Abstract: This invention is a system which purifies or removes air pollutants from the vent gas stream of a fixed roof liquid storage tank. It incorporates a novel method for insuring that tank venting will not be restricted or prevented by the air pollution control or purification devices, and thereby eliminates a potential cause of deformation or collapse of a fixed roof liquid storage tank upon which it may be installed. It is constructed of essentially two parts as follows:1. a purification unit, which may contain filtration and/or sorptive media, connected by a pipe or chamber to the vent connection of a fixed roof liquid storage tank2. a forced draft fan, selected according to specific design criteria, which forces air into the pipe or chamber which connects the purification unit and the fixed roof liquid storage tank.

Abstract: A deaerator device for separating non-condensable gases from condensate. The device includes an upper deaerator stage means comprising a spray nozzle assembly which directs liquid particles under high velocity into a hood located thereabove. In the hood, the particles are raised to their saturation temperature by steam introduced into the device wherein the non-condensable gases are liberated from the condensate and vented to the atmosphere. Located below the nozzles is tray for receiving the condensed water. The tray has a plurality of openings which directs condensate into a lower deaerator stage consisting of a packing which removes substantially all of the non-condensable gases left in the condensate.