Our facilities
Membrane manufacturing can be technically challenging and in the last few years the membrane centre has established a new laboratory for purpose of developing new membrane material for gases and liquid.
Facilities at the centre include:
Membrane manufacturing
Membrane manufacturing can be technically challenging and in the last few years the membrane centre has established a new laboratory for purpose of developing new membrane material for gases and liquid. Facilities at the centre include:
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To produce membranes by the phase inversion method, it is necessary to cast consistent films of a known, uniform thickness that can subsequently be immersed in coagulation bath and dried or cured by the appropriate method. Historically, hand operated applicators using casting knife have been used to apply such films, but it is difficult to accurately judge the traverse speed of the applicator and also maintain a constant speed, resulting in an uneven film thickness and variation in membrane performances. The Sheen 1133N Automatic Film Applicator provides a motorised method of driving a range of film applicators. The speed range of this instrument is from 50-500 mm/s.
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The Centre’s custom built polymeric hollow fibre membrane fabrication unit uses a dry-jet, wet spinning technique, where the dope and bore fluid are co-extruded from the spinneret into the air gap with ambient conditions. Once passing through the air gap, the nascent fibres are immersed into a coagulation bath filled with tap water at room temperature. After passing over one wheel-guide, fibres are collected on a take-up drum with a perimeter of 1 meter and ready for further treatments.
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To produce membranes by the phase inversion method, it is necessary to cast consistent films of a known, uniform thickness that can subsequently be immersed in coagulation bath and dried or cured by the appropriate method. Historically, hand operated applicators using casting knife have been used to apply such films, but it is difficult to accurately judge the traverse speed of the applicator and also maintain a constant speed, resulting in an uneven film thickness and variation in membrane performances. The Sheen 1133N Automatic Film Applicator provides a motorised method of driving a range of film applicators. The speed range of this instrument is from 50-500 mm/s.
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Advanced characterisation
Characterisation is an important aspect in membrane research and can be conducted on the membrane material, the fouling material adhering to the surface of the membrane or fluid that is passing through the membrane. Given this, a wide variety of instruments are necessary and the membrane centre as part of UNSW has access to many of them. (See list below for available instruments)
In particular the centre has key partnerships with theÌýÌýandÌý.
SurPASS electro-kinetic analyzer
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Shimadzu TOC-VCSH TOC analyzer
SurPASS Electro-Kinetic analyzer
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- Scanning electron microscopes
- Atomic force microscopes
- Transmission electron microscope
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- Polarising optical microscope
- Infrared and raman spectrometers
- Capillary flow porometer
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- Contact angle analyzer
- Electro-kinetic analyzer
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Custom built submerged MBR unit with multiple membrane cells
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Single hollow fibre unit, with attached microscopeÌý
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- Liquid Chromatography – Organic Carbon Detection (LC-OCD)
- Total Organic Carbon Analyzer
- Inductively Coupled Plasma – Optical Emission & Mass Spectrometers
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- X-ray Diffraction and Fluorensence Instruments
- UV-Visible Spectrophotometer
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Membrane filtration systems
The membrane centre has a suite of filtration apparatus available across the full range of membrane materials, system design, operation type and size.
These include:
Custom built submerged MBR unit with multiple membrane cells
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Single hollow fibre unit, with attached microscopeÌý
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Electrospinning nanofibre machine
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The centre operates over a dozen small scale filtration units which are either manual or semi-automatic in operation and include automated data capture. The units range from 5 – 25 cm2 with module designs able to accommodate flatsheet, hollow fibre and tubular membranes. Modules used include custom in-house units as well as off the shelf modules such as those supplied by Sterlitech and GE Osmonics.
These units are primarily used for fundamental research activities and membrane performance characterisation.
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The centre’s custom built polymeric hollow fibre membrane fabrication unit uses a dry-jet, wet spinning technique, where the dope and bore fluid are co-extruded from the spinneret into the air gap with ambient conditions. Once passing through the air gap, the nascent fibres are immersed into a coagulation bath filled with tap water at room temperature. After passing over one wheel-guide, fibres are collected on a take-up drum with a perimeter of 1 meter and ready for further treatments.
Automated dual-cell high pressure pilot unit
SCADA monitoring system for dual-cell unit
Other units include a tubular ceramic ultrafiltration pilot unit with built-in Labview control system for operation and monitoring whilst on-site, and a automated pilot submerged MBR unit currently operating on-site at a wastewater treatment facility managed by Sydney Water.
Custom tubular ceramic ultrafiltration unit
Pilot MBR unit
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This small scale test unit is used to measure permeation properties of the Centre’s newly developed hollow fibre materials. This high pressure setup uses the variable pressure method which allows for the straightforward determination of membrane permeability and selectivity over a wide range of feed pressure and composition. Permeation testing can be conducted with either pure gas or mixed gases.
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Membrane autopsy facilities
Fouling occurs in all membrane systems and the general operating principle is not how to eliminate fouling but how can it best be managed. This usually occurs in the form of pre-treatment of the feed water, dosing the feed water with chemicals such as acid or base to modify the pH or anti-scalants. Cleaning strategies also form an integral part of fouling management.
Membrane autopsy is a useful technique for determining causes of fouling events in membrane systems. When conducting an autopsy it is usually on the premise that the fouling management process has failed and the aim of the autopsy is to identify the root cause of the fouling event and provide some recommendation on how to correct or manage it.
The UNESCO Centre for Membrane Science and Technology (CMST) has been providing autopsy services on a commercial basis for over 10 years and has conducted over 60 autopsies with clients ranging from large treatment plants to small industry. Since 200x the centre has been developing an autopsy database which stores information gathered from previous autopsies to be used as reference material for further work, thereby benefiting clients.
The standard autopsy is designed to provide a broad overview of the condition of the membrane element, and determine the type and extent of fouling on the membrane surface.
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The centre operates over a dozen small scale filtration units which are either manual or semi-automatic in operation and include automated data capture. The units range from 5 – 25 cm2 with module designs able to accommodate flatsheet, hollow fibre and tubular membranes. Modules used include custom in-house units as well as off the shelf modules such as those supplied by Sterlitech and GE Osmonics.
These units are primarily used for fundamental research activities and membrane performance characterisation.
- Dead-end wet testing and comparison with fresh membranes
- Ìý/ optical emission spectroscopy (OES/AES)
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- Microbial analysis
- Fourier transform infrared spectrometry (FTIR)
- X-Ray Diffraction (XRD)
- Total organic carbon (TOC) analysis
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When a loss of performance is observed, such as
- High permeate conductivity/ low rejection
- High TMP
- High ∆P
- Decrease in product flux
- Increased frequency of cleaning
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Other reasons
- End of trials
- To determine the long term effects of cleaning methods
- After an incident or mishap within the system
Other units include a tubular ceramic ultrafiltration pilot unit with built-in Labview control system for operation and monitoring whilst on-site, and a automated pilot submerged MBR unit currently operating on-site at a wastewater treatment facility managed by Sydney Water.
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The autopsy consists of three steps. Prior to conducting the autopsy, initial information is obtained from the supplier of the membrane including:
- Feedwater and system characteristics
- Normalised performance history
The second step is the autopsy itself. Samples are taken, analysed and the results collected. The final step is the analysis and interpretation of results with reference to the initial information.
The results are also compared to and cross-referenced with the autopsy database. The autopsy data is then stored on the database and used as reference material for further work.
For further information
Please contact Professor Greg LeslieÌý
Ph:Ìý+61 2Ìý9385 6092
E:Ìýg.leslie@unsw.edu.au