External floating roof tank double deck type an external floating roof tank is a storage tank commonly used to store large quantities of petroleum products such as crude oil or condensate.
Floating roof double deck pontoon.
It consists of an open topped cylindrical steel shell equipped with a roof that floats on the surface of the stored liquid.
Single deck pontoon type figure 1 4 double deck figure 1 5 special buoy and radially reinforced roofs floating roof tank will be further discussed in details in later chapter.
Figure 1 4 single deck pontoon type floating roof bob.
The sketches shown illustrate the above single deck and double deck floating roof with the critical components for these structures.
Ergil storagetech internal floating roofs which minimize the evaporation losses of stored products such as jet fuels gasoline diesel and crude oil can be supplied as aluminium or stainless steel.
Types of external floating roof consist of.
Over the years jm dixon associates has undertaken the design of many floating roofs both double and single deck for world renowned clients such as philips 66 exxon mobil and ineos.
The two preferred configurations for external floating roofs are the double deck and the low single deck with 30 minimum pontoon area.
The low single deck is the more efficient of the two for 30 to 170 foot diameter tanks.
In my humble opinion the double deck arrangement would be a more robust design but may cost extra and a detailed techno economic evaluation would be needed to arrive at the optimum option.
Double deck pontoon roofs which are designed with concentric annular pontoons with radial bulkheads in each pontoon section.
Sketches are provided in the article depicting the pan type pontoon and double deck arrangement for external floating roof tanks.
A double deck type floating roof has two complete decks covering the entire liquid surface.