IES20000293A2 - An apparatus and a method for determining vapour transfer parameters in a liquid transfer operation - Google Patents
An apparatus and a method for determining vapour transfer parameters in a liquid transfer operationInfo
- Publication number
- IES20000293A2 IES20000293A2 IES20000293A IES20000293A2 IE S20000293 A2 IES20000293 A2 IE S20000293A2 IE S20000293 A IES20000293 A IE S20000293A IE S20000293 A2 IES20000293 A2 IE S20000293A2
- Authority
- IE
- Ireland
- Prior art keywords
- vapour
- storage tank
- supply tank
- pressure
- tank
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B67—OPENING, CLOSING OR CLEANING BOTTLES, JARS OR SIMILAR CONTAINERS; LIQUID HANDLING
- B67D—DISPENSING, DELIVERING OR TRANSFERRING LIQUIDS, NOT OTHERWISE PROVIDED FOR
- B67D7/00—Apparatus or devices for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers, e.g. for retail sale purposes
- B67D7/04—Apparatus or devices for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers, e.g. for retail sale purposes for transferring fuels, lubricants or mixed fuels and lubricants
- B67D7/0476—Vapour recovery systems
- B67D7/0496—Performance test devices therefor
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Loading And Unloading Of Fuel Tanks Or Ships (AREA)
Abstract
A apparatus (1) for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank (4) to an underground tank (5) is positioned in-line therebetween. The apparatus (1) is positioned between a vapour recovery system (7,8,30) of the storage tank (5) and a vapour recovery system dedicated connection (10) of the supply tank (4) and facilitates the monitoring of the vacuum created in the supply tank (4) during liquid transfer and the pressure generated in the storage tank (5). The apparatus (1) has a ground engaging plate (17), which supports a communicating pipe (20) having an inlet port (18) and an outlet port (19), attached to the storage tank (5) and the supply tank (4), respectively, which can be isolated from each other by means of a full bore ball valve (21). The apparatus (1) also has pressure-monitoring means (25,26) associated with the inlet port (18) and the outlet port (19), respectively. The apparatus (1) is used to test various parameters of the vapour recovery system. Also, during normal liquid delivery, by monitoring of the vacuum developed in the supply tank (4) and determining that it is close to the maximum permitted vacuum, it can be concluded that adequate vapour recovery is occurring. <Figure 4>
Description
The present invention relates to an apparatus and a method for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank to a storage tank for facilitating adequate transfer of vapour from the storage tank to the supply tank, and in particular, though not limited the invention relates to a method and apparatus for determining fuel vapour transfer parameters in a liquid fuel transfer operation from a tanker, typically, a road tanker to a storage tank, typically, a storage tank located under ground.
In the transfer of liquid fuel, for example, petrol which is a highly volatile liquid, from a road tanker to a storage tank, it is essential that vapour generated in the storage tank as the storage tank is being filled is transferred to the tanker as the level of liquid fuel falls in the tanker. Otherwise, such vapours are exhausted to atmosphere with consequent environmental damage, breaching environmental protection regulations, and more seriously, the risk of fire and/or explosion.
Underground fuel storage tanks, in general, are provided with a venting system for venting the storage tank to atmosphere in the event of a build up of pressure or an excessive vacuum developing in the storage tank. Typically, an upstanding pipe extends upwardly from the storage tank and terminates in a pressure and vacuum release valve mechanism for relieving over pressure and a vacuum build up in the underground storage tank. In the case of underground fuel tanks such as petrol tanks, and tanks for storing other relatively highly volatile liquids a vapour recovery
IE000293 connection is provided on the upstanding pipe for connecting to a dedicated vapour recovery connection of a road tanker so that vapour displaced from the underground storage tank during filling of the underground storage tank from the road tanker can be transferred from the underground storage tank to the road tanker. In many cases, particularly, in the case of underground petrol storage tanks many storage tanks may be provided underground adjacent each other, and typically, an upstanding pipe extends from each underground tank, and the upstanding pipes terminate in a common manifold on which the pressure and vacuum relief valve mechanism is located. The vapour recovery connection for connecting the underground storage tanks to the vapour recovery connection of the road tanker is typically provided on the manifold. The construction and arrangement of such underground storage tanks, their pressure and vacuum relief valving mechanism and the provision of a vapour outlet connection for facilitating transfer of displaced vapour from the underground tanks to the road tanker will be well known to those skilled in the art.
