Ricerc@Sapienza

Two-phase pressure drops in a mini-tube, in transition flow and subcooled boiling, are analyzed in the present paper, with the support of an experimental data set provided by ENEA with their BO.E.MI.A. test section. The methodology can be applied to different fluids according to similarity criteria. Single phase, subcooled and saturated conditions have been analyzed. The Reynolds number in the experiments was mainly in the transition zone between laminar and turbulent conditions, therefore a third order interpolation curve of the friction factor has been employed.

Natural and waste waters pollution by nitrates is considered a major environmental problemdue to the possible consequences on human health and on water bodies through eutrophi-cation phenomenon. Hazelnut shell were employed as packing material in a large lab-scalecolumn for the removal of nitrate from wastewaters, comparing the process performanceswith those obtained in batch system. A nitrate removal efficiency up to about 67% wasobserved in batch mode at low pH and with a sorbent mass concentration of 8 g/L with0.5 mm size.