This paper focuses on the development of a rescheduling system to cope with unexpected process events in pipeless plants. Since the pipeless batch plant relies on mobile vessels for the transfer of material from one stage of processing to another, the process variations may be more often than any other batch processes. The process deviations from original schedule are mainly process time variations. This rescheduling system for the pipeless batch plant overcomes the processing time variations by adjusting the starting time of reactions and determining the sequence of equipment to be processed. So it treats the earliness of operations as well as tardiness of reactions efficiently. In this study, the rescheduling system is implemented and two main approaches for the solution of various cases are proposed.