In arid and semi-arid areas, water supply is a permanent problem due to low precipitation, high evaporation, aquifers over pumping, over-population, tourism and higher living standards. The aforementioned island is not an exception, since the water problem has been progressively increased despite the construction of several dams and hydraulic projects. Taking this into account, the recycling of unsuitable water can be an important part of a comprehensive water cycle management, as saving drinking water has the same effect to water resources as achieving additional water supply from new and costly projects. From all the available sources of non-potable water, grey water (water from bathrooms, showers, washbasins, washing machines, etc.) is available on a daily basis and can be about 45% of the total household water consumption, so it can be used for non-drinking applications after recovering.
Being aware of the island situation, Hydranos Ltd developed a decentralized system for treating greywater that can be independently installed in households and other civil infrastructures. The project was carried out with the purpose of promoting the use of this system in Cypriot installations, and was co-funded by the European Union within the CIP Eco-Innovation initiative. The project consortium was composed of two Cypriot companies: Hydranos Ltd (which acted as coordinator) and LML CBA (Conquest Bussiness Advisors), a consultancy company. The project arose on promoting the use of the Cyprobell technology by making leaflets and contacting engineering companies and policy makers.
The developed Grey Water Recycling System comprises a collection tank to balance out the substantial variation in flow and composition of the grey water over the day, and a treatment tank where chemical stabilising takes place. Considering that the system can be adapted to every customer’s needs in terms of size, cost and degree of automation, the intermittent pump rate from the treatment tank is in each case timed to give a total volume matching the user demand. The treated water can be pumped to a third tank (reuse tank) or be used directly for irrigation purposes. In general terms, the purified water is not potable, and can be used, in example, for irrigation or toilet flushing.
This technology is already fully operative (level 9 in the TRL scale), and can be used mainly in households where grey water can be reused for irrigating or flushing. Furthermore, this system has been applied to large-scale infrastructures like hotels, schools and army camps. By reusing waste water, the hydric demand of high quality water can be dedicated solely to potable water. After a medium-scale implantation of the technology in this island, the next objectives of the consortium will be to export the system to other countries with water scarcity (Spain, Italy, Magreb, Greece, Turkey, etc.).