M A N U F A C T U R E R S

MITSUBISHI/GRONTMIJ/WATEC

Main player in MBR market Mitsubishi Rayon CO., established in 15133 <w a producer of rayon staple, manufactures and markets a wide rattle of acrylic, polyester, acetate and otherjibres as well as methyl methacrylate, ABS and MBS resins. Particular emphasis is placed on hujh-performance materials and products such as carbon/ibres, composite materials, optical jibres and membranes. Lastyear company sales amounted to three billion USD, with a total 0/4.500 employees. Mitsubishi Rayon Corporation houses manufacturing, engineering and research and development.

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The hollow fibre membrane is produced by a sophisticated melt spinning and drawing process from a polyethylene material. Regarding quality control, the membrane production facilities have been awarded the ISO9002 standard and quality control is conducted accordingly.

The actual production capacity of the hollow fibre membrane factory is approximately two million kilometres per annum. MRC has the financial and technical ability to rapidly increase the production capacity of its factories to meet increasing membrane demand.

MRC is continuously conducting research and development for its products. R&D is focussed on the improvement of the present membrane as well as on the development of totally new membranes (including other materials]. Product improvements have been and will be introduced regularly according to market demands and technological developments. A new module configuration and improved membrane is expected to be launched early

The engineering part of Mitsubishi Rayon provides water and wastewater treatment systems. Engineering works closely together with Manufacturing as well as Research and Development to meet market needs in water treatment and environmental protection (aqua-sustainability), primarily in the purification and treatment of drinking water, process water and wastewater.

History Filtration equipment applied membrane

technology developed by MRC was put into practical use in about 1980. The application

has been expanded widely and now includes filtration of active sludge as in membrane bioreactors. Since the early nineteen nineties, the use of Mitsubishi Sterapore membranes in membrane bioreactor applications is continuously increasing.

Membrane bioreactor For membrane bioreactor applications a

polyethylene hydrophilic hollow fibre membrane is used: the Sterapore membrane. The pore size is 0.4 micron, the outer diameter 540 micron and the inner diameter 360 micron. It is a clean, hygienic and safe membrane, as it contains no solvents and plasticizers.

Membrane unit of Mitsubishi.

The hollow fibre membrane is a very tough membrane that has a high tenacity and strong resistance to bending fatigue. In addition, it is not affected by any micro­organisms and acids, alkali and irradiation hardly have any affect at all. The packing density and volume efficiency is superior.

The fibres are assembled in membrane elements, which are connected into modules (see photograph). An industrial, cost efficient construction method is applied to the modules and the membrane elements,

Grontmij participates in Beverwijk Grontmij Water & Waste Management is a leading player in rhe field of environmental engineering. Expert in all aspects of water management: from drinking and process water supply to sewage and industrial wastewater treatment. Since the early nineteen nineties Grontmij is active on the MBR market. Grontmij has extensive experience with MBR projects and provides a full range of activities ranging from feasibility studies to contracting and operation. Therefore, Grontmij provides not only engineering and technologicalexpertise, but also manages integrated projects and can supply full process guarantees for governmental agencies and industrial clients.

At the Beverwijk trials, Grontmij supports MRC in design, operation, optimisation and evaluation of the Mitsubishi pilot tests. The tests are focussed on the technical development and optimisation of the Mitsubishi membranes for a MBR system under Dutch circumsrances. In the Netherlands, large flow fluctuations and low ambient temperatures are present and Nitrogen and Phosphorus removal is required. However, rather than membrane and biological performance, the success of MBR systems for the municipal market is dominated by investment and operational costs, operational risks, guarantees and finally the need for higher effluent standards.

The developments of the last decade have shown to result in a wide range of MBR-applications, diversity in membrane properries and system configurations. Grontmij in co-operation with a variety of national and international research institutes, consultants, membrane suppliers and funding agencies is involved in the further developmenr of MBR technology.

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Watec: industrial MBR Watec is a Dutch company that focuses mainly on design and realisation of MBR-plants for treating smaller industrial wastewater at companies in Europe. In this growing and very competitive market MBR-systems are superior for reasons of performance and controllability, both technical and financial.

Up to now Watec has realised four plants in The Netherlands and Belgium, all located at tank cleaning companies. Wastewater of these companies sometimes is very difficult to treat. Pre-treatment with dissolved air flotation may be necessary and Watec also executes this. A good example of the MBR-plants realised by Watec is the transport and tank cleaning plant ofNijhof-Wassink in Rijssen, with some 250

tank-cars one of the leading transport companies in The Netherlands. A second MBR-plant will be realised soon at the Nijhof-Wassink site in Poland. In addition, Watec is working on two more plants on industrial waste water in The Netherlands.

In cases of difficult waste water, Watec prefers to do pilot tests on location. Not only will this lead to a more precise and cost-effective plant, it will also give our clients confidence in the new and innovative MBR-technology. Watec owns two fully automated pilot plants for doing test-runs on location. All full-scale plants realised so far have been pilot-tested and clients are very satisfied with this approach.

Mitsubishi M. Shinohara phone: 00813 3210 6908 Ms. C. Willhoff phone: 0049 2114397396

Grontmtj Woter and Waste Management Bert Geraats or Rosier van Kempen phone: +31 (0) 30 694 3210 fax: +31 (0) 30 695 63 66 e-mail: w&rdebiltgJgrontmij.n!

Watec Harry Bosgoed or Dick Versteeg phone: +31 (0] 184 60 82 82 fax: +31 (0) 184 60 82 80 e-mail: in/o@watec.nl

Visit to a Mitsubishi MBR installation/or wastewater treatment in... (photo: DHV Water].

yielding low maintenance requirements. The modules are submerged in an aeration tank containing the biological sludge. Treated wastewater is removed by suction from the outside into the inside of the fibre. The modules can be stacked up to 4.5 meters, which allows for efficient use of air and floor space.

The membranes are kept clean by a combination of cleaning by scrubbing of air bubbles, relaxation, back-flushing and a mild chemical treatment.

Operation strategy MRC's basic approach and reasoning is

that mild and stable operation, process stability, reliability and costs per treated m' of wastewater are of primary importance to the client. Integration of biological and membrane operations are considered as a key points in successful application. Rather than trying to cope with high flux and flux variations directly, the membrane area can

be increased to secure mild and stable operating conditions and long life span. MRC has a flexible approach to cost matters, taking market requirements into account.

References Most of the MBR references can be found

in Japan. MRC is the dominant player in Japan in collaboration with Japanese engineering companies. From 19512 to 2000 approx. 700 references have been realised. A third of the references apply to treating domestic wastewater. Applications can be found in a wide range of different types of industries. MRC operates globally.

Grontmij made it possible for MRC to join the pilot research in Beverwijk. MRC is involved in similar pilots in Japan and the US.

Industrial MBR projects in the Netherlands are realised by Watec, in Belgium by ATH. f

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