The frequentness of serious natural disasters will rise against the background of climate change in the next decades. One of the most severe impacts of natural disasters is the interruption of drinking water supply. Contaminated water causes the death of thousands of people worldwide every year. Mobile waterworks used by aid organizations are sophisticated systems with high demand of energy, skilled personnel and chemicals. They are designed to supply larger communities in the range of (several) thousand people but small and secluded areas can not be reached. The Department of Sanitary and Environmental Engineering (DESEE) at University of Kassel developed a small, transportable and easy to use dead-end membrane filtration unit for basic water supply in cases of natural disasters for small groups in the range of 200 up to 500 people in remote areas, the “WaterBackpack”. Experimental long-term series show that the unit is able to provide water in sufficient quantity and quality for the defined use case. Tests with contaminated surface water revealed, that a minimum flux of around 5 L m−2 h−1 can be kept up over a period of more than two month without any cleaning or maintenance.

Frechen (2012) Membrane technology for municipal drinking water plants in China: progress and prospect, Desalination and Water Treatment, 49:1-3, 281-295, A B S T R A C TThe quality of drinking water from the conventional treatment process is not satisfactory, due to serious pollution of China's surface water. The improvement of the existing water treatment plants is the key to ensure the quality of drinking water in China. Membrane processes are gaining importance in water applications as a result of the advances in membrane technology and the increasing requirements on water quality. This study presents the results of the thorough survey of membrane technology for municipal drinking water plants in China. The survey consists of surveys of literature, membrane manufacturers, and water plants employing membrane technology. We examined the historic perspective of membrane technology and analyzed the membrane market in China. Performance of membrane plants in producing drinking water is investigated based on the survey as well. The results demonstrate that low pressure membrane technologies are employed extensively in China. Water plants with large capacity account for primary market share and drive the annual revenue growth. China will become a fast growing membrane market in the long run and Taihu basin region will continue to be the greatest market for new membrane equipment due to its enormous population and rapid economic growth.

Since the mid-nineties membrane bioreactor (MBR) technology has been introduced to municipal wastewater treatment in Europe. The first MBR plants went into operation performing a conventional mechanical pre-treatment (MPT) without any advanced treatment units. After a short operation period, clogging caused by fibrous substances and hence module sludging was observed. Thus, MPT was upgraded introducing sieves. Several investigations had been carried out to determine the removal efficiency of different sieve units and entire MPT systems. Meanwhile experiences from long-term operation at different MBR sites indicate dependencies between different MPT units, especially between the aerated grit chamber/grease trap and the subsequent sieve unit. Usually the sieve is the final MPT unit and its performance depends on the performance of the upstream MPT units. This report describes and discusses results from a research project at MBR Kaarst-Nordkanal in Germany conducted in 2008 to 2010 by the Water Board of River Erft and the Department of Sanitary and Environmental Engineering. Main focus is addressed for the parameters SS (settable solids) and grease. One major experience is the confirmation of relevant interactions between the grit chamber and the downstream sieve unit. Stable operation of the grit chamber and grease trap is essential to achieve a constantly high removal performance of the sieve unit and therefore the entire MPT stage. In turn, negative impacts on the grit chamber performance from the return flow concept have to be avoided. Finally, it is shown that the appropriate two-dimensional sieve gap size should not go beyond 1 mm when operating hollow fibre membranes.