RU145713U1 - INSTALLATION OF VAPOR COUPLING FROM RAILWAY TANKS WITH A DEVICE FOR PREVENTION OF OVERFLOW OF ABSORBENT AND OIL PRODUCT MIXTURE - Google Patents

Abstract

Installation for vapor recovery from railway tanks with a device for preventing overflows of the mixture of absorbent and oil products, characterized in that the tank of the tank is equipped with an additional high pressure breathing valve, and a common pipe line for vapor removal connected to the double-walled tank is installed on the body of the safety-inlet valve of the tank partially filled with absorbent material, while the vapor recovery line inside the double-walled tank is equipped with a mechanical device In order to prevent flooding-type overflows, and inside the tank, stiffeners with holes were mounted to move the absorbent throughout the volume of the double-walled tank in order to absorb oil vapor.

Description

Installation of vapor recovery from railway tanks with a device to prevent overflow of a mixture of absorbent and oil products

The proposed utility model relates to devices for trapping vapors and can be used in the transportation of oil products by railway tanks in the oil industry.

This utility model is most applicable for capturing vapors of high-octane oil products from railway tanks. High-octane petroleum products primarily include gasoline.

Air basin pollution during the transportation of petroleum products using railway tanks occurs when fuel vapors are released in the process of “small” tank breathing. Losses from "small" breaths are caused by daily fluctuations in temperature and partial pressure of fuel vapors (mainly motor gasolines) in the gas space of the tank. The temperature of oil products transported in railway tanks depends on the ambient temperature. In the summer, oil products in tanks are heated to 30 degrees Celsius or more. The gas boiling point is 35 degrees Celsius [A.S. Safonov et al. Automotive fuels. Chemotology. Operational properties. Range. St. Petersburg: NPIKTS, 2002.]. At this temperature, low-boiling gasoline fractions turn into steam and escape into the environment through a breathing valve.

Calculations show that when transporting only one railway tank filled with motor gas in the amount of 60 tons, more than 300 kg of oil product vapor is released into the atmosphere per year [V.A. Cooper, E.I. Zorya, D.V. Tsagareli. Operations with petroleum products. Gas stations. - M .: “PARITY”, 1999].

Atmospheric pollution by vapors of petroleum products has a harmful effect on the environment and human health. Petroleum product vapors belong to the fourth hazard group. Therefore, the main environmental safety requirements for the transportation of gasoline by rail is to reduce the concentration of oil vapor emitted during the "small" breaths.

Combating the loss of vapor of marketable petroleum products during the transportation of fuel by railway tanks is becoming an important environmental and economic challenge.

Known railway tank for the transport of flammable liquids [V.A. Cooper, E.I. Zorya, D.V. Tsagareli. Operations with petroleum products. Gas stations. - M .: “PARITY”, 1999]. Highly flammable liquids include liquids with a flashpoint of less than 61 degrees Celsius in a closed crucible or less than 66 degrees Celsius in an open crucible. Highly flammable liquids include automobile gasolines, aviation kerosene and diesel fuels [Matveev Yu.A., Varnakov DV The theory of combustion and explosion and fire safety of technological processes. Laboratory workshop. Ulyanovsk. UlSU, 2012].

This tank consists of a railway trolley with wheels, a tank, external and internal stairs, a platform, a hatch, a safety inlet valve, a rod, a universal drain device, a hinged upper and lower covers.

During transportation, "small" breaths are carried out through the safety-inlet valve of the railway tank. At the same time, oil vapor exits the tank into the atmosphere.

Through the hatch, fuel loading measurement and sampling for analysis are carried out. The tank hatch has a hinged lid, bolted.

A universal drain device is located at the bottom of the tank. It has internal and external shutters. An internal shutter is a valve that is opened (closed) with a special key with a rod brought into the hatch of the tank. The external closure is a cover with a sealing ring, pressed in the closed state to the body nozzle with a screw.

The disadvantages of the railway tank for the transport of flammable liquids are:

1. The absence of a vapor recovery unit during the transportation of petroleum products.

2. Air pollution by vapors of petroleum products.

3. Large losses of petroleum products from evaporation during transportation.

Also known is a railway tank for transportation and temporary storage of acidic melange and special products [Specialized tanks for the transport of dangerous goods. Reference manual. M. Publishing house of standards. 1993].

