GB2481015A

GB2481015A - Exhaust emissions sampling system

Info

Publication number: GB2481015A
Application number: GB201009528A
Authority: GB
Inventors: Ken Turnball; Alan Lowther; Steve Houseman
Original assignee: MARTEK MARINE Ltd
Current assignee: MARTEK MARINE Ltd
Priority date: 2010-06-08
Filing date: 2010-06-08
Publication date: 2011-12-14
Anticipated expiration: 2030-06-08
Also published as: GB201009528D0; GB2481015B

Abstract

The device 10, (92), (94), (96), (98) and a system (90) samples exhaust emissions 14 in an exhaust duct 12. The device comprises a body 18 and a sampling member 16. The body has a first chamber 30. The sampling member 16 for location in the exhaust duct 12 and for providing fluid communication between the exhaust duct 12 and the first chamber 30. The device 10, (92), (94), (96), (98) further includes a heat conduction member 34 between the sampling member 16 and the first chamber 30 for conducting heat from the exhaust emissions 14 within the exhaust duct 12 to the first chamber 30. The heat conduction member may be a sintered metal filter. The system 90 separately claimed comprises a plurality of devices 10 wherein each first chamber has an outlet port with a valve which can be made to connect one of a plurality of first chambers with a sample duct 84.

Description

Improvements in the Samplinu of Exhaust Emissions

Technical Field

The invention relates to improvements in the sampling of exhaust emissions, and in particular the sampling of exhaust emissions of ships.

Background

Large ocean going ships such as container ships, tanker vessels or cruise ships are typically powered by one or more large engines which are fuelled by Marine Diesel Oil.

Exhaust emissions from such ships may be required to comply with environmental legislation and in certain geographical zones, such as Sea Environmental Coast Areas (SECA), low-sulphur Marine Diesel Oil must be used. Furthermore, in such SECA zones an operator of a ship may be required to prove to marine authorities that the exhaust emissions comply with regulations for levels of carbon oxides (COx), sulphur oxides (SOx), nitrogen oxides (NOx), and other exhaust emissions.

th addition to compliance with regulations for the exhaust emissions, the ship operator may also wish to monitor the exhaust emissions when performing engine optimisation adjustments to improve friel efficiency. Typically such large ships require a large amount of ftiel and even small percentage improvement in engine operating efficiency can provide large cost savings for fuel. Such engine optimisation may include changing the operational parameters of the engine, and monitoring the exhaust emissions in response to the changed operational parameters.

It is known to provide a device for sampling exhaust emissions in an exhaust duct of a ship. The device comprises an intake duct connected to a housing. The housing is mounted on an exterior of the exhaust duct and the intake duct is located inside the exhaust duct. The intake duct collects the exhaust emissions from the exhaust duct and passes them to the housing of the device. Once the exhaust emissions have been collected by the device they are passed to a gas analyser to determine their content. The exhaust emissions typically have a high moisture content and when sampling and analysing is being performed the exhaust emissions are required to be maintained above their dew point to avoid or minimise condensation developing in the device or the gas analyser. Typically the exhaust emissions can be maintained above the dew point by maintaining them above a temperature of about 15 0°C. If the temperature falls below about 150°C then condensation may form and a part of the exhaust emissions may dissolve in the condensation which may cause the gas analyser to provide a false reading.

The known device for sampling exhaust emissions uses an electric heating element for the housing which maintains the exhaust emissions at the required temperature. Such an arrangement has the problem that the device requires electricity to power the electric heating element. A further problem is that the electric heating element is required to be controlled to maintain the temperature of the housing above the dew point, which requires a control cable connected to a central control unit. These problems are compounded where there are multiple exhaust ducts on the ship and where each exhaust duct has its own device for sampling the exhaust emissions. Overall the use of electric heating elements increases the complexity, the cost of installation, and the cost of operation of the device for sampling exhaust emissions.

