Features - Feasibility, optimisation and costs

MBR OPEX − the theory of running costs

Operational costs in MBRs are marginally higher than those of conventional activated sludge (CAS). Firstly, permeating water through a membrane demands energy. In the case of the immersed technologies (iMBRs) this means that the overall specific aeration demand (SAD) is higher, since air is needed both for maintaining the process biology in the aeration tank and scouring the immersed membrane.

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Membrane operation | Process biology | Feasibility, optimisation and costs

Mechanical shear in membrane bioreactors

In membrane separation systems, it is probably shear which is the most significant parameter for driving the membrane process. Pressure is obviously important for forcing the water through the membrane but shear is arguably the property of the system which largely determines the rate of membrane fouling and so, ultimately, the flux.

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Feasibility, optimisation and costs | Pre-treatment and post-treatment | Water quality and treatability

Arla milk powder factory: membrane bioreactor plant for treating dairy wastewater

In 2012, the Arla milk powder factory in Sweden planned to expand operations. The increased production process generated larger wastewater volumes which the receiving municipal treatment plant was unable to process. Therefore, the dairy decided to build their own treatment plant on site, which needed to be installed within a short period of time and meet strict discharge requirements.

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Feasibility, optimisation and costs | Pre-treatment and post-treatment | Water quality and treatability

Improving MBR flux: Ultrafiltration with a twist

In autumn 2015, after two years of research and development, Pentair brought to market its new ‘Helix’ product. An enhancement to X-Flow tubular membrane technology, Helix features a helically-winding ridge on the inside of the membrane which is designed to tackle cake build-up and enhance flux. The technology has so far been tested on both industrial effluents and municipal wastewater.

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Membrane operation | Feasibility, optimisation and costs | Pre-treatment and post-treatment | Water quality and treatability

Foaming in MBRs: measurement and evaluation

Foaming of conventional activated sludge (CAS) is very common. It may happen during start-up due to the presence of surfactants, with insufficient biomass to degrade them during the early stages. However, this is normally a short-term issue. These foams (from surfactant foaming) are mostly white and can be countered with anti-foamants until there are sufficient biomass developed to degrade them.

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Process biology | Feasibility, optimisation and costs

How much does an MBR cost? The relative cost of an MBR vs an SBR

Operational experience at La Center WWTP in Washington, USA indicates that the cost of MBR technology may be lower than that of a conventional biological treatment process, despite the higher energy demand. La Center is a small city in Clark County, Washington, USA, with a population of 3,100. The wastewater treatment works at the town was originally constructed in 1967

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Feasibility, optimisation and costs | Alternative membrane technologies and applications