Qatar University research team develops new approach to test clogging in membrane bioreactors
A research team from the Gas Processing Center (GPC) at Qatar University College of Engineering (QU-CENG), with external collaborators from Public Works Authority Qatar (Ashghal) and Qatargas has developed a method for testing clogging of membrane bioreactors.
The team includes GPC Environmental Engineering Chair Prof Simon Judd, GPC Post-doctorate Researcher Dr Pompilia Buzatu and CENG Department of Chemical Engineering Co-Principal Investigator Prof Hazim Qiblawey.
Themed ‘Membrane bioreactor technology: a new approach for improved process robustness’, the work has been conducted as part of the National Priorities Research Program (NPRP) project.
The team studied municipal and industrial wastewater sludge samples from plants at Lusail and Ras Laffan. They used a bespoke test cell designed to allow direct viewing of the membrane channel for clogged solids.
Sludge from existing operating MBRs has been introduced into the cell and their clogging behaviour has been observed directly. The image of the clogged membrane channel was then translated to a number indicating the extent of the clogging. The study revealed that both ways in which the membrane clogs the channels and the amount of clogging produced depends on the source of the sludge and the process operating conditions. Remedial measures to avoid problems with membrane permeability recovery have been recommended.
Prof Simon Judd said: ‘MBRs are considered the technology of choice for advanced biological treatment of wastewater where space is limited and/or where treated water of high quality such as for irrigation is required. A technical challenge is the loss of membrane permeability, or the reduction of flow through the membrane. This is conventionally attributed to membrane surface fouling – a very well-studied topic – by dissolved organic material in the mixed liquor (or sludge) providing the biological treatment. This is one of only a handful of studies which have quantified clogging, and the only one to use direct observation as the method.’