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This paper studies the influence of temperature and of rainfall intensity and the effect of such variations on the treatment efficiencies and on the electrical consumptions in seven medium-large size Wastewater Treatment Plants (WWTPs) in Apulia in South Italy (Bari, Barletta, Brindisi, Lecce, Foggia, Andria and Taranto). It has been observed, in the considered WWTPs, a slight but clear increase of the incoming flow due to the increase in rainfall intensity, which results to an increase of the energy consumption per incoming volume. The impact of the climate change to the incoming flow, during the last five years (2016–2020), has been assessed indicating that an increase in rainfall intensity results to an increase of the WWTPs energy consumptions per wastewater treated volume. More specifically, for a specific WWTP (Lecce) it was found that the electrical consumption increases from 0.36 kw/m3 to 0.51 kw/m3 when the rainfall intensity was increased from 0.8 mm/min to 2.9 mm/min. Some adaption measures have been considered to upgrade the existing WWTP so to mitigate the energy increase and to limit the global effects of climate change. [Display omitted] • As Rain intensity rises, wastewater influx into WWTPs increases. • Rainfall intensity influences negatively electrical consumptions. • BOD removal is lower with increasing annual precipitations. • Temperature influences BOD, COD and SST removal efficiency. [ABSTRACT FROM AUTHOR]

This paper undertakes a comprehensive case study of utilizing municipal solid waste (MSW) collected from thirty-seven different local municipalities and gasified in a gasification plant. The plant is considered to have a 200 ton/h MSW capacity available in the City of Istanbul, Turkey for potential hydrogen production. A thermodynamic analysis of the proposed system is carried out, and its system energy and exergy efficiencies are assessed. The present results indicate that energy and exergy efficiencies for hydrogen production are 57% and 55%, respectively. After the gasification process, the molar percentages of the obtained syngas components are calculated as 19.57 vol%, 18.5 vol%, 0.4 vol%, 7.97 vol%, 7.98 vol% and 45.52 vol% for CO, H 2 , CH 4 , CO 2 , H 2 O and N 2 , respectively. These results are compared to experimental and theoretical studies in the literature, and good agreement is achieved with previous studies. In this plant, the waste may be converted to the hydrogen of 3.014 kg/s via a gasifier, cyclone, catalytic reactor, shift reactors at high-temperature (i.e., 643 K) and low-temperature (i.e., 473 K), and pressure swing adsorption. Image 1 • Developing a municipal solid waste gasification plant for hydrogen production. • Evaluating the plant performance for the wastes in Istanbul. • Studying the possible improvements in the system. • Assessing both energy and exergy efficiencies of the plant. [ABSTRACT FROM AUTHOR]