RU101023U1 - DOUBLE BOTTOM GROUND VERTICAL RESERVOIR EQUIPPED WITH INSTALLATION OF VAPOR COUPLING FOR PETROLEUM PRODUCTS - Google Patents

Abstract

 A vertical ground tank with a double bottom, equipped with an oil vapor recovery system, containing a fuel tank, an additional piping system for venting vapor and an in-depth tank with low-octane oil product, characterized in that the tank is equipped with a double bottom with stiffeners and a device with a valve to control the level of gas contamination the space between the bottoms, as well as the fact that a pipeline with shutoff valves is installed on the housing of the tank breathing valve united with a buried tank, which is equipped with a receiving device for fuel vapor and a filter-absorber, while the pipeline underground is located in a larger-diameter refrigeration pipe filled with water or coolant.

Description

The proposed utility model relates to devices for storing petroleum products and can be used in the petrochemical and other industries of petroleum products.

The proposed utility model is most applicable for the reception, storage and delivery of gasolines and diesel fuels of various grades at terminals and tank farms equipped with large surface ground vertical steel tanks (PBC).

Air basin pollution at oil depots and terminals occurs when oil vapor is released during “large” and “small” tank breathing, improper installation of breathing equipment, and other reasons. Losses from "big" breaths are due to the displacement of the vapor-air mixture from the reservoir when taking the oil product. In this case, the volume of gas space is reduced, which causes the breathing valve to operate. Losses from "small" breaths are caused by daily fluctuations in temperature and partial pressure of fuel vapor (mainly gasoline) in the gas space of the tank. The temperature of petroleum products stored in ground tanks depends on the ambient temperature. In the summer, oil products in ground-based RCS are heated to 30 degrees Celsius or more. The gas boiling point is 35 degrees [1]. At this temperature, low-boiling gasoline fractions turn into steam and escape into the environment through a breathing valve.

Pollution of the lithosphere and hydrosphere occurs as a result of fuel leaks from reservoirs and pipelines, PBC overflows with oil products, spills from hoses, tankers and other reasons.

If a spill of fuel from the tank’s belts can be detected visually, then the leakage of oil products from the bottom of a ground-based PBC can be determined only by complex diagnostic methods. These methods are associated with the release of the tank from the fuel with the subsequent cleaning of the RVS and are carried out with a certain frequency on average 1 time in 5 years.

Characteristic features in the operation of oil depots are the periodic delivery of oil products to tankers, the receipt of fuel from railway tanks and pipeline transport, as well as the long shelf life of fuel in tanks. This means significant losses from evaporation as a result of "small" breaths, as well as periodic losses from "large" breaths. Hydrocarbon emissions into the atmosphere during the evaporation of petroleum products from reservoirs are very large. This not only leads to fuel losses, but also negatively affects public health.

Combating the loss of fuel from leaks and evaporation is becoming an important environmental and economic challenge.

Known vertical cylindrical steel tank for light petroleum products [2]. This tank has a bottom, a wall and a fixed roof. For receiving and dispensing petroleum products, reservoirs of this type have acceptance pipes. From the outside, valves are connected to them. In order to provide “small” and “large” tank breaths, there is a breathing valve. A metering hatch is installed on the roof of the tank, which serves to measure the level and take fuel samples.

Also on the tank there are monitoring and signaling devices (level gauges, samplers, level indicators, fire fighting devices) and other equipment (manhole, ventilation pipes, safety valves).

The disadvantages of this tank when receiving, storing and issuing petroleum products are:

1. The lack of a device that prevents leakage of fuel from the bottom of the tank.

2. Low efficiency of trapping vapors of oil products at oil depots, especially with "small" tank breathing.

3. A high level of air pollution by vapors of petroleum products.

Also known installation for trapping vapors of petroleum products [3].

Installation for vapor recovery of petroleum products consists of a reservoir with stored oil, a pump, a tank for collecting vapors with double walls, between which cold water flows (refrigerator), and partially filled with low-octane oil (diesel fuel). Inside the reservoir for vapor recovery there are installed: flat horizontal partitions in the layer of low-octane oil product, ultrasonic generators on the outer surface of the inner walls of the reservoir, and activated carbon filter absorber at the outlet of the reservoir.