It is further known to couple a plurality of devices for sampling exhaust emissions from a plurality of exhaust ducts to a single gas analyser via a separate manifold. Such an arrangement avoids the need for more than one gas analyser, and is achieved by providing a sample duct between each device and the manifold. For example, if there are four devices for sampling exhaust emissions then four separate sample ducts must be used between each device and the manifold. A further sample duct is then used between the manifold and the gas analyser. A plurality of valves at the manifold are then selectively activated to deliver the exhaust emissions from a particular exhaust duct to the gas analyser. With such an arrangement the manifold and the sample ducts are required to be heated so that the exhaust emissions are maintained above their dew point. Such an arrangement has the disadvantage that a large amount of heated sample duct is required to deliver the exhaust emissions to the manifold, and from the manifold to the gas analyser. Furthermore the separate manifold is required to be heated to maintain the exhaust emissions above their dew point. Such a large amount of heated sample duct and the heated manifold increases the costs and complexity for installation and operation when using a plurality of devices for sampling exhaust emissions from a plurality of exhaust ducts.

It is broadly an object of the present invention to address one or more of the above mentioned disadvantages of the previously known ways for sampling exhaust emissions.

Summary

What is required is a way of readily permitting exhaust emissions to be maintained at a required temperature and/or reducing the length of sample duct required, which may reduce or minimise at least some of the above-mentioned problems.

According to a first aspect of the invention, there is provided a device for sampling exhaust emissions in an exhaust duct, comprising a body and a sampling member, the body having a first chamber, the sampling member for location in the exhaust duct and for providing fluid communication between the exhaust duct and the first chamber, wherein the device further includes a heat conduction member between the sampling member and the first chamber for conducting heat from the exhaust emissions within the exhaust duct to the first chamber.

Such a device provides the advantage that the high temperature of the exhaust emissions is used to supply the required heat energy to maintain the exhaust emissions above the dew point so that the formation of condensation is avoided or reduced. Since the exhaust emissions are typically above 150°C, and usually at about 300°C under normal operating conditions, the heat of combustion in the exhaust emissions can be used to maintain the exhaust emissions in the device above the dew point. The device does not require electricity to power an electric heating element which reduces complexity.

These advantages are even more significant where there are multiple exhaust ducts on the ship and where each exhaust duct requires its own device for sampling the exhaust emissions. Overall the device may reduce the complexity, the cost of installation, and the cost of operation when compared to the prior art. Furthermore, such a device may provide for a more reliable way of sampling exhaust emissions due to the elimination of the electric heating element.

Preferably the heat conduction member comprises a first filter. Preferably the heat conduction member comprises a sintered metal member. Such a filter provides the advantage of being able to at least partially remove soot from the exhaust emissions.

The heat conduction member provides the combined advantage of being able to filter the exhaust emissions and conduct heat into the first chamber.

In one embodiment the sampling member comprises the heat conduction member.

Preferably the first chamber further includes a second filter. Preferably the second filter defines a second chamber. Such a second filter is after the first filter and operates to further remove soot from the exhaust emissions.

Preferably the second chamber is within the first chamber. Preferably the second chamber has a first closable aperture through which the heat conduction member can be removed. The first closable aperture further provides the advantage of allowing soot to be cleaned from the second chamber.

Preferably the body has a second closable aperture through which the heat conduction member can be removed. The second closable aperture further provides the advantage of allowing soot to be cleaned from the first chamber.

Preferably the second filter is removable via the second closable aperture.

The body may have a tapered collar for attachment to the exhaust duct. Such a tapered collar may reduce unwanted heat conduction away from the body.

Preferably the first chamber has an outlet port. Preferably the outlet port has a valve which can be selectively opened and closed to place the first chamber in fluid communication with a sample duct. Such an arrangement has the advantage that the valve can be operated to sample the exhaust emissions from the exhaust duct.

Preferably the valve is adjacent to the body. Such an arrangement means that the distance between the valve and the body is small which provides the advantage that exhaust emissions are passed directly to a sample duct when the valve is in the open position.

Preferably at least a part of the heat conduction member is within the first chamber.

Preferably at least a part of the heat conduction member is within the sampling member.

Such arrangements provide the advantage of an improved conduction of heat from the sampling member to the first chamber.

