Problem Overview

A significant amount of waste heat is generated during various steel manufacturing processes, much of which remains underutilized due to limited technological scope, lower efficiency of existing technologies, challenges of integrating solutions with existing infra and higher cost for recovery. Harnessing this waste heat to produce other useful forms of energy is a critical challenge in energy management. Developing advanced technologies that enable high-efficiency waste heat-to-energy is an important and aspirational target in the field of energy innovation.

Scope and Definition

Steel industry produces various forms of waste heat which can be categorized into low (T<250^oC), Medium (T: 250-650^oC), and High (T>650^oC). This waste is produced from various sources which includes:

• Process units: Smelting, Refining, Casting and Rolling mills.
• Mediums: Flue gases, water sources, radiation heat and hot surfaces.
• Utilities: Power plants, boilers, and auxiliary systems (INBA system, steam networks, etc.)

Desired Solutions

The proposed solutions should be concentrated on these following areas:

1. Heat Recovery: Capturing waste heat from various sources through technology solutions. Desired solutions should be targeting convective medium as well as radiative heat sources as well. As per the steelmaking process, high grade heat which is primarily of radiation nature is critical and challenging. Proposed solution methodology should be encompassing those challenges in capture, conversion of waste heat in electricity or as heat is desirable. Primary solutions in radiative domain should either be: (a) innovative and scalable engineering solutions of existing radiative technologies available, or (b) new technology solutions and framework to capture this variety of radiation heat from sources.
2. Heat Reuse: Utilization of recovered heat for industrial heating applications.
3. Energy Conversion: Converting waste heat into other energy forms (such as electricity, or either for heating or cooling, etc.)
4. Heat Storage: Developing advanced material and technology solutions for efficient heat storage.
5. Heat Pinch Network Design: Development of digital solutions for heat pinch network design for maximizing heat into usable forms of energy through dynamic models. Heat sources in the steel plant are of various forms and is distributed across the network. In preview of harnessing these waste heat, a integrated network need to be designed and proposed which can utilize this waste heat into useful form of energy by integrating various technology framework with maximization of heat at minimum technology cost.

 
Other remarks on desired solution:

• The proposed technology should achieve high energy efficiency for waste heat to power conversion, surpassing the conventional technological barriers (w.r.t given grade of heat it can capture and the scale of technology)
• Innovative approaches such as hybrid systems or emerging technologies, that enhance overall system efficiency are of particular interest.