Pre-isolated storage tank for cold liquids

Abstract

A storage tank with a pre-insulated outer tank has been described, and a method for building such. For building a wall of an outer tank, a formwork is erected with an inner partition to which PVC-foam plates have been attached, which at their inner surface are provided with a coating provided with gravel. Subsequently, concrete is poured into the inner formwork space, which concrete attaches firmly to the gravel sticking out of the coating. On a floor, a coating layer is applied, over which a layer of PVC-foam plates is applied. Subsequently, a secondary monolithic coating layer is sprayed over those PVC-foam plates and onto the inner surface of the coated PVC-plates 10 of the wall.

1 . Insulation plate, comprising a plate of PVC-foam and a coating of a two-component poly-urethane material applied on at least one main surface thereof.  
   
   
       2 . Insulation plate according to  claim 1 , wherein the PVC-foam and the coating attach well to each other and have mutually substantially equal or at least comparable contraction coefficients.  
   
   
       3 . Insulation plate according to  claim 1 , wherein the coating has been chosen to be liquid-tight and vapor-tight.  
   
   
       4 . Insulation plate according to  claim 1 , wherein the PVC-foam plate has a step profile at least two opposite side edges and preferably at all opposite side edges.  
   
   
       5 . Insulation plate according to  claim 1 , wherein the coating is monolithic.  
   
   
       6 . Insulation plate according to  claim 1 , wherein gravel is arranged in the coating.  
   
   
       7 . Method for manufacturing an insulation plate according to  claim 1 , wherein a two-component poly-urethane coating material is sprayed on at least one main surface of a plate of PVC-foam, and wherein gravel is optionally scattered on the still wet coating material.  
   
   
       8 . Insulated concrete construction element, comprising a concrete body and an insulation plate according to  claim 6  against that body, wherein the coating of the insulation plate provided with gravel is directed towards the concrete body and is attached thereto.  
   
   
       9 . Method for manufacturing an insulated concrete construction element according to  claim 8 , wherein the insulation plate is placed in a mold or formwork or is used as part of a mold or formwork, with the coating layer directed towards the interior of this mold or formwork; and wherein subsequently concrete is poured into this mould or formwork, such that this concrete comes into contact with the gravel.  
   
   
       10 . Method for building an outer tank of a storage tank, meant for storing cold liquids, comprising: 
 erecting a formwork for a wall, which formwork comprises an outer partition and an inner partition, which are placed at mutually radial distance with respect to each other and thus define an inner formwork space, wherein insulation plates are provided having a plate of PVC-foam and a coating of a two-component poly-urethane material applied on at least one main surface thereof and wherein gravel is arranged in the coating and insulation plates are attached to the inner partition, with the coating directed towards the inner formwork space;    pouring concrete into the inner formwork space; and    taking away the formwork after sufficient hardening of the concrete, wherein the insulation plate remain behind against the concrete of the wall.    
   
   
       11 . Method according to  claim 10 , wherein the formwork is a sliding formwork and the wall is built in subsequent ring-shaped wall section, wherein always a new insulation plate at its lower edge is attached to its lower neighbor and at its upper edge is attached to an inner partition, wherein concrete for a ring-shaped wall section is poured into an ring-shaped formwork part, wherein at least said attachment of this upper edge is left free, and wherein, after sufficient hardening of the concrete, said attachment is disconnected and the inner partition is taken away from the insulation plate.  
   
   
       12 . Method according to  claim 10 , further comprising the steps of: 
 spraying a coating layer on a floor;    subsequently applying a layer of PVC-foam plates;    spraying a secondary monolithic coating layer onto those PVC-foam plates and onto the inner surface of the coated PVC-plates of the wall.    
   
   
       13 . Method according to  claim 12 , wherein the secondary monolithic coating layer is sprayed in horizontal tracks connecting to each other.  
   
   
       14 . Method according to  claim 13 , wherein the secondary monolithic coating layer is sprayed with the aid of a vehicle guided along the wall, provided with at least one spray nozzle.  
   
   
       15 . Method according to  claim 14 , wherein the displacement direction of this vehicle for subsequent tracks is alternatively left and right.  
   
   
       16 . Method according to  claim 14 , wherein the thickness of the sprayed coating layer is checked with the aid of a coating thickness sensor.  
   
   
       17 . Method according to  claim 14 , wherein the completion of a track is established with the aid of a camera.  
   
   
       18 . Coating application installation, comprising: 
 a guiding system meant for positioning in circumferential direction along the wall of a storage tank;    a vehicle displaceable along this guiding system;    at least one, but preferably three placed above each other, spray nozzle(s) associated with the vehicle;    drive means for displacing the vehicle along the guiding means;    vertical displacement means for changing the vertical position of the vehicle and maintaining a vertical position once chosen;    a control member for controlling said drive means and said vertical displacement means.    
   
   
       19 . Installation according to  claim 18 , wherein the vehicle is provided with a thickness sensor which is adapted to give to the control member a signal which is representative for the thickness of the applied coating layer.  
   
   
       20 . Installation according to  claim 18 , wherein the vehicle is provided with a camera which is provided with suitable image processing software, for recognizing that the beginning of the coating layer just applied is reached, and which sends to the control member a corresponding signal.