In a preferred arrangement the part of the heat conduction member within the sampling member has a larger thermal capacity than the part of the heat conduction member within the first chamber.

Preferably the part of the heat conduction member within the first chamber is between -20 % of the length of the part of the heat conduction member within the sampling member.

According to a second aspect of the invention there is provided a method of sampling exhaust emissions in an exhaust duct using a device comprising a sampling member and a body having a first chamber, the sampling member for location in the exhaust duct and for providing fluid communication between the exhaust duct and the first chamber, the method including: drawing the exhaust emissions from the exhaust duct into the first chamber via the sampling member; and transferring heat energy from the exhaust emissions within the exhaust duct to heat the first chamber.

Such a method of sampling provides the advantage that the high temperature of the exhaust emissions is used to supply the required heat energy to maintain the exhaust emissions above the dew point so that the formation of condensation is avoided or reduced. Since the exhaust emissions are typically above 150°C, and usually at about 300°C under normal operating conditions, the heat of combustions in the exhaust emissions can be used to maintain the exhaust emissions in the device above the dew point. The method does not require electricity to power an electric heating element of the prior art which reduces complexity. With the method according to the invention these advantages are even more significant where there are multiple exhaust ducts on the ship and where each exhaust duct requires its own device for sampling the exhaust emissions. Overall the method may reduce the complexity, the cost of installation, and the cost of operation when compared to the prior art. Furthermore, such a method may provide for a more reliable way of sampling exhaust emissions due to the elimination of the electric heating element.

Preferably the method further includes transferring the heat energy using a heat conduction member for conducting heat from the exhaust emissions within the exhaust duct to the first chamber. Such a heat conduction member provides a direct and efficient way of transferring the heat energy to the required part of the device.

Preferably the method further includes filtering the exhaust emissions from the exhaust duct. Such filtering provides the advantage of being able to at least partially remove soot from the exhaust emissions.

Preferably the method further includes performing said filtering using the heat conduction member. Using the heat conduction member in this way provides the combined advantage of being able to filter the exhaust emissions and conduct heat into the first chamber.

Preferably the method further includes insulating the body from the exhaust duct. Such insulating may assist with reducing unwanted heat conduction away from the body.

Preferably the method further includes including transferring the exhaust emissions from the first chamber to a sample duct via a valve which is adjacent to the body. Such transferring has the advantage that the valve can be operated to sample exhaust emissions from the exhaust duct and passed to the sample duct. Furthermore such transferring means that the distance between the valve and the body is small which provides the advantage that exhaust emissions are passed directly to the sample duct when the valve is in the open position.

Preferably the method further includes using the heat conduction member with at least a part thereof within the first chamber or the sampling member. Such a method provides the advantage of an improved conduction of heat from the sampling member to the first chamber.

Preferably the method further includes using the heat conduction member such that the part thereof within the sampling member has a larger thermal capacity than the part thereof within the first chamber.

According to a third aspect of the invention there is provided a sampling system comprising a plurality of devices for selectively sampling exhaust emissions from one of a plurality of exhaust ducts, each device comprising a body and a sampling member, each body having a first chamber, each sampling member for location in a respective exhaust duct and for providing fluid communication between the respective exhaust duct and the respective first chamber, wherein each first chamber has an outlet port with a valve which can be selectively opened and closed to place one of said first chambers in fluid communication with a sample duct.

Such a sampling system provides the advantage that one of the valves can be selectively operated to transfer the exhaust emissions from a particular exhaust duct into the single sample duct. This may help to reduce the length of the sample duct leading to a gas analyser. These advantages are even more significant where there are many exhaust ducts on the ship and where each exhaust duct requires its own device for sampling the exhaust emissions. Overall the sampling system may reduce the complexity, the cost of installation, and the cost of operation when compared to the prior art.

Preferably each valve is adjacent to each body of the plurality of devices. Such an arrangement means that the distance between the valve and the body is small which provides the advantage that exhaust emissions are passed directly to the sample duct when one of the valves is in the open position.

