Continuous Flow Type Gas Blending Facility Used for Autonomous and System Diving

The present paper, deals with a new gas blending method, in order to achieve a continuous flow mixing, and describes the associated facility for manufacturing of breathable mixtures used in the professional diving field. The facility is an original equipment conceived by the authors, specially designed to achieve the blending of two or three gases in order to form binary or ternary breathable gas mixtures used for activities which assume hyperbaric processes. The working principle of the equipment is based exclusively on gas dynamics phenomena which ensure the injection of the pure gases at a constant mass flow rate, independent of the pressure value at the consumer. As a particularity, the system facilitates the blending of any type of gases irrespective of the ratios of the compounds that forms the mixture. In order to understand both the proposed blending method and the manner in which the facility operates, as a first subject the paper describes the technological scheme of the blending facility. Starting this point on the gas mixture preparation procedure is described together with the associated computing relationships. The last subject is related to the designing process of the main parts of the facility. At the end of the paper, some general conclusions regarding the facility conceived for gas mixture manufacturing are presented, and how it relates to facilities from the same category. (C) 2017 Published by Elsevier Ltd.