Pump Performance Keeps Coal Mine Afloat

15 October, 2009

Sykes Pumps key to success at Stobswood

Located in Northumberland, Stobswood OCCS commenced operations in January 1990, producing 12.5 million tonnes of coal from an area of some 650ha. Following the North Stobswood Extension granted by Northumberland County Council in 2006, an additional 1 million tonnes of coal, together with 27,000 tonnes of ancillary fire clay, was extracted by operators UK Coal, with the mine now being backfilled and landscaped to an improved restoration profile.

For both UK Coal and their customers, primarily power stations across the country, maintaining the efficiency of the mining operation at Stobswood was business critical. Any delays in production would have had significant knock-on effects on the supply chain and, ultimately, delivery to power-generation customers. As a result, UK Coal took every possible precaution to ensure that the site remained operational at all times, and keeping the mine dewatered was one key area to which the company paid particular attention.

Working well below the natural water table meant that water presented a constant challenge for the company and, if not properly managed, seepage into the working area could have quickly flooded the site. Added to this was the problem of rainfall; in the Northumberland countryside, flash floods caused by heavy downpours are a constant risk.

If the water levels at the mine had been allowed to rise, production would have been severely disrupted, so, for the UK Coal team managing the site, ensuring that this did not happen was critical. Having used the expertise of hire specialists Sykes Pumps on the original Stobswood Site, UK Coal turned to them again for help with the extension.

‘We had past experience of using pumps from Sykes Pumps during excavation of the main Stobswood Site, so we not only trusted them to specify the most appropriate pump for our needs but knew that we could rely on the quality of their maintenance and service commitment. Because the smooth operation of the mine relied on the pump’s ability to run efficiently 24h a day, a level of confidence was very important,’ commented site manager Peter Millar.

UK Coal calculated that the North Stobswood Extension would require a pump capable of pumping the water to a vertical head of 90m, in order to move the water from operational area to the approved discharge point. With this as their brief, Sykes Pumps recommended a UVO 200/150F (D90) pump for the application.

‘We have been involved with several surface coal mines in both the Northumberland and Co. Durham areas,’ explained Darren Watson, from Sykes Pumps, ‘so we understood the challenges of this kind of environment and were well placed to specify the right equipment for the job.’

The UVO 200/150F (D90), a high-head pump designed for arduous conditions, is well suited to pit dewatering applications. The pump can provide a vertical head of 135m and is capable of pumping at a rate of 375 litres/s, so the Sykes Pumps team knew that it would easily meet the scope of UK Coal’s requirements for the North Stobswood Extension, with capacity to spare.

‘Once in place, the pump was able to dewater the site very quickly, allowing mining to begin,’ continued Mr Watson. ‘It then continued to maintain a dry working area, ensuring that coal seam extraction continued on schedule.’

Often used for pumping liquids with a high sludge or slurry content, the heavy-duty UVO 200/150F (D90) pump also offers high levels of abrasion and corrosion resistance, thanks to the high chrome/iron alloy used to manufacture its wet-end parts. This adds to the pump’s reliability and performance, and reduces the possibility of unforeseen maintenance issues.

While the UVO 200/150F (D90) is designed to cope with the challenges of a surface coal mine, neither UK Coal nor Sykes Pumps were willing to take any chances on reliability and therefore the hire contract included an engineer on 24h call-out.

‘The call-out engineer offered us peace of mind,’ commented Peter Millar. ‘We were confident that the chances of a breakdown were minimal but having a contingency in place is an integral part of effective mine management and it meant we knew that any critical problems that might arise would be dealt with quickly.’

In reality, the likelihood of the pump breaking down was relatively small, as Sykes Pumps have a standard 14-day/500-operational hours routine maintenance regime for all pumps out on hire.

‘As all mine operators know, maintaining business-critical equipment is the best defence against any unscheduled downtime because it’s during routine checks that any potential causes for breakdowns are spotted,’ explained Darren Watson. ‘Maintenance visits also allow us to check on the pump’s performance and advise on any support that may be required with running or manoeuvring the pump.’

Peter Millar concluded: ‘Our planning approval for Stobswood includes a clear commitment to complete the site to its full restoration profile within a pre-determined time frame. The efficient pumping equipment allowed us to keep the mining operation on schedule so that we can now look forward to delivering that commitment in full.’