Quantitative study on steam system thermal inertia based on a dynamic hydraulic analytical model

Abstract

Integrated energy system (IES) in industrial parks is pivotal to China's carbon neutrality path, where steam plays a critical role as an energy carrier and raw materials in the production process. Utilization of the thermal inertia of steam systems may become a means to address challenges in industrial park IES dispatch. However, researchers have less discussed the dynamic modeling and inertia quantification of industrial steam systems compared to district heating. This work proposes a dynamic hydraulic analytical model (DHAM) of steam systems reflecting the spatial and temporal transportation of steam by introducing the reference temperature and momentum linearization assumptions. Further, a steam thermal inertia model (STIM) which comprises five storage key parameters and two indexes, is developed to quantify the thermal inertia based on DHAM. Validation results of DHAM in an industrial park demonstrate that the relative error is less than 3%, achieving high accuracy. Whilst the thermal inertia of a 163-node steam system in two operation conditions is quantified and compared. Results show that the net heat storage of the steam system could reach 7440.30 kg while the positive utilization rate in both scenarios never rises above 3%. It indicates that the thermal inertia as virtual storage can fully cover the dispatching demand while is not utilized and lacks the regulation strategy of active charging in operation. DHAM and STIM proposed in this study lay the quantitative basis for steam system analysis and operation optimization of industrial park IES.