A structured approach to technology selection based on engineering principles.
Choosing the right tertiary treatment technology is not about finding the ‘best’ technology — it’s about finding the right technology for your specific plant conditions. The selection process should be systematic: define objectives, assess constraints, screen technologies, evaluate lifecycle costs, and validate through pilot testing where appropriate. This page provides the engineering framework for making that decision.
The physical space available for new treatment infrastructure. Compact technologies like disc filters require as little as 20 m² per 10,000 m³/d.
Critical for retrofit projects.
Available gravity head between existing process stages and the new tertiary system. Determines whether gravity-fed or pumped operation is needed.
Impacts OPEX significantly.
Target effluent quality (TSS, TN, TP, micropollutants) and whether these are annual averages or absolute limits.
Defines technology shortlist.
Quality of secondary effluent entering tertiary treatment. High variability may require more robust technologies.
Affects sizing and technology choice.
Total cost including CAPEX, energy, chemicals, maintenance, and media/membrane replacement over 20+ years.
Often favours simple technologies.
Staffing requirements, automation needs, and maintenance frequency. Remote plants may need simpler, more autonomous systems.
Practical constraint.
| Technology | TSS | TP | Footprint | Energy | Retrofit |
|---|---|---|---|---|---|
| Disc Filter | XS | Very Low | |||
| Sand Filter | M | Low | |||
| DAF | M | Medium | |||
| MF/UF Membrane | S | High | |||
| MBBR (N-removal) | XS | Medium |
Get a preliminary engineering assessment tailored to your plant’s specific conditions and requirements.
Last reviewed: August 2026. Regulatory requirements may vary by national implementation. This content is for informational purposes and does not constitute legal or engineering advice.