FlexHybHeat: Process development for a hybrid heating concept for highly flexible and low-CO2 billet heating in electric steel mills
Federal Ministry for Economic Affairs and Climate Action (BMWK) , 1 July 2024 to 30 June 2027
Project description
The overall objective of the FlexHybHeat project is to develop a flexible heating concept for steel billet reheating. Despite individual sequence requirements of the rolling mill, the heating concept should be able to achieve hot and direct input rates of 10% and 70% while at the same time allowing individually selectable reheating temperatures per billet. The reduction in primary energy requirements due to increased direct use is accompanied by a reduction in CO2, which is to be further reduced by the use of renewable energies in the form of electricity or hydrogen, for example. An increase in direct input while maintaining flexibility is only possible through a novel multi-stage heating concept. To predict the billet temperature, thermal models of the subplants will be combined into a process chain model and translated into a process control system that will control the entire plant. A life cycle assessment, which is also to be developed, will be integrated into the process chain model and the process control system so that the influence of, for example, energy source changes, load shifts or direct use rates on the efficiency, the CO2 footprint and the costs can be continuously represented both during the design of a heating system and during its operation. In this way, this project makes a contribution to decarbonization in the steel processing sector on the one hand, and also to the acceptance of computer-aided process operations in industry on the other. The solution developed should be suitable not only for new furnace systems but also, if possible, for retrofit installations, thus enabling market diffusion in the short term.
Hot cast steel billets on the way to reheating
The task areas of the project partners lead to the division of the joint research project into three subprojects:
- Modification of the industrial process control system and investigation of the influences on the operation as well as validation tests (ESF)
- Design, development and implementation of the process control system for the multi-stage heating concept (GIWEP)
- Development of plant models and an online life cycle assessment for integration into a process chain model (IOB)
Within the scope of the project, thermal process models of potential heating plants will be built. The plant models of the ESF plants (reciprocating hearth furnace, inductor, etc.) are validated by measurement campaigns. The individual plant models will be coupled in a process chain model in order to be able to represent multi-stage heating processes.
In parallel, the current furnace control system will be analyzed and a process control system will be developed that can handle multi-stage heating processes. A life cycle assessment will also be developed and integrated into the process control system. The process chain model offers the possibility to test different heating scenarios against each other in order to develop the optimal concept for ESF.
Validation tests of process chains, which can be reproduced by individual tests on the existing plants, serve to validate the process chain simulation as well as the process control system.
ESF provides the data basis and the know-how for billet heating, which are necessary for the development of a flexible heating concept. In the further course of the project, the validation measurements for the plant models, the retrofitting of the process control system and the validation tests for a design of the flexible heating concept will be carried out at ESF’s Riesa plant.
GIWEP will take over the analysis of the current furnace control at ESF and will develop a new process control system based on it. The process control system will map the multi-stage heating process on the basis of the process chain model and integrate the life cycle assessment. During the course of the project, GIWEP will conduct drag tests on the existing plants to validate the models.
The IOB starts with the development of plant models for heating plants, which will be linked to a process chain model in the course of the project, so that heating scenarios can be evaluated. In parallel, a life cycle assessment is being developed, which together with the process chain model will then be transferred to the GIWEP process control system.
Validation measurements are carried out jointly by all partners at ESF. For this purpose, the IOB will carry out exhaust gas measurements and temperature measurements of the furnace structure.
Project goals
The overall project objective is already given by the project title “Process development for a hybrid heating concept for highly flexible and low-CO2 billet heating in electric steel mills”. The following sub-goals are to be achieved:
- Process models to describe the heating characteristics and the energy conversion of individual systems
- Digital overall model for optimal operation
- Maximization of direct use to reduce primary energy demand and CO2 emissions
- Basic development of a level 2 process control system for a new type of heating process
Project participants
Contact
Funding
This project is funded by the Federal Ministry of Economics and Climate Action (BMWK) under the funding code 03EN2112A.
Funding is provided within the framework of the 8th Energy Research Programme of the Federal Government.