Keywords: contract network, ecological production control, fuzzy-Petri net
Energy and material management based on a fuzzy-Petri net approach
In modern production systems, materials and different forms of energy are provided, converted, stored and transported. Environmental impacts can be identified at any stage of the energy and material flow process. Due to the fact that production units and processes are interconnected with energy and material flows, it is of special interest to implement production control policies, which control the energy and material streams. In this way, it is possible that available resources are utilised most efficiently and emissions and by-products caused by the production process are reduced. Achieving this goal in one step, the input and output streams of a production system have to be balanced. This can be done with input-output models (e.g. unit operation models) or with simulation systems. Due to the requirements of the modelling of real production systems (simultaneous modelling of structure and state of the production system, availability to describe analytical and synthetical production structures, possibility to model different aggregation levels), a Petri net approach seems to be adequate to this task. In a second approach, control strategies concerning economic and ecological goals have to be integrated. In accordance with the structure of the available expert knowledge (fuzzy knowledge), a fuzzy Petri net approach for an environmental integrated controlling of interconnected production systems is discussed. Validating this approach an exemplary production system from the textile industry, consisting of a dye house, a hydropower plant, a boiler house, and a flue gas neutralisation facility is analysed.