Estimation of a Silica Treatment Reactor by Analyzing Tracer Responses

Abstract

Our previous paper reported the performance tests of the silica-removal from the geothermal brine by the silica treatment reactor. In this study conventional tracer tests were conducted in the reactor in order to obtain mathematical models that explain the transport of the geothermal brine through the reactor. An impulse of NaCl tracer was injected into the reactor together with geothermal brine. The concentration of the tracer was measured as an electrical conductivity at two points in the reactor. The numerical responses calculated by the mathematical model were fitted to the experimental responses. The model assumed the reactor to consist of six domains. One of three types of fluid flow conditions is considered in each domain. These three types of the fluid flowing were the perfect mixing flow, flow with dispersion, and ideal plug-flow. Numerical responses obtained by the model show good agreement with the experimental responses in the reactor. Reaction rate equations were appended to the model in order to estimate the results of the silica-calcium reaction in the reactor. The reaction rate equations and the reaction rate values were made from results in a batch reactor. The model with the reaction rate equation was successfully estimated the results of silica-calcium reaction in the reactor.