In order to ensure a full recovery of displaced vapour from the underground storage tank to the road tanker, it is essential that a pressure differential exist in the vapour space above fuel in the underground storage tank, and in the vapour space above the fuel in the road tanker during delivery of fuel from the road tanker to the underground storage tank or tanks. Typically, where a single hose fuel delivery is being carried out from a road tanker to an underground storage tank the vapour pressure differential between the underground storage tank and the road tanker should be approximately 5mBar. In a two hose fuel delivery system the vapour pressure differential should be approximately 10mBar. For a three hose delivery the vapour pressure differential should be approximately 15mBar, and ideally, a vapour
IE000293 pressure differential of 20mBar should be developed when four hoses are delivering fuel from the road tanker to the underground storage tanks.
As well as a pressure and vacuum relief mechanism being provided for the underground storage tanks, a vacuum relief valve is also provided on the road tanker. Typically, the pressure and vacuum relief valve mechanism on the storage tanks is set to blow at a maximum pressure of approximately 35mBar. The vacuum relief valve on the road tanker typically is set to blow at a maximum vacuum of approximately 20mBar. Accordingly, to ensure adequate vapour transfer between the underground storage tank or tanks and the road tanker, it is essential that the pressure vacuum relief valve mechanism of the underground storage tank or tanks and the vacuum relief valve of the tanker should not trip until these respective values have been reached. Otherwise, there may be insufficient pressure differential for driving the vapour from the storage tank to the road tanker.
There is therefore a need for a method and apparatus for determining vapour transfer parameters, in particular, pressures in a liquid transfer operation in which a volatile liquid is being transfer from a supply tank to a storage tank for facilitating transfer of vapour from the storage tank to the supply tank.
The present invention is directed towards providing such a method and apparatus.
According to the invention there is provided apparatus for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank to a storage tank for facilitating adequate transfer of
IE000293 vapour from the storage tank to the supply tank, the apparatus comprising an inlet port for connecting to a vapour recovery system of the storage tank, an outlet port for connecting to a vapour recovery system of the supply tank, communicating means communicating the inlet port with the outlet port, an isolating means in the communicating means for selectively isolating the inlet port and the outlet port from each other, a monitoring means for measuring pressure between the isolating means and the respective ports when the isolating means is closed for determining the pressure in the vapour recovery system of the storage tank and for determining the vacuum in the vapour recovery system of the supply tank.
to
In one embodiment of the invention a pair of connecting means is provided for receiving the monitoring means between the isolating means and the respective inlet and outlet ports.
In one embodiment of the invention the apparatus is for determining the vapour transfer parameters in connection with fuel vapour, and in particular, in connection with a liquid fuel transfer operation in which liquid fuel is transferred from a tanker to a storage tank, and in particular, though not limited to the transfer of liquid fuel from a road tanker to an underground storage tank.
The invention also provides a method for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank to a storage tank for facilitating adequate transfer of vapour from the storage tank to the supply tank, the method comprising the step of connecting the apparatus between a vapour recovery return system of the storage tank and a vapour recovery
IE000293 system of the supply tank with the inlet port of the apparatus being connected to the vapour recovery return system of the storage tank, and the outlet port being connected to the vapour recovery system of the supply tank, isolating the inlet port from the outlet port delivering fuel from the supply tank to the storage tank monitoring the vacuum build up in the supply tank by monitoring the pressure on the supply tank side of the isolating means and determining the pressure at which the vacuum relief valve of the vapour recovery system of the supply tank trips, monitoring the pressure on the storage tank side of the isolating means and determining the pressure at which the pressure relief valve of the vapour recovery return system of the storage tank trips.
In one embodiment of the invention the method further comprises interrupting delivery of the liquid from the supply tank to the storage tank after the vacuum relief valve has tripped and after the pressure relief valve has tripped, and monitoring the respective vacuum and pressure for determining the time period during which the respective vacuum and pressure in the supply tank and the storage tank hold for determining if there is a leak in either of the systems, and preferable the extent of such leakage.
The invention further provides a method for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank to a storage tank for facilitating adequate transfer of vapour from the storage tank to the supply tank, the method comprising the step of connecting the apparatus between a vapour recovery return system of the storage tank, and a vapour recovery system of the supply tank with the inlet port of the apparatus being
IE000293 connected to the vapour recovery return system of the storage tank and the outlet port being connected to the vapour recovery system of the supply tank, and monitoring the vapour pressure of the vapour being transferred through the apparatus for determining the vacuum level in the supply tank.
Advantageously, the apparatus is located relatively closely to the supply tank, and preferably, a connecting hose connecting the apparatus to the vapour recovery system of the supply tank does not exceed 1 .OM.
