Trickling Filter


A time-tested technology, trickling filters offer a simple, cost-effective, energy-efficient treatment solution. With more than 500 trickling filter installations worldwide, Brentwood’s media and components have been optimized to guarantee the best performance for any application. By maximizing surface area in a given volume, Brentwood’s structured-sheet media provides an ideal environment for microorganism growth.

Brentwood media is rigorously tested for compression strength to ensure the structural integrity required for deep towers and demanding applications. Our dedication to quality and media performance is clear throughout Brentwood’s history with many installations in operation for over 20 years.

Structured-Sheet Media Features

  • Maximizes surface area per unit volume

  • Creates even liquid distribution over biofilm

  • Allows air circulation through media

  • Provides drainage for excess biomass

Learn More About Trickling Filter Products

trickling filter


Trickling filter applications vary based on media selection. Brentwood offers a variety of structured-sheet, plastic media configurations with differing flow patterns and surface areas to meet site-specific treatment objectives: BOD roughing, BOD removal, nitrification, and combined BOD removal and nitrification.


Trickling Filter Technology

Trickling Filter Technology

Learn how trickling filter technology has evolved over the years to continually meet industry needs.

System Components

System Components

Filter Media

Cross Flow Media

By combining high surface area with a maximum number of mixing points per unit volume of media, cross flow media facilitates superior process performance across a wide range of hydraulic wetting rates. The cross-corrugated modules provide continuous and uniform horizontal distribution of both air and water throughout the full media depth.

Trickle Filter

Vertical Flow Media

Media is also available in vertical flow configurations, which can be combined with cross flow media for superior solids flushing. Vertical flow media allows a thinner biofilm to be retained and minimizes biomass accumulation.

Trickle Water System Supports

AccuPier® Support System

Fixed-film media is elevated above the concrete tower floors with a corrosion-resistant support system that can be customized for any application and engineered to maximize ventilation and drainage.

Bio Grating for Filter Media

AccuGrid® Bio-Grating

Interlocking panels provide a protective layer from foot traffic, hydraulic impact, and UV degradation on top of trickling filter media.



Process Design Pilot Testing Startup & Operations Assistance
Industrial Water Filter

Process Design

Brentwood’s proprietary trickling filter models are developed based on industry-standard methodologies and carefully calibrated for each type of structured-sheet media. Our process assistance has supported hundreds of successful trickling filter installations worldwide and can be applied to preliminary design or existing process evaluation.

Effluent Treatment

Pilot Testing

Our experienced engineers can develop pilot protocols, size the pilot equipment, and analyze performance data to help our clients optimize system design. Brentwood can supply either skid-mounted pilot units to your site, or we can send our mobile testing lab—equipped with advanced instrumentation and PLC control—to run full, sidestream pilot tests.

Bio Filter Media

Startup & Operations Assistance

Brentwood’s systems and components are engineered not only for performance, but for ease of installation. With a dedicated team of site technicians who have assisted in over 500 installations, you can be assured that the system will run properly, and your employees will be educated and prepared to operate the system. Additionally, Brentwood’s process team is available for consultation throughout the lifetime of the trickling filter system to provide maintenance advice and to ensure continued performance results.

Articles & Literature

Articles & Literature

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