If your aeration system has been running for years without inspection or upgrades, chances are it's costing you more than it should. Aging blowers, fouled diffusers, and inefficient air distribution can quietly drain your energy budget while reducing treatment performance. Many plants continue running outdated equipment far past its prime simply because it still "works", but in wastewater treatment, function alone isn’t enough.
Fortunately, upgrading doesn’t have to mean ripping out your entire setup. With a strategic approach, you can modernize your system in phases and gain significant improvements in performance and operating costs. In this guide, we break down 3 smart steps to upgrade your old aeration system, designed to deliver long-term efficiency without disrupting plant operations.
Step 1: Assess System Performance and Energy Use
Before replacing components or redesigning pipework, you need to clearly understand how your current aeration system is functioning. Start by gathering operational data over a 2–4 week period. Track blower power consumption (kWh), dissolved oxygen (DO) levels at multiple points in your aeration tank, airflow rates (if available), and daily load variations. If you don’t already have inline DO or energy meters, even portable tools can help establish useful benchmarks.
Pay close attention to the following warning signs:
Conducting a Specific Aeration Energy (SAE) analysis (kWh per kg of oxygen delivered), can also highlight inefficiencies that might not be obvious day-to-day. This value should ideally trend downward as you make improvements.
If you find major performance gaps, document their likely causes. Are you still running the original diffusers from system commissioning? Has your process changed while blower capacity stayed the same? This assessment becomes the foundation for a targeted, cost-effective upgrade strategy.
Step 2: Upgrade Diffusers and Optimize Airflow Distribution
The condition and design of your diffusers have a major impact on oxygen transfer efficiency (OTE). Over time, membranes harden, pores clog, and bubbles grow larger, reducing how effectively air reaches your microorganisms. Simply increasing airflow to compensate for poor diffuser performance will only raise your energy bill.
Modern fine bubble diffusers, especially those made from PTFE-coated EPDM or silicone, offer far greater resistance to fouling and degradation than older models. Replacing aging diffusers can boost OTE by 10–20%, often paying for themselves in energy savings within 1–2 years.
Don’t just swap diffusers without rethinking the air distribution:
Focus on the zones with the poorest DO performance first. A phased upgrade allows you to spread costs while achieving visible results early. After initial upgrades, recheck OTE and DO levels to ensure changes are producing the intended impact.
Step 3: Improve Blower Efficiency and Control
Your blowers are the heart of the aeration system, and they consume more energy than any other component. If you’re operating blowers installed more than a decade ago, there’s a strong chance they’re oversized, poorly controlled, or simply outdated in terms of energy efficiency.
Begin by verifying whether your current blowers are correctly matched to your plant’s actual oxygen demand. In many facilities, flows and loads have changed over time, but blower capacity hasn’t. Oversized blowers cycling frequently or running inefficiently at partial loads waste a significant amount of energy.
Upgrading your blowers can involve:
For smaller systems, high-efficiency positive displacement blowers may still be appropriate, especially if loads are relatively stable. In all cases, the goal is to reduce energy waste while maintaining or improving biological performance.
Don't forget about integration: newer blowers often come with advanced monitoring features that can feed into SCADA systems, allowing plant managers to optimize in real-time and track trends over the long term.
Bonus Step: Monitor, Measure, and Maintain
Final Thoughts
Upgrading your aeration system doesn’t have to be disruptive, expensive, or all-or-nothing. With the right strategy, you can dramatically improve energy efficiency, oxygen transfer, and overall plant performance by replacing aging components, tuning air delivery, and modernizing blower control.
Whether you’re managing a municipal plant or an industrial facility, these three steps: assess, upgrade, and optimize -offer a clear, scalable path to better results.
Need help getting started? Contact PureDutch. We provide high-efficiency diffusers, smart blower solutions, and hands-on support to help you build an aeration system that’s ready for today and scalable for tomorrow.
