“Cycle closure” in waste management: tools, procedures and examples

Green Chemistry is a philosophy of chemical research and application that encourages the design of appropriate products/ processes in order to minimize the use and production of hazardous chemicals. Green Chemistry involves the application of new, milder synthetic pathways, the avoidance of toxic solvents’ use, the use of alternative sources of raw materials, the prevention of pollution, the design of environmental friendly products, the protection of workers’ health and the reduction of energy consumption. Wastewater treatment plants consume significant amounts of energy for collection, transport, processing and final disposal of water and by-products. Attempting to reduce the respective energy costs, energy recovery is an attractive alternative, as liquid wastes considered to contain significant amounts of energy. In addition, many technologies have been developed recently to recover useful materials from liquid wastes (phosphorus is a typical example). In 2012, the EU-28 Member States discarded 2.5 billion ton of wastes, of which 4% was classified as hazardous, hence immediate and environmental friendly solutions are requested. The need to record and report the Environmental Footprint of an enterprise/industry becomes imperative. The adoption of green practices can act as catalyst to improve the processes of an enterprise, to reduce the cost of products and to maintain an environmental responsible attitude.