Ing. Büro Ipmatec Industriesysteme UG (Tornesch, Germany):

Grapengiesser C., Mag. Eng., e-mail: cg@ipmatec.de

Heat losses through chimney shafts in iron and steel industry are characterized with enormous saving potential that is practically using only partly at present time. Among the main obstacles for realization of the projects for usage of waste gases heat, possible delays of production processes and insuffi cient economical expedience can be mentioned. However, these conclusions don't relate to very efficient shiftable heating tunnels that are heated with waste gases; they provide ideal opportunity for cutting heat losses and harmful СО₂ emissions. The next advantages can be named for this method in comparison with other technical routes: high performance coeffi cient (energy saving is rather higher than amount of power regenerated from waste gas); power supply from waste air is synchronized with heat consumption (nozzle power and preliminary heating energy have linear dependence); possibility of integration in the existing technological process (operating and maintenance works can be conducted directly at production site); economical effi ciency (lowering of expenses and amortization period). Tunnel usage for heating provides productivity rise of the whole technological line in the case when a furnace is a “bottleneck”. Productivity rise and decrease of power expenses provide quick return of investments, in some cases during several weeks. It can be also expedient to equip additionally a tunnel with electric heating elements.