Design and installation of external floating roof tank and external floating roof tank
A concept of external floating roof oil tank:
External floating roof tank known as external floating roof tank is a storage tank without roof design, flaring mouth jar, in design under vertical floating external floating roof, usually for large 20000 cubic meters above storage such as exposure to crude oil, gasoline, kerosene and volatile oil products of steel storage tank, floating roof with liquid storage level rising or falling, external floating roof tank with a floating plate is covered on the surface of the oil, and with the lifting of the oil level, because there is little gas space between the surface of the floating plate and oil, so you can greatly reduce the storage of the evaporation loss of oil.
Two, external floating roof oil tank characteristics:
Floating roof is floating roof tank key core components, divided into "external floating top" and "inner floating roof" two types, floating roof is in the floating top and a fixed cover can enable floating roof itself to avoid exposure to wind and rain, ensure the quality of the oil storage floating roof. Floating roof because it is "floating" in the liquid on the surface of the top cover, the sealing performance is crucial, floating plate mainly uses elastic filler, at the same time in the surrounding with layering and tank wall pressing, and with the bolt and the floating plate is fixed. Floating disc follow the liquid level, then decreased to a certain position about 1.8m, will shore up floating plate so as to keep the position. Therefore, the external floating roof tank has the following advantages:
1, with respect to the top of the floating roof of the fixed top tank is not the evaporation of space, in principle, this will eliminate the so-called big breathing loss". Evaporation not only resulted in the loss of the number of products, but also affected the quality of the products, but also pollute the environment. Space flammable medium and air mixture ratio reached a certain limit, easy to produce explosive. Therefore, the opening of cylindrical steel tank with external floating roof is a necessary measure.
2, the tank shell and the outer floating top floating disc between 100 mm to 500 mm clearance to ensure operation will not chuck. Use edge sealing system to reduce edge evaporation.
Similar to 3, external floating roof structure and inner floating roof, steel tray type, floating cabin type, single or double deck forms, and even using aluminum alloy sandwich structure of floating roof. The supporting legs of the floating roof are usually suspended in a liquid.
4, the floating roof is currently the most suitable for large crude oil storage tanks from 20000, 30000, 50000 cubic meters to 100000 cubic meters, etc..
Three, the difference between inner floating roof tank and outer floating roof storage tank:
The process of sending and receiving of the liquid is the same, the difference between the specific external floating roof storage tank and the fixed top internal floating roof storage tank is as follows: two:
1, the two can be a large number of evaporation loss;
2, the floating tank level on a floating top cover, tank of liquid storage is isolated from the air, reduce air pollution and fire and explosion danger, is easy to ensure the quality of reservoir fluid, especially for senior gasoline and jet fuel and toxic contamination of liquid chemicals on a storage;
3, the fixed roof tank comprises an inner floating roof tank, can effectively prevent the sand blown by wind, snow or dust pollution storage liquid, to ensure the quality of liquid storage in all weather conditions, "all-weather tank said"
4, in the sealing effect under the same conditions, internal floating roof tank with outer floating roof tank compared, further reducing the evaporation loss, which is fixed to the top of the block and fixed roof and inner floating disc between the gas phase layer than external floating roof tank of double disk floating roof has more significant effect of heat insulation.
5. The inner floating roof of the inner floating roof tank is different from that of the external floating roof storage tank, and there is no rain or snow load. Inner floating disc load is small, simple and portable structure, can save the floating disc central drainage pipe, rotational ladder accessories etc.. Easy construction and maintenance, sealing parts of the material can be avoided by sunlight and aging.
6, external floating roof tank and the internal floating roof tank it has many advantages, scope of application is becoming more and more popular, is a future tank and improve the design of inner floating roof tank is so far for the control of the fixed roof tank evaporation loss of the best and the lowest investment method. Inner floating roof tank can be used to store gasoline, jet fuel, easy to volatile oil and aldehydes, alcohols (methanol, ethanol), ketones (acetone) benzene (benzene, toluene, xylene, styrene) etc. liquid chemicals.
Four, the following figure is 30000 cubic meters of crude oil storage tank site construction photos: