Wastewater Aeration for Biological Treatment
For biological aerobic treatment, wastewater aeration is the most important aspect in terms of operating expenses OPEX, so the choice of aeration technology is one of the most critical decisions in plant design, directly impacting operational efficiency, energy consumption, and final effluent quality.
The most important aeration technologies can be broadly categorized into two main types:
- Diffused aeration and
- Surface aeration, with hybrid systems like jet aeration, also playing a significant role.
The primary goal of these technologies is to maximize the air-water interface to facilitate efficient oxygen transfer from the air into the wastewater. This is quantified by the Oxygen Transfer Efficiency (OTE), a key metric for comparing different systems.
Diffused Wastewater Aeration Systems
Diffused aeration is the most prevalent and energy-efficient method used in modern wastewater treatment plants. In these systems, compressed air is released from below the water surface through diffusers, creating bubbles that rise through the water column, transferring oxygen as they ascend.