Membrane technology can be utilised for the high purification and desalination of water. However membrane filtration processes are commonly impeded by membrane fouling, which can lead to flux decline and an overall reduction in separation efficiency within the process. Therefore the aim of this research study was a comprehensive investigation of the issue of biofouling on industrial RO membranes through molecular biology techniques, characterisation of surface charge of foulant bacteria and RO membrane surface and AFM imaging and force measurements on clean and fouled membranes for the determination of adhesion force and micromechanical properties. The laboratories within Gwangju Institute of Science and Technology, South Korea and Swansea University, Wales were equipped for the scope of this research work. Research focused on the extraction of microbial DNA obtained from fouling layers on the surface of Reverse Osmosis Membranes obtained from the Fujairah Water and Power Plant, UAE. The use of the culture independent method of the molecular technique based on the 16S rDNA sequence and constructed gene libraries, was then used to determine the bacterial species that caused significant fouling on the RO membrane. Four bacterial species isolated from the fouling layer from the RO membrane were characterised in terms of electrophoretic mobility and zeta potential to determine the cell surface charge within various industrial relevant environments for the elucidation of cell adhesion mechanisms to the membrane surface. AFM images of virgin and fouled membranes were obtained and analysed to reveal the roughness of the surface which could influence fouling and the surface charge of the membranes were measured through the method of streaming potential at various industrial relevant environments to further elucidate the mechanisms of cell adhesion to the membrane surface. Force measurements were performed to reveal the adhesion force and elasticity values of virgin, process fouled and purposely fouled with the four bacterial isolates, to determine process behaviour in various environmental conditions. Through this research and future work, it is hoped that a rational strategy for economic and effective cleaning processes will be developed which will maintain efficient membrane operation and prolong membrane life, thus enabling the reduction of operating costs of such processes.

Planetens resurser utnyttjas inte på ett ansvarsfullt sätt och för att uppnå en hållbar utveckling behöver en förändring ske i hur dessa resurser konsumeras och produceras. Ett företag som arbetar för att använda sina resurser mer effektivt och minska sin negativa miljöpåverkan är Aurobay Sweden AB.  Aurobay tillverkar drivlinor för interna hybrid- och förbränningsmotorer och använder skärande bearbetning i delar av sin produktionsprocess. Till den skärande bearbetningen används skärvätska vilket behöver filtreras för att kunna återanvändas. Företaget använder en filtreringsprocess med filterduk för att separera spånor från skärvätskan. Aurobay vill minska sin förbrukning av filterduk och skaffa en bättre förståelse för hur företagets filtreringsutrustning kan nyttjas bättre i framtiden.  Ett experiment genomfördes för att utvärdera hur en förändring av cykeltid påverkade mängden spånor som transporterades bort från filtreringsutrustningen. Resultatet visade att mätningar behöver genomföras under en längre period eftersom externa faktorer kan ha en påverkande effekt. Efter en nulägesanalys av utnyttjandegraden på några av företagets filtreringsutrustningar kunde det konstateras att den kunde vara så låg som 15 %. Genom att öka cykeltiden som filtreringsutrustningarna filtrerar kan utnyttjandegraden höjas och förbrukningen av filterduk minskas med 26 %. Utan ytterligare investeringar kan Aurobay minska kostnaderna för att köpa in ny filterduk och hantering av den förbrukade. / The planet’s resources are not being utilized responsibly, and to achieve sustainable development, changes are needed in how these resources are consumed and produced. Aurobay Sweden AB is one such company working to use its resources more efficiently and reduce its negative environmental impact.  Aurobay manufactures drivetrains for internal hybrid and combustion engines and for some of its production process machining is used. Cutting fluid is used in this machining process and it needs to be filtered before reuse. Aurobay utilizes a filtration process with filter media to separate chips from the cutting fluid. Aurobay aims to reduce its use of filter media and seeks to gain a better understanding of how the company’s filtration equipment can be optimized for future use.  An experiment was conducted to assess the impact of changing the filtration equipment’s cycle time when it comes to remove chips from a filtration process. The results indicated that measurements need to be conducted over a longer period as external factors may have an influencing effect. After an analysis of the utilization rate on some of the company’s filtration process equipment, it was found that utilization rates could be as low as 15 %. The utilization rate can be improved by increasing the cycle time which the filtration equipment operates, and the consumption of filter media can be reduced by 26 %. Without additional investments, Aurobay can reduce the costs for both purchasing new filter media and removal of the old one.