Preferably each device further includes a heat conduction member between each sampling member and each first chamber for conducting heat from the exhaust emissions from one of the exhaust ducts to each first chamber. Such an arrangement has the advantage that the high temperature of the exhaust emissions is used to supply the required heat energy to maintain the exhaust emissions above the dew point so that the formation of condensation is avoided or reduced. The devices do not require electricity to power electric heating elements according to the prior art, which reduces complexity.

Preferably each heat conduction member comprises a first filter. Preferably each heat conduction member comprises a sintered metal member. Such a filter provides the advantage of being able to at least partially remove soot from the exhaust emissions.

In one embodiment each sampling member comprises the heat conduction member.

Preferably at least a part of each heat conduction member is within each first chamber.

Preferably at least a part of each heat conduction member is within each sampling member, Such arrangements provide the advantage of an improved conduction of heat from the sampling member to the first chamber.

In a preferred arrangement the part of each heat conduction member within each is sampling member has a larger thermal capacity than the part of each heat conduction member within each first chamber.

Preferably the part of each heat conduction member within each first chamber is between 10 -20 % of the length of the part of each heat conduction member within each sampling member.

Preferably each first chamber further includes a second filter. Preferably each second filter defines a second chamber. Such a second filter is after each first filter and operates to further remove soot from the exhaust emissions.

Preferably each second chamber is within each first chamber. Preferably each second chamber has a first closable aperture through which each heat conduction member can be removed. Each first closable aperture further provides the advantage of allowing soot to be cleaned from each second chamber.

Preferably each body has a second closable aperture through which each heat conduction member can be removed. Each second closable aperture further provides the advantage of allowing soot to be cleaned from each first chamber.

Preferably each second filter is removable via each second closable aperture.

Each body may have a tapered collar for attachment to one of the plurality of exhaust ducts. Such a tapered collar may reduce unwanted heat conduction away from each body.

According to a fourth aspect of the invention there is provided a method of operating the sampling system according to the third aspect of the invention including: operating at least one of said plurality of valves to place one of the first chambers in fluid communication with the sample duct.

Preferably the method further includes operating at least one of said plurality of valves to place a different one of the first chambers in fluid communication with the sample duct.

Brief Description of the Drawings

Other features of the invention will be apparent from the following description of preferred embodiments shown by way of example only with reference to the accompanying drawings, in which; Figure 1 shows a partial cross section of a device for sampling exhaust emissions according to an embodiment of the invention; Figure 2 shows a partial cross section of an alternative embodiment of the device of Figure 1; Figure 3 shows a partial cross section of an alternative embodiment of the device of Figures 1 and 2; Figure 4 shows an end view of the device of Figures 1 and 2; Figure 5 shows a schematic side view of the device of Figures 1 -3; Figure 6 shows a schematic diagram of an exhaust emission sampling system according to an embodiment of the invention; Figure 7 shows a diagram of a method according to an embodiment of the invention; and Figure 8 shows a diagram of a method according to an embodiment of the invention.

Detailed Description

Figure 1 shows a partial cross section of a device for sampling exhaust emissions according to an embodiment of the invention, generally designated 10. The device 10 is shown to be attached to an exhaust duct 12 of an engine (not shown) of a ship. Such an exhaust duct 12 is generally vertically oriented, as shown in Figure 1, relative to the ship so that exhaust emissions, shown at 14, within the exhaust duct 12 move upwards.

The exhaust emissions 14 are formed by the combustion process of the engine and may include oxides of carbon (COx), oxides of sulphur (SOx), oxides of nitrogen (NOx), and a complex mixture of many other gases and fine particles commonly known as soot.

