Author(s): Havard Hartvig Gundersen; Wolf Ludwig Kuhn; Bjorn Winther Solemslie; Jean-Yves Hihn; Ole Gunnar Dahlhaug
Linked Author(s): Wolf Ludwig Kuhn
Keywords: Total dissolved gas supersaturation; Mitigation; Environmental measures; Liquid-gas mass transfer; Aeration
Abstract: Increased total dissolved gas (TDG) saturation levels in rivers downstream hydropower plants are an increasing problem in Norway and other hydropower-utilizing countries (Li et al., 2022). Being associated with flooding, TDG supersaturation causes potentially mortal gas bubble disease in fish and other aquatic lifeforms (Botelho et al., 2017; Zarfl et al., 2019). Mitigation measures focus mostly on prevention of air entrainment, which in combination with increased ambient pressure leads to dissolution of gas in the liquid phase. Where air entrainment cannot be prevented, the prevalent solution to-date is adjustment of the power plant’s operation. This project focuses on offering different mitigation strategies by using technical means to degas the water exiting the hydropower plant in case of TDG supersaturation. In the present case, aeration by gas bubbling is used to enhance the liquid-gas mass transfer of flowing water in a laboratory test rig.
Year: 2024