ISO 13579-2:2013

Overview - ISO 13579-2:2013 (Reheating Furnaces for Steel)

ISO 13579-2:2013 establishes a standardized methodology for measuring the energy balance and calculating the energy efficiency of reheating furnaces for steel. It applies to reheating furnaces as designed by furnace manufacturers and complements the general methodology in ISO 13579‑1. The standard defines required measurement methods, calculation procedures, and the structure of an energy balance and efficiency evaluation report. It is explicitly limited to the reheating furnace itself and does not cover downstream or upstream process equipment (for example, rolling-mill process efficiency).

Key technical topics and requirements

• Energy accounting framework: Definitions and symbols for total energy input, fuel equivalent energy, other energy inputs, total energy output, and thermal energy output.
• Thermal energy components: Clear categorization of thermal outputs such as effective energy (enthalpy gained by products), jig loss, sensible heat of exhaust gas, wall loss, cooling-water loss and blowout/opening losses.
• Measurement methods: Guidance on measuring fuel, atomization agents, combustion air and exhaust gas, controlled atmospheric gases, product and jig temperatures, furnace wall and inner-wall temperature, inner pressure, cooling water, and electrical auxiliary equipment.
• Calculation rules: Procedures for computing total energy input, total energy output, and total energy efficiency, including treatment of electrical generation loss, recycled energy, and utilities generation energy.
• Basic measurement conditions: Requirements for state of furnace, measurement duration, reference conditions (elevation effects noted), units, and fuel characterisation.
• Reporting and uncertainty: Required content for the energy balance evaluation report and informative annexes that provide a sample report and an uncertainty assessment methodology.

Practical applications and typical users

Who uses ISO 13579‑2:

• Furnace manufacturers (design validation and performance declarations)
• Plant energy managers and metallurgical process engineers (benchmarking and energy audits)
• Energy auditors and consultants (consistency in measurement and reporting)
• Procurement/specification authors (tender requirements and acceptance testing)
• Regulatory bodies and certification schemes requiring standardized efficiency metrics

Typical use cases:

• Verifying reheating furnace performance and identifying major loss sources (wall, exhaust, cooling water)
• Establishing baseline energy intensity and tracking improvements
• Preparing standardized efficiency reports for customers or regulators
• Comparing designs and technologies on an energy-basis across facilities

Related standards

• ISO 13579‑1:2013 - General methodology for measuring energy balance and calculating efficiency
• ISO 13574 - Vocabulary for industrial furnaces and associated processing equipment

Keywords: ISO 13579-2, reheating furnaces for steel, industrial furnaces, energy balance, efficiency calculation, measurement methods, thermal energy balance, fuel equivalent energy, energy audit.