The device 10 comprises an intake duct 16 which is connected to a body 18. The intake duct 16 is located inside the exhaust duct 12, and the body 18 is secured to the exhaust duct 12 so that it is outside of the exhaust duct 12. The body 18 comprises a tube 20 of steel which is closed at one end by a base plate 22 of steel which is welded to the tube 20. The other end of the tube 20 is closed by a top plate 24 of steel which is removably attached to the tube 20 with a bolt 26. A gasket 28 between the tube 20 and the top plate 24 provides an air tight seal between them. The tube 20, the bottom plate 22 and the top plate 24 define a first chamber 30 within the body 12 which is in fluid communication with the intake duct 16. An outlet port 31 is provided in the first chamber 30 which leads to a gas analyser apparatus 100, shown in Figure 7, which applies a reduced pressure to the outlet port 31. n Figure 1 the intake duct 16 is shown to have a plurality of holes 32 in a sidewall thereof which permit the exhaust emissions 14 from the exhaust duct 12 to enter the intake duct 16 and pass into the first chamber 22. A filter 33, which is tubular in shape, is also provided in the first chamber 30 to filter the exhaust emissions 14 which pass from the intake duct 16 into the first chamber 30. The filter 33 is arranged in the first chamber 30 such that there is a gap between the tube 20 and the sides of the filter 33.

The device 10 also has a heat conduction member 34 which is located in the intake duct 16 and extends into the first chamber 30. In Figure 1 the heat conducting member 34 can be seen through the holes 32 of the intake duct 16 and is a close fit inside the intake duct 16. The heat conduction member 34 is a bar of sintered metal which is porous to the exhaust emissions 14 and which operates to filter them and to conduct heat energy from the exhaust emissions 14 within the exhaust duct 12 into the first chamber 30. The exhaust emissions 14 within the exhaust duct 12 may typically be at about 300°C under normal operating conditions of the ship. The heat conduction member 34 conveys the heat of combustion in the exhaust duct 12 into the first chamber 30 which reduces or minimises the formation of condensation within the device 10, and particularly within the first chamber 30. This is achieved by maintaining the exhaust emissions 14 at a high enough temperature within the device 10 to keep them above their dew point. Such a temperature is about 150°C. It can be seen that the filter 33 is a close fit around the heat conduction member 34 in the chamber first. It can also be seen that the top plate 24 serves to close the tube 20 and also to close one end of the filter 33. Unscrewing the bolt 26 allows the end plate 24 to be removed so that the filter 33 and the heat conduction member 34 can be removed and replaced as required.

In Figure 1 the length of a first portion 36 of the heat conduction member 34 inside the first chamber 30 is about 15% of the length of a second portion 38 of the conduction member 34 inside the intake duct 16. The first portion 36 is about 80mm in length, and the second portion 38 is about 520mm in length. It will be appreciated that the relative dimensions of the first and second portions may be set as appropriate so that the temperature of the exhaust emissions 14 inside the device 10 is kept high enough so that condensation is reduced or minimised within the device 10. Tn one arrangement the second portion 38 has a larger thermal capacity than the first portion 36. In effect the heat conduction member 34 operates as a heat sink for the exhaust emissions 14.

Furthermore the heat conduction member 34 is described as being of metal, but any appropriate material may be used as long as it has the effect of conveying heat energy from the exhaust emissions 14 within the exhaust duct 12 to the first chamber 30.

The heat energy is intended to be retained in the first chamber 30 by isolating the body 18 from unwanted heat conduction paths and by insulating the body 18. Tn the arrangement shown a collar 40 is provided on the exterior of the exhaust duct 12 which has a threaded portion on an internal part thereof The intake duct 16 has a cooperating threaded portion on an external part thereof for attachment to the collar 20. The collar is tapered so that it forms a truncated cone which reduces contact with the base plate 22. The collar 20 is intended to minimise heat loss by conduction from the body 18 to the exhaust duct 12. In one arrangement the base plate 22 is attached to a second base plate 42 with fasteners 44. The two base plate 22, 42 have a heat resistant gasket (not shown) between them which is made from a composite material. The second base plate 42 and the heat resistant gasket function to seal the device 10 to inhibit unwanted exhaust emissions 14 escaping from the device 10. Also shown is a cover 46 which surrounds the tube 20 and the top plate 24 which may be filled with heat insulating material.

