Siemens provides ‘e-stop’ safety solution for coal preparation plant
26 January 2011
Miller Argent (South Wales) Limited, a company responsible for reclaiming land in Wales that incorporates opencast coal mining, has recently installed a Siemens safety solution on its new coal cleaning plant.
Miller Argent is responsible for the Ffos-y-Fran land reclamation scheme in Wales. The scheme is the third and final stage of the East Merthyr Land Reclamation Scheme, where derelict land is being reclaimed and the reclamation paid for by the sale of the coal recovered. Once complete, the site will be cited as a flagship reclamation scheme on an international scale.
In order for the coal that is extracted from the land to meet customers’ requirements, it must be cleaned in a coal preparation plant. This plant separates coal from stone and shale producing a high specification product that can be used in power generation, steel making and other industrial processes.
For the coal preparation plant to meet safety requirements under the Machinery Directive, a safety system which incorporated an ‘e-stop’ or emergency stop button had to be installed onto the machinery. This system was required to meet the category 3 safety requirements listed under safety standard BS954-1. The category 3 requirements state that wherever possible, a fault should be detected automatically by the safety system, so that the system instantly shuts down if there is a problem with the machinery.
Additionally, with a view to the future, the coal plant required the safety system to also meet the new standard EN954-1, which is set to provide more stringent safety requirements from the end of 2012.
Working with Nexdorf Electrical, Siemens provided a SIRIUS 3RK Modular Safety System (MSS) as the solution for use in the coal washery. It combines the functionality of a simple safety relay with that of a fail-safe programmable logic controller (PLC).
The SIRIUS 3RK goes above and beyond the safety standards required for the application. In addition to fulfilling the safety requirements for BS954-1 to category 4, it also meets the standards specified for regulations EN954-1 and SIL3, in accordance with IEC 61508/62061.
As the system features a modular design, users are able to attach more modules to the solution as necessary. Additionally, if a part requires replacement, the modular nature of the SIRIUS 3RK means that only the required part need be replaced rather than the entire solution. For future maintenance, this could result in significant cost savings and provide operational benefits, as downtime would be reduced and less staff hours required to carry out any maintenance.
Gareth Trewartha, managing director of Nexdorf Electrical, says:
“I always choose to work with Siemens’ safety solutions as I know that I can trust the products will be top quality and perform the job well. This application was no different and I was confident that the MSS product would prove to be the perfect solution for the coal washery. Safety is of paramount importance wherever there is machinery and so it is important that the necessary safety equipment is in place and that all legislative requirements are met. As the Siemens solution not only met the current safety requirements, but also those which are set to come into force at the end of 2012, it allowed the OEM and end user the opportunity to future proof the application and gave them confidence that the product would be as valid in the future as it was on the day it was installed.”
Paul Hingley, Siemens Industry Automation and Drive Technologies, says:
“We were very pleased to work with Nexdorf Electrical on such a high profile application as this. The project is being set out as an example of a flagship scheme and so we are pleased that Siemens have been able to provide safety equipment for this reclamation. Safety is always of utmost importance to Siemens and we are confident that the solution will stand the test of time and safety.”
For any further information, please contact 0845 7705070 / www.siemens.co.uk/automation.