In this paper, a novel simulation technique is presented to perform direct numerical simulation (DNS) of fluid flow and mass transfer in dense fluid–particle systems. The fluid–solid coupling is achieved via direct (i.e., implicit) incorporation of the boundary condition (with a second-order method) at the surface of the particles at the level of the discrete momentum and species conservation equations of the fluid. A fixed (Eulerian) grid is utilized to solve the Navier–Stokes equations for the entire computational domain. Dissipative particle–particle and/or particle–wall collisions are taken into account via a hard-sphere discrete particle (DP) approach, using a three-parameter particle–particle interaction model that accounts for normal and tangential restitution, as well as tangential friction. Following the verification of our method using well-known empirical expressions for the Sherwood number, we apply our method to study fluid–particle mass transfer in dense multiparticle systems involving random arrays of stationary particles.