Experimental Research on the Promotion of Supersaturated Total Dissolved Gas Dissipation by the Use of Activated Carbon

Spill discharge and abrupt water temperature rising may result in total dissolved gas (TDG) supersaturation, which can lead to gas bubble disease (GBD) and even cause mortality of fish. Studies on the mitigation measures about how to promote the dissipation process of supersaturated TDG are essential for the protection of fishes. In this paper, the experimental research about the promotion of supersaturated TDG dissipation by using activated carbon was conducted in static water and stir-induced turbulent water respectively. Supersaturated TDG dissipation processes with different content of activated carbon have been monitored and the dissipation coefficients of supersaturated TDG under various conditions were obtained. The results indicate that the activated carbon can increase the dissipation speed of TDG obviously. The higher the activated carbon content is, the greater the dissipation coefficient is. It can be concluded that the TDG supersaturation problem can be mitigated by introducing activated carbon and enhancing water turbulence when supersaturated TDG occurs in the fish ponds or fish proliferation stations. This study can provide scientific data for the exploration of mitigation measures of supersaturated TDG, which is fundamental for the protection of fishes.