Installation works as follows.

When excessive pressure is created in the tank (2000 Pa), the pump is turned on through the automatic device, and gaseous hydrocarbons are piped into the tank connected to the cold water supply system. Due to the temperature difference in the tank for petroleum products and in the cooler tank, condensate forms on the inner walls of the bubbles when gaseous hydrocarbons enter the trap tank. Under the action of ultrasonic generators installed on the outer surface of the tank, the bubbles are crushed or completely removed. As a result, the oil product formed on the inner walls of the bubbles is mixed with the low-octane oil product. To increase the path of the passage of bubbles to the upper layers of the low-octane oil product and increase the time of exposure of ultrasonic generators to them, the internal partitions of the tank are installed stepwise, forming a kind of maze. In this case, part of the gaseous hydrocarbons as a result of crushing of the bubbles is absorbed by the low-octane oil product. The insoluble part of the gaseous hydrocarbons at the outlet of the tank is captured by the filter-absorber.

The process of removal of gaseous hydrocarbons from the reservoir occurs until a vacuum (250 Pa) is created in the reservoir. When the vacuum valve is activated, the pump shuts off.

The disadvantages of this installation are:

1. The lack of a device that prevents leakage of fuel from the bottom of the tank.

2. The complexity and high cost of installation.

3. A high probability of failure of the installation elements.

Closest to this problem is the installation of vapor recovery of petroleum products and water removal for ground horizontal steel tanks [4].

In this installation, the tank breathing valves are equipped with a common gas line with non-return valves and shut-off valves for venting oil vapors with “small” and “large” breaths, which is connected to an additional recessed horizontal steel tank with double walls R-5. At the same time, a tank with a capacity of 5000 liters is filled with a low-octane component, equipped with an activated charcoal filter-absorber and an oil vapor receiver with two partitions having cells of different diameters. Pipeline communications are welded to the bottom of the tanks with petroleum products to drain the water, equipped with valves and viewing devices. Pipeline communications are combined into a common line that connects to the double walls of the tank to capture the vapor.

Installation works as follows. With increasing temperature in the tanks, high-octane petroleum products begin to evaporate. Pairs of gasoline raise the plate of the poppet valve and enter the common gas line. In this line, under the vapor pressure, the check valve opens and, with the valve open, the vapor enters the device for receiving oil vapor, equipped with two partitions with openings of various diameters. Vapors pass through partitions with holes of larger and smaller diameters in succession and enter a capture tank, in which water is poured into the interstitial space for cooling.

In this case, gaseous hydrocarbons as a result of lowering the temperature below 35 degrees and crushing the bubbles are absorbed by the low-octane component.

When carrying out "big" breaths associated with the intake of petroleum products, vapors of gasoline and diesel fuel are likewise delivered to a capture tank. In this case, gaseous hydrocarbons as a result of crushing of the bubbles are absorbed by the low-octane component. The insoluble part of the gaseous hydrocarbons at the outlet of the tank is captured by the filter-absorber.

In the process of vapor movement along the gas line, the non-return valve prevents them from entering neighboring tanks.

In winter, due to the low temperature, water is removed from the interstitial space of the capture tank. The disadvantages of this installation are:

1. The lack of a device that prevents leakage of fuel from the bottom of the tank.

2. Low efficiency of cooling vapors of high-octane oil products when passing through the pipeline to the receiving device.

3. The small length of the cooling pipe.

The proposed utility model allows us to solve the problem of increasing the efficiency of preventing leakage of fuel from reservoirs and trapping vapors of oil products stored in ground reservoirs when fumes occur mainly due to changes in temperature (“small” breathing), as well as in connection with the reception of fuel (“large” »Breathing) that occur with a certain frequency associated with the injection of fuels and lubricants.

The solution to this problem is achieved by the fact that the ground vertical tank is equipped with a double bottom with stiffeners and a device with a valve to control the level of gas contamination between the bottoms, as well as the fact that a pipeline with shutoff valves is connected to the tank’s breathing valve body, connected to a recessed tank, which equipped with a receiver for fuel vapors and a filter with an absorber, while the pipeline underground is located in the cooler pipe of a larger diameter meter filled with water or coolant.

