An important district heating scheme in Sheffield, which generates heat and energy from waste wood, has come to fruition with the help of an integrated packaged pump solution from Armstrong Fluid Technology. The pump solution incorporates six large Armstrong 4300 Series variable speed pumps with built-in inverters, integrated with Armstrong’s IPS 4000 pump controller, which optimises operation of all six pumps to minimise energy consumption.
When planning the pump house for the district heating scheme, R K District Heating Limited had a number of priorities. The pumping requirements for the scheme are complex and involve handling of water at high maximum temperatures (up to around 115°C). The plant needs to offer outstanding levels of energy efficiency across a wide range of operating conditions, as the district heating scheme is being expanded incrementally over time. In addition, the demanding timescales for the project meant that the equipment needed to be installed within shorter than average lead times.
Source: Armstrong Fluid Technology
The company chosen to supply the integrated pump solution was Armstrong Fluid Technology – an expert in packaged pump solutions and integrated plantrooms with extensive experience of biomass-based systems. At the heart of the system are six Armstrong 4300 DE variable speed pumps integrated with Armstrong’s IPS4000 Pump Controller. The variable speed pumps incorporate on-board inverters which enable them to respond instantaneously and automatically to changing requirements, adjusting their motor speeds and drawing only the power required to meet the load. As they are Armstrong DE (Design Envelope) models, they also provide energy efficient operation across a wider operational range than other pumps, providing flexibility to adapt in the future without the need for replacement or system over-sizing.
The pumps are controlled by the Armstrong IPS4000 which calculates how best to meet demand and automatically manages pump operation accordingly.
The IPS4000’s advanced control technology ensures that pumps are operated at their most efficient points at all times, and are phased in and out in the best possible configurations to deliver the required capacity. By treating the system holistically, and balancing supply across all six pumps, the IPS4000 is able to achieve levels of efficiency that exceed those made possible by less sophisticated capacity-based control methodologies.
As the biomass-based district heating scheme has a particularly wide range of operating scenarios, the advanced control made possible by the IPS4000 ensures that energy efficiency is optimised whatever variations may occur. In the future, as additional plant rooms across the Sheffield area are integrated with the district heating scheme, the IPS4000 will ensure that the pumps adapt to accommodate the changing requirements whilst still maintaining optimum energy efficiency. The additional flexibility and sophisticated control provided by the Armstrong pumps and IPS4000 controller means that the energy wastage associated with over-sizing of systems is avoided.
The specification of integrated pump solutions from Armstrong Fluid Technology also had significant advantages in that it harnessed the benefits of off-site manufacture. Instead of being constructed in the traditional way (with components being delivered individually and assembled on site) the integrated pump solution was assembled, integrated and tested off-site, at Armstrong’s purpose designed factory in Halesowen. The completed pump solution was supplied to site ready-assembled just requiring final connection. Off-site manufacture ensured that all components for the pump solutions were connected and integrated exactly as required, maximising control over the final quality of the systems and ruling out the risk of errors. Using this approach, the timescales for delivery of the project were also reduced significantly, with assembly of the packaged plant able to progress concurrently with on-site construction, unaffected by adverse weather or other potential delays.
A number of valuable practical benefits were also provided by the Armstrong integrated pump solution. The pumps are designed to be an integral component of the pipework, eliminating the need for inertia bases, springs, flexible pipe connectors, field grouting and alignment. This provides a tidier, easier to access pump room, whilst the dynamically balanced impeller, and the shaft assembly rotating vertically on the pump centreline provides quiet, long lasting operation with minimum vibration. The pumps also feature space-saving Suction Guides and FloTrex valves which reduce the requirement for pipework and fittings, and perform multiple functions with a single component.
David Forrest, Project Manager at R K District Heating commented, “The pump house for the Blackburn Meadows district heating scheme was a complex and challenging project, so it was crucial to put together the best possible team to deliver it.
“I have had favourable experience of Armstrong’s work in the past and had no hesitation in specifying them for this project. All parties involved in the project, including Matrix and NIS Insulations, as well as Armstrong, worked together extremely effectively and this enabled us to reduce the project timescales by around six weeks.
“The control technology of the Armstrong pumps means that they take care of themselves, with very little need for supervision or intervention by our engineers. The neatness of design (for example there are no flexes or inertia bases) means that I can maintain high standards of presentation for the pump house, and the lack of vibration and noise means that, despite the scale of the scheme, this is a pleasant area for our engineers, and for the many visitors who come to this high-profile site”.
Wayne Kuczer, Area Sales Manager – North, Armstrong Fluid Technology added, “We were delighted to be involved in such a prestigious project. Pump control technology is crucial in a project of this complexity to ensure that the equipment operates to its full potential, and our IPS4000 is excelling in this application. The project was also managed by a team who were extremely conversant with its technical aspects and this assisted each of us in the supply chain to contribute our part of the project successfully”.