The scheduling of batch chemical processes has been the focus of a substantial amount of research, focused primarily on building schedules for processes which are assumed to operate in a deterministic manner. This work describes an approach to directly incorporate schedules into a simulator for the purposes of schedule validation and testing of rescheduling methodologies when stochastic events occur. Although other types of uncertainty could be considered within the framework, the deviations presented in this work are those which can be represented as processing time variations and equipment breakdowns. The framework, when used open-loop, is an effective tool for evaluating the expected performance and robustness of various scheduling strategies. Two scheduling tools are compared, one which uses the uniform time discretized model and the other uses a non uniform discretization of time. In addition, user written logic has been incorporated into the simulator which allows the performance of various rescheduling techniques to be compared and evaluated prior to implementation in a processing facility. Numerical results of Monte Carlo simulation studies for both uses of the framework are presented.