Application of Excess Heat Recovery in the Steel Industry
Introduction
The steel industry is one of the world’s most important economic sectors, since it supplies most of the component materials used for construction, infrastructure, and vehicle production. Globally, it is estimated that the industry produces around 1.5 billion tonnes per year, with the majority of the products used in the construction industry. As the steel industry is so energy-intensive, its operations produce copious amounts of heat, around 30% of which is wasted due to poor efficiency in the cooling down of steam and other gaseous by-products. This waste heat can be used to generate electricity in the form of combined heat and power (CHP) systems and can even be recovered from the production process itself. This paper will examine the use of excess heat recovery in the steel industry and focus on the energy efficiency improvements that this technology can bring.
Excess Heat Recovery
Excess heat recovery (EHR) is a process whereby excess heat is captured as steam, or other forms of energy, during the steel-making process and then used to generate electricity or drive other industrial processes. This is done by capturing the waste heat in a heat exchange unit, such as a heat exchanger, and then using it to generate steam or generate electricity in a CHP system. This is an efficient and cost-effective way of making use of the energy that already exists in the process, as any energy created or used by the process can be reused or sold.
The amount of heat recovered from the process depends largely on the form in which it is produced; for example, furnaces which produce hot gases will produce more heat for EHR than furnaces which produce mainly solid waste. Additionally, using EHR in combination with other energy-saving measures can decrease the overall energy consumption of the production process.
Benefits of Excess Heat Recovery
The benefits of using EHR in the steel industry are numerous. Firstly, it increases the energy efficiency of the production process, reducing the amount of energy that is wasted due to poor efficiency in the cooling down of steam and other by-products. By recovering this wasted energy and converting it into usable forms of energy, the company can benefit from reduced fuel consumption, lower electricity costs, and improved productivity.
Secondly, excess heat recovery can help to reduce the environmental impact of the steel-making process. By recovering heat which would otherwise be lost through the cooling process, EHR can significantly reduce the industry’s carbon footprint. This is beneficial to both the environment and the economy, as it helps to reduce the amount of unrecoverable by-products produced during the manufacture of steel.
Finally, EHR can be used to increase the process’s overall efficiency by providing additional sources of process energy. The captured heat can be used to power various types of equipment within the steel-making process, from compressors and pumps to autoclaves and heat treatment furnaces. This can help to reduce the process’s costs and maximise energy productivity.
Conclusion
Excess heat recovery is an effective and cost-efficient way of utilizing excess heat from the production process to generate electricity or drive other industrial processes. This approach can significantly increase the overall energy efficiency of the steel industry, reducing energy wastage and the production of carbon emissions. Additionally, it can be used to drive various types of equipment within the steel-making process, which can help to reduce the process’s costs and maximise energy productivity. Overall, EHR is an important tool that should be used to improve the sustainability and efficiency of the steel industry.
