Oil production today is quite developed. To create a trunk oil pipeline, there are several prerequisites, including the creation of a tank farm. But what is it? In itself, such a fleet is a group of several separate reservoirs used to store oil, combined into one unit.
general characteristics
Tank parks can vary in design and performance. It depends on several factors. One of the most important factors is the group of oil products that will be stored inside the tank. The second reason for the change in design is the volume of the stored product (both collected raw materials and shipped are taken into account). Despite this, all tank farms will be characterized by the fact that they are created to perform several of the following tasks:
- After collecting the capacity, it is convenient to keep a record of all petroleum products.
- Naturally, they are intended for direct storage of products.
- In these tanks, a compounding process takes place. It should be carried out in accordance with all applicable standards, as well as in accordance with all the rules of mixing different varieties of petroleum products.
Who uses most often?
The main users of tank farms today are mining companies, oil product pumping complexes, and oil bases. All the enterprises that were listed use reservoirs for storing hydrocarbon raw materials, but only after passing the audit, as required by the regulations.
In the Russian Federation, the company Spetsneftemash is engaged in the production of quality equipment. All structural elements in the assembly are leakproof, characterized by high quality and meet all the requirements of the Russian and international standards that establish the rules for such tanks.
Design rules
Oil tank farms are created according to several standards. This list includes the following documents: GOST 1510-84, GOST 30852.9-2002, SNiP 2.11.03-93.
These documents determine both the technical and material requirements that apply to the device. Subject to these rules, it is easy to achieve the continuous operation of the oil tank farm.
If it is necessary to arrange the supply of petroleum products to the group of reservoirs by gravity, then for this you will have to look for a terrain with a flat topography. However, when choosing a place, do not forget about the fire safety rules that come to the fore when it comes to oil. According to one of the rules, storage tanks for this substance should be installed in lowlands.
Design sequence
In order to create a working and safe scheme of the oil products tank farm, the development process should be carried out in accordance with a specific plan. This process itself is complex and takes place in several stages.
At the first stage, it is necessary to form a direct group of tanks that will be designed for storage, transfer, shipment of both oil and oil products. At the same stage, additional systems such as protective, automated should be developed. At the same time, a project is being introduced to connect pumping equipment for tanks and tank farms, if necessary.
At the second stage, it is necessary to engage in the design of each of the tanks separately, as well as introduce into the project a communication device between these tanks. When working with a project to create such a park, you should be guided by two more documents - the master plan of the mining facility itself and the installation plan.
Vertical type of tank
There are many different types of tanks that are used to store oil. The most common among all the rest were vertical steel tanks, briefly called PBC.
The device of these containers is quite simple. They are cylindrical vertical containers of the required height, which are welded from steel sheets, whose thickness is in the range from 10 to 25 mm. They are constructed in such a way that the long side of each sheet is placed horizontally. A number of such sheets will be called a tank belt. As for the roof, then the store with a small volume, it will rely on farms. If the volume is large, then the roof will rest on the central pillar.
The bottom for such tanks is welded, and it is mounted on a sand cushion. In addition, it is designed so that the slope of the bottom is from the center to the periphery. This is necessary to remove the bottom water as best as possible. As for the height of the storages, it can be 9, 12 or even 18 meters. The diameter can be from 20 to 60 meters. Depending on these two parameters, the total volume of the tank farm will naturally change.
In addition, the storage capacity will also depend on its purpose and may be 1, 3, 5, 10, 20, 50 thousand m 3 . In this case, the internal overpressure should not exceed 0.02 atm.
Other varieties of oil storage
The general classification includes only 4 different groups of tanks:
- Overhead type of capacity. It is to this type that vertical steel tanks belong. Here you can add that inside them special pontoons from different materials can be located. Their main purpose is to reduce oil losses during evaporation.
- Next is the ground-based type of equipment, which is similar to above-ground, by the method of its execution and design.
- Semi-underground storage facilities are considered a separate category. The installation of such tanks takes place with the help of a material such as reinforced concrete. If necessary, such a tank can be lined with steel sheet from the inside.
- The latter type is underground and underwater storage systems. The main and distinctive feature is that evaporation losses are completely absent, since the storage is either under the water column or underground. Because of this, they are characterized by the highest preservation of raw materials.
If we talk about volumes, the first three categories of the park are characterized by the fact that each individual storage facility can accommodate no more than 200 thousand cubic meters of oil or oil products.
Tank operation. Features
Further, it is worth mentioning that the work of the tank farm in the usual sense of the word is absent. That is, the storages themselves do not perform any actions, they just store oil products. However, there is a certain set of additional equipment that the park is equipped with. Thanks to these devices capacities become more "active".
Storage Equipment
In the general set for storages, the following devices are used:
- For filling and emptying of the tank, piping acceptance pipes are used.
- To determine the level of matter and sampling there is a metering hatch.
- Tank parks for oil and petroleum products are additionally equipped with level gauges for automatic measurement of the amount of substance. The level gauges themselves are either ultrasonic or float-operated.
- Separately, it is worth highlighting a device called a respiratory fuse. This fuse protects the tank against excessive increase or decrease in pressure in the gas space. In addition, it plays an important role during the big "breaths" of the store, when it is filled or empty. In such cases, the device reduces oil loss.
- Mandatory is a fire fuse. It is intended to protect the interior from sparks and open fire inside.
- Siphon faucet, used for lowering commercial water.
- During storage, oil will precipitate, which is washed out using a special device.
- At the bottom there is a special manhole. It is intended for ventilation of the internal space of the tank before starting repair work.
Precautions
Since oil is a very dangerous substance, all equipment must be manufactured in such a way as to create a minimum risk of an accident. To do this, the enterprise engaged in the production of reservoirs for parks must take care of the installation of protection and security. Tank protection should perform several basic tasks:
- the security system must prevent the spread of oil products and the oil itself throughout the tank farm;
- product ignition prophylaxis;
- ensuring the protection of employees working at the tank farm from the effects of fire and poisoning.
Firefighting. How to prevent trouble?
Naturally, the question of extinguishing tank farms is the most relevant. Firstly, all structures of this type are necessarily equipped with a fire extinguishing system. It notifies of a fire, a leak, the occurrence of another emergency. When such a signal arrives at the control room, a team of firefighters immediately leaves for the place. For all fire extinguishing work in tank farms, a separate employee is responsible who occupies the position of leader in solving this problem. The fire brigade must also arrive at the scene of the accident within 1 hour from the receipt of the signal from the protective system.
Ways to eliminate the fire
At such facilities, two methods of extinguishing fire are used - sublayer and surface. What unites these two methods is that both will use foam type fire extinguishers. They reduce the temperature of the substance, do not allow the fire to spread beyond the source of ignition.
The supply of extinguishing agent must necessarily exceed the amount that is designed to extinguish the fire within 15 minutes. In addition, the allowable multiplicity of these substances should be medium or low. The use of foam extinguishers is also required because the foam is able to form a film on the surface of the oil, which reduces or prevents the escape of combustible vapors during a fire.
It is worth saying that the sublayer method of extinguishing a fire is most common. It implies the use of a stationary type fire extinguishing system or with the help of an elastic sleeve. In this case, the fire extinguishing agent will be sent directly to the layers of oil products. In addition, the main advantage of this method is the absence of danger to the foam generators themselves.