Abstract: A plate heat exchanger generally for media liberating a gaseous agent from a liquid heat-transfer medium during heat-exchanging process characterized in that stacks of heat-exchanging plates are placed inside a housing, the interior of this housing being in communication with channels for passing a gaseous heat-transfer medium, whereas each of the heat-exchanging plates has partitions providing a required flow direction for the gaseous agent liberated from the liquid heat-transfer medium and contributing to its discharging from the zones of its liberation disposed at different height of the channel.