Wang C.,Swerea MEFOS |
Wang C.,Åbo Akademi University |
Zetterholm J.,Lulea University of Technology |
Lundqvist M.,Swerea MEFOS |
Schlimbach J.,DK Recycling und Roheisen GmbH
Energy Procedia | Year: 2017
The paper presents some research work on applying the oxygen enrichment technique to hot stoves that was carried out in one European RFCS project. In the presented work, both theoretical and practical work was studied. A dynamic model was used to investigate the effects of oxygen enrichment on hot stoves' performance under the condition that only blast furnace gas was used as the fuel gas. The modelling results showed that SOE will enhance the combustion process in hot stoves by increasing hot blast temperature and shortening the on-gas time, which were further verified by industrial trials performed at an iron-making plant. In addition, CFD modelling was performed by simulating different oxygen levels and lance positions at the burner to avoid the hot spot formation during the combustion. © 2017 The Authors.
Porzio G.F.,Sant'Anna School of Advanced Studies |
Colla V.,Sant'Anna School of Advanced Studies |
Fornai B.,Sant'Anna School of Advanced Studies |
Vannucci M.,Sant'Anna School of Advanced Studies |
And 2 more authors.
Applied Energy | Year: 2016
The use of Zinc-coated steel (e.g. galvanized steel) in melting cycles based on Electric Arc Furnaces can increase the production of harmful dust and hazardous air emissions. This article describes a novel process to simultaneously preheat and remove the coating from the scrap surface before the melting phase. The zinc in coating is removed in the gas phase by chloride containing syngas combustion and collected in a dedicated recovery system. Two possible innovative process routes are described, which involve plastic waste pre-treatment, shredded plastic gasification/pyrolysis, steel scrap preheating and zinc recovery processes. The routes have been modeled in an integrated flowsheet, in order to allow a comprehensive simulation and optimization of the pretreatment processes. The process optimization results in possible energy savings of over 300 MJ/t of preheated scrap charged in the Electric Arc Furnace for steel production. Moreover, a comparison among different scenarios according to economic and environmental criteria has been carried out. © 2015 Elsevier Ltd.
Lindvall M.,Swerea MEFOS |
Gran J.,Swerea MEFOS |
Sichen D.,KTH Royal Institute of Technology
Calphad: Computer Coupling of Phase Diagrams and Thermochemistry | Year: 2014
Vanadium (V) solubility in the Al2O3-CaO (25 mass%)-SiO2 system was determined experimentally at 1873 K and at a fixed oxygen potential of 9.37×10-11 bar. EPMA microanalyses were employed to identify the phases and their compositions in the quenched samples. It showed that the solubility of V-oxide increased slightly with decreasing Al2O3-content in the interval from 3 mass% to 53 mass%. The maximum V-solubility was up to 7 mass% (as V). A solid solution rich in V-oxide was detected. The Al2O3 solubility in this solid solution was found to increase with increasing Al2O 3-content in the liquid. © 2014 Elsevier Ltd.
Zetterholm J.,Lulea University of Technology |
Ji X.,Lulea University of Technology |
Sundelin B.,SSAB |
Martin P.M.,Siemens AG |
Wang C.,Swerea MEFOS
Applied Energy | Year: 2016
A large amount of energy is required in the production of steel where the preheating of blast in the hot blast stoves for iron-making is one of the most energy-intensive processes. To improve the energy efficiency of the steelmaking it is necessary to investigate how to improve the hot blast stove operation.In this work a mathematic model for evaluating the performance of the hot blast stove was developed using a finite difference approximation for the heat transfer inside the stove during operation. The developed model was calibrated and validated by using the process data from hot blast stove V26 at SSABs plant in Oxelösund, Sweden. The investigation shows a good agreement between the measured and modelled data.As a case study, the developed model was used to simulate the effect of a new concept of OxyFuel technique to hot blast stoves. The investigation shows that, by using this OxyFuel technique, it is possible to maintain the blast temperature while removing the usage of coke oven gas (COG). The saved COG can be used to replace some fossil fuel, such as oil and LPG.Furthermore, the effect of the cycle time on the single stove was studied. As expected, both the hot blast and flue gas temperatures are increased when increasing the cycle time. This shows that it is a good strategy for the hot blast stove to increase the blast temperature if the stove is currently not operated with the maximum allowed flue-gas temperature. © 2016 Elsevier Ltd.
Elfgren E.,Lulea University of Technology |
Grip C.-E.,Lulea University of Technology |
Wang C.,Swerea MEFOS |
Chemical Engineering Transactions | Year: 2010
The energy system of Luleå consists of the steel plant, a local CHP using process gases from the plant and the district heating system. Process integration work to improve the efficiency of the system is presently carried out by mathematical programming using a MILP tool (reMIND). Further improvements would need an improved possibility of the tool to consider the thermodynamic quality of the energy flows. This project aims to include exergy parameters in the node equations and object functions. This has been carried out for a test case, including a part of the system. Programming principles and some results are described. Copyright © 2010 AIDIC Servizi S.r.l.
