Storage facility for the storage of highly volatile hydrocarbons

Abstract

The invention relates to a storage facility for the storage of highly volatile hydrocarbons, comprising at least one vertical round tank (I) which is equipped with a floating cover ( 5 ), covering the liquid surface, in the form of a floating roof or a floating ceiling, wherein an annular space ( 8 ) formed between the cover ( 5 ) and tank wall ( 3 ) is sealed by means of flexible sealing elements ( 9 ) and wherein fittings ( 12, 13 ) for automatic control of overpressures and under pressures in the space ( 4 ) under the cover ( 5 ) are integrated into the cover ( 5 ). The fittings ( 12, 13 ) of the at least one round tank (I) are connected to a vapour line ( 14 ), the upper end of which is led out of the tank ( 1 ) and is in turn connected to a separate vapour expansion tank ( 15 ), wherein the round tank (I) and the vapour compensation tank ( 15 ) form a closed system.

What is claimed is: 
     
         1 . A storage facility for the storage of highly volatile hydrocarbons, comprising at least one vertical round container which is provided with a floating cover for covering a liquid surface in the form of a floating roof or a floating cover, wherein an annular space formed between the cover and the container wall is sealed by means of flexible sealing elements and wherein fittings are integrated in the cover for the autonomous control of overpressure and negative pressure in a space underneath the cover, the improvement wherein the fittings of the at least one round container are connected to a vapor line which is led out of the container at an upper end and, in turn, is connected to a separate vapor equalization container with the round container and the vapor equalization container forming a closed system. 
     
     
         2 . A storage facility as in  claim 1 , wherein the vapor line has a vertically extending section inside the round container, which is formed as a bellows and which expands or contracts depending on a floating height of a floating cover. 
     
     
         3 . A storage facility as in  claim 2 , wherein the bellows surrounds a fixed support and wherein the bellows is attached at an upper end of the support. 
     
     
         4 . A storage facility as in  claim 3 , wherein the support is formed as at least one of a sampling, sounding, measuring and guide tube and as a roof support. 
     
     
         5 . A storage facility as in  claim 1 , wherein the vapor line is guided within the round container along a rolling ladder. 
     
     
         6 . A storage facility as in  claim 1 , wherein the vapor equalization container contains a flexible diaphragm with a ballast weight acting thereon. 
     
     
         7 . A storage facility as in  claim 1 , further comprising at least one of vapor recovery and vapor combustion devices connected to the vapor equalization container ( 15 ). 
     
     
         8 . A storage facility as in  claim 1 , comprising a plurality of storage containers, all connected to a common vapor equalization container. 
     
     
         9 . A storage facility as in  claim 6 , wherein the vapor equalization container is formed with its ballast weight, taking into account flow resistances of the vapor line such that it avoids a negative pressure in a space below the cover by supplying vapors to said space in the required quantity and time, and is operative to prevent a predetermined overpressure in said space below said cover by absorbing vapors in the required quantity and time from the space. 
     
     
         10 . Storage facility as in  claim 1 , further comprising a blower, arranged in the vapor line, which supports the removal of vapors to the vapor equalization container, and is controlled by pressure sensors in the container below the floating cover. 
     
     
         11 . A storage facility as in  claim 1 , comprising a plurality of storage containers which are divided into at least two groups according to their pressure exerted on the liquid therein via the floating cover, wherein a vapor equalization container is assigned to each group adapted to this pressure and wherein the different vapor equalization containers are connected via a vapor equalization line, into which a pressure increasing blower is inserted for conveying vapors from a low-pressure vapor equalization container to a higher pressure vapor equalization container. 
     
     
         12 . A storage facility as in  claim 1 , wherein a space remaining between the floating cover and the container bottom in the lowest position of the floating cover of the round container is connected to a purging liquid container, and wherein the hydrocarbon vapors present in said remaining space after the container has been emptied are removed to the vapor equalization container by introducing a purging liquid into said remaining space. 
     
     
         13 . A storage facility as in  claim 12 , wherein water or storage liquids with a low vapor pressure from other storage containers of the storage facility are used as purging liquid.