An analysis of waste heat in steel plants shows many potential power sources. In addition to heat lost in exhaust gas streams, a significant amount of heat is wasted in cooling water. Until recently waste heat recovery systems have required major investments and substantial design changes to production processes. Thanks to new technology, however, it is now possible to simply and efficiently convert even low-temperature heat into power with only minor modifications to existing infrastructure.
Recovering low temperature heat
Traditionally, waste heat recovery solutions require temperatures between 150 °C and 600 °C with technologies such as steam turbines and high temperature ORC (organic rankine cycle) systems to generate electrical power. However, recent developments have led to the commercialization of conversion technologies that can operate at lower temperatures, down to 70 °C.
In reheating furnaces, 10-17 % of the primary energy input is lost to cooling water circulated through the skid pipes. What if that heat could be recovered and turned into electricity while also reducing its cooling load?
Because of new technologies that make it possible for heat to power systems to operate on hot water under 100 C, a 150 ton/h reheating furnace could actually produce up to 1.1 MW of electricity and reduce its cooling requirement by 10%.
How to get heat power
Climeon’s innovative technology takes the thermal energy in hot water between 70 and 120°C and converts it into electricity. The adaptive control system has the ability to automatically synchronize the system to match available heat, ensuring high efficiency even under fluctuating operation. The Climeon Heat Power system is fully automated and requires minimal human intervention.
By extracting heat from the skid cooling circuit in the reheating furnace, approximately 10% of the wasted heat can be converted into useful electricity. The rest is rejected to the existing cooling system, reducing the cooling requirement of the reheating furnace by 10%. For reheating furnace owners, the Climeon Heat Power system represents the simplest opportunity to lower both emissions and costs.
