Solar Water Treatment Plant Available
KACO new energy is selling a solar water treatment plant called RayWOx. As a result of recent advances in photocatalytic wastewater treatment technology, the plant centres around a new type of solar receiver that can generate enough process energy from sunlight to break down a wide range of pollutants. Conventional light-based water purifying plants, in contrast, use expensive electrically generated UV radiation. A demonstration plant has recently been inaugurated at the German Aerospace Center (DLR) in Lampoldshausen. RayWOx emerged from the SOWARLA (solar water treatment Lampoldshausen) pilot project, which won the energy globe award in 2008.
Compared to other methods, RayWOx saves about 90 percent of the energy needed to break down pollutants. In addition, the photocatalytic process it uses requires significantly less oxidizing agents to function. The demonstration plant in Lampoldshausen, whose receiver has 240 square meters of surface area, is capable of purifying around 4,500 liters of industrial wastewater of all oxidant pollutants in one to two hours under the given climatic conditions. Sunlight supplies the RayWOx plant with the process energy necessary to eliminate organic and inorganic wastewater pollutants that are difficult to break down. A solar receiver serves as the reactor for the photocatalytic decomposition of substances that degrade water quality. With the help of photocatalyzers, sunlight can be used directly for water purification.
The RayWOx plant is based on an innovative process that was developed as a part of extensive scientific studies and tests. For the SOWARLA project, KACO new energy joined forces with the German Aerospace Center (DLR) and Hirschmann Laborgeräte GmbH & Co. KG. KACO was in charge of the control system, receiver mounting, fluid technology and installation.
The patented solar receiver, which is sold under the name "RayWOx Receiver by Hirschmann", features tubes made of robust and extremely transparent glass to ensure the optimal conversion of incoming solar energy. Contaminated water with added photocatalyzers flows through the glass tubes of the sunlight collecting receiver while a sophisticated control system matches the rate of flow to the amount of incoming solar energy: the volume flow increases with more sunlight and decreases with less sunlight. Once the water achieves the required level of purity, the photocatalyzers are separated and the purified water is channelled away.
Optionally, a PV system specifically configured for this plant is capable of supplying all the energy needed for operation and control. Solar energy can also power the pumps that push the water through the receiver. As a result, the entire plant can function without fossil energy sources. Plus, the operating costs of the RayWOx plant are not impacted by rising energy prices.
Solar water treatment is in demand wherever energy-intensive oxidation processes (photolysis or UV oxidation) are needed. Moreover, this technology can be adapted to suit a variety of applications and hence allows RayWOx to cover the entire spectrum from the pretreatment and treatment of wastewater to its transfer to natural bodies of water. Most organically or inorganically polluted wastewater can be purified. Successful tests have been conducted on contaminants containing antibiotics, radiopaque substances, chlorinated hydrocarbons and the exhaust air scrubber substances used in textile finishing.
Current plans include providing the new plant as an easily-installable and maintenance-friendly module at various locations in temperate or tropical latitudes. The project partners believe that an inexpensive, reliable and efficient solar receiver reactor system will do well in the special wastewater treatment market. RayWOx will be sold by KACO, who sees the sunny Mediterranean countries as the most promising market.
The RayWOx plant won the "World Award for Sustainability" energy globe in 2008 when it was still referred to as the SOWARLA pilot project. SOWARLA managed to beat out 853 competitors in the category of "National Winner". The award was given in the European Parliament and honors the best in sustainable energy projects.