In one embodiment of the invention the supply tank is a tanker, and typically, road tanker and the storage tank typically, is an underground storage tank, and in a further embodiment of the invention the liquid being transferred is a volatile liquid fuel, for example, petrol or like.
The invention will be more clearly understood from the following description of an embodiment thereof which is given by way of example only with reference to the accompanying drawings in which:
Fig. 1 is a front elevationai view of apparatus according to the invention for determining vapour transfer parameters in a liquid transfer operation between a supply tank and a storage tank,
Fig. 2 is a plan view of the apparatus of Fig. 1,
Fig. 3 is a diagrammatic elevationai view of the apparatus of Fig 1, and
IE000293
Fig. 4 is a schematic diagram of the apparatus of Fig. 1, in use.
Referring to the drawings there is illustrated apparatus according to the invention indicated generally by the reference numeral 1 for determining vapour transfer parameters, in other words, pressure in a liquid transfer operation in which a volatile liquid, namely, liquid fuel, such as petrol is being transferred from the supply tank, namely, a road tanker 4 to a underground storage tank 5. The storage tank 5 is fitted with a vapour recovery return line 7 through which vapour generated in the storage tank 5 is returned to the road tanker 4. The vapour recovery return line 7 extends above the ground and is fitted with a pressure and vacuum relief valve 8 for venting vapour to atmosphere in the event of an excessive build up of vapour pressure or a vacuum in the storage tank 5. Typically, the pressure relief valve 8 is set to trip at a vapour pressure of approximately 35mBar. The tanker 4 is fitted with a vapour recovery system which receives vapour from the vapour recovery return line 7 during delivery of fuel from the tanker 4 to the storage tank 5. A dedicated connection 10 located externally of the tanker 4 is provided for receiving the vapour from the vapour recovery return line 7. The vapour recovery system of the tanker 4 operates under a vacuum as fuel is being delivered from the tanker 4 to the storage tank 5 for drawing vapour from the storage tank 5 to the tanker 4, and a vacuum relief valve 9 of the vapour recovery system prevents excessive build up of vacuum in the road tanker 4. In a normal delivery of fuel from the tanker 4 to the storage tank 5 the fuel outlet from the tanker 4 is connected to a fuel inlet to the storage tank 5 neither of which are illustrated by a hose (not shown). A hose also not shown in
Figs. 1 to 3 connects the vapour recovery return line 7 to the dedicated connection
IE000293 for returning vapour from the storage tank 5 to the tanker 4. This aspect of delivering of fuel from a tanker 4 to a storage tank 5 will be well known to those skilled in the art.
The apparatus 1 according to the invention comprises a ground engaging base plate 17 for supporting the apparatus 1 on the ground. An upstanding support member 15 extends upwardly from the base plate 17 for supporting a communicating means, namely, a communicating pipe 20 for communicating an inlet port 18 and an outlet port 19 extending from the lower and upper ends, respectively, of the communicating pipe 20. The inlet port 18 is provided for connecting the apparatus 1 to the vapour recovery return line 7 of the storage tank 5, and the outlet port 19 is provided for connecting the apparatus 1 to the vapour recovery connection 10 of the road tanker 4 so that the vapour recovery return line 7 is connected to the vapour recovery connection 10 through the apparatus 1. The diameter of the communicating pipe 20 and the inlet and outlet ports 18 and 19 is substantially similar to the diameter of the pipework of the vapour recovery system used for connecting between the vapour recovery system of the tanker 4 and the storage tank 5. The communicating pipe 20 is closed at its upper end by a top closure plate 16. A 90° elbow 14 at the lower end of the communicating pipe 20 directs the inlet port 18 in the opposite direction to that of the outlet port 19.
An isolating means for isolating the outlet port 19 from the inlet port 18 comprises a full bore ball valve 21 which is located in the communicating pipe 20 intermediate the inlet port 18 and the outlet port 19. A pair of connecting means provided by connecting ports 23 and 24 are provided on opposite sides of the isolating valve 21,
IE000293 and between the isolating valve 21 and the inlet and outlet ports 18 and 19, respectively, for receiving manometers 25 and 26, respectively for determining the pressure in the vapour recovery return line 7 and of the vacuum in the vapour recovery system of the tanker 4 as will be described below.
Valves 35 and 36 are provided between the manometers 25 and 26, respectively for isolating the connecting ports 23 and 24, respectively from the communicating pipe 20 in the event that only one manometer is provided, and the manometer has to be moved between the connecting ports 23 and 24.
io
A safety relief valve 27 located in the top closure plate 16 vents the communicating pipe 20 in the event of an excessive pressure or vacuum build up in the apparatus 1.
