FR3120364A1 - Purge cart, assembly comprising the cart and a pilot meter, and related method. - Google Patents

Abstract

Purge carriage, assembly comprising the carriage and a pilot meter, and associated method Purge carriage (14) intended to make it possible to purge and fill a pilot meter (12), the purge carriage comprising: - a frame (44), and wheels (46), - a plurality of tanks (48A, 48B, 48C) fixed to the frame to respectively contain a plurality of qualities of hydrocarbon (50A, 50B, 50C) distinct from each other and liquid at a temperature 25°C and a pressure of 101325 Pa, and to respectively define a plurality of gas blankets (52A, 52B, 52C), - a pressurization system (54) adapted to inject a pressurized gas (56) selectively into one any of the gas overheads, and - an exchange system (58) adapted to selectively conduct any one of the hydrocarbon qualities from one of the reservoirs to the pilot meter, and adapted to selectively receive in one of the reservoirs any of the hydrocarbon grades in p origin of the pilot meter. Figure for abstract: Figure 1

Description

Purge cart, assembly comprising the cart and a pilot meter, and associated method.

The present invention is in the field of hydrocarbon metering, for example gasoline or diesel. It concerns a device adapted to facilitate the use of a reference meter, also called a "pilot meter".

The invention also relates to an assembly comprising this device and the pilot meter, as well as a corresponding method.

The pilot meter is generally a mobile device, allowing control of industrial measuring systems, in particular for the loading of tank trucks or wagons with hydrocarbons. The pilot meter makes it possible to control the accuracy or the drifts of the measuring systems.

The pilot meter is advantageously used without interrupting the operating process and is installed in series between a loading arm and the truck or wagon coupler. The pilot meter makes it possible to carry out a volume measurement simultaneously with that carried out by the loading installation in order to ensure that the latter remains within the tolerances of accuracy of measurement.

The pilot meter defines a path for the mixture of hydrocarbons to be measured, this path comprising for example a turbine and a computer, and defining one or more high points and low points. This path typically has a volume of a few tens of liters. Also, before its use, the pilot meter is pre-filled manually with the mixture of hydrocarbons, without the presence of air to properly respect metrologically a constant volume and without the presence of air in the tooling. After its use (and for product quality reasons this time), the pilot meter is carefully emptied of the mixture of hydrocarbons, so that it can then be used to carry out measurements relating to another mixture of hydrocarbons.

For example, after carrying out the calibration of a gasoline measuring system, the pilot meter is purged of the gasoline it contains, before filling it with diesel to carry out a calibration relating to a measuring system of diesel fuel. Indeed, for obvious reasons, the mixing of petrol and diesel is not permitted during loading operations.

These successive operations of filling and purging the pilot meter are carried out thanks to several tanks or autonomous auxiliary sources supplying the different qualities of hydrocarbon. Each quality of hydrocarbon purged is collected in a dedicated tank for the duration of the control campaign, then treated as waste at the end of the campaign.

An object of the invention is therefore to simplify the calibration operations, in order to reduce the cost thereof, without reducing the precision of the calibration, nor increasing the risk of mixing between the loaded products, and in compliance with the constraints related to the safety of people and installations.

To this end, the subject of the invention is a purge carriage intended to make it possible to purge and fill a pilot meter, the purge carriage comprising:

- a frame, and wheels mounted on the frame for rolling on the ground,

- a plurality of tanks fixed to the frame and adapted to respectively contain a plurality of hydrocarbon qualities distinct from each other and liquid at a temperature of 25°C and a pressure of 101325 Pa, and to respectively define a plurality of gaseous skies above hydrocarbon grades,

- a pressurization system suitable for injecting a pressurized gas selectively into any of the gaseous overheads, and

- an exchange system adapted to selectively conduct any one of the hydrocarbon qualities from one of the tanks to the pilot meter to fill the pilot meter, and adapted to selectively receive in one of the tanks any hydrocarbon grades from the pilot meter to purge the pilot meter.

