Treatment Processes

Anaerobic Membrane Bioreactor (AnMBR): Selection & Operating Framework

Treat anaerobic membrane bioreactors as a distinct process family: their potential resource-recovery advantages come with biological stability, gas-safety, fouling and post-treatment questions that must be resolved for the actual wastewater and end use.

Scope and limitation. This guide introduces submerged and sidestream AnMBR selection and operating considerations. It does not establish loading, flux, temperature, cleaning, gas-handling, safety zoning, emissions or discharge requirements for a specific project.

Membrane separation changes anaerobic process boundaries

AnMBRs couple anaerobic conversion with membrane solids separation, which can retain slow-growing biomass while producing a low-solids permeate. Their suitability depends on wastewater strength and variability, temperature, dissolved methane, nutrient and downstream-treatment needs, membrane configuration, energy balance, gas management and operator capability. Public reviews describe both the potential and the remaining scale-up and operating challenges. [1]

Selection questionEvidence to developDecision boundary
Is anaerobic conversion suitable?Representative influent characterization, biodegradability, variability, inhibition/toxicity, temperature and downstream objective.Do not assume an aerobic MBR design basis transfers to anaerobic operation.
Which configuration is plausible?Membrane supplier information, hydraulics, fouling-control concept, maintainability, gas handling and energy model.Compare configurations on the same lifecycle and safety basis.
How is stability assessed?Approved process indicators, laboratory programme, gas data, alkalinity/VFA context and load history.Use site-specific process support for instability or toxicity; do not dose or adjust loading from a generic ratio.

Plan gas and post-treatment from the outset

Biogas can be a resource and a safety hazard; methane, hydrogen sulfide, oxygen ingress and confined-space conditions require engineered controls. AnMBR permeate may also require nutrient removal, polishing, disinfection or other treatment according to the discharge or reuse objective. The membrane barrier does not remove the need to define those treatment-train and regulatory interfaces.

Related resources. The MBR Quick Sizing, Flux, Area & Train Sizing, and Energy & Operating Cost calculators are aerobic-MBR-oriented screening tools unless their assumptions are explicitly validated for the anaerobic configuration. They do not model biogas safety, dissolved methane or AnMBR biological stability.
Gas and process-safety boundary. Methane and hydrogen sulfide hazards, pressure systems, gas treatment and confined spaces require qualified engineering, monitoring and the applicable site safety plan. Do not infer a gas-handling design from this guide.

Sources and revision note

This guide is an educational engineering reference prepared from public technical literature and operator-practice material. It does not replace an approved plant procedure, permit condition, process validation, laboratory programme, control-system standard, gas-safety plan, or membrane manufacturer instruction. Last reviewed: August 22, 2026.

  1. Kanafin et al., Anaerobic Membrane Bioreactors for Municipal Wastewater Treatment.
  2. The MBR Site, Anaerobic MBR Process Control.
  3. Ferrer et al., Design Methodology for Submerged Anaerobic Membrane Bioreactors.