In operation a reduced pressure is applied to the outlet port 31 which draws the exhaust emissions 14 from the exhaust duct 12 into the intake duct 16 via the plurality of holes 32. The exhaust emissions 14 are then drawn into the conduction member 34 which filters them. The exhaust emissions 14 are then drawn though the filter 33 and into the first chamber 30. Such an arrangement filters the exhaust emissions 14 twice which helps to remove unwanted soot in the exhaust emissions 14. The conduction member 34 also delivers heat energy into the chamber to reduce or minimise condensation from developing. The exhaust emissions 14 are then drawn through the outlet port 31 indicated by an arrow 47.

Also shown in Figure 1 is an optional support 48 for the intake duct 16. The support 48 is located inside the exhaust duct 12 and may further assist with securing the device 10 to the exhaust duct 12. It will be appreciated that the support 48 allows the exhaust emissions 14 to pass into the duct substantially unimpeded, and in one embodiment the support 48 is a cage. In one arrangement the support 48 operates as a baffle.

Figure 2 shows a partial cross section of an alternative embodiment of the device of Figure 1, generally designated 50. In Figure 2 like features to the arrangements of Figure 1 are shown with like reference numerals. In Figure 2 an edge of the top plate 24 and an internal surface of the body have a cooperating screw thread 52 for removable attachment of the top plate 24 from the tube 20. With this arrangement the gasket 28 provides an air tight seal between the top plate 24 and the tube 20. The top plate 24 is also provided with a handle 54 for turning the top plate 24 to remove it from the tube 20. The filter 33 is shown to have a separate closure plate 56 which is secured in place with a bolt 58. A gasket 60 between the closure plate 56 and an end of the filter 33 provides an air tight seal between them. With the arrangement of Figure 2 there is a gap 62 between the filter 33 and the heat conduction member 34 which may further assist with filtering of the exhaust emissions 14 by allowing larger particles of soot to collect in the gap 62. The gap 62 may be considered to be a second chamber within the first chamber 30. Unscrewing the handle 54 allows access to the first chamber 30 SO that particles of soot can be removed if necessary. Furthermore, unscrewing the bolt 58 and removing the closure plate 56 allows access to the second chamber so that particles of soot can be removed if necessary. Removing the closure plate 56 also allows the filter 33 and the heat conduction member 34 to be removed and replaced as required.

Figure 3 shows a partial cross section of an alternative embodiment of the device of Figures 1 and 2, generally designated 65. In Figure 3 like features to the arrangements of Figure 1 and 2 are shown with like reference numerals. In Figure 3 the top plate 24 is held in place against the tube 20 by a bolt 66. The bolt 66 is threadedly engaged with a cradle 69 which is pivotably connected to the body 20 at 71. When the bolt 66 is screwed into the cradle 69 an end of the bolt 66 abuts the top plate 24 and urges it towards the tube 20 so that the gasket 28 creates an airtight seal between the top plate 24 and the tube 20. When the bolt 66 is unscrewed the cradle 69 can be pivoted relative to the body 20 at 71 50 that the top plate 24 can be removed from the body 20. Once the top plate 24 has been removed the chamber 30 and the closure plate 56 can be accessed.

The closure plate 56 is secured to a tubular support 68 within the chamber 30 with a cooperating thread 72 between the closure plate 56 and the tubular support 68. The tubular support 68 is attached to the base plate 22. The closure plate 56 has a handle 67 so that it can be unscrewed from the tubular support 68. The tubular support 68 has holes in it so that the exhaust emissions 14 can pass from the heat conduction member 34, through the tubular support 68, through the filter 33, and into the chamber 30. Tt will be appreciated that in the embodiment of Figure 3 there is no second chamber which is shown in the embodiment of Figure 2. In Figure 3, the tubular support 68 occupies the space that comprises the second chamber 62 shown in Figure 2. With the arrangements shown in Figure 3, the temperature difference between the exhaust emissions 14 within the exhaust duct 12 and the tubular support 68 is about 40 -45°C when the exhaust emission 14 within the exhaust duct 12 are at about 300°C.

