Kinetics barite precipitation

The behavior of silica and barite precipitation from the hydrothermal solution which mixes with cold seawater above and below the seafloor based on the thermochemical equilibrium model and coupled fluid flow-precipitation kinetics model is described below. 

However, as already noted, the barite content in Kuroko ore inversely correlates to the quartz content and the occurrences of barite and quartz in the submarine hydrothermal ore deposits are different. The discrepancy between the results of thermochemical equilibrium calculations based on the mixing model and the mode of occurrences of barite and quartz in the submarine hydrothermal ore deposits clearly indicate that barite and quartz precipitated from supersaturated solutions under non-equilibrium conditions. Thus, it is considered that the flow rate and precipitation kinetics affect the precipitations of barite and quartz. 

Christy, A.G. and Putnis, A. (1993) The kinetics of barite dissolution and precipitation in water and sodium chloride barines at 44-850°C. Geochim. Cosmochim. Acta, 57, 2161-2168. 

Given a specific application, we might also include precipitation kinetics in our calculations, as described in Chapter 16. Wat et al. (1992) present a brief study of the kinetics of barite formation, including the effects of scale inhibitors on precipitation rates. For a variety of reasons (see Section 16.2), however, it remains difficult to construct reliable models of the kinetics of scale precipitation. 

Precipitation kinetics of salts such as barite (BaS04) has been studied to prevent the formation of scale (BaS04, CaS04 2H20) in the pipes for the transportation of oil and geothermal water. 

Shikazono et al. (2012) used precipitation kinetics-fluid flow model to explain the mode of occurrences of barite, quartz and anhydrite in Kuroko deposits (submarine hydrothermal polymetallic sulfide-sulfate massive deposits in Japan). 

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