According to particular embodiments, the purge carriage comprises one or more of the following characteristics, taken separately or in all technically possible combinations:

- the pressurization system comprises at least one bottle containing the pressurized gas, the bottle resting on the frame;

- the pressurized gas comprises by volume at least 95%, preferably at least 99%, of nitrogen;

- the tanks respectively comprise a plurality of inlets for the pressurized gas, the pressurization system further comprising: a pipe, a regulator mounted on the bottle, a flexible pipe fluidly connecting the pipe and the regulator, and a plurality of pipes fluidically connecting the pipe respectively to the inlets for the pressurized gas, each of the pipes comprising a shut-off valve;

- the pressurization system is also suitable for venting any of the tanks, and/or for sending pressurized gas to the pilot meter;

- the tanks respectively comprise outlets for the hydrocarbon qualities, the exchange system comprising: a plurality of pipes, each of the pipes comprising a first end connected respectively to one of the outlets, a second end opposite the first end , and a shutter valve located between the first end and the second end; and at least one flexible pipe adapted to fluidically connect the second end of any one of the pipes and the pilot meter;

- the tanks have a capacity of between 25 and 100 litres; and

- each of the reservoirs comprises a member adapted to indicate a level of liquid in said reservoir.

The invention also relates to an assembly comprising a pilot meter and a purge carriage as described above, for purging and filling the pilot meter.

The invention also relates to a method implementing an assembly as described above and comprising the following steps:

- injection by the pressurization system of gas under pressure selectively in any of the gaseous skies,

- filling of the pilot meter selectively by one of the hydrocarbon qualities via the exchange system,

- selective reception in one of the tanks of any of the hydrocarbon qualities from the pilot meter; and

- purge of the pilot meter.

The invention will be better understood on reading the following description, given solely by way of example and made with reference to the appended drawings, in which:

the is a schematic side view of an assembly comprising a purge carriage according to the invention, the pilot meter not being detailed,

the is a schematic side view of the assembly shown in the , the purge carriage not being detailed, and

the is a schematic perspective view of the purge carriage shown in Figures 1 and 2.

With reference to Figures 1 and 2, an assembly 10 according to the invention is described.

The assembly 10 comprises a pilot meter 12, and a purge carriage 14 according to the invention, to purge and fill the pilot meter. Set 10 is intended to allow calibration or control of a measuring set (not shown) with which it is in principle mounted in series. The measuring system is for example intended to measure a volume of a hydrocarbon quality, in particular for the loading of tank trucks or wagons (not shown).

“Hydrocarbon grade” here means a given mixture of hydrocarbons. Gas oil and gasoline are, for example, hydrocarbon qualities.

As seen on the , the pilot meter 12 comprises for example a frame 16 equipped with wheels 18, and a path 20 for a hydrocarbon quality 22. In the example, the pilot meter 12 also comprises a supply unit 24, a drain air 26, preferably an intermediate computer 28, and a display computer 30 transactional. The pilot meter 12 advantageously comprises a drainage and filling system 31.

In the example, the path 20 successively comprises, in the direction of circulation of the hydrocarbon quality 22, an inlet 32, a sensor 34, a turbine 36, a valve 38 for regulating and maintaining the pressure, and a output 40 for hydrocarbon grade 22.

Path 20 defines, for example, a first low point A located between the inlet and sensor 34, a second low point B located between turbine 36 and valve 38, and a third low point C located downstream of valve 38.

The low points A, B and C correspond for example to tappings of the drainage and filling system 31 on the path 20. The points A, B and C are for example located substantially at the same level vertically.

The drainage and filling system 31 fluidically connects the first low point A, the second low point B and the third low point C to an outlet 42 forming a general low point D located below points A, B and C. The system drainage and filling 31 is suitable for closing or opening points A, B and C.

