Paques BIOPAQ - Model CBD -Anaerobic Wastewater Treatment Reactor
The BIOPAQ CBD reactor is a specialized anaerobic treatment system designed to manage high-strength industrial effluents with significant organic loads and suspended solids. Unlike most systems that necessitate pre-treatment, this system can effectively treat wastewater containing up to 150 g/L of Chemical Oxygen Demand (COD) and 100 g/L of Total Suspended Solids (TSS). Integrated with an automatic grit and solids removal feature, the system mitigates build-up and operational downtime. Utilizing a plug-flow design, the BIOPAQ® CBD eschews mechanical mixing, resulting in lower operational expenses through diminished power consumption and maintenance requirements. Renowned for its biogas production efficiency, this reactor is especially suitable for industries with demanding effluent profiles, offering reliable performance and operational efficiency within a compact footprint. With years of proven global installations, Paques continues to lead in delivering robust, tailored solutions for complex wastewater treatment challenges.
BIOPAQ CBD is the only biological wastewater treatment technology designed to handle both extreme organic loads and heavy solids, with automatic grit removal built in the bioreactor.
Why choose BIOPAQ CBD?
BIOPAQ® CBD (Clean Bottom Digester) is purpose-built for industries where high COD and high solids go hand in hand.
While most anaerobic systems require pre-treatment or clean influent, CBD efficiently treats wastewater with up to 150 g/L COD and 100 g/L TSS. It continuously removes heavy solids like sand, grit, and struvite to prevent accumulation and downtime.
- Handles what other systems can’t
The only Paques reactor engineered to continuously remove inert materials — no manual cleaning or process shutdowns.
(see system comparison) - Designed for real-world wastewaters
Ideal for streams from distilleries, waste-to-energy plants, and manure effluents where solids and grit are unavoidable. - High-rate COD removal
Non-granular anaerobic biomass and plug flow design ensure efficient conversion of organics to biogas, even at extreme loadings. - No dead zones or scum
Advanced hydraulic design prevents mixing problems, short-circuiting, and surface scum, common failure points in conventional anaerobic digesters. - Simple, compact, and operator-friendly
No internal mechanical mixers. All maintenance can be done externally without taking the system offline. - Maximized uptime
Continuous solids and grit removal eliminates process interruptions.
Characteristic : Specification
- COD loading : 25 - 150 g/L
- TSS handling : Up to 100 g/L
- Solids removal : Automatic (sand, grit, struvite, inerts)
- Biomass type : Non-granular, anaerobic
- Footprint : Compact
- Operation : Simple, no mechanical mixing, external maintenance
- Influent and recirculation water are evenly distributed across the top of the reactor through nozzles that also break up any floating scum.
- Biomass moves downflow, creating a stable plug flow regime for optimal COD conversion.
- Heavy solids are collected by a bottom scraper and extracted from the reactor. Optionally, sand and grid are separated from the organic material using a special designed cyclone.
- Biogas produced from the degraded organics exits the top of the reactor and is sent to downstream energy recovery.
- Treated effluent is discharged for further treatment or reuse.
The BIOPAQ® CBD design draws inspiration from principles used in plug flow wastewater treatment. Particularly the plug flow activated sludge process and plug flow aeration tanks widely applied in municipal and industrial treatment.
In a plug flow reactor for wastewater treatment, influent travels in a linear path with minimal back-mixing, ensuring that the wastewater receives consistent treatment as it passes through the system. This flow regime promotes efficient substrate utilization and the lowest possible effluent concentration.
In the BIOPAQ® CBD, the downflow of biomass replicates plug flow behavior, enhancing the biological conversion of organic matter into valuable biogas while maintaining stable reactor performance. This approach optimizes COD removal efficiency and supports the reactor’s ability to handle variable loadings with minimal operational complexity.
BIOPAQ® CBD is the only anaerobic system that combines high-rate organic removal with continuous, automatic solids and grit handling. Where ICX, EGSB and UASB reactors require low solids influent or complex pre-treatment, CBD handles both COD and solids in one compact unit.
Biotech comparison for handling both COD and solids
While competing biological wastewater treatment technologies can handle either high COD or moderate solids/fats, the BIOPAQ® CBD stands out because:
- Continuous grit and heavy solids removal → prevents downtime and manual cleanouts
- Anaerobic biomass plug flow → maximizes COD conversion and TSS destruction
- No need for complex pre-treatment or hydrolysis → lower CapEx and OpEx
Most competing systems require either:
- Careful pre-treatment to avoid solids/grit overload
- Manual or batch grit removal that has accumulated in the reactor