Features - Feasibility, optimisation and costs

Cost comparison of full-scale water reclamation technologies with an emphasis on membrane bioreactors

The authors consider cost information from installations across Spain, and compare this with corresponding information for the more conventional activated sludge (CAS) technologies. The CAPEX and OPEX − capital and operating expenditure − information was used to generate cost curves as a function of flow capacity or population equivalent (p.e.) for both technology types.

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Feasibility, optimisation and costs

A comparative techno-economic-environmental assessment of full-scale CAS vs MBR technologies

Although a number of studies have compared the MBR system performance with that of the conventional or classical activated sludge (CAS) process in treating municipal wastewater, none have attempted a simultaneous comparison of their environmental, techno-economic and social acceptance aspects.

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Feasibility, optimisation and costs | Alternative membrane technologies and applications

Reducing process aeration energy consumption in MBRs

MBRs use more energy compared with classical activated sludge (CAS) because the aeration requirements are greater. Aeration is needed both for the biological and membrane tanks for degrading the organics and scouring the membrane respectively. Typically, aeration energy consumption accounts for 70–80% of total energy used for the municipal wastewater treatment process, with 40–60% consumed by the process biology.

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Membrane operation | Process biology | Feasibility, optimisation and costs

Reuse of dairy wastewater treated by membrane bioreactor and nanofiltration: technical and economic feasibility

A study carried out by Andrade and co-authors assessed the viability of a two-stage membrane bioreactor−nanofiltration scheme (MBR−NF) for treating dairy wastewater. Of key concern was the quality of the treated water with respect to its potential reuse and the overall cost of the scheme.

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

Kunming Underground MBR: a Chinese case study

China features many of the largest municipal wastewater MBRs in the world. Apart from their capacity, some also are ambitious in their construction. The below-ground installation at Kunming City, commissioned in 2012, is one such example. At an ADF (average daily flow) capacity of 150,000 m3/d and a peak daily flow of 195,000 m3/d, it is a substantial plant.

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

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