This tank consists of a railway trolley with wheels, a tank, external and internal stairs, a platform, a manhole, a safety inlet valve, a discharge and filling device, a sampling device, a float type filling indicator, a pressure gauge with a valve, a gas valve with a nominal diameter of 70 mm, hinged top and bottom covers.

When transporting a special product, an air filter with a glass wool filter element is installed instead of a gas valve with a nominal diameter of 70 mm.

The tank works as follows.

During transportation, the vapors are captured by an air filter with a glass wool filter element, and with an increase in pressure inside the railway tank associated with an increase in the ambient temperature, “small” breaths are carried out through the safety inlet valve. In this case, the product pairs exit the tank into the atmosphere.

1. The disadvantages of the railway tank for transportation and temporary storage of acidic melange and special products during transportation are:

2. The absence of a vapor recovery unit during product transportation.

3. The release of vapor into the atmosphere through the safety-inlet valve with small breaths.

The need for frequent replacement of the air filter.

Closest to this problem is the installation of vapor recovery during transportation of oil products by railway tanks [Matveev Yu.A. et al. Patent for invention 137527 dated 02.20.2014. Installation for vapor recovery during transportation of oil products by railway tanks].

In this installation, a railroad tank with a safety inlet valve is additionally equipped with a common vapor exhaust pipe with a non-return valve connected to a double-walled tank partially filled with a low-octane component, which is equipped with a receiver for fuel vapor and a safety valve with filter absorber, while the interstitial space of the tank is filled with air.

The low-octane component is used as an absorbent to absorb oil vapor. As a low-octane component, diesel fuel is used.

The tank is equipped with a drain pipe with a valve for draining the mixture of the low-octane component with the oil product, as well as stiffening walls with holes to reduce the speed of movement of the low-octane component and prevent water hammer during the movement of the railway tank, as well as to absorb oil vapor contained in the vapor-air space of the tank.

In order to determine the level of the low-octane component (absorbent) on the double-walled tank there is a metering hatch.

Installation works as follows. With "small" breaths associated with changes in temperature and increased pressure of the vapor space in the tank, the safety inlet valve opens and oil vapor passes through a receiving device with grids with openings of various diameters through a common piping line into a double-walled tank with a low-octane component. In this case, most of the vapor is converted into liquid by cooling in a double-walled tank and absorption by the low-octane component. The cooling by several degrees Celsius in the tank compared with the vapor space of the railway tank is due to the fact that the tank has an interwall space filled with air, which has a low thermal conductivity.

Another part of the oil vapor due to the movement of the low-octane component through the openings of the stiffeners throughout the tank during the movement of the railway tank is absorbed by the low-octane component. The insoluble part of the oil vapor at the outlet of the tank when the safety valve is opened is trapped by the filter-absorber.

The disadvantages of the installation of vapor recovery during transportation of oil products by rail tanks are:

1. The lack of a device to prevent overflow of a mixture of a low-octane component (absorbent) and oil products from a double-walled tank.

2. The lack of an additional breathing valve of high pressure on the railway tank.

The proposed utility model allows us to solve the problem of increasing the efficiency of trapping fuel vapor from railway tanks and to prevent overflow of a mixture of absorbent and oil products from a double-walled tank. A low-octane component (diesel fuel) is used as an absorbent. Diesel fuel has low volatility and mixes well with high-octane oil products such as motor gasolines.

The solution to this problem is achieved by the fact that the tank tank is equipped with an additional high-pressure breathing valve, and a common pipe line for vapor removal is connected to the body of the safety-inlet valve of the tank, connected to a double-walled tank partially filled with absorbent material, while the pipe line for vapor recovery inside the double-walled tank equipped with a mechanical device to prevent flooding-type overflows, and stiffeners mounted inside the tank with holes for moving the absorbent throughout the volume of the double-walled tank in order to absorb oil vapor.

These signs are essential for solving the utility model problem, since the efficiency of oil vapor recovery is increased, overflow of the absorbent-oil mixture is prevented, and the environmental situation in the areas of movement and parking of railway tanks is improved.

The essence of the utility model is illustrated by drawings (Fig. 1, Fig. 2, Fig. 3), which shows a front view of a railway tank, a section of a double-walled tank for vapor recovery, as well as a section of a common pipe line for vapor recovery with a device to prevent overflows in the closed state.

