Production planning and scheduling problems routinely arise in process industries. In spite of extensive research work to develop efficient scheduling methods, existing approaches are inefficient in solving industrial-scale problems in reasonable time. In this paper we develop a dynamic decomposition scheme that exploits the structure of the problem and facilitates grid computing. We consider the problem of simultaneous batching and scheduling of multi-stage batch processes. The proposed method can be used to solve hard problems on a grid computer to optimality in reasonable time.