RU226176U1 - Device for detecting water and oil products in the casemate of an underground vertical tank - Google Patents

Abstract

The utility model relates to devices for storing petroleum products. It can be used in the oil industry. The technical device includes a tank casemate, four optical sensors, communication lines, converters, alarms and video signals. The casemate is equipped with vertical paired optical sensors with the ability to determine water and oil products at various levels in the tank casemate. Moreover, each pair of lower and upper sensors is designed to detect oil products or water, respectively. The upper and lower optical sensors are located at a distance of 20-30 cm from each other. The technical result is achieved by determining water and oil products in the casemate of a tank using optical sensors by changing the refractive index of various liquids and media. In this case, the presence of leaks from the welds and walls of the underground tank is determined, as well as the water in the casemate of the tank is determined for the purpose of its further pumping. Timely removal of water from the casemate helps prevent corrosion of the tank body.

Description

The utility model relates to devices for storing petroleum products. It can be used in the petrochemical and oil production industries.

The proposed utility model is most applicable for storing petroleum products of various grades at oil depots equipped with underground vertical high-capacity steel tanks (VS).

Pollution of the lithosphere and hydrosphere occurs as a result of fuel leaks from tanks and pipelines, overflows of water tanks with petroleum products, spills from hoses, tank trucks and other reasons. If a fuel spill from the belts of an above-ground tank can be detected visually, then a leak of petroleum products from the walls and bottom of an underground RVS can only be determined using complex diagnostic methods.

These methods are associated with emptying the reservoir of fuel with subsequent cleaning of the RVS and are carried out at certain intervals on average once every 5-8 years, depending on the service life of the reservoir [V.N. Zaichenko. New technologies for repairing steel tanks. M.: OJSC "TsNIITEneftekhim", 2002].

During operation, the bottom and walls of an underground RVS are subject to various types of corrosion, which are associated with the presence of sulfur and other aggressive compounds in petroleum products, as well as water in the tank and in the casemate.

The fight against fuel losses from leaks in underground water storage systems is becoming an important environmental and economic task.

A portable device for operational monitoring and diagnostics of the bottoms of vertical steel tanks in operation is also known [D.D. Kostrovsky. Operation of military rocket fuel and fuel storage facilities. M.: Voenizdat, 1992].

The operation of this device is reduced to probing the soil under the bottom of a tank with petroleum products to identify the location of petroleum product leaks at the location where electrical anomalies are detected. Electrical anomalies are associated with increased and decreased resistivity relative to the background value of the soil under the bottom of the tank. The technical device for operational monitoring and diagnostics of the bottoms of vertical steel tanks includes metal probes from 8 to 16 pieces, a cross cable, an electrical quantity meter (ohmmeter), as well as electrical connectors.

The device works as follows. Metal probes are inserted into the soil around the base of the tank at regular intervals. An electrical meter (ohmmeter) is connected to the metal probes using electrical connectors via a crossover cable. Using metal probes and an electrical quantity meter, the soil is probed under the bottom of the tank by measuring the resistance between adjacent pairs of probes in the sequence (1-2, 1-3, 1-4, 1-n, 2-3, 2-4, 2-5 , 2-n, 3-4, etc.). The measurement results are entered into a table. Then, using coefficients, the actual results obtained are recalculated into specific units, which are also entered into the table. After this, the abnormal values of the indicators are selected and the location of the oil product leak is graphically determined from them on the bottom sketch.

The disadvantages of this device when diagnosing the bottom of vertical steel tanks are:

1. Practical inapplicability for underground casemate tanks.

2. Low accuracy of determination in winter, as well as in conditions of high soil moisture.

3. Duration and complexity of determination.

Also known is a ground-based vertical tank for oil and petroleum products, equipped with a stationary bottom diagnostic device [Yu.A. Matveev et al. Utility model patent No. 131014 dated August 10, 2013].

Under the tank, which has receiving and distributing pipes, a pipeline for receiving and dispensing oil and petroleum products, valves, skylights and metering hatches, a ventilation hatch, a high-pressure breathing valve, a manhole, a working pressure breathing valve, the bottom is additionally in the ground at a certain distance from The bottom of the tank is horizontally equipped with metal probes of the first level, perpendicular to which metal probes of the second level are installed, while metal probes of various levels are connected via communication lines to electronic switches having terminals for connecting communication lines of specific metal probes. Electronic switches are connected via a communication line with a device for determining resistance, an ohmmeter, which is connected to a laptop computer.

In order to diagnose the bottom of the tank at a set frequency, which depends on the service life of the tank, using communication lines of electronic switches and an ohmmeter, alternating resistance measurements are made between metal probes of various levels, which are output to the computer. In this case, each measurement corresponds to its own section of the tank bottom.

Values with high resistance refer to the accumulation of petroleum products.

