Biogas can be fed to block-type thermal power stations (CHP) to produce heat and electricity required on-site the fermentation plant. Surplus electricity is exported to the national grid. This local usage of the biogas does not require expensive gas cleaning (see PSC 2016), but it has the disadvantage that the storage capacities for gas as well as for electricity are extremely limited. Hence, a control structure is required to handle surplus production of gas and limits in the intake capacity of the national grid.
In PSC2017, two possible disturbances to a steady state operation of the CHP’s are evaluated. Scenario 1 considers a slow but continuous increase in the fermenter’s gas production while in scenario 2 a sudden shutdown of one of the three CHP’s is simulated. The goal is to optimize the controller settings so that the amount of gas sent to the flares is minimized (scenario 1) and an opening of the safety valve is avoided or at least kept as short as possible (scenarios 1&2).
In the reference case, all controller parameters have been left in their default setting (PB = 100% / TI =1 min / TD = 0 min). This leads to an accumulated loss of gas of 36.2 kg via the flares. The safety valve does not open at any time.
Find controller parameters so that even less gas must be burnt in the flares, but don’t forget to keep a look at the safety valve!
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3 March 2017: Launch of the PSC2017 at the Symposium Teaching Process Simulation in Berlin
16 February 2018: Submission closing day for PSC2017.
23 February 2018: Award Ceremony of PSC2017 at the Symposium Teaching Process Simulation in Berlin