This paper presents a virtual plant modeller (VPMOD), which formally characterizes and integrates chemical product designs, batch-chemical equipment (plants), the real-time scheduling of chemical batches, and the control of chemical transport through the plant. These models provide a framework for agile batch-chemical manufacturing that has the ability to reroute and control chemical product flow automatically in a flexible plant subject to unexpected events, such as changes in demand patterns and equipment failure. A formal logic model is generated to control the actual system events, which are non-deterministic. A simulation environment in VPMOD is used to validate schedules and control logic based on plant models supplied by industry. The formal models have been implemented in an object-oriented language.