HAVER & BOECKER

Efficient wastewater treatment in municipal sewage plants

Save time and energy with wire mesh

As the availability of clean, drinking-quality water becomes more critical, efficient wastewater treatment is essential for managing this valuable resource responsibly. Mechanical filtration solutions play a key role in treating wastewater effectively, ensuring it can be safely returned to the environment or even reused.

In 2022, Germany generated 8.33 billion cubic meters of wastewater.^[1] This total includes domestic and industrial wastewater, rainwater, and infiltration water. Public wastewater treatment plants aim to remove pollutants as thoroughly as possible to maintain long-term water quality and promote sustainability.

_{[1] cf. Statistisches Bundesamt (Federal Statistical Office): "Öffentliche Abwasserbehandlung 2022" (Public Wastewater Treatment 2022), October 2024}

Topics covered

Mechanical wastewater treatment
Microscreen systems: Efficient pre-treatment for energy recovery
Success factors for effective wastewater treatment

Step one: Mechanical wastewater treatment

Mechanical cleaning is the first and most fundamental step in the wastewater treatment process, responsible for removing up to 30% of organic pollutants.

It begins with coarse filtration in which rakes or screens remove larger debris. This is followed by sand and grease traps that separate fine solids (e.g., stones, glass shards) and floating materials like oils and fats. In the primary clarifier, the flow slows to allow suspended solids like feces and paper to settle.

Mechanical filtration systems are essential for:

Protecting downstream equipment
Reducing biological process loads

During the biological stage, bacteria and oxygen break down dissolved organic matter and nutrients. If necessary, chemical treatment follows to remove difficult substances like phosphates, heavy metals, and salts.

Sketch of a cleaning process in a sewage plant — Image: Illustration of a typical municipal wastewater treatment process

Microscreen systems: Efficient pre-treatment for energy recovery

To increase energy efficiency, modern wastewater treatment plants are adopting microscreen systems.

These systems filter solids from the water before the main treatment process begins, enabling the use of sewage sludge in biogas production. This offsets the facility’s high energy needs.

To perform effectively, microscreen systems must:

Deliver high filtration precision
Withstand mechanical and chemical stress

Mechanical stress comes from high-pressure cleaning and cavitation (pressure fluctuation during flow). Wire mesh offers an ideal solution, easily integrated into existing systems.

Section of a micro screen with wire mesh — A wire mesh filter medium can be easily integrated into existing systems.

Filter selection starts with the system design

Wire mesh wastewater filters can be easily integrated into existing wastewater treatment plants as filter candles, flat sieve mesh, or filter plates.

Key benefits of wire mesh in microscreen systems include:

Ultra-fine pores that capture solids, sand, microplastics, and bacteria
High flow rates with minimal pressure loss
Excellent dirt-holding and self-cleaning capacity
Stability and corrosion resistance in harsh conditions

Success factors for effective wastewater treatment in sewage plants

Flow rate

Filters must withstand mechanical and chemical cleaning. The ideal cleaning interval depends on balancing flow rate with dirt-holding capacity.

Filter fineness

Twilled weave or laminated wire mesh efficiently removes fine suspended solids, microplastics, sand, and bacteria.

Material selection

Corrosion resistance is crucial, as filters are continuously exposed to water. Welding properties are also important, as filter elements are often formed and fixed via welding.