Anaerobic Membrane Bioreactor

Download the ADI-AnMBR brochure.

One of the key components to any anaerobic treatment system is effective separation of treated water from the biogas generated by the anaerobic digestion process while ensuring the bios is retained within the reactor. The need for effective gas/liquid/solid separation has led to the development of numerous anaerobic technologies, each with their own unique separation system. However, none of these systems can match the performance of the ADI-AnMBR.

The ADI Anaerobic Membrane Bioreactor, or AnMBR process, based on award-winning technology developed by Kubota Corporation of Japan, is a form of high-rate anaerobic contact process that uses a submerged membrane barrier to perform the gas/liquid/solid separation and reactor biomass retention functions. This near-absolute barrier to solids ensures efficient system operation, even under high organic loading and intense mixing scenarios. Since gravity settling is no longer required, higher organic loadings and mixing intensities can be employed than with other anaerobic technologies, increasing organic removals, improving biogas production, reducing system footprint and allowing for treatment of wastewaters with very high suspended solids, such as distillery or ethanol stillages, septage, and even municipal solid waste. The ADI-AnMBR achieves all this while maintaining the highest-quality anaerobic effluent in the marketplace.

The submerged membrane technology utilized in the AnMBR is the same industry-leading technology utilized by Kubota and its partners in their aerobic MBR systems and thus has a huge body of operating experience, long-life and high performance. The membranes have been employed in full-scale AnMBR systems since 2000 and in full-scale trials since the mid-1990s. With over a dozen installations in Japan and the USA, the technology is now gaining acceptance by a wide range of industries, consultants and end-users.

In the AnMBR, the high-performance membrane air scour cleaning that eliminates the need for recovery cleanings and provides the longest cleaning intervals is slightly modified. Instead of air, biogas generated in the anaerobic digestion is utilized to continually clean the membranes during operation. This gas scour system has proven to be nearly as effective as the aerobic MBRs’ air scour process and results in typical maintenance cleaning intervals of one to three months in the AnMBR—less frequent than many competitors’ aerobic MBRs!

Some of the advantages of ADI-AnMBR technology over other anaerobic systems include:

• Higher loadings due to complete retention of biomass and higher mixing/contact intensities possible
• Smaller footprint
• Superior quality, solids-free anaerobic effluent
• More stable process due to elimination of biomass loss
• Can operate at thermophilic temperatures (better removals, more biogas, reduced sludge production), yet avoid common operating problems at thermophilic temperatures (biomass loss, unstable operation)
• Can handle high concentrations of influent TSS and fats, oil and grease (FOG) while maintaining high organic loading rates.

The ADI-AnMBR can be utilized to treat essentially any wastewater amenable to anaerobic treatment, but is most applicable to very strong, concentrated wastes, solid and semi-solid wastes and slurries, and wastewaters with poor settling characteristics, including:

• Distilleries
• Wineries (wastewater and pomace)
• Fuel and food-grade ethanol production stillages
• Food processing wastewaters
• Chemicals production