In the arrangements of Figures 1 -3 there are three main stages of filtering of the exhaust emissions 14. Firstly the exhaust emissions 14 are filtered as they pass from the exhaust duct 12 into the heat conduction member 34 as they pass through the holes 32 in the intake duct 16. In this first stage the exhaust emissions 14 travel at least partially radially inward within the heat conduction member 34. Secondly, the exhaust emissions 14 are filtered as they pass along the heat conduction member 14. In this second stage the exhaust emissions 14 travel substantially along the length of the heat conduction member 14. Thirdly, the exhaust emissions 14 are filtered as they pass through the filter 33 in the chamber 30. Tn this third stage the exhaust emissions 14 travel at least partially radially outward through the filter 33 which is tubular in shape. In the embodiment having the support 48, the exhaust emissions 14 may also be partially filtered as they pass through the support 48. The support 48 may provide an initial relatively coarse filter. In a preferred arrangement the filter provided by the heat conduction member 34 is a coarser filter than the filter 33. For example, the heat conduction member 34 may operate to filter the exhaust emissions 14 so that they have a maximum particle size of about 10tm. The filter 33 may further operate to filter the exhaust emissions 14 so that they have a maximum particle size of about 1 tm. In the arrangements shown in Figures 1 -3 the filter 33 is moulded from borosilicate glass and is intended to be a consumable or replaceable item. The heat conduction member 34 may be re-used by removing is and washing it in a suitable solvent such as petrol.

Figure 4 shows an end view, generally designated 70, of the device 10 from the perspective of the arrow 64 shown in Figures 1 and 2. n Figure 4 like features to the arrangements of Figure 1 and 2 are shown with like reference numerals. In Figure 4 the arrangement of the base plate 22, the body 20, and the top plate 24 can be seen which defines the first chamber 30. The arrangement of the filter 33 and the heat conduction member 34 can also be seen in dotted outline.

Figure 5 shows a schematic side view of the device 10 of Figures 1 -3, generally designated 80, from the perspective of arrow 81. In Figure 5 like features to the arrangements of Figure 1 and 2 are shown with like reference numerals. In Figure 5 the outlet port 31 is shown to be in communication with a solenoid valve 82 which is operable to allow the exhaust emissions 14 to pass from the outlet port 31 into a sample duct 84. The sample duct 84 is insulated and heated with electric heating elements to maintain the temperature of the exhaust emissions 14 within the sample duct 84 50 that they are above the dew point. An electrical control cable 86 is also shown for controlling the operation of the solenoid valve 82. Also shown are supports 88 on either side of the device 10 for clamping a part of the sample duct 84 to the device 10. The supports 88 assist with holding the sample duct 84 in place.

Figure 6 shows a schematic diagram of an exhaust emission sampling system according to an embodiment of the invention, generally designated 90. In Figure 6 like features to the arrangements of Figure 1 -5 are shown with like reference numerals. In Figure 6 four devices 10 for sampling exhaust emissions are shown at 92, 94, 96, 98 for location at four respective exhaust ducts (not shown) of a ship. Each of the devices 92, 94, 96, 98 has a respective outlet port 31 and a respective solenoid valve 82 which are controllable by the electrical control cable 86 to deliver exhaust emissions from a particular device 92, 94, 96, 98 to the sample duct 84. The sample duct 84 is in fluid communication with the gas analyser apparatus 100 which has a power source 102 and a control display 104.

In use the exhaust emission sampling system 90 is operated so that one of the outlet ports 31 of one of the devices 92, 94, 97, 98, for example the device 92, is in fluid communication with the sample duct 84. This is achieved by opening the solenoid valve 82 of the device 92 and closing the other three solenoid valves 82 of the devices 94, 96, 98. A reduced pressure in the sample duct 84 is applied by the gas analyser apparatus so that the exhaust emissions 14 within the sample duct 84 travel into the gas analyser 100.

The exhaust emission sampling system 90 provides the advantage of a reduced length of sample duct 84 when compared to the prior art arrangements which require the devices to be in fluid communication with a separate manifold which is in fluid communication with the gas analyser. With the present embodiment of the invention the length of sample duct 84 may be 30% shorter. Such an advantage may be provided by the solenoid valves 82 which are located close to, or adjacent to, each device 92, 94, 96, 98.

