A storage tank is a tank designed for storing liquid substances. Although it is mainly used in the petroleum industry (petrol tanks) , it can also be used in other industries, for example, it is used in the food industry (oil storage tanks) and the fertilizer industry. A storage container is a container that holds liquids, compressed gases or liquids used for short or long term hot or cold storage. The design and construction of storage tanks are carried out according to international standards. Stored products usually consist of petroleum derivatives or chemicals used in the industry. The most preferred standards for storage tank fabricators are API 650 and API 620 standards published by the American Petroleum Institute.
In industry, storage tanks operate under little or no pressure, which distinguishes them from pressure vessels. Storage tanks are usually cylindrical in shape, with a flat bottom and fixed breakable or perpendicular to the floor with a floating roof. There are many environmental regulations for the design and operation of storage tanks, which are usually applied depending on the nature of the liquid contained in them. Aboveground storage tanks differ from underground tanks in the applicable regulatory types. Above ground storage tanks can be used to hold materials such as oil, waste, water, chemicals and other hazardous materials while meeting stringent industry standards and regulations. Particular care should be taken for its safety, since most liquids can spill out, evaporate or leak even through the smallest opening. This usually involves making an embankment or a set of enclosures around the tank so that any leaks can be safely contained. Some storage tanks require a fixed roof and a floating roof as an extra to the structure or instead. This floating roof rises and falls relative to the liquid level in the tank, reducing the vapor space above the liquid level. Floating roofs are considered a safety requirement and pollution prevention measure for many industries, including oil refining.
Storage Tanks For Refineries
The tank of a particular liquid is selected according to the flash point of that substance. Usually, there are tanks with fixed ceilings and tanks with floating ceilings in refineries and especially for liquid fuels.
- Fixed-roofed tanks have a very high flash point. There are shapes such as cone roofs, dome roofs and umbrella roofs. It is insulated to prevent the clogging of some materials that receive heat from the steam coils in the tank. Dome-roofed tanks are used for tanks with a storage pressure slightly higher than that of the atmosphere, for example, used in slop oils.
- Floating roof tanks are generally external floating roof tanks and are divided into internal surface roofed types.
Floating roof tanks are used for gasoline with low flash point liquids such as ethanol. These tanks are nothing more than cone-roofed tanks with a floating roof that moves up and down with the level of liquid in them. This floating roof traps steam from low-flashpoint fuels. Floating roofs are supported by legs or cables on which they sit. One of the best types found in mining areas are open-roofed type tanks, usually for storing ore slurries. These are the simplest and shortest-lasting storage tanks to produce. As for fuels, because their flash points are very low, LPG, hydrogen, hexane, nitrogen, oxygen, etc. tanks for storage are usually spherical.
Types of Storage Tanks
- Atmospheric: Atmospheric storage tanks is a container of liquid contained at atmospheric pressure in it. The main design codes for welded atmospheric tanks are API 650 and API 620. API 653 is used for the analysis of in-service storage tanks.
- High Pressure: It must be made to withstand pressures such as a liquefied gas such as hydrogen or chlorine, or compressed natural gas. These tanks can be called cylinders, and since they are pressure vessels, they are sometimes excluded from the class of “tanks”.
- Thermal Storage Tanks: For seasonal heat energy storage, large insulated and shielded water tanks are used to store the thermal heat of the sun throughout the year. Related technology has become widespread in district heating systems, especially in Denmark. Ice and slush tanks are used for short-term colds for air conditioning, allowing refrigeration equipment to work at night, when electric power is cheaper.
- Milk Tank: A bulk milk cooling tank in dairy farming is a large storage tank for cooling and keeping milk at a cold temperature until it is received by a milk carrier. Since milk is separated from the breast at about 35 ° C and retains its natural resistance to bacteria after extraction, milk tanks are used for rapid cooling to a storage temperature of about 4 °C to 6 ° C, preventing further growth of microorganisms. It is usually made of stainless steel and is used to store raw milk on the farm in good condition every day.
- Oil Storage Tank: The process of transferring oils is provided by means of wall pumps or stainless valves. Weighing groups are placed on the foot parts of the boiler. These systems, which determine the product’s amount, provide users convenience.
Storage Tanks Building Materials
Steel and concrete remain one of the most popular options for tanks, while glass-reinforced plastic, thermoplastic and polyethylene tanks are growing in popularity. They offer lower construction costs and higher chemical resistance, especially for the storage of special chemicals. Several relevant standards give recommendations on wall thickness, quality control procedures, and tests for various controllers.
Storage tanks are sealed storage vehicles for substances to be stored according to the standards. The requirements for storage tanks are different according to the material properties of the materials to be stored. In addition, storage tanks should be designed taking into account the processes before and after storage systems.
Given a large number of relevant criteria, it is necessary to have a serious experience in the selection of the optimal storage system. Planning and design of storage systems require the use of company-specific approaches. Our YENA Engineering specialists have a level of technical knowledge related to storage systems that provide solutions to both simple and complex needs. There are many systems made of steel in our product range. Take advantage of our experience and call us for our special solutions for you!