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Anaerobic treatment

In the industrial sphere anaerobic  processes are used mainly for pretreatment of highly loaded organic wastewater streams. Using high rate anaerobic biological pretreatment significantly reduces operational costs for ‘high load’ applications due to reduced energy use and  the lower rate of sludge growth compared to aerobic alternatives. In addition, biogas is produced as a cogenerated biproduct. In an oxygen free environment the anaerobic bacteria metabolise most of the available carbon from the polluted wastewater into mostly treated water and methane rich biogas.


As pressure intensifies to reduce medium and long term operational costs, anaerobic processes are becoming increasingly attractive and economical in many applications. However, even though most anaerobic processes remove organic pollutants quickly, with low operational costs, it is often not possible to meet stringent discharge conditions, or water reuse quality without a further aerobic ‘polishing’ stage and subsequent tertiary processes for high quality water reuse.

With this in mind Aquabio has a portfolio of processes to cater for whatever situation our customers are faced with.

To deal with situations where higher rate anaerobic pretreatment processes are required Aquabio has teamed up with Econvert BV to provide cost effective treatment which can then be combined with with our aerobic post treatment and tertiary processes to meet the highest water quality requirement.

Econvert-UASB® (Upflow Anaerobic Sludge Blanket) is designed for the anaerobic wastewater treatment of industrial wastewater. Because of the robust configuration this type of effluent treatment plant is able to handle a large variation and different concentrations of wastewater. This type of anaerobic wastewater treatment plant has been built for over 40 years, all over the world.

Econvert-EGSB® (Expanded Granular Sludge Bed) is designed for the anaerobic wastewater treatment of industrial wastewater with moderate loading rates. Because of the unique settling system this type of effluent treatment plant is able to handle a large variation and different concentrations of wastewater.

Econvert-IR®, Anaerobic Internal Recirculation (IR) Technology is designed for the anaerobic wastewater treatment of industrial wastewater with high loading rates. The two-stage settling enables an internal recirculation. Due to this high COD concentrations can be treated and optimal biological conditions are secured.

Econvert-ECO is specially designed for the anaerobic wastewater treatment of relatively small amounts of industrial wastewater. The unique settling system of the reactor is able to handle a large variation and different concentrations of wastewater. The Econvert-Eco® is the perfect effluent treatment plant for industries discharging 400-2,000 kg of COD per day.

Econvert-Dsulph® is a biological biogas desulphurization unit to remove H2S from biogas. It is suitable to treat biogas originating from for example anaerobic wastewater treatment or from digestion processes. It consists of a biogas scrubber with a bio reactor to regenerate caustic and produce elementary sulphur. It is the best suitable option to treat high concentrations of H2S in biogas.

Pilot Plants : Anaerobic wastewater pilot plants are specially designed to test whether an anaerobic effluent treatment plant is suitable to treat wastewater coming from production process(es). This part of the raw wastewater contains organic compounds that can be tested on its biodegradability.

Aquabio integrates these processes with pre-treatment, aerobic and tertiary processes  to provide the best overall solution to your treatment, reuse and energy cogeneration needs.

Key industry areas are:

–          Food and Beverage

–          Pulp & Paper

–          Flavours & Fragrances

–          Chemical & Pharmaceutical

AnMBR LE™ Anaerobic Membrane Bioreactor Technology

For situations where higher rate and granular sludge based AD processes are not appropriate (e.g. those with very high COD concentrations, high TSS, FOG and salinity) or a customer is looking to maximise organic conversion and gas cogeneration, Aquabio has developed the AnMBR LE™. This is anaerobic treatment combined with Aquabio’s proprietary low energy membrane separation system. The combination results in a number of advantages in circumstances which favour anaerobic treatment with a focus on very high COD removal rates and biogas recovery.

AnMBR LE™ is ideal for applications in:-

–          Distilleries, including pot ale, stillage, spent wash, vinasse etc.

–          Ethanol & biodiesel production

–          Dairy, including high suspended solids (TSS) and fats oil and grease (FOG) streams and whey permeate

–          Starch Slurries

–          Highly concentrated organic wastewater streams with COD concentrations in excess of 15g/l up to in excess of 250g/l, and /or high TSS and FOG

Some key differences from Industrial AD processes are:

–          The process uncouples the Hydraulic and Solids Retention Times – Complete Solids Retention and Control of a Long Sludge Age

–          Greater Tolerance of TSS (and Fats, Oil & Grease but not at Glenmorangie)

–          Increased %COD reduction and Biogas Quality & Yield (Nm3/kgCOD)

–          There is no need for packing media within the bioreactor

–          Improved quality final effluent  & TSS free = Simplified tertiary treatment, e.g. for nutrient removal/recovery & water reuse

–          Low energy biomass separation, with NO Flocculants/Coagulants required (process issues and cost)

–          Simplified pre-treatment

Important Health & Safety considerations are:

–          The AnMBR LE™ membrane system is completely Enclosed Pumped Sidestream  – the External Recirculation  UF Membrane Loop is  NOT exposed to the Atmosphere/Air

–          No gas (e.g. methane, nitrogen) scouring is required for the membranes

–          Retentate and permeate side cleaning is possible in addition to CIP ‘in loop’ cleaning

–          Components are external to the bioreactor which provides convenient servicing and maintenance

Whatever the circumstances Aquabio can design the most appropriate process to meet your goals  – Maximising your return on investment (ROI) and total cost of ownership (TCO) are our priorities.