The air bleeder-blocker 26 is located at a high point E of the path 20 between the sensor 34 and the turbine 36. The air bleeder-blocker 26 is adapted to allow gas to escape from the path 20 towards outside, and to admit a gas for example from the purge carriage 14.

The outlet 40 for example itself forms a high point F, which means that the hydrocarbon mixture 22 located between the outlet 40 and the valve 38 can exit via the low point C.

The high point F is for example located lower than the high point E.

As seen in Figures 1 and 3, the purge cart 14 comprises a frame 44, and wheels 46 mounted on the frame for rolling on a floor 48. In the example, the purge cart 14 includes three tanks 48A, 48B, 48C fixed to the frame 44 and adapted to respectively contain three qualities of hydrocarbon 50A, 50B, 50C distinct from each other and to respectively define three gaseous skies 52A, 52B, 52C above the hydrocarbon qualities.

The purge carriage 14 comprises a pressurization system 54 suitable for injecting a pressurized gas 56 selectively into any one of the gas overheads 52A, 52B, 52C. The purge carriage 14 comprises an exchange system 58 adapted to selectively drive any one of the hydrocarbon qualities 50A, 50B, 50C from one of the tanks 48A, 48B, 48C to the pilot meter 12 to fill the latter , and adapted to selectively receive in one of the tanks 48A, 48B, 48C any of the hydrocarbon qualities coming from the pilot meter 12 to purge the latter.

According to variants not shown, the purge carriage 14 comprises only two tanks, or more than three tanks, depending on the number of distinct qualities of hydrocarbon that it is desired to handle.

The hydrocarbon grades 50A, 50B, 50C are, for example, commonly used petroleum products, advantageously chosen from diesel, fuel oil and gasoline. Hydrocarbon grades 50A, 50B, 50C are liquid at a temperature of 25°C and an absolute pressure of 101325 Pa.

The frame 44 advantageously comprises two beams 60A, 60B extending in a longitudinal direction L, two crosspieces 62A, 62B extending between the two beams in a transverse direction T substantially perpendicular to the longitudinal direction L, and a gripping part 64 extending in particular in a vertical direction V. Advantageously, the frame 44 also includes a bottle holder 66.

According to variants not shown, the frame 44 may comprise more than two side members, or more than two crosspieces, or even have a more complex structure, for example stepped in the direction V.

The beams 60A, 60B are for example parallel to each other and perpendicular to the beams 60A, 60B. The beams 60A, 60B advantageously support an underside 67 of the tanks 408A, 48B, 48C.

The crosspieces 62A, 62B are for example located at the longitudinal ends of the longerons 60A, 60B.

The wheels 46 are for example four in number and advantageously located in the corners of the horizontal frame formed by the longitudinal members 60A, 60B and the crosspieces 62A, 62B.

The gripping part 64 is advantageously fixed to a longitudinal end of the beams 60A, 60B, and/or to the crosspiece 62B. Gripping portion 64 includes at least one upright 68 extending vertically, and at least one bar 70 adapted to be held by a user (not shown) of purge carriage 14.

The bar 70 is advantageously offset longitudinally with respect to the longitudinal ends of the side members 60A, 60B, so that the user does not have his feet in the wheels 46 or in the crosspiece 62B when holding the bar 70.

The bottle holder 66 is advantageously located longitudinally opposite the gripping part 64. The bottle holder 64 is for example fixed on the longitudinal end(s) of one and/or the other of the beams 60A, 60B , and/or on the crosspiece 62A. The bottle support 64 comprises for example a vertical upright 72, a bottom 74 fixed to the upright, and one or more strappings 76 also fixed to the upright.

The reservoirs 48A, 48B, 48C are advantageously aligned in the longitudinal direction L, each being accessible by the user from the same side of the purge carriage 14 in the transverse direction T.

Reservoirs 48A, 48B, 48C are advantageously similar to each other. Also only tank 48A will be described below.

