desired output from the process is back projected through the process to determine production quantities of each task of the process within the production ranges these values are used to constrain a mixed integer programming evaluation of the schedule which may be used to control operation of the equipment application_number US 201213561891 A description referring now to fig1 a chemical production system 10 may provide for a variety of raw material sources 12 that provide material streams 14 for example through pipelines or other conveyor systems to batch processing units 16 which receive and process those materials to provide outputs to other batch processing units 16 or to an output stream 18 each of the batch processing units 16 and the material flows may be monitored and or controlled by electronic computer 20 having a processor 22 communicating with a memory 24 executing a stored program 26 the memory 24 may also include data 30 providing a model of the chemical production system 10 and various operating parameters including the amount of raw materials provided by the raw material sources 12 the processing capabilities of each of the batch processing units 16 the topology of their interconnection and the desired amount of different materials in the output stream 18 generally the model of data 30 may be used to determine an optimum control setting point for the material flows and the batch processing units 16 the batch processing unit 16 for example may be reactors distillers mixers filters coolers and other well known equipment used in the chemical processing area referring now to fig2 a given chemical production system 10 may be.