In addition to providing a dependable, locally controlled water supply, water recycling provides tremendous environmental benefits. By providing an additional source of water, water recycling offers ways to decrease the diversion of water from vital, sensitive ecosystems, thus ensuring that sufficient water flows to plant, wildlife, and fish habitats—allowing them to live and eproduce. A lack of adequate flow, as a result of diversion for agricultural, urban, and industrial purposes, can cause deterioration of both water quality and ecosystem health. Water users can fulfil their demands by using recycled water, which can free substantial amounts of water for the environment. Other environmental benefits include a reduction in wastewater discharges and reducing or preventing the potential for pollution.
Recycled water can save energy. As the demand for water increases, more water is extracted, treated, and transported, sometimes over great distances, which can require a lot of energy. Also, if the local source of water is groundwater, as more water is removed, the water level drops, which in turn increases energy needed to pump the water to the surface. Recycling water onsite or nearby reduces the energy needed to move water longer distances or to pump water from deep within an aquifer.
Tailoring water quality to a specific water use also reduces the energy needed to treat water. The water quality required to flush a toilet is less stringent than the water quality needed for drinking water and requires less energy to achieve. Using recycled water that is of lower quality for uses that do not require high-quality water saves energy and money by reducing water or wastewater treatment requirements.
Ultra filtration is used in certain industries to accommodate reuse. Therefore, cost justification for ultra filtration can include initial capital investment, membrane fouling and replacement costs and also additional pre treatment of feed water to prevent excessive damage to the membranes in the Ultra filtration Units. Some of the benefits, however, remain more intangible.
Industries that consume large volumes of water or discharge highly toxic effluent are candidates to employ ultra filtration for water reuse. These include the chemicals, steel, plastics & resins, paper & pulp, pharmaceutical and the food & beverage industries, including soft drinks & canned foods, as well as power, water & wastewater treatment plants and others.
Ultra filtration is used to recycle flow or add value to later products and more. In many cases ultra filtration (UF) is used for pre filtration in reverse-osmosis plants to protect the reverse-osmosis process. Ultra filtration is an effective means of reducing the silt density index of water and removing particulates that can foul reverse osmosis membranes. Ultra filtration is frequently used to pre treat surface water, seawater and biologically treated municipal water upstream of the reverse osmosis unit.