The tank 48A has a capacity advantageously between 25 and 100 liters, preferably between 40 and 60 liters, and for example around 55 liters. By capacity, we mean here the maximum quantity of hydrocarbon mixture that the tank can contain in normal operation.

The tank 48A is for example of generally parallelepipedic shape. Besides the lower face 67, the tank 48A comprises an upper face 78 and two side faces 80, 82 transversely opposite. Tank 48A includes an inlet 84 and an outlet 86 for pressurized gas 56, and an outlet 88 for hydrocarbon grade 50A.

The tank 48A advantageously comprises a member 90 adapted to indicate the level of liquid formed by the quality of hydrocarbon 50A. Reservoir 48A advantageously also includes a second outlet 91 for the hydrocarbon grade 50A, and a safety valve 92 intended to prevent overpressure in reservoir 48A.

The inlet 84, the outlet 86 and the valve 92 are for example located on the upper face 78, to be in communication with the gas overhead 52A.

The member 90 is for example located on the side face 80. The member 90 comprises for example a tube 94 extending vertically and the ends of which are located respectively in the gas overhead 52A and in the hydrocarbon quality 50A. Tube 94 is intended to be partially filled with hydrocarbon grade 50A, to the same level as inside tank 48A.

The second outlet 91 is for example located at the bottom of the side face 80, and the outlet 88 is for example located on the lower face 67.

Outlet 86 and the second outlet 91 are respectively equipped with a shutter valve.

The pressurization system 54 comprises a bottle 96 containing the pressurized gas 56, the bottle resting on the bottom 74 of the bottle support 66, in the strapping or strappings 76.

The pressurization system 54 further comprises a pipe 98, a regulator 100 mounted on the bottle 96, a flexible pipe 102 fluidically connecting the pipe and the regulator, and three pipes 104A, 104B, 104C fluidically connecting the pipe 98 respectively to the inlets 84 for the pressurized gas, each of the pipes respectively comprising a shut-off valve 106A, 106B, 106C.

The pressurization system 54 is also suitable for venting any one of the tanks 48A, 48B, 48C using shut-off valves 108A, 108B, 108C fluidly connected to the outlets 86 of each of the tanks. respectively.

The pressurization system 54 is advantageously adapted to send the pressurized gas 56 to the pilot meter 12, for example thanks to a flexible pipe 110 connecting the pressure reducer 100 and the air purger-blocker 26.

According to a variant not shown, the air bleeder-blocker 26 is connected to another source of pressurized gas than the bottle 96.

The pressurized gas 56 comprises by volume at least 95%, preferably at least 99%, of nitrogen. Nitrogen is here an inert gas which has the merit of also inerting the tanks purged at the end of the sequence. According to a particular example, the pressurized gas 56 is nitrogen of cryogenic purity. The pressurized gas 56 is for example at a pressure of approximately 200 bars in the bottle 96 when the latter is put into service, this pressure decreasing gradually as the pressurized gas is consumed. In front of the regulator 100, the pressurized gas 56 is for example at a pressure of approximately 3 relative bars (i.e. in addition to atmospheric pressure).

The exchange system 58 comprises three pipes 112A, 112B, 112C, each of these pipes comprising a first end 114 respectively connected to one of the outlets 88, a second end 116 opposite the first end 114, and a valve of closure 118A, 118B, 118C located between the first end and the second end. The exchange system 58 comprises at least one flexible pipe 120 adapted to fluidically connect the second end 116 of any one of the pipes 112A, 112B, 112C and the pilot meter 12.

In the example shown, the flexible pipe 120 is advantageously connected to the general low point D formed by the outlet 42 of the drainage and filling system 31.

The operation of assembly 10 follows from its structure and will now be described. This operation illustrates a method according to the invention

The pilot meter 12 and the purge trolley 14 are brought to the site, for example using a van (not shown). They are unloaded and rolled to their place of use.

