Abstract: An enclosed storage tank for simultaneous addition and removal, and storage, of two liquid layers of different density comprising a tank shell having a bottom, side wall and a roof and a column extending from the shell bottom to at least near the roof; a horizontal first liquid distributor spaced around and extending outwardly of the column and located in the upper part of the tank and having an upwardly facing liquid distribution surface; a low density liquid conduit extending from outside the shell into communication with the column whereby low density liquid can be fed to the column and then flow to the first liquid distributor and onto the upper liquid distribution surface; a horizontal second liquid distributor spaced around and extending outwardly of the column above which the column extends and spaced above the shell bottom; the second liquid distributor having a downwardly facing liquid distribution surface; a high density liquid conduit extending from outside the shell into communication with the col

Abstract: A liquefied gas storage tank having insulated vertical walls and an insulated top, said tank being located in and surrounded by a body of water with the exterior water level below the top of the tank walls, the tank interior space containing a layer of water in communication with the body of water so that water can be supplied to and be removed from the tank, an insulating layer floating on the water layer in the tank, and a liquefied gas floating on the insulating layer.The insulating layer can include a float which extends over the water layer except for a rim space between the periphery of the float and the tank walls, and an insulating liquid in the rim space which has a specific gravity less than water and higher than the liquefied gas, and with the insulating liquid being essentially immiscible with water and remaining liquid at the liquefied gas storage temperature.

Abstract: In a vertical cylindrical liquid storage tank having a circular floating roof, an improved sealing means including an elastomeric composite strip impermeable to vapor connected at its inner edge by an essentially vapor tight joint to the roof edge and extending as an annulus outwardly to the tank inner side wall, the elastomeric composite strip comprising a plurality of flexible resilient elongated stiffeners laterally positioned and embedded in elastomeric material, and the elongated stiffeners extending from the strip edge joined to the roof and terminating short of the strip edge at the tank wall.An elastomeric composite strip, impermeable to petroleum vapor, having a plurality of flexible resilient elongated stiffeners laterally positioned and embedded in elastomeric material, with the elongated stiffeners extending from one strip edge and terminating about at the other strip edge.