Trends towards product differentiation, fast changing market conditions, and shorter product lifecycles demand flexible production solutions for the chemical industry. Modular production systems promise to provide the required capacities as needed in a short period of time. However, the potential of modular production systems can only be fully utilized if they are embedded in modular and thus flexible logistics processes. For this reason, standardized logistic modules need to be defined. Process standardization is the starting point for reducing the number of variants and minimizing the number modules. Thus, in this paper a reference process model is developed. The standardized processes defined in this model are then used to form modules by applying a method from cluster analysis.