The path 20 of the pilot meter 12 is initially empty of any hydrocarbon quality and it is desired to pre-fill it with one of the hydrocarbon qualities 50A, 50B, 50C depending on the measuring system to be tested, for example the 50A hydrocarbon grade. For the other grades of hydrocarbons 50B and 50C, the operations would be similar and will not be described.

All shutter valves are initially closed.

The bottle 96 is connected to the pipe 98 by the flexible pipe 102 if it was not already done. The second end 116 of the pipe 112A is also connected to the general low point D of the pilot meter 12 by the flexible pipe 120.

Then, the regulator 100, the shut-off valve 106A, the shut-off valve 118A and the shut-off valves of the drainage and filling system 31 are opened.

Thanks to the pressurization system 54, pressurized gas 56 is injected into the gas overhead 52A. Pressure from overhead gas 52A presses hydrocarbon grade 50A in reservoir 48A and causes hydrocarbon grade 50A to flow through line 112A, flexible pipe 120, and drain and fill system 31. 20 thus gradually fills with 50A hydrocarbon quality. Gas present in the path 20 above the hydrocarbon quality 50A is evacuated via the air trap-blocker 26.

At least the drainage and filling system 31 is closed at the level of the low points A, B and C, and the air vent-blocker 26. The pilot meter 12 is then ready to be used to control or calibrate the whole of measurement.

At the end of these operations, the pilot meter 12 is purged of the hydrocarbon quality 50A, in order to be able to be used to test another measuring system (not shown) corresponding to a hydrocarbon quality distinct from the quality of hydrocarbon 50A. Hydrocarbon grade 50A is selectively received in tank 48A from pilot meter 12.

To do this, shut-off valve 106A is kept closed. The flexible hose 110 is installed to connect the regulator 100 to the air trap-blocker 26 in order to admit the pressurized gas 56 into the path 20 of the pilot meter 12 via the high point E.

Alternatively, flexible hose 102 is used to connect regulator 100 to air trap 26.

According to yet another variant, another source (not shown) of pressurized gas than the cylinder 96 is used to admit the pressurized gas 56 into the path 20 via the high point E.

It is ensured that the drainage and filling system 31 is open to allow an exit of the hydrocarbon quality 50A via the general low point D towards the purge trolley 14.

Shut-off valves 118A and 108A are open.

The pressurized gas 56 injected via the high point E pushes the hydrocarbon quality 50A present in the passage 20 to borrow the drainage and filling system 31, the flexible pipe 120, and the pipe 112A to arrive in the tank 48A. Part of the gas overhead 52A comes out going to the shutter valve 108A.

When the purge is complete, all the closing valves are closed and the flexible pipes 110 and 120 are disconnected.

According to a variant not shown, the air purger-blocker 26 is part of the accessories of the purge trolley 14 and is disconnected from the pilot meter 12 after the operations.

Thanks to the characteristics described above, the pilot meter 12 is easily pre-filled with any one of the three grades of hydrocarbon 50A, 50B, 50C depending on the intended use. Then, the pilot meter 12 is easily purged and the purged hydrocarbon quality is recovered in one of the tanks 48A, 48B, 48C dedicated to this quality. The calibration or control operations carried out using the pilot meter 12 are therefore simplified. This reduces their cost, without affecting the accuracy of the calibration, nor increasing the risk of mixing between the hydrocarbon qualities tested, and in compliance with the constraints related to the safety of people and installations.

Thanks to the optional alignment of the tanks 48A, 48B, 48C according to the longitudinal direction L, all the tanks are easily accessible. Thanks to the optional presence of the bottle support 66, the management of the pressurized gas 56 is facilitated.

Thanks to its advantageously narrow, simple and functional structure, the purge trolley 14 is easy to transport and to use.

