Worldwide, the demand for raw materials and materials is constantly increasing, being proportional to the growth of the population. In this sense, the demand and production of solid fuels such as coal has grown steadily. At the level of the European Union, due to the restrictive coal extraction policy, production has steadily decreased and coal-producing countries have had to implement closure programs with strict deadlines. As mining networks shrink, there is an intensification of risk factors due to changes in the ventilation system. The paper presents the restructuring of a complex ventilation network.

In order to ensure the microclimate conditions for the exploitation of useful mineral substances underground, it is necessary to ensure the control of gas emissions from the field and from the exploited space. For this it is necessary to ensure a balanced air flow at the level of each active mining work in order to dilute the gases. Specialized programs are used to ensure the optimal distribution of air flows at the level of each mining work. The paper presents the modelling and solving of the ventilation network related to Livezeni Mine with the help of the 3D CANVENT program.

The ventilation networks are associated with the set of underground mining works used for the extraction of useful mineral substances. Over time, the ventilation networks involve a change in the structure due to either the expansion or restriction of the mining works structure. For the establishment of air flows at the level of each active mining work, specialized programs are used at international level. These programs allow the modelling and solving of complex ventilation networks. The most advanced specialized programs are those from the VENTSIM range. The paper presents the updating of the ventilation network related to Livezeni mine, with the help of the VENTSIM program.