The processes of foundry of machine-building enterprises are accompanied by the release of excess heat and a large number of hazards. Reducing the harmful impact of enterprises on the environment should be ensured by a complex of technological and construction measures, as well as the effective operation of ventilation systems. When designing ventilation systems, it is necessary to solve an optimization problem that takes into account their energy and environmental reliability, and economic efficiency. As a result of the analysis of the reliability of ventilation systems, their energy efficiency, heat consumption for the needs of heating and ventilation of a number of metallurgical industries, in order to reduce operational energy costs, it is recommended to solve a set of problems that include increasing the level of use of secondary energy resources. The authors propose a cyclone-heat exchanger, where cleaning of dust and gas flow and its heat recovery are combined in one apparatus. Design and construction of energy-efficient ventilation systems with high technological reliability will reduce operating power consumption from 30 to 75%.