Why Municipal Plants Are Turning to Ozone
Municipal wastewater treatment operators are under pressure from two sides: rising sludge disposal costs and tougher rules on trace organic contaminants. Ozone-based oxidation has emerged as a practical response to both challenges. A recent project in Bottrop, Germany, illustrates how one integrated ozone system can address sludge reduction and micropollutant removal at the same time, while also accommodating tighter European regulations.
The Bottrop Project at a Glance
Bottrop’s wastewater treatment plant serves approximately 1.34 million population equivalents and has a maximum design flow of 8.5 cubic meters per second. The facility recently started an upgrade centered on a new-generation ozone system, the Evotide, developed by WEDECO, a Xylem brand. This installation is the first global project order for Evotide since its launch, marking an important step from product introduction to real-world municipal application.
Two Targets: Sludge Reduction and Micropollutants
Sludge Reduction as a Cost Levers
Sludge disposal now represents a significant share of operating expenses for many treatment plants. Rising transport, energy, and final disposal costs make volume reduction an attractive financial strategy. The Bottrop project uses ozone to oxidize part of the sludge, breaking down cell structures and complex organic matter so subsequent biological treatment can degrade it more easily. The target is a 30 to 50 percent reduction in excess sludge production. Additional benefits include better sludge settling, less sludge bulking, improved dewatering, lower chemical consumption, and reduced overall operating costs.
Micropollutant Removal and Regulatory Pressure
The same ozone capacity will support research into micropollutant removal. Tests in a dedicated pilot basin will evaluate how effectively ozone oxidizes pharmaceutical residues and ingredients from personal care products. These compounds are often present at very low concentrations but are difficult to remove with conventional biological treatment. Ozone is already recognized as a mature advanced oxidation technology for this purpose. The revised EU Urban Wastewater Treatment Directive, published in 2024 as EU 2024/3019, strengthens these requirements by setting an overall removal target of 80 percent for relevant micropollutants. That regulatory push is prompting more European plants to assess ozone as a deep-treatment step, and Bottrop is an early practical example.
One Ozone System, Split Responsibilities
The Evotide system installed at Bottrop provides a total ozone output of 20 kilograms per hour at 10 percent weight concentration. Of this capacity, 16 kilograms per hour is dedicated to sludge oxidation, while up to 4 kilograms per hour supports micropollutant removal trials. This flexible split lets the plant prioritize sludge reduction while still gaining operational data on advanced treatment for trace contaminants.
Container Design Makes Retrofits Easier
For existing plants, retrofit complexity often matters as much as technical performance. Evotide uses a containerized design that integrates the ozone generator, electrical controls, and auxiliary equipment onto a common platform. The unit is fully assembled and tested at the factory before delivery. That approach reduces on-site installation work, shortens commissioning time, lowers system integration risks, and minimizes disruption to ongoing plant operations. It is an attractive feature for municipal facilities that cannot afford extended downtime.
Energy Efficiency Gains with Effizon evo 3G
Evotide incorporates WEDECO’s latest Effizon evo 3G electrode technology. Compared with the previous generation, the system can cut energy consumption by up to 15 percent while maintaining stable ozone output across a wide operating range. It also requires less maintenance and has a lower risk of unplanned stoppages. For municipal plants that operate continuously for decades, these improvements directly affect life-cycle costs and reliability.
What This Means for Buyers and the Role of Filtration
The Bottrop project shows that ozone is no longer only about disinfection. It is an operational tool for cutting sludge handling costs and meeting new micropollutant limits. Water-treatment buyers should look beyond the ozone generator itself and consider the entire treatment train. Effective upstream filtration is essential to protect ozone equipment and reduce ozone demand caused by suspended solids. For high-flow municipal and industrial applications, Spuretek’s SHF big-flow pleated cartridges deliver consistent removal with lower energy draw. Where pre-treatment deals with larger particulate loads, Spuretek SFB filter bags offer a cost-effective solution. For plants seeking durable, reusable media, the Spuretek SSSP stainless steel pleated cartridge can handle demanding service conditions while simplifying maintenance. Selecting the right filtration stage before an ozone unit can extend equipment life and improve overall process stability.
As the industry moves from simple discharge compliance to broader resource efficiency, integrated solutions that combine oxidation and filtration will become more valuable. For advice on filter selection or to discuss your pretreatment needs, contact Spuretek Filtration Co., Ltd. at https://www.spuretek.com. Source: H2O-China, https://www.h2o-china.com/news/364529.html.
Based on reporting by H2O-China. Original analysis and product perspective by Spuretek Filtration Co., Ltd.. Read the source.