These signs are essential for solving the utility model problem, since fuel leaks from the bottom of the tank are prevented, the efficiency of oil vapor capture in ground tanks is increased during storage and reception of fuel, and the reliability of the operation of the tank farm is increased.

The essence of the utility model is illustrated by drawings (figure 1, figure 2,), which depict: sections of the installation and the breathing valve with an additional pipeline.

The proposed tank 1, having a receiving and distributing nozzles 2, a pipe for receiving and dispensing oil products 3, valves 4, light and metering hatches 5, 6, a ventilation pipe 7, an overpressure breathing valve 8, a manhole 9, a working pressure breathing valve 10, an additional pipe 11 is equipped with a non-return valve 12 and a valve 13, which is connected to the housing of the breathing valve 10 and with a recessed horizontal steel tank 14. The tank is equipped with an activated charcoal filter-absorber 15 and a device for receiving vapors of petroleum products 16, which is equipped with two partitions with holes of different diameters 17, 18 for crushing vapor bubbles. The recessed tank is half filled with the low-octane component 19.

An additional pipeline for receiving vapors is equipped with underground piping 20 - a refrigerator 21 filled with water or coolant and equipped with filling and drain valves 22, 23.

The vertical steel tank is mounted with a double bottom 24 with stiffeners 25. The space between the bottoms is equipped with a device 26 with a valve 27 for checking the level of gas contamination with oil products.

The utility model works as follows. Through the intake pipe 3, the oil enters the tank 1. At the same time, the level of fuel 28 begins to increase, and accordingly, the volume of the vapor space 29 decreases. In order to catch the vapors during big breaths, the breathing valve 10, the non-return valve 12 are opened and through a pipe 11 connected to an additional tank 14 equipped with a receiving device 16, the pairs enter the tank with a low-octane component. In this case, part of the gaseous hydrocarbons as a result of the fragmentation of the bubbles by two partitions with holes of different diameters 17, 18 is absorbed by the low-octane oil product 19. The insoluble part of the gaseous hydrocarbons at the outlet of the tank is trapped by the filter-absorber 15.

With "small" breaths associated with temperature changes, with increasing pressure, the breathing valve 10 also opens and oil vapor through line 11 through a receiving device with partitions, enters the reservoir with a low-octane component.

In this case, most of the vapor is converted into liquid due to cooling in the underground section of the pipeline 11 located in the pipeline of the refrigerator 21.

In the event of a fuel leak through the bottom of the tank, the oil product will remain in the tank due to the second bottom 24. The gas contamination of the space between the bottoms is monitored using a device 26 equipped with a valve 27.

If the breathing valve 10 does not work when the pressure rises, or the valve 13 is closed for technical reasons, then the high pressure valve 8 will open to release the vapor-air mixture, which will prevent the destruction of the tank.

Literature

1. A.S.Safonov et al. Automotive fuels. Chemotology. Operational properties. Range. SPb .: NPIKTS, 2002.

2. B.C. Yakovlev. Storage of petroleum products. Problems of environmental protection - M .: Chemistry, 1987.

3. A.S. Kuznetsov and others. Patent for the invention No. 2226122. Installation for collecting vapors of oil products.

4. K.R. Kundrotas, Yu.A. Matveev, et al. Utility Model Patent No. 84253. Installation for vapor recovery of petroleum products and water removal for ground horizontal steel tanks.

5. V.G. Kovalenko. Environmental safety in oil product supply systems and automobile transport. M .: LitNef-teGaz, 2004.

Claims (1)

A vertical ground tank with a double bottom, equipped with an oil vapor recovery system, containing a fuel tank, an additional piping system for venting vapor and an in-depth tank with low-octane oil product, characterized in that the tank is equipped with a double bottom with stiffeners and a device with a valve to control the level of gas contamination the space between the bottoms, as well as the fact that a pipeline with shutoff valves is installed on the housing of the tank breathing valve united with a buried tank, which is equipped with a receiving device for fuel vapor and a filter-absorber, while the pipeline underground is located in a larger-diameter refrigeration pipe filled with water or coolant.