Modelling an Ice cream factory for debottlenecking

摘要

The process plant of Unilevers ice-cream factory in Hellendoorn, TheNetherlands, needed to increase their output by 30%. Outsourcing the volume orworking overtime are not possible to generate the additional output. Theimmediate engineering response was to propose a capital investment project forbuilding additional capacity. The key question is then in which area of the plantto invest, because the bottleneck might not be obvious and depend on the actualportfolio. In this paper we will pursue a modelling and simulation route toidentify which bottleneck(s) need enlarging, taking into account the costs andthe time needed. The model will be designed to quantify the effect of workingprocedures, minimum storage time of the mixes, equipment extensions andmodifications.The effects will be quantified by the feasibility of the production schedule forthe whole factory.Using the model, various scenario's have been simulated and the outcomeevaluated. A number of bottlenecks have been identified, the two main onesbeing the high non-operational time of the main heat exchanger and the fact thatonly the packing lines are scheduled.By scheduling the factory as a whole, the available overall capacity of thefactory can be increased significantly. The above factory schedule generates 10-30% additional capacity without significant capital expenditure.