Pore-scale investigation on reactive flow in porous media with immiscible phase using lattice Boltzmann method.

Reactive flow happens during carbonate rock acidification. In the present study, carbonate rock dissolution process is investigated by lattice Boltzmann method at pore scale. The two immiscible fluids flow, solute transport and heat transfer are solved by the Shan-Chen multiphase multicomponent lattice Boltzmann model, mass transport lattice Boltzmann model and multicomponent thermal lattice Boltzmann model, respectively. The solid phase is updated by Volume of Pixel method. The results show that the immiscible phase has negative effect on dissolution, while positive effect on acid penetration. The immiscible phase effect is influenced by the inlet velocity, porous media porosity, surface wettability and temperature. The increasing inlet velocity and temperature accelerate the dissolution rate, but decrease the degree of immiscible phase suppression on dissolution. The surface wettability impact on dissolution process is influenced by the immiscible phase distribution. The porosity affects the degree of immiscible phase suppression on dissolution process slightly. • Pore-scale reactive flow in porous media is investigated by LBM. • The immiscible phase promotes the solid dissolution before a certain time. • The solid dissolution and acid breakthrough rates increase with increasing inlet velocity. • The increasing temperature accelerates dissolution rate but reduces immiscible phase influence degree. [ABSTRACT FROM AUTHOR]