4 PROCE SS ANALYSIS The first question is one of simple process analysis. The question is based on an Iron Ore refining operation in Trinidad as described in my teaching case Terwiesch and Loch 2002. QUESTION 1 The Circored process produces direct reduced iron in Latin America. The production process starts with a pile of iron ore fines. The ore is moved through seven process steps before it emerges as finished direct -reduced -iron briquettes. The steps and their capacities are as follows: • Pre- Heater: 60 tons per hour • Lock Hoppers: 55 tons per hour • First reactor: this reactor holds up to 14 tons of iron and iron needs to spend 15 minutes in the reactor • Second reactor: this reactor holds up to 200 tons of iron and iron needs to spend 4 hours in the reactor • Flash hea ter: 62.5 tons per hour • Discharge: 59 tons per hour • Briquetting: three machines of 27.5 tons per hour each Where in the process is the bottleneck and what is the overall process capacity? Justify your answer. The key academic concept that is tested in this question is the concept of a bottleneck. The bo ttle neck of a process is the process step with the lowest capacity. For most of the steps, the capacity is give n in t he question. In the case of briquetting, one needs to realize that there are three machines (and thus three times the capacity of one machine). Moreover, the capacity calc ulations fo r the two reactors are not trivial as one needs to derive the capacity by dividing the size of the reactor (e.g., 200 tons) by the reaction time (4 hours). Finally, we should not forget that this question requires a fair bit o f natural language processing to absorb the input and to create the output. So , let’s see what happened when I entered this verbatim int o t he Chat GPT prompt.