A new type of non-ventilation excavation system model, which is based on the theory of simultaneously exploiting coal resources and gas from high-gas coal seams in a closed space, is established, consisting of a central ventilation tunnel and a non-ventilated excavating roadway. The respiration and comfort of the mining personnel, as well as gas control, are investigated. The nitrogen curtain is activated prior to opening the air door to replace the gas in the air perturbation space with nitrogen. The nitrogen curtain is simultaneously activated in the barotropic zone to prevent the flow of oxygen into the excavating roadway. The gas pressure relationship between different zones is studied when the air door is closed. The gas pressure only allows nitrogen to flow from the barotropic zone to the central tunnel zone, which ensures that the oxygen is effectively controlled under the closed air door condition. The proposed mechanism for blocking oxygen in the bypass tunnel is validated via the building analogy simulation and numerical simulation model. The presented non-ventilation excavation design efficiently blocks oxygen via simultaneous control of the air door and nitrogen curtain. This study provides a theoretical foundation for the application of non-ventilation excavation processing. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.