An additional connecting port 28 communicating with the communicating pipe 20 15 extends from the communicating pipe 20 above the elbow 14 for releasably receiving a differential pressure flowmeter (not shown) for facilitating pressure based flow measurements. Needless to say, the additional port 28 could receive other types of meters for making other types of measurements. A valve (not shown) is provided in the connecting port 28 for selectively opening and closing the port 28.
A venturi assisted by-pass 22 allows for forced evacuation from the communicating pipe 20 in either direction when the isolating valve 21 is closed. Valves 31 and 32 connect the venturi by-pass 22 into the communicating pipe 20 on respective opposite sides of the isolating valve 21.
IE000293 ίο
In use, the apparatus 1 is connected to the road tanker 4 and to the storage tank 5. The outlet port 19 is connected by a hose 29 to the dedicated connection 10 of the vapour recovery system of the tanker 4. The hose 29 should be relatively short to ensure minimum distance between the outlet port 19 and the dedicated connection
, typically the hose 29 should not exceed 1.0M. The inlet port 18 is connected to the vapour recovery return line 7 of the storage tank 5 by a hose 30, and the apparatus so connected is ready for operation.
Initially, the apparatus 1 monitors the vacuum in the road tanker 4. This is carried out by closing the isolating valve 21 so that the inlet and outlet ports 18 and 19 are isolated from each other. Fuel is delivered from the road tanker 4 to the storage tank and the vacuum drawn in the tanker 4 is monitored on the manometer 26. The vacuum drawn in the tanker 4 is monitored until the vacuum relief valve 9 of the tanker 4 trips, and the vacuum at which the vacuum relief valve 9 trips is recorded.
Provided the vacuum relief valve trips at a vacuum of approximately 20mBars, the vacuum drawn by the tanker 4 should be acceptable for drawing vapour from the storage tank 5 to the tanker 4. The pressure developed in the storage tank 5 is then monitored, or indeed, may be simultaneously monitored with the monitoring of the vacuum drawn in the tanker 4 by reading the manometer 25 until the pressure relief valve of the pressure vacuum relief valve 8 trips. The pressure at which the pressure relief valve 8 trips is recorded, and provided the pressure relief valve 8 does not trip before a pressure of approximately 35mBars the pressure in the storage tank 5 is adequate for driving the vapour from the storage tank 5 to the tanker 4. Accordingly, providing the vacuum drawn by the tanker 4 is approximately
20mBars, and the pressure in the storage tank 5 is approximately 35mBars, an
IE000293 adequate vapour pressure differential can be developed for driving the vapour from the storage tank 5 to the tanker 4.
A test for leakage in the vapour recovery system of the storage tank 5 and the vapour recovery system of the road tanker 4 may also be carried out using the apparatus 1. This test is carried out by closing the isolating valve 21 and commencing delivery from the tanker 4 into the storage tank 5 until the pressure relief valve 8 trips. At which stage delivery of fuel from the tanker 4 to the storage tank 5 is interrupted and the pressure recorded on the manometer 25 is monitored for a predetermined period of time to determine if the pressure in the storage tank 5 and the vapour recovery return line 7 holds. If the pressure recorded by the manometer 25 holds, then the storage tank 5 and the vapour recovery return line 7 of the storage tank 5 is free of leaks. Otherwise, a leak exists. A similar test may be carried out for determining leaks on the vacuum side of the apparatus 1. This test is carried out in similar fashion with the exception that the vacuum is read on the manometer 26.
After carrying out of the tests the isolating valve 21 is open and delivery of the fuel from the road tanker 4 to the storage tank 5 continues. During delivery of the fuel vapour is driven from the storage tank 5 to the road tanker 4 through the apparatus 1. While delivery of petrol from the road tanker 4 to the storage tank 5 continues the vapour pressure on the manometer 25 can be periodically read for determining the vacuum in the road tanker 4 for ensuring that the vacuum is maintained during delivery. Since as discussed above the hose 29 connecting the outlet port 19 from the apparatus 1 to the dedicated connection 10 of the vapour recovery system of the
IE000293 tanker 4 is relatively short the vacuum read on the manometer during delivery of petrol from the road tanker 4 to the storage tank 5 gives a close approximation of the vacuum being drawn in the road tanker 4.
The invention is not limited to the embodiment herein before described which may be varied in construction and detail.