Assessing the resistance values between individual probes of different levels located perpendicular to each other using electronic switches, an ohmmeter and a computer allows you to determine not only the presence of oil leakage from the bottom of the tank, but also to identify the specific location of the leak in order to effectively repair the tank.

The disadvantages of a ground-based vertical tank for oil and petroleum products equipped with a stationary bottom diagnostic device are:

1. Impossibility of application for underground tanks.

2. A large number of metal probes, which increases the metal consumption and cost of the device.

3. Duration and complexity of determination.

A device for diagnosing leaks from the bottom of a ground-based vertical tank for petroleum products using special plates is also known [Yu.A. Matveev et al. Utility model patent No. 149649 dated January 10, 2015].

Under the proposed tank, which has receiving and dispensing pipes, a pipeline for receiving and dispensing oil and petroleum products, a valve, technological hatches, a high and working pressure valve, and the bottom, additionally special plates are laid in the ground horizontally and parallel to each other, which are connected through communication lines to the terminals of the electronic In this case, an ohmmeter is connected to the electronic switch using a communication line, which is connected to the computer via a communication line. Special plates are made of copper and its alloys. The plates are installed in pairs along the diameter of the tank. Moreover, each pair corresponds to a certain section of the tank bottom.

The utility model works as follows. Through the receiving pipeline, the oil product enters the tank.

In order to diagnose the bottom of the tank at a set periodicity, which depends on the service life of the tank, using communication lines of an electronic switch and an ohmmeter, alternating resistance measurements are made with plates, which are output to the computer.

Based on these measurements, not only the leak of fuel from the bottom of the tank is determined, but also the specific location of the leak.

Deviation of values from experimentally obtained during the initial measurement of soil resistance indicates the presence of a leak from the tank. Values with high resistance refer to the accumulation of petroleum products.

The disadvantages of a device for diagnosing leaks from the bottom of a ground-based vertical tank for petroleum products using special plates are:

1. Impossibility of use for underground tanks, as well as for determining water.

2. Insufficient accuracy in determining the location of oil product leakage from the tank.

3. Inability to detect if communication lines or one of the plates under the tank fails.

An automobile tank for petroleum products using optical sensors is also known [Bogdanov A.Yu., Matveev Yu.A. etc. Utility model patent No. 207170 dated 10/15/2021].

On the proposed automobile tank, which has a chassis with wheels, a tank with a neck and a hinged lid, a breathing valve, breakwaters (stiffening partitions), additionally two optical sensors are installed in the front part of the body of the automobile tank.

The first optical sensor is installed at the bottom of the tank. This sensor is designed to detect water. The second sensor is installed at a distance of 30-40 cm from the first sensor and is designed to determine the quality of diesel fuel. In the presence of water and low-quality diesel fuel, the signal from the optical sensor is sent to the converter, and then to the video signal.

The disadvantages of an automobile tank for petroleum products using optical sensors are:

1. Can only be used for automobile tanks.

2. Lack of possibility of application for determining the leakage of petroleum products from the tank.

The closest to this problem is a device for diagnosing leaks from the bottom of a ground-based vertical tank using plates of different metals [Bogdanov A.Yu., Matveev Yu.A. Patent for invention No. 2708540 dated December 9, 2019].

Under the proposed tank, which has standard equipment, three special plates are additionally laid in the ground perpendicular to the bottom of the tank and parallel to each other. Two plates of one metal (copper) and one plate of another metal (aluminum, nickel). The plates are installed at a distance of 10-15 cm from the bottom of the tank, while the distance between the plates themselves is 10 cm.

The plates are connected through communication lines to the terminals of the electronic switch. In this case, a multimeter is connected to the electronic switch using a communication line, which is connected to a computer via a communication line. The multimeter has the ability to determine the values of soil resistance and stress between the plates. The plates are installed along the diameter of the tank in groups of three. Moreover, each group corresponds to a certain section of the tank bottom. The plates are arranged as follows: 1 copper plate, 2 copper plate, 3 aluminum plate.

The utility model works as follows.

Through the receiving pipeline, the oil product enters the tank. In order to diagnose the bottom of the tank at a set periodicity, which depends on the service life of the tank, using the communication lines of an electronic switch and a multimeter, alternate measurements of soil resistance are made between plates of the same metal, which are output to the computer. If the resistance values deviate from those experimentally obtained during the initial soil measurement, the operator carries out additional measurements. The soil stresses between plates of different metals are determined.

By measuring the resistance and stress of the soil between the plates, not only fuel leakage from the bottom of the tank is determined, but also its specific location in order to effectively repair the tank.

Deviation of values from those experimentally obtained during the initial measurement of soil resistances and stresses indicates the presence of a leak from the tank. Values with high resistance and low voltage refer to the accumulation of petroleum products.

