Environmental and Energy Assessment of Municipal Wastewater Treatment Plants in Italy and Romania: A Comparative Study

Abstract

Municipal wastewater treatment plants (MWWTPs) are essential infrastructures in any urban context, but they may be considered as a potential source of greenhouse gas (GHG) emissions and should be coherent with European Union (EU) policy on energy efficiency. This study presents a sustainability evaluation of four Italian and Romanian MWWTPs in terms of energy efficiency and greenhouse gas emissions using Energy Performance and Carbon Emissions Assessment and Monitoring (ECAM) tool software. The obtained results indicated that biogas recovery improved energy performances, while the largest contributions in terms of GHG emissions were in all cases caused by energy consumption and methane produced during wastewater treatment. The Romanian plants exhibited higher GHG emissions, compared to the Italian plants, mainly because of the different values of national conversion factors for grid electricity (0.41 kg CO 2 /kWh for Italy and 1.07 kg CO 2 /kWh for Romania). Two scenarios aimed at enhancing the overall sustainability were hypothesized, based on increasing the serviced population or energy efficiency, achieving significant improvements. A sustainability assessment of MWWTPs should be adopted as a useful tool to help water utilities to introduce low-energy, low-carbon management practices as well as being useful for policy recommendations. Highlights -Sustainability assessment of MWWTPs based on energy consumption and GHG emissions -Biogas valorization leads to lower energy consumption -Higher GHG emissions caused by energy consumption and methane production -Different scenarios were hypothesized to improve sustainability -National conversion factor, linked to local energy mix, played a key role

Sustainable Alternative Routes versus Linear Economy and Resources Degradation in Eastern Romania

“…Sustainable wastewater management practices should replace direct discharges of untreated wastewater into water bodies and should reduce GHG emissions from the water sector [67]. Some water systems in Romania have water losses of more than 50% of the total water extracted with higher energy demands [68].…”

Real-Time Monitoring and Static Data Analysis to Assess Energetic and Environmental Performances in the Wastewater Sector: A Case Study

“…With reference to a timeline of 5 years, from January 2016 to December 2020, data were collected as average or total values at a monthly frequency and concern the main control variables of the purification process, in particular: total energy consumption of the facility; average pollutant load entering and leaving the plant, expressed in terms of COD, BOD and TSS; total wastewater flowrate per month. Equivalent emissions expressed in terms of tons of oil and CO 2 , associated with the electricity consumption of the facility, were inferred using the following conversion factors: 0.187 tons of oil equivalent (toe) for each megawatt-hour of electric consumption (MWh el ), according to D.Lgs 102/2014 as amended [19] 2014), and 0,411 tons of CO 2 equivalent for each MWh el , according to Fighir, et al [20].…”

Review of Methods for Assessing the Impact of WWTPs on the Natural Environment

“…Among the processes, energy is required for mechanical, biological and chemical treatment and disinfection. There is a demand mainly for electricity but also for gas and other fuels [17]. Energy consumption is associated with the depletion of non-renewable natural resources.…”