Case Study:

Central Otago District Council Wastewater Treatment Plant

Reflecting on Success: The First Aerdisc® Installation in Cromwell

In June 2022, the Central Otago District Council’s municipal wastewater treatment plant in Cromwell became the first site to adopt Aerdisc® Directional Aerators by Aeris Global. As we revisit this milestone project, we’re thrilled to report significant improvements in wastewater treatment efficiency and operational performance achieved through Aerdisc technology.

Project Overview

  • Location: Cromwell, Central Otago, New Zealand
  • Specifications: Two (2) ponds, total area [?], partially screened
  • Catchment Population: 10,000
  • Installation Date: June 2022

Challenge

The existing wastewater treatment system at the Cromwell plant faced several challenges:

  • Extremely Low Dissolved Oxygen (DO) Levels: The existing equipment struggled to maintain adequate DO levels, hindering the biological treatment process.
  • High Power Consumption: Inefficient aeration resulted in excessive energy use, driving up operational costs.
  • Poor Mixing Efficiency: Short-circuiting and ragging issues hampered effective mixing, compromising treatment quality.

Objective

The Central Otago District Council sought a solution to:

  • Enhance oxygen transfer and mixing efficiency within the wastewater ponds.
  • Increase overall DO levels to optimise biological treatment processes.
  • Reduce ragging and short-circuiting for improved treatment consistency.

Solution

Aeris Global deployed two Aerdisc® Directional Aerators as a strategic solution. These revolutionary aerators boast:

  • Advanced Directional Mixing: The Aerdisc® design ensures efficient and targeted mixing throughout the ponds, eliminating short-circuiting and maximising treatment effectiveness.
  • High Oxygen Transfer Efficiency: Aerdisc® technology delivers superior oxygen transfer rates, significantly boosting DO levels within the wastewater.
  • Low Maintenance Design: The Aerdisc® units require minimal maintenance, reducing operational downtime and costs.

Results (June 2022 – June 2024)

Following the installation of Aerdisc® Directional Aerators, the Central Otago District Council experienced remarkable improvements in their wastewater treatment process:

  • Improved Mixing Efficiency: Mixing efficiency increased by 35%, resulting in more thorough treatment and a reduction in short-circuiting.
  • Energy Savings: Energy consumption for aeration processes decreased by 20%, leading to significant cost savings.
  • Maintenance Reduction: Maintenance requirements were reduced by a staggering 80%, thanks to the low-maintenance design of the Aerdisc® units.
  • Operational Uptime: The Aerdisc® units have delivered 100% operational uptime over the past two years, ensuring uninterrupted treatment processes.
  • Ragging Elimination: The innovative design of Aerdisc® eliminates ragging issues, minimising downtime and maintenance needs.

Conclusion

The successful implementation of Aerdisc® Directional Aerators at the Central Otago District Council wastewater treatment plant exemplifies the transformative potential of Aeris Global’s aeration technology. This project demonstrates how Aerdisc® can significantly enhance treatment efficiency, reduce operational costs, and ensure reliable performance for municipalities.

Interested in transforming your wastewater treatment process?

Contact Aeris Global today to learn more about how Aerdisc® Directional Aerators can optimise your wastewater treatment operations.

"The Aerdisc units have exceeded our expectations, providing consistent performance and reliability. We've seen substantial improvements in our wastewater treatment processes, leading to better environmental outcomes and operational efficiencies."

Duncan McInnes

Water Service Operations Team Leader for the Central Otago District Council