Claims (10)

Purge cart (14) for allowing a pilot meter (12) to be purged and filled, the purge cart (14) comprising:
- a frame (44), and wheels (46) mounted on the frame (44) for rolling on a ground (48),
- a plurality of tanks (48A, 48B, 48C) fixed to the frame (44) and adapted to respectively contain a plurality of hydrocarbon qualities (50A, 50B, 50C) distinct from each other and liquid at a temperature of 25° C and a pressure of 101325 Pa, and to respectively define a plurality of gaseous skies (52A, 52B, 52C) above the hydrocarbon qualities (50A, 50B, 50C),
- a pressurization system (54) suitable for injecting a pressurized gas (56) selectively into any one of the gas overheads (52A, 52B, 52C), and
- an exchange system (58) adapted to selectively conduct any one of the hydrocarbon qualities (50A, 50B, 50C) from one of the tanks (48A, 48B, 48C) to the pilot meter (12) for filling the pilot meter (12), and adapted to selectively receive in one of the reservoirs (48A, 48B, 48C) any one of the hydrocarbon qualities (50A, 50B, 50C) coming from the pilot meter (12) to purge the pilot meter (12). A purge cart (14) according to claim 1, wherein the pressurization system (54) comprises at least one cylinder (96) containing the pressurized gas (56), the cylinder (96) resting on the frame (44). A purge cart (14) according to claim 2, wherein the pressurized gas (56) comprises by volume at least 95%, preferably at least 99%, nitrogen. A purge cart (14) as claimed in claim 2 or 3, wherein the reservoirs (48A, 48B, 48C) each have a plurality of inlets (84) for pressurized gas (56), the pressurization system (54) further comprising:
- a pipe (98),
- a regulator (100) mounted on the bottle (96),
- a flexible pipe (102) fluidically connecting the pipe (98) and the regulator (100), and
- a plurality of pipes (104A, 104B, 104C) fluidically connecting the pipe (98) respectively to the inlets for the pressurized gas (56), each of the pipes (104A, 104B, 104C) comprising a shut-off valve (106A, 106B, 106C). A purge cart (14) according to any of claims 2 to 4, wherein the pressurization system (54) is further adapted to:
- vent any of the tanks (48A, 48B, 48C), and/or
- To send the pressurized gas (56) to the pilot meter (12). Purge cart (14) according to any one of claims 1 to 5, wherein the reservoirs (48A, 48B, 48C) respectively comprise outlets (88) for the hydrocarbon grades (50A, 50B, 50C), the exchange system (58) comprising:
- a plurality of pipes (112A, 112B, 112C), each of the pipes (112A, 112B, 112C) comprising a first end (114) respectively connected to one of the outlets (88), a second end (116) opposite the first end (114), and a gate valve (118A, 118B, 118C) located between the first end (114) and the second end (116), and
- at least one flexible pipe (120) adapted to fluidically connect the second end (116) of any one of the pipes (112A, 112B, 112C) and the pilot meter (12). A purge cart (14) as claimed in any one of claims 1 to 6, wherein the reservoirs (48A, 48B, 48C) have a capacity of between 25 and 100 litres. A purge cart (14) as claimed in any one of claims 1 to 7, wherein each of the reservoirs (48A, 48B, 48C) includes a member (90) adapted to indicate a level of liquid in said reservoir (48A, 48B, 48C). An assembly (10) comprising a pilot meter (12) and a purge cart (14) according to any one of claims 1 to 8 for purging and filling the pilot meter (12). Method implementing an assembly (10) according to claim 9, and comprising the following steps:
- injection by the pressurization system (54) of the pressurized gas (56) selectively in any one of the gas overheads (52A, 52B, 52C),
- filling of the pilot meter (12) selectively with one of the hydrocarbon qualities (50A, 50B, 50C) via the exchange system (58),
- selective reception in one of the tanks (48A, 48B, 48C) of any one of the hydrocarbon qualities (50A, 50B, 50C) coming from the pilot meter (12), and
- purge of the pilot meter (12).