Claims (5)
1. Claims: 1. Apparatus for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank to a storage tank for facilitating adequate transfer of 5 vapour from the storage tank to the supply tank, the apparatus comprising an inlet port for connecting to a vapour recovery system of the storage tank, an outlet port for connecting to a vapour recovery system of the supply tank, communicating means communicating the inlet port with the outlet port, an isolating means in the communicating 10 means for selectively isolating the inlet port and the outlet port from each other, a monitoring means for measuring pressure between the isolating means and the respective ports when the isolating means is closed for determining the pressure in the vapour recovery system of the storage tank and for determining the vacuum in the vapour recovery 15 system of the supply tank.
2. A method for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank to a storage tank for facilitating adequate transfer of vapour from the storage tank to the supply tank, the method comprising 20 the steps of connecting an apparatus having an inlet port and an outlet port between a vapour recovery return system of the storage tank and a vapour recovery system of the supply tank, the inlet port of the apparatus being connected to the vapour recovery return system of the storage tank, and the outlet port being connected to the vapour recovery system 25 of the supply tank, and communicating means communicating the inlet IE000293 port with the outlet port, closing an isolating means to isolate the inlet port from the outlet port, delivering fuel from the supply tank to the storage tank, monitoring the vacuum build up in the supply tank by monitoring the pressure on the supply tank side of the isolating means 5 and determining the pressure at which the vacuum relief valve of the vapour recovery system of the supply tank trips, monitoring the pressure on the storage tank side of the isolating means and determining the pressure at which the pressure relief valve of the vapour recovery return system of the storage tank trips. 10
3. A method according to Claim 2, which comprises interrupting delivery of the liquid from the supply tank to the storage tank after the vacuum relief valve has tripped and after the pressure relief valve has tripped, waiting for the vacuum relief valve and the pressure relief valve to reset, and monitoring the respective vacuum and pressure 15 for a time period of between thirty and ninety seconds to determine if there is a leak in either of the systems.
4. A method for determining vapour transfer parameters in a liquid transfer operation in which a volatile liquid is being transferred from a supply tank to a storage tank for facilitating adequate transfer of 20 vapour from the storage tank to the supply tank, the method comprising the steps of connecting an apparatus having an inlet port and an outlet port between a vapour recovery return system of the storage tank, and a vapour recovery system of the supply tank with the inlet port of the apparatus being connected to the vapour recovery return system of the 25 storage tank and the outlet port being connected to the vapour recovery IE000293 15 system of the supply tank, and communicating means communicating the inlet port with the outlet port, monitoring the vapour pressure of the vapour being transferred through the apparatus, and measuring the vacuum generated in the supply tank to confirm effective vapour 5. Balancing between the storage tank and the supply tank during liquid transfer.
5. Apparatus according to Claim 1, substantially as hereinbefore described with particular reference to and as illustrated in the accompanying drawings.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IES20000293 IES20000293A2 (en) | 2000-04-20 | 2000-04-20 | An apparatus and a method for determining vapour transfer parameters in a liquid transfer operation |
| AU2001248720A AU2001248720A1 (en) | 2000-04-20 | 2001-04-19 | An apparatus and methods for determining vapour transfer parameters in a liquid transfer operation |
| PCT/IE2001/000051 WO2001081237A1 (en) | 2000-04-20 | 2001-04-19 | An apparatus and methods for determining vapour transfer parameters in a liquid transfer operation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IES20000293 IES20000293A2 (en) | 2000-04-20 | 2000-04-20 | An apparatus and a method for determining vapour transfer parameters in a liquid transfer operation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| IES20000293A2 true IES20000293A2 (en) | 2001-11-14 |
Family
ID=11042598
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| IES20000293 IES20000293A2 (en) | 2000-04-20 | 2000-04-20 | An apparatus and a method for determining vapour transfer parameters in a liquid transfer operation |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU2001248720A1 (en) |
| IE (1) | IES20000293A2 (en) |
| WO (1) | WO2001081237A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE602005014180D1 (en) * | 2004-08-24 | 2009-06-10 | Michael O'kane | Apparatus and method for testing vapor recovery systems |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5450883A (en) * | 1994-02-07 | 1995-09-19 | Gilbarco, Inc. | System and method for testing for error conditions in a fuel vapor recovery system |
| US6038929A (en) * | 1998-11-19 | 2000-03-21 | Dresser Industries, Inc. | Three-way valved apparatus and method for testing pressure in a fluid system |
-
2000
- 2000-04-20 IE IES20000293 patent/IES20000293A2/en not_active IP Right Cessation
-
2001
- 2001-04-19 WO PCT/IE2001/000051 patent/WO2001081237A1/en not_active Ceased
- 2001-04-19 AU AU2001248720A patent/AU2001248720A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| WO2001081237A1 (en) | 2001-11-01 |
| AU2001248720A1 (en) | 2001-11-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MK9A | Patent expired |