Hydrodynamic limit for two-species exclusion processes

We consider two-species exclusion processes on the d-dimensional discrete torus taking the effects of exchange, creation and annihilation into account. The model is, in general, of nongradient type. We prove that the (charged) particle density converges to the solution of a certain nonlinear diffusion equation under a diffusive rescaling in space and time. We also prove a lower bound on the spectral gap for the generator of the process confined in a finite volume. (C) 2010 Elsevier B.V. All rights reserved.