Floating apron for controlling evapn. in storage tanks - is mfd. from corrosion resistant, non-submersible, impermeable modules with foam plastic core in plastic-covered flexible metal envelope

摘要

A modular structure for making a floating apron to control the evapn. of a liq. in a storage tank comprises a core made of foam plastic e.g. polyurethane and an envelope. The envelope encloses the core and forms a barrier which prevents the core absorbing liq. or vapour. It consists of a layer of flexible metal which is a good conductor of electricity, entirely covered with an outer layer of plastic material to prevent corrosion of the metal by the stored material. This metallic part can be fitted with an inner layer of plastic material to increase adherence between the core and the metal. It is preferable however to treat this inner layer e.g. by flame treatment to ensure liaison between the core and the coating. Problems associated with absorption of liq. by the polyurethane, corrosion of the metal layer, sinking of the apron and diminishing of rigidity are avoided. The floating apron made from the modules according to the invention cannot be attacked by the contents of the tank, cannot be submerged and is impermeable to liquids or vapours, while being economical and simple to install.