Optimization of design and operation of a digestate treatment cascade for demand side management implementation

• Published in: Computers & chemical engineering 2024-12, Vol.191, p.108838, Article 108838
• Main Authors: Röder, Lilli Sophia, Gröngröft, Arne, Grünewald, Marcus, Riese, Julia
• Format: Article
• Language: English
• Subjects: Biorefineries; Design optimization; Dynamic scheduling; Flexibility; Techno-economic assessment
• ISSN: 0098-1354
• DOI: 10.1016/j.compchemeng.2024.108838

•Extension of a previously developed decision support tool that helps to quickly understand the economics of implementing demand-side management (DSM). The equation extensions describe the size of the intermediate storage tanks depending on the oversizing of the upstream and downstream unit operations.•Dynamic simulation of a downstream digestate separation cascade in biomethane production, considering start-up and ramp-down times of the individual unit operations and the dependence of the separation efficiency on the flow rate.•Dynamic scheduling optimization of the digestate separation cascade with help of the extended decision support tool and the dynamic simulation, responding to changes in electricity prices as part of the DSM implementation.•Analytical comparison of the presented dynamic DSM evaluation approach with the steady-state method of previous studies. Sustainable chemical engineering through demand side management (DSM) and renewable feedstock integration e.g. in biorefineries are key to optimizing the use of fluctuating energy resources and minimizing environmental impact while conserving resources. This contribution presents the results of the economic evaluation of integrating DSM into biofuel biorefineries through a dynamic simulation approach. A previously developed decision support tool for DSM implementation was extended to describe the size of intermediate buffer tanks as a function of oversizing up- and downstream processes. Design optimization of the process cascade determined the oversizing that allows the optimal balance of operational cost reduction through flexibility and capital cost increase through oversizing. Scheduling optimization validated the results of the steady-state optimization and show that, by considering interactions between processes, buffer tank capacity can be reduced, while increasing DSM potential. [Display omitted]