1679: Dynamic Simulation of Interconnected Solids Processes

Coordinator: Prof. Dr.-Ing. Stefan Heinrich

Conversion process in chemical and energy technology consist in most cases of multiple apparatuses, which are interconnected by streams of mass, energy and/or information. This interconnection influences significantly the operating behavior and especially the dynamics of the whole process. Therefore for design and optimization of such processes, especially with respect to saving of resources and energy, it is not sufficient to simulate the separate units independently, but the whole process should be simulated as an entity. For this purpose flowsheet simulation systems are used frequently in the design and optimization of fluid processes. In contrast, similar systems without restriction to certain applications only are not widely available for solids processes. Main reason for this lack of systems and dynamic models is the complicated and complex description of solids with their multivariate and distributed properties.

Therefore, it is the general aim of the Priority Program to develop numerical tools for the dynamic simulation of interconnected solids processes. To reach this aim dynamic models of the many different apparatuses and machines for solids processing have to be developed and to be implemented. Required are physically based predictive models, which allow a sufficiently accurate description of the process, have not too high requirements for computing resources and are widely applicable. With respect to the use within a flowsheet simulation framework, they should not be restricted to certain materials or classes of materials. Furthermore, they have to consistently treat the disperse properties of the solids. These distributed properties are not the particle size only, but may also be e.g. the density, composition, shape or porosity of the particles.

Beside the development of new process models also new and extended models for the description of solid materials and particles are needed. These models are required to deduce information about product quality or required product properties as for example the solubility or flowability of powders from the disperse properties calculated by the process models. Furthermore, the material models are required to determine concentrated parameters identified during the model reduction from easy to measure particle properties.

Simulation of solids processes under consideration of distributed properties leads commonly to systems of population balances, in which equations for the conservation of mass and energy are coupled with equations for the description of the population. For the solution of such systems exiting solvers for univariate systems shall be improved and be extended to the solution of multivariate population balance systems.

The research work of the Priority Program is divided into three areas:

A - New physically based dynamic models of processing units

B - Material models for solids processes

C - Algorithms and process simulation

Within the Priority Program scientists of different disciplines and from different universities will cooperate. The program is planned for a duration of six years and is financed by the German Research Foundation (DFG).