The company’s wastewater treatment plant in Belfast requires blowers to aerate the site’s sequencing batch reactors and treat wastewater. By oxygenating the activated sludge within the reactor with aeration air, the blowers help break down organic compounds within the wastewater.

　　Charles Brand previously used five 132 kW oversized blowers for this aeration process. These units were 16 years old and required increased maintenance to keep them in good working order. The company’s compressors suffered three failures in as many months, with each repair costing in the order of ￡6,000. Faced with escalating costs, Charles Brand identified that savings could be made by upgrading their aeration system using advances in blower technology.

　　The revolutionary solution – the first of its kind in the UK – involved replacing three of the 132 kW units with 75 kW Robuschi WS 85 Robox Energy screw blowers, with a payback period of three years.

　　The Robuschi Robox Energy screw blower combines a screw compressor with a permanent magnet motor, allowing for pressure up to 1000 mbar(g) and capacity up to 2,600m3/h. Its internal compressor, combined with an efficient permanent magnet motor, is directly fitted to the conductor shaft to prevent loss of power from the belt drive.

　　Charles Brand is also able to monitor the operation of the entire unit via an intelligent HMI control panel. This can be remotely connected, meaning performance can be monitored anytime, anywhere, and help inform predictive maintenance.

　　The screw blower requires 30 per cent less space than comparable units and comes complete with an integrated variable frequency drive (VFD). The units were installed in simple ‘plug-and-play’ fashion. Operators needed only to connect the piping, electrical power line and control panel to the system.

　　These features mean the Robox Energy screw blower can offer energy savings of up to 30 per cent, which makes it ideal for the energy-intensive wastewater treatment sector.