Unique renewable energy source upgrade

Bran Sands, Middlesbrough, UK, Regional Sludge Treatment Centre (RSTC) is a modern waste water treatment site, built just 10 years ago and using technology to deliver innovative solutions to the problem of wastewater treatment and sustainable environmental sludge disposal. When a key machine required a composite hardware and software update, Northumbrian Water chose SolutionsPT, part of the Pantek group of companies, to deliver improved reliability, local support and a seamless transfer.

Northumbrian Water constructed the Bran Sands facility on a site that was previously used for landfill of industrial waste. The planning requirements were strict, but the site was needed to meet a rising demand for treatment of both domestic and industrial effluent. Rigorous ground preparation involved a complete site membrane and the company had to decide on an effective method of treatment. The method chosen was to feed the raw sludge into a drying system that produces an end product of dry granules free from pathogens and usable for

agriculture and as a highly combustible fuel.

The fuel is being used by a UK cement producer. The granules are combusted to provide heat for the cement kiln. There is no waste as the resulting ash is embodied in the cement, a complete environmental solution.

Seven process lines

At the heart of the drying process is an Andritz drum dryer, in fact seven dryers form the seven process lines that were installed in two phases.

The first phase was built to process 50,000 tonnes of dry solid per annum (tds/a), the second phase extending this to 75,000 tds/a.

The plant is rare in that it dries raw (unprocessed) rather than digested sludge. This maximizes the potential for the dried sludge to be used as a fuel by maintaining a higher calorific value in the final product and negated the requirement for installation of expensive digestion plant.

The SCADA control system was supplied by the dryer company and was centered on Wonderware’s InTouch running on bespoke hardware. This was becoming difficult to support owing to its special nature and long support channels, plus the software was at an earlier revision than current and therefore did not contain several features that were attractive for ongoing site development. Northumbrian Water’s engineers had to procure a rugged platform that had local support while still meeting the technical requirements of the site and being able to support any additional development that may be required.

Solutions provides the solution

Following a SolutionsPT sales event in Middlesbrough, attended by Northumbrian Water engineers, it was clear that SolutionsPT could provide not only hardware from its Advantech range, but also a complete configuration service and bring the Wonderware InTouch to the current version level.

The company prepared a detailed site survey and listed a scope of work that would be beneficial to the reliable running of the plant and also provide better operating and maintenance access. A relatively straight forward task, but all of

this had to be done without incurring downtime in what is in effect a continuous process with sludge arriving continually by pipeline, road tanker and by sea, on a system with 7000 data points.

Both the old and new systems run in Master/Slave configuration and this allowed work to proceed by changing the servers over to effect replacement. The server operating system was upgraded to Windows XP and the latest version of Wonderware InTouch 9.0 was loaded and an audit made of the application software.

This later aspect required additional attention, as there was a disparity between the versions used across the site. The servers were also fitted with high-speed communication cards for fast access and load removal from the CPU for this

function. Woodhead SST intelligent communication cards were supplied by

SolutionsPT to the server configuration, connection to Data Highway+ being required for all machines.

Additionally, operator workstations were upgraded and flat screens installed in the control room consoles to improve the clarity of displayed information. A fully configured cold spare server is stored on site as insurance against a catastrophic failure.

The original machine manufacturer has been fully updated with documentation for the new scheme and is therefore retained as a key contributor to Bran Sands’ on-going success.

David Charlton, Northumbrian Water’s Bran Sands site manager, says: “Since we have changed the system it has operated more efficiently.” Mike Smith, Northumbrian Water’s SCADA engineer, adds: “The single point of contact overcame the high risk levels in the changeover. SolutionsPT’s engineer, John Suter, provided an experienced and capable approach to the whole project.”

The site has continual data logging to meet with stringent regulatory compliance by the Environment Agency; data was logged throughout the changeover period, the switchover to the new system being described by Steve Coverdale, NWL Plant Engineer as “smooth”.

Despite the complexity of Northumbrian Water’s requirements and the site-wide risk in the changeover, SolutionsPT reduced the immediate and significant risk of failure of the key drying machines’ control systems; local support has delivered a single source solution based on sound engineering that is universally endorsed by key NWL managers.