Cost Effective Technician Training Simulator for New Acetylene Hydrogenation Reactor
Qenos installed an isothermal acetylene hydrogenation reactor (“Converter”) as part of a feed conversion project on an ethylene cracker. A dynamic simulator was used to assist in the commissioning and operation of the new Converter. For cost reasons, the simulator was built in-house rather than purchased from a vendor. The Converter unit consists of a feed /effluent exchanger, a feed preheater, the multi-tube fixed catalyst reactor in a methanol bath, and a methanol condenser. The calculation engine was built in an Excel spreadsheet. The reactor and condenser were each modelled as zoned equipment. The characteristics of the catalyst were modelled using a first principles approach from textbooks, and validated against vendor performance data. Similarly, characteristics of the methanol bath and condenser were modelled using classical heat transfer correlations and validated against the equipment specification sheets. Spreadsheeting techniques developed by the author over many years were integral to the final dynamic model. The Simulator was run on an off-line Operating console, using the graphic display designed for the real unit. The plant’s control system was programmed to exchange data with spreadsheet, rather than with field devices. The PID functionality of the control system was utilised for the Simulator just as it would be in the real plant. The simulator was highly successful both in allowing the technicians to learn about the new Converter, and in testing tuning strategies and parameters.