Flexible (elastic) tanks have been especially developed for transportation of petroleum products by sea and for their storage under water. Such storage reservoirs are primarily made of materials with synthetic fibers, rubbers and plastics. Preference is often given to rubber materials obtained by vulcanization of rubber mixtures.
Nylon, PVC, polyester, fluorine-containing fibers, polypropylene and copolymer are the most common synthetic fibers. They have high strength and resistance to abrasion, influence of acids, oxidizing agents, light and atmosphere.
Synthetic rubber elastic tanks
Prior to manufacturing flexible storage reservoirs, both natural and synthetic rubber should be subjected to hot vulcanization that helps to receive durable material. Rubber mixture which is based on butadiene-acrylonitrile and polychloroprene caoutchouc has especially good features.
Plastic tanks for oil and oil-products are also widespread along with rubber storage reservoirs. Plastic coatings show good strength and resistance to the impact of most petroleum products and chemicals.
Elastic tanks are most commonly made in the form of a cylinder. Conical extensions are covered with special shells made of metal or fiberglass to strengthen them.
Ground tanks have impermeable elastic covering. The holding capacity of such tanks depends on their cross-section shape and length. But there is a limitation: liquid surface area should not exceed 3000 m3. In practice, the holding capacity of ground tanks can vary from 1900 to 33000 gallons. Ground tanks require precast concrete constructions regardless of their capacity.
Preparation and homogenization of mixed fuels for storage in flexible tanks
For better storage in elastic tanks, fuel is prepared from relatively inexpensive primary components. The quality of the finished product (and so fuel economy) depends on blending equipment.
Blending units have a special hydrodynamic blender. All the components are simultaneously supplied into a common reservoir. High quality commercial gasolines such as 92 RON, 92 RON EC, 95 RON, 95 RON EC, 98 RON and 98 RON EC are poured into a flexible tank for oil-products storage after blending.
The cost of mixed gasoline depends on the cost of starting components: alcohols, gaseous stable gasolines, fuel economy, straight-run gasoline, lower octane gasolines and biological components of motor fuels as well as gasoline octane boosters.
The main advantages of GlobeCore blending technologies are a precise control of each component and reduced blending cycle. Mixed fuels that are prepared with the help of blending units, are characterized by high homogeneity, they do not settle or separate in long storage.