The proposed railway tank having a trolley 1 with wheels 2, a tank 3 with a hatch 4 and a hinged lid 5, an external ladder 6, a platform 7, a safety inlet valve 8, a lower cover for draining oil products 9, couplers 10, additionally on the body the inlet valve, a common vapor exhaust pipe line 11 is installed with a non-return valve 12 connected to a double-walled tank 13 partially filled with absorbent 14, which is equipped with a receiver 15 for fuel vapor and a safety valve 16 with a filter absorber 17, while the interwall space of the tank 13 is filled with air 18.

It should be noted that the receiver of the double-walled tank is equipped with two grids with openings of various diameters of 19.20 for the absorption of oil vapor. The tank is equipped with a drain pipe 21 with a valve 22 for draining the mixture of absorbent with oil, as well as stiffeners 23 with openings 24 to reduce the speed of movement of the absorbent and prevent water hammer during the movement of the railway tank, as well as to absorb oil vapor contained in the vapor-air space of the tank 13.

In order to determine the level of absorbent on the double-walled tank there is a metering hatch 25.

To prevent overflow of the absorbent-oil mixture, the common vapor recovery pipe line 11 inside the double-walled tank 13 has a horizontal section and is equipped with a mechanical device to prevent flooding-type overflows. This device consists of a float 26, a connecting lever 27 and a piston 28. Inside the vapor withdrawal line, a stand 29 is equipped to support the float when the level of the mixture of absorbent with oil 30 is insufficient to raise the float. To block the movement of vapor within the pipeline using the sleeve 31 by the piston, a section with a reduced diameter of the pipe 32 is equipped. The mixture of absorbent and oil product 30 enters the common pipeline for exhausting vapor 11 inside the double-walled tank through openings 33.

For the removal of oil vapor at the closure of the general pipeline exhaust line 11, the tank 3 of the railway tank is equipped with an additional high pressure breathing valve 34 with a filter absorber 17.

The utility model works as follows. With "small" breaths associated with changes in temperature and increased pressure of the steam space in the tank, the safety inlet valve 8 opens and oil vapor flows through a common pipe line 11 through a receiving device 15 with grids having openings of various diameters 19, 20 and enter a double-walled tank 13 with absorbent 14. In this case, most of the vapor is converted into liquid by cooling in a double-walled tank and absorption by the absorbent. The cooling by several degrees Celsius in the tank compared with the vapor space of the railway tank is due to the fact that the tank has an interwall space filled with air 18, which has a low coefficient of thermal conductivity.

Another part of the oil vapor due to the movement of the absorbent through the openings 24 of the stiffening walls 23 throughout the tank during the movement of the railway tank is absorbed by the absorbent 14. The insoluble part of the oil vapor at the outlet of the tank when the safety valve 16 is opened is trapped by the filter-absorber 17.

As the level of the mixture of absorbent with oil 30 increases, the float 26 begins to rise, driving the connecting lever 27, which pushes the piston 28 to close the hole in the section with a reduced diameter of the pipe 32. As a result, the supply of vapor to the double-walled tank is stopped.

After the closure of the common vapor recovery pipe line 11, oil vapor pairs from the tank 3 of the railway tank are vented to the atmosphere through an additional high pressure breathing valve 34 with a filter with an absorber 17.

With the arrival of the railway tank at the collection point, the level of the mixture of absorbent with oil is checked through the metering hatch 25 of the tank and, if necessary, the mixture is drained through the drain pipe 21.

The utility model makes it possible to capture oil vapor from railway tanks, and also significantly reduces the emission of fuel vapor into the atmosphere. In this case, overflows of a mixture of oil vapor with absorbent from a double-walled tank are prevented.

Claims (1)

Installation for vapor recovery from railway tanks with a device for preventing overflows of the mixture of absorbent and oil products, characterized in that the tank of the tank is equipped with an additional high pressure breathing valve, and a common pipe line for vapor removal connected to the double-walled tank is installed on the body of the safety-inlet valve of the tank partially filled with absorbent material, while the vapor recovery line inside the double-walled tank is equipped with a mechanical device In order to prevent flooding-type overflows, and inside the tank, stiffeners with holes were mounted to move the absorbent throughout the volume of the double-walled tank in order to absorb oil vapor.