What is a virtual plant?
A virtual plant or digital twin is a fully functional digital clone of a real-world process. For the FlashPhos process, a model was built based on the mass and energy balance supplemented with thermodynamic data which can predict how the real-world process will react.
Data input for virtual plant
How can it be used in the FlashPhos process?
The digital twin can be used in different ways throughout the FlashPhos development process. For example, it can be employed in the engineering phase to calculate the flow rates of different reagents, the energy requirements of furnaces and heat exchangers, and their expected variations. In this way, the virtual plant supports the dimensioning of pipes and units.
The model will also be used to compare different sewage sludge compositions and their influence on the amount and quality of phosphorus, refiner slag, and other streams which are produced. Different scenarios can further be provided as input for life cycle assessments (LCAs). This is highly important for the commercialization of the technology, as it allows us to make a valid selection of potential raw materials.
How is it built?
The core of the virtual plant is a flowsheet model (mass and energy balance) built using the METSIM® software. The behaviour of the different elements is calculated based on experimental results, and when those are not available, by assuming chemical equilibrium in the different unit operations.
METSIM Software
This core model has already been installed on a server and can be controlled using a ProOpt web interface where the input is added and the output is presented. This interface is accessible to all FlashPhos partners and will assure that everyone is calculating with the same assumptions. Therefore results of different simulations can be easily compared.
When the FlashPhos pilot plant has been built and pilot data are available, these results will be integrated into the model to improve its predictability. Thus, the virtual plant can be described as a learning model providing a common framework for capturing the gained knowledge.
Scheme of virtual plant learning