Containment system for storage systems having discontinuities

Abstract

A system for sealing a liner about an internal member in a structural envelope, such as a liquid storage tank. A mechanical seal is located between the liner's first edge and the structural envelope and forms secondary containment between the structural envelope and the liner. A plate sealably attaches outside the outer perimeter of the mechanical seal to either the inner or outer surface of the structural envelope and forms a continuous envelope extension from the liner to the discontinuity. The plate provides secondary containment between the continuous envelope extension and the structural envelope. Tertiary containment is achievable through use of a liner boot, the outer edge attached to the liner outside the perimeter of the mechanical seal and the inner edge mechanically sealed to the discontinuity.

The embodiments for which an exclusive property or privilege is claimed are defined as follows:  
     
         1 . A system for sealing a liner about a discontinuity at a structural envelope for containing fluid, the liner forming secondary containment between the liner and an inner surface of the structural envelope, the system comprising: 
 an opening in the liner for forming a first edge about the discontinuity;    a mechanical seal circumscribed at an outer perimeter about the discontinuity and located between the liner's first edge and the structural envelope for forming secondary containment between the structural envelope and the liner; and    a secondary seal attached at a perimeter attachment to one of the inner or an outer surface of the structural envelope at the discontinuity, the perimeter attachment being outside the outer perimeter of the mechanical seal for forming a continuous envelope extension from the liner to the discontinuity and for forming secondary containment between the continuous envelope extension and the structural envelope.    
     
     
         2 . The system of  claim 1  wherein the secondary seal is a plate.  
     
     
         3 . The system of  claim 2  wherein the plate is sealably attached at its perimeter attachment to the inner surface of the structural envelope for spacing the discontinuity from the structural envelope, the mechanical seal being between the plate and the liner.  
     
     
         4 . The system of  claim 3  wherein the plate and the structural envelope are sealably attached by a discontinuous weld at the plate's perimeter attachment.  
     
     
         5 . The system of  claim 3  wherein the plate and the structural envelope are sealably attached by a continuous weld at the plate's perimeter attachment.  
     
     
         6 . The system of  claim 2  wherein the plate and the structural envelope are sealably attached by a continuous weld at the plate's perimeter attachment.  
     
     
         7 . The system of  claim 2  wherein the discontinuity penetrates the structural envelope at a first penetration and is attached to the structural envelope at the first penetration, and wherein: 
 the plate is sealably attached at its perimeter attachment to the outer surface of the structural envelope;  
 the discontinuity penetrates the plate at a second penetration and is sealably attached at the second penetration; and  
 the mechanical seal being between the liner and the inner surface of the structural envelope.  
 
     
     
         8 . The system of  claim 7  wherein the structural envelope is a wall of a tank.  
     
     
         9 . The system of  claim 2  wherein a monitoring device is added to between the structural envelope and the plate for detection of a breach of the secondary containment.  
     
     
         10 . The system of  claim 1  wherein the structural envelope is a floor of a tank.  
     
     
         11 . The system of  claim 5  wherein the structural envelope is a floor of a tank.  
     
     
         12 . The system of  claim 1  further comprising: 
 a tertiary seal having a liner boot with an outer edge attached to the liner outside the perimeter of the mechanical seal, the liner boot extending inward to an inner edge; and  
 a second mechanical seal between the liner boot's inner edge and the discontinuity for forming tertiary containment between the continuous envelope extension and the structural envelope.  
 
     
     
         13 . The system of  claim 5  further comprising: 
 a tertiary seal having a liner boot with an outer edge attached to the liner outside the perimeter of the mechanical seal, the liner boot extending inward to an inner edge; and  
 a second mechanical seal between the liner boot's inner edge and the discontinuity for forming tertiary containment between the continuous envelope extension and the structural envelope.  
 
     
     
         14 . Apparatus for sealing a liner about a discontinuity at a structural envelope for containing fluid, the liner forming secondary containment between the liner and an inner surface of the structural envelope, the system comprising: 
 a mechanical seal circumscribed at an outer perimeter about the discontinuity and located an opening in the liner for forming a first edge about the discontinuity, the liner's first edge and the structural envelope for forming secondary containment between the structural envelope and the liner;    a plate attached at a perimeter attachment to one of the inner or an outer surface of the structural envelope at the discontinuity, the perimeter attachment being outside the outer perimeter of the mechanical seal for forming a continuous envelope extension from the liner to the discontinuity and for forming secondary containment between the continuous envelope extension and the structural envelope.