Window cleaning[edit]

An increasingly popular method of cleaning windows is the so-called "water-fed pole" system. Instead of washing the windows with detergent in the conventional way, they are scrubbed with highly purified water, typically containing less than 10 ppm dissolved solids, using a brush on the end of a long pole which is wielded from ground level. Reverse osmosis is commonly used to purify the water.^[15]

Landfill leachate purification[edit]

Treatment with reverse osmosis is limited, resulting in low recoveries on high concentration (measured with electrical conductivity) and fouling of the RO membranes. Reverse osmosis applicability is limited by conductivity, organics, and scaling inorganic elements such as CaSO4, Si, Fe and Ba. Low organic scaling can be used two different technology, one is using spiral wound membrane type of module, and for high organic scaling, high conductivity and higher pressure (up to 90 bars) can be used disc tube module with reverse osmosis membranes. Disc tube modules was redesigned for landfill leachate purification, what usually is contaminated with high organics. Due to the cross-flow with high velocity is given by a flow booster pump, what is recirculating the flow over the same membrane surface between 1,5 and 3 times before is released as a concentrate. High velocity is also good against membrane scaling and allows successful membrane cleanings.

Power consumption for a disc tube module system[edit]

Disc tube module with RO membrane cushion and Spiral wound module with RO membrane

Desalination[edit]

Areas that have either no or limited surface water or groundwater may choose to desalinate. Reverse osmosis is an increasingly common method of desalination, because of its relatively low energy consumption.