Recovery of thermal waste from an industrial process
Energy is an increasingly indispensable and expensive resource and improvements in energy efficiency become increasingly fundamental and strategic for companies, which find potential savings in the recovery of heat from their industrial processes, and its conversion into electric energy.
Zuccato Energia ORC systems can be used precisely for this purpose: recover energy from most industrial processes involving heat and convert it into clean electricity. Among the sectors that can benefit greatly from this, we certainly find the metallurgical industry.
One of the studies we carried out to evaluate the application of one of our ORC modules concerns a rolling mill, which uses an industrial machine for hot or cold rolling and / or shaping of malleable materials in its production process. This company has a longitudinal member furnace, used for heating slabs, billets or bars before rolling. The object to be heated is passed through the oven where temperatures normally reach up to 1200 ° C.
The fumes produced by the normal activity of the furnace have an important thermal potential, which can be exploited through the ORC technology which transforms the recovered thermal power into electrical power that can be used to cover the self-consumption of the plant.
The recovery of hot fumes is in particular achieved through a heat exchanger that transfers the thermal power possessed by the fumes to clean water, the carrier fluid used for all Zuccato Energia ORC systems. Our choice to use water as a carrier fluid is dictated by the fact that it is a known fluid, easily available, which does not require special management and maintenance works, which does not present a high cost and above all which is safe for the environment.
The hot fumes are first of all made to flow into a fumes treatment system and only subsequently into the heat exchanger, to extract the thermal power contained in them and exploit it to make pressurized water at 160 ° C available to power the ORC module.
The ORC module selected for this installation is the ZE-500-LT module which can produce up to 561 kW of electricity, recovering a thermal power of 3 500 thermal kW, which translates into an electrical efficiency of 16%.
Thanks to the use of an ORC module inside the rolling mill, the thermal energy otherwise wasted as it is released into the environment can be used to produce electricity.
This reduces the heating that would affect globally, also reducing the use of electricity produced from fossil sources, enhancing the energy inside the plant and increasing the overall efficiency of the entire plant.