One of the UK’s leading recyclers of IT and telecommunications equipment is Engelhard, part of the BASF Group. Typical products recycled at the company’s plant in Cinderford, Gloucestershire, include computers, monitors, printers, fax machines, photocopiers, mobile phones and pocket calculators. Integral to the business is the recovery of precious metals – such as gold, silver, platinum, palladium and rhodium – from circuit boards and other electronic components.

Part of the process involves using a high-temperature scrubber to burn off the plastics that cannot be economically recycled. However, this results in fumes laden with hydrochloric acid, which have to be neutralised with a caustic liquid.

The resulting liquor gradually becomes contaminated with mainly carbon particulates until it reaches the point where it has to be filtered and processed, ready to be reused. Twice a day, hundreds of gallons of this highly aggressive, hot (50–60°C), particulate-laden fluid have to be pumped from the scrubber to the filter bed in under one hour.

The peristaltic pump that was originally specified for this task soon proved to be troublesome, requiring monthly hose changes and, even then, hoses still occasionally burst due to high back pressures caused by blockages. Other pump-related failures also occurred, and spare parts were not readily available from the manufacturer, which was based in mainland Europe.

As a result of this pump’s problems, Engelhard was suffering from downtime, the cost of spare parts, additional costs for stocking hard-to-get spare parts, and each time the maintenance engineers were called to attend to the pump, they were unable to continue with their other work. Over a period of several years, virtually every part on the original pump failed, including the guard, the rollers on the rotor, and even the geared motor.

Crest Process Engineering, which helps Engelhard to maintain the plant, recommended upgrading to a Watson-Marlow Bredel pump. Despite initial reservations over the slightly higher cost of the Watson-Marlow pumps, Engelhard agreed to purchase an SPX50 peristaltic pump, which is capable of delivering a maximum flow rate of 62litres/minute (800gallons/hour) and, much to Engelhard’s relief, benefits from a two-year warranty and UK-sourced spares (Fig.1).

One year on, Gary Williams, the maintenance supervisor, is pleased with the pump’s performance, saying: “Considering that each pump failure was resulting in 12–15 hours of downtime, plus we have not had to spend any money on spare parts, the new SPX hose pump has probably paid for itself already.”

Perhaps as importantly, the pump is no longer a headache for the maintenance department, enabling resources to be better deployed in keeping other parts of the plant in first-class condition (Fig.2).

Engelhard Sales Limited is now known as Refining and Recycling Services Limited.