Remarkable results, including smaller footprint, lower installation costs, minimal maintenance costs and major energy savings, were achieved at Broadholme WRC thanks to Anglian Water, APG-Neuros, Barhale & Air Technology Ltd.
Project Background
Secondary Wastewater Treatment at Broadholme WRC comprises of two Activated sludge Plants that are aerated using blowers and diffusers. Previously, the air was provided by three large centrifugal type units powered by 250 kW motors on variable speed drives. The blowers were installed in 1979 and were recently identified for full refurbishment.
The pre-site survey completed by APG-Neuros and the Anglian Water Energy Team included the review of existing equipment, process requirements, historical data, future demand requirements and measured data. This also included system control analysis to determine operation of equipment in order to ensure best practices and system optimization. Following this, an amended URS was written to adjust the control for optimization.
Once the preliminary design was outlined and agreed the construction phase plan, final costings and a project delivery plan was drafted indicating any potential issues that may arise. Any small items that arose from completing the documentation was amended before final submittal. Following acceptance by the customer final designs and project plans were issued for discussion in a project kick-off meeting between all parties involved in the project or effected by the project. This enabled a final sense check before project commencement to ensure nothing had changed since agreement and final submittal, ensuring all activities were possible within the time frame and would have a limited impact on each other.
Project Development
Removal of two existing rotary lobe blowers to be disposed of. Supply of two High Speed Turbo Blowers as replacements. Mechanically Install blowers and blower discharge pipework to an existing header, removing and disposing of old pipework and inlet silencers. Apply acoustic insulation to discharge pipework. Work closely with the IOS Electrical Contractor when installing supply and communication cabling to the APG-Neuros units. Integration and Commissioning of the new blowers within the process. Training of site staff in the operation and maintenance of the new blowers. Removal of the old and installation of the new blowers was staged, so that the process could be maintained throughout the blower exchange project.
Result
Following installation and an agreed period of constant operation the client provided latest energy draw figures and flowrates which were compared to previously recorded data. This confirmed pro-rated annual energy savings of £87,400 at the current £kW/h rate. Maintenance costs have dropped to almost zero. Savings are also reflected in a reduction in CO2 emissions by 392 tonnes. Only half the space was required to install the APG-Neuros blowers, which freed up a large proportion of the existing building which can now be used for other purposes. If installing APG-Neuros blowers on a new site, the size of any building would be much smaller than required for other technologies, making more efficient use of the space available, at the same time minimizing installation costs.