Larsson M.,Swerea MEFOS |
Larsson M.,Lulea University of Technology
2015 World Congress on Sustainable Technologies, WCST 2015 | Year: 2015
Process Integration is a common name for system oriented methods and integrated approaches to complex industrial process plant design. In Process Integration, interactions in the industrial system are taken into account during process design and optimization via their material and energy flows. The use of systematic methodologies is a very effective approach to improve the energy and material efficiency of large and complex industrial facilities. In this paper an analysis of an integrated steel plant together with a new methodology to represent the resource efficiency is presented. The paper shows the importance of process integration as a methodology for the industry in their continued strive to strengthen its long-term sustainability. © 2015 Infonomics Society.
Millman M.S.,Tata Research Development And Design Center |
Overbosch A.,Tata Research Development And Design Center |
Kapilashrami A.,Tata Research Development And Design Center |
Malmberg D.,Swerea MEFOS |
Ironmaking and Steelmaking | Year: 2011
A unique in blow sampling system has been applied to a blowing converter to retrieve simultaneously representative bulk metal bath and slag/metal emulsion samples from seven specified positions and every 2 min from start of blow. Full sample datasets from 20 heats have been grouped according to differences in the bulk bath phosphorus removal profiles and analysed with respect to relative refining ability of the slag/metal emulsion and the bulk metal bath. The complexity of the thermokinetic relationships behind the removal of carbon and the transfer of silicon, phosphorus, manganese and sulphur between the metal and slag is highlighted and the metal circulation rate in the emulsion is derived. © 2011 Institute of Materials, Minerals and Mining.
Orre J.,Swerea Mefos |
Wang C.,Swerea Mefos |
Larsson J.,SSAB |
Chemical Engineering Transactions | Year: 2013
Pulverized coal is often injected into the blast furnaces (BFs) at the integrated steelworks as reducing agent for the hot metal production. The BF process will behave different depending on the injection coal used. The objective of this study is to investigate how different types of coal will influence the BF, and the total energy system atan integrated steel plant. The major process units covered in the model are coking plant, BF, reheating furnace at the rolling mill and a power plant. They are all linked to each other via the main products as well as process gases (i.e. blast furnace gas (BFG)and coke oven gas (COG)) and oxygen network. At the studied plant, the mixed gas of BFGand COG is used within the coking batteries at the coking plant and hot stoves at the BF. The fuel used at the reheating furnace is COG and oil with high heating values. In total, 13 different types of coal and one biomass charcoal are included in the study. Possible impacts on energy and CO 2 emission from a holistic view have been analyzed for different types of coal and injection rates. The different strategies on pulverized coal injection to BF are presented and discussed. Copyright © 2013, AIDIC Servizi S.r.l.
Karlberg M.,Swerea MEFOS
ISIJ International | Year: 2011
It has always been of greatest importance to control the temperature distribution in the products throughout the hot strip rolling process including the final coiling operation. A computational model of the latter has been developed and validated, which is presented in this paper. Furthermore, the influences of the different parameters on the transient thermal distribution are evaluated. The formulated model as accounts for twodimensional heat conduction is assuming axi-symmetric conditions. Temperature dependent properties are accounted for results in a nonlinear heat conduction problem that is solved by use of the Finite Element Method (FEM). The calculations have been validated by two full scale measurement campaigns and show a good agreement with measurements. © 2011 ISIJ.
Mousa E.,Swerea MEFOS |
Mousa E.,Central Metallurgical Research and Development Institute |
Wang C.,Swerea MEFOS |
Riesbeck J.,Swerea MEFOS |
Larsson M.,Swerea MEFOS
Renewable and Sustainable Energy Reviews | Year: 2016
The iron and steel industry accounts for about 20% of the annual industrial energy utilization. The intensive fossil fuel consumption in steel industry is associated with CO2 emission. In the absence of economically feasible and efficient methods for capture and storage of enormous quantities of CO2 emissions from steel industry, the use of biomass products as a source of energy and reducing agents provides a promising alternative solution for green steel production. However, the biomass application in iron and steel industry is still limited and it suffers strong competition from fossil fuels. The challenges of biomass usage in steel industry are included technical and economic aspects which required synergy between steelmaking and bioenergy sectors. Although intensive work has been carried out separately, there is a lack of link between these two vital sectors. The present article provides a comprehensive review of recent research progresses which have been conducted on biomass upgrading and analysing the opportunities and obstacles for biomass implementation in iron and steel industry. In the first part, an overview on the energy consumption and CO2 emissions in different iron and steelmaking routes is clarified. Moreover, the potential approaches of biomass conversion processes and upgrading technologies are reviewed. In the second part, an attention has been paid to the utilization of torrefied/pyrolyzed biomass in the energy-intensive ironmaking processes. Biomass addition to coal blend during cokemaking and its influence on the product coke quality is discussed. The partial and complete substitution of coke breeze with biochar in sintering process and its influence on the product sinter quality is explained. The impact of charcoal top charging or injection into blast furnace has been elaborated. Benefits and limitations of biomass application in each process are thoroughly discussed. In the third part, an economic analysis of biomass implementation for low-carbon steel is addressed. © 2016 Elsevier Ltd