.com

Plastic Herverwerking Brabant BV (PHB), a Dutch plastic recycling firm, has become the first supplier in the world of a complete commercial altered-density-media system for separating the plastics in waste electrical and electronic equipment (WEEE). PHB is operating a WEEE recycling system with a capacity of 15 million kg/year, averaging about 1,195 kg/h of reclaimed material from 4,990 kg/h of waste input. The relatively small proportion of recaptured saleable material pays off because it includes about 10 per cent valuable metals mostly copper, but also gold. PHB builds commercial recycling machinery through another company called Envirotec BV.

The Envirotec line starts with shredded WEEE plastic with more than half contamination from non-ferrous metals, stones, polyurethane foam, glass, etc. The waste is fed into a box where a high-torque rotor with paddles turns at 3,000 rpm to beat the flakes against a screen cage, removing most of the surface dirt, sand, rocks and foam in seconds.

Flakes then go onto a large inclined tray with a grooved surface. Water sluices over the left half of the board, washing the plastic flakes down. Heavier metals stay in the grooves and move off to the right. The plastic flakes are then ground into 10 mm particles in a granulator, and sent to the first float/sink tank, which is filled with plain water. Polyethylene (PE) and polypropylene (PP) float off and are collected. Acrylonitrile butadiene styrene (ABS), polystyrene (PS) and flame-retardant (FR) materials sink, and are moved into another tank containing an aqueous solution of 1.035 g/cc density as well as three rotating drums with paddle vanes. PS floats in this tank and is collected, while ABS and FR materials sink. ABS and FR go into a third tank fitted with four drums having paddle vanes and filled with a water solution of 1.07 density. Here ABS floats and is collected, while FR materials sink.

This WEEE recycling process is suitable for appliances that are free from grease and grime and do not require pre-wash. The closed-loop system does not change the water column, but continuously filters out particulates with a fine Nylon mesh on a revolving belt, which is cleaned at one end by high-pressure water jets. Contact: Envirotec B.V., Duikerweg 32, 5145 NV Waalwijk, The Netherlands. Tel: +31 (416) 697 445; Fax: +31 (416) 697 311; E-mail: info@envirotec-rec.com.


Source: www.allbusiness.com

International Metals Reclamation Company Inc., the United States, has patented a rotary thermal oxidizer that removes polymeric and other non-metal components of exhausted batteries and cells leaving valuable metals such as nickel, cadmium and iron behind for subsequent processing.

Pre-heating the sweep gas to a temperature above the auto-ignition point of the polymers, prior to their introduction into the oxidizer, and controlling the oxygen content within the oxidizer, substantially reduces the risks of explosion and fire associated with the pyro-metallurgical recycling of the cells. The thermal oxidizer thus includes provision to pre-heat the sweep gas entering the oxidizer to adequately heat the cells and initiate polymer combustion under controlled conditions. A
water spray protects the oxidizer by controlling its internal temperature. It also controls the combustion of the entrained polymeric components, thereby avoiding the possibility of explosions. An explosion plate is included in the discharge housing as a safety device.

Source: www.freepatentsonline.com

Recycling devices built with plastic cases and other components such as mobile phones, mp3 players and personal digital assistants is difficult and needs repetitive manual labour. However, a new approach to creating the fastenings and tabs for such devices based on the shape-memory effect in plastics may allow the process to be automated. The approach proposed by Mr. Habib Hussein and Mr. David Harrison of the School of Engineering and Design at Brunel University, the United Kingdom would allow valuable components and metals to be recovered more efficiently from the millions of devices discarded every year.

The researchers studied the possibility of Active Disassembly using Smart Materials, which employs materials that can act as fasteners within a product and, at products end of life, can be undone simply by direct heating. This releases the fasteners, causing the device case to fall apart without manual intervention. This is an important design feature that might make recycling electronic devices with plastic cases much easier. According to the concept of shape memory effect, materials such as engineering plastics (polymers) can be fabricated in one shape the unfastened state and then moulded a second time into a new shape the fastened state. When the plastic in fastened state is heated, it will revert to its original unfastened state, because it retains a molecular memory of its original form.

The researchers have developed a case-fastening device based on one such shape memory polymer. Their tests demonstrated that lowering the device at end of life into hot water, leads to the fasteners reverting to their unfastened state and the case falling apart on agitation. They have also shown that the fasteners retain their integrity for at least two years without falling apart spontaneously.

Source: www.sciencedaily.com