The disadvantages of a device for diagnosing leaks from the bottom of a ground-based vertical tank using plates of different metals are:

1. Impossibility of use for underground tanks, as well as for determining water.

2. Insufficient accuracy in determining the location of oil product leakage from the tank.

3. Inability to detect if communication lines or one of the plates under the tank fails.

The solution to this problem is achieved by the fact that in the casemate of an underground tank, four optical sensors are installed vertically and in pairs at a certain distance from each other and from the base of the casemate, which are connected by communication lines to converters, video signals and alarms, and also by the fact that each pair of sensors is made with the ability to determine water and oil products at different levels, respectively.

These features are essential for solving the problem of the utility model, since the efficiency of determining fuel leaks from welds and walls of an underground tank without releasing it increases, it becomes possible to determine water in the casemate of the tank for the purpose of its further pumping, and the reliability and simplicity of the device also increases.

The essence of the utility model is illustrated by drawings (Fig. 1, Fig. 2), which show: a section of an underground tank, an arrangement diagram of optical sensors connected to converters, as well as audio and video signals.

Casemates are used for the construction of underground vertical steel tanks. [Fuel service warehouses. The textbook is edited by L.G. Kuts. Ulyanovsk UVVTU, 2010]. The walls of underground casemates are made of reinforced concrete or concrete blocks. The distance from the casemate wall to the tank body must be at least 0.8 meters.

In casemate 1 of a vertical steel tank 2, which has standard equipment, four optical sensors 3 are additionally installed. Optical sensors are installed vertically in the lower part of the casemate in pairs.

The two lower sensors are installed at a distance of 3-5 cm from the concrete base of casemate 4. The two upper sensors are installed at a distance of 20-30 cm from the prism of the lower sensors. In each pair, one sensor is designed to determine oil product 5, and the second sensor is intended to determine water. Taking into account the sensor length of 30-40 cm, the prisms of the upper sensors are located at a distance of 25-35 cm from the lower base of the casemate. The cables from the optical sensors are placed in sealed waterproof cable channels 6. The optical sensors are connected by communication lines 7 to converters 8. In this case, the converter from the lower and upper sensors for determining water is connected to video signals 9, and the sensors for determining oil products are connected to audio signals 10.

Optical sensors are used to determine the levels of various liquids and media in reservoirs, tanks, and other structures. The operating principle of optical sensors is based on the different refraction of light when passing through a prism (hemisphere) in different liquids or media. The optical sensor includes a housing, a prism, an LED, a photodetector and a measuring electronic circuit. Water, oil products, air. In particular, water has a refractive index of 1.33, petroleum products 1.41-1.47, and air 1.

For the purpose of installing and testing optical sensors 3, casemate 1 is equipped with a hatch 11 on top and a ladder 12 inside.

It should be noted that the reservoir 2, depending on the volume, is located under the earth's surface 13 at a depth of 6-12 meters.

Water in the casemate may appear as a result of spring floods; it is possible that groundwater may enter the casemate. The presence of water in the casemate is not permissible, since it causes corrosion processes in the welds and walls of the tank. Oil product entering the casemate is associated with its leakage through welds, tank walls and valve 14.

The possibility of oil product entering the casemate along with melt and groundwater cannot be ruled out when oil product leaks from under the bottom of the tank.

The utility model works as follows.

Through the receiving pipeline 15 and the valve 14, oil product 5 enters tank 2. If oil product leaks from the tank and the oil product reaches the lower optical sensor 3, the sensor will show a refractive index value different from the refractive index of air and water. This value of the refractive index through the communication line 7 is sent to the converter 8 for the oil product, and then to the sound signal 10. This means that the oil product is leaking from the tank and entering the casemate. When the oil product reaches the upper sensor, a second sound signal is activated in the form of a siren. This event indicates a major accident associated with the destruction of the reservoir.

If water enters and reaches the level of the lower corresponding optical sensor, sensor 3 will display a refractive index value different from that of air and oil products. This refractive index value is supplied through communication line 7 to water converter 8, and then to video signal 9, for example, in the form of a yellow lamp lighting up. When the water reaches the upper corresponding sensor, a second video signal turns on, in the form of a red light coming on. This event indicates the need to pump water out of the casemate with a deep pump.

The utility model makes it possible to timely determine the presence of water and oil products in the casemate of an underground tank. The appearance of an oil product in the casemate indicates the presence of a leak from the tank.

Removing water from the casemate helps prevent corrosion of the tank body.

Claims (1)

A device for detecting water and oil products, designed to be located in the casemate of an underground vertical tank containing a pipeline, a valve, and communication lines, characterized in that the device is made in the form of four optical sensors, with the ability to be installed in the casemate of an underground tank vertically and in pairs at a certain distance from each other from each other and from the base of the casemate, while the optical sensors are connected by communication lines to converters, video signals and alarms, and also by the fact that each pair of sensors is configured to detect water and oil products at different levels, respectively.