Eaton helps Advetec keep waste digestion under control

Advetec's innovative thermal digesters make use of bio-stimulation, a method of invigorating and stimulating thermophilic and extremophilic bacteria so that they digest organic waste. So efficient is this process that the company's compact containerised digesters can process over 30 tonnes of waste in just 72 hours. The volume of the waste is reduced by 96 per cent, eliminating the need to send material to landfill. The only end products of the digestion process are clean water and a tiny amount of sterile residue.

Because they offer such an effective way of dealing with organic waste of all types, including "difficult' material such as abattoir by-products and hospital waste, Advetec digesters are finding a ready market all over the world. They are, however, usually installed in tough working environments and used by operators with skills more closely focussed on the physical handling of bulk waste than the operation of sophisticated control systems. Furthermore, they are often required to operate 24 hours a day, 365 days a year.

This combination of factors posed multiple challenges for the Advetec engineers working on control systems for the digesters. An easy-to-use intuitive operator interface was essential, and it was also important that, if a problem occurred, it should be possible to diagnose and rectify it easily and quickly, ideally without the need for an engineer to visit the site, which could be anywhere in the world. Finally, it was crucial that spare parts should be locally available irrespective of the location of the machine.

The first digesters produced by Advetec used a conventional control system that was largely satisfactory, but did not fully meet the requirements and challenges identified by the company. The Advetec engineers were, therefore, looking for a better option and, as part of the process of exploring the possibilities, they approached Eaton.

The engineers were immediately impressed not only with the high quality and wide range of Eaton automation components, which would cover all of the project's requirements, but also with the company's SmartWire-DT lean panel wiring system. The SmartWire-DT allows all of the major components within the control panel to be linked with standardised plug-in cables instead of ordinary panel wiring.

Detailed diagnostics

SmartWire-DT can also be extended outside the control panel so that, for example, machine-mounted sensors - which are the components most likely to suffer damage - become, in effect, plug-in devices. It also makes detailed diagnostics possible, as it allows easy access to detailed information about the status and condition of the connected devices. In addition, if any of the devices connected by SmartWire-DT are replaced, the system automatically reconfigures itself so that the new device is correctly addressed.

With these benefits in mind, the Advetec engineers decided to base the design of their new control system on Eaton automation products and SmartWire-DT. They also decided to use Eaton's XV-152 touch-screen operator interface panel, which has integrated programmable controller (PLC) functionality.

This robust device, which has a high ingress protection rating and a tough damage-resistant screen, allowed the Advetec engineers to develop a very easy-to-use operator interface based on colour graphics, while at the same time permitting a flexible scheme of control that can easily be updated should the need arise. The interface panel also allows users who are in possession of the appropriate security passwords to access the machine's comprehensive diagnostic system.

Advetec has now used Eaton automation systems in its two most recent machines and is planning to integrate it in all future machines. The company has found that SmartWire-DT simplifies the design, building, testing and commissioning of the control system, as well as allowing the size of the control panel to be reduced making it easier to accommodate.

The advanced monitoring and diagnostic system made possible by the Eaton technology conclusively proved its worth when the user of one of the new machines managed to insert a concrete building block along with the organic waste. As soon as the block stalled the transport motor, the diagnostic system detected the rapid rise in motor current and shut down the machine before damage could occur. After the block was removed, it was possible to restore normal operation of the machine immediately.

Craig Shaw, Managing Director at Advetec, says: "The new control system is proving exceptionally popular with our customers. They love the simple touchscreen user interface, they're impressed with the neatness and simplicity of the control panel and machine wiring, and are very enthusiastic about the diagnostics we've provided. Additionally, our customers like how easy it is to change sensors and other components on site without the need for specialist expertise.

"Eaton itself is, however, one of the biggest benefits for us. The Eaton name is recognised and respected worldwide, so our customers instantly see that we're using top-grade products in our machines. Even better, Eaton has a presence in more than 140 countries, so we know and our customers know that if spares should be needed, they will be delivered in less than 24 hours, no matter where in the world the machine is located."

To learn more about Eaton's power management products and automation components, visit www.eaton.uk.com/electrical.