Management optimisation and technologies application: a right approach to balance energy saving needs and process goals

Energy saving is an ever increasing need not only as a result of the growth in energy global demand and as a result of progressive erosion of supply sources. Another reason is that the environmental impact deriving from energy use is becoming more and more a reason for concern (60% increase of CO₂ emissions over the last 30 years). Rationalizing energy use therefore is a goal in relation to global energy policies. Recently the European Union has developed a plan to reduce energy consumption (20% by 2020): it has issued rules and guidelines targeted at efficiency improvement in different areas such as infrastructure, products, processes and services. Energy saving is therefore a must in wastewater treatment, but one needs to achieve this target without damaging the process. That said, the objective could be reached only by acting contemporarily on technologies and relative selection criteria, designing procedures and, last but not least, Waste Water Treatment Plant monitoring and management practices. This paper focuses on these different areas pointing out opportunities, benefits and possible setbacks in relation to process performance, highlighting the impact of management operations. Starting from simple management variables, it also contains an example concerning the necessary instruments and the coordination of controls needed to regularly evaluate intervention needs and available margins. This paper also deals with the consequences of technologies encouraged as solutions for stable and effective processes, but which are in clear contrast to energy saving goals.