Furthermore, the devices 92, 94, 96, 98 provide an improved heating of the exhaust emissions 14 due to the presence of the heat conductive member 34 which avoids the need for the heated manifold of the prior art. Overall, the exhaust emission sampling system 90 of the present embodiment of the invention provides a significant operation and installation cost saving as well as a reduced space requirement when compared to the prior art arrangements. Furthermore, since the present embodiment of the invention is less complex it requires a reduced time for installation when compared to the prior art.

Figure 7 shows a diagram of a method according to an embodiment of the invention, generally designated 110. The method 110 is a method of sampling exhaust emissions in an exhaust duct 12 using a device 10 comprising an intake duct 16 and a body 18 having a first chamber 30, the intake duct 16 is for location in the exhaust duct 12 and for providing fluid communication between the exhaust duct 12 and the first chamber 30. The method includes drawing the exhaust emissions from the exhaust duct 12 into the first chamber 30 via the intake duct 16, as shown at 112. The method including transferring heat energy from the exhaust emissions 14 within the exhaust duct 12 to heat the first chamber 30, as shown at 114.

The method further includes transferring the heat energy using a heat conduction member 34 for conducting heat from the exhaust emissions 14 within the exhaust duct 12 to the first chamber 30. The method further includes filtering the exhaust emissions 14 from the exhaust duct 12. The method further includes performing said filtering using the heat conduction member 34. The method further includes insulating the body 18 from the exhaust duct 12. The method further includes transferring the exhaust emissions 14 from the first chamber 30 to a sample duct 84 via a valve 82 which is adjacent to the body 18. The method further includes using a heat conduction member 34 which has at least a part thereof within the first chamber 30 or the intake duct 16.

The method further includes using a heat conduction member 34 such that the part thereof within the intake duct 16 has a larger thermal capacity than the part thereof within the first chamber 30.

Figure 8 shows a diagram of a method according to an embodiment of the invention, generally designated 120. The method 120 is a method of operating a sampling system comprising a plurality of devices 92, 94, 96, 98 for selectively sampling exhaust emissions 14 from one of a plurality of exhaust ducts 12. Each device 92, 94, 96, 98 comprising a body 18 and a sampling member 16. Each body 18 having a first chamber 30. Each sampling member 16 for location in a respective exhaust duct 12 and for providing fluid communication between the respective exhaust duct 12 and the respective first chamber 30. Each first chamber 30 has an outlet port 31 with a valve 82 which can be selectively opened and closed to place one of said first chambers 30 in fluid communication with a sample duct 84. The method includes operating at least one of said plurality of valves 82 to place one of the first chambers 30 in fluid communication with the sample duct 84, as shown at 122. The method includes operating at least one of said plurality of valves 82 to place a different one of the first chambers 30 in fluid communication with the sample duct 84, as shown at 124.

In the above embodiments the device 10 and the exhaust emission sampling system 90, are described as being fitted to the exhaust duct 12 of a ship (not shown). As such it is intended that the device 10 is retrofitted to the ship as an accessory, or fitted during manufacture of the ship or installation or replacement of the exhaust duct 12.

Accordingly the device 10 and the exhaust emission sampling system 90 are intended to be permanently fitted to the ship to sample exhaust emissions.

In Figures 1 -3 the outlet port 31 is shown to be located towards the bottom of the chamber 30. In another embodiment the outlet port 31 is located away from the bottom of the chamber 30, and preferably towards the top of the chamber 30. This has the advantage that if any condensation should form in the chamber 30 it does not pass into the sample duct 84 and into the gas analyser apparatus 100 which may further help to reduce the possibility of a false reading for the exhaust emissions 14.

Claims

CLAIMS1. A device for sampling exhaust emissions in an exhaust duct, comprising a body and a sampling member, the body having a first chamber, the sampling member for location in the exhaust duct and for providing fluid communication between the exhaust duct and the first chamber, wherein the device further includes a heat conduction member between the sampling member and the first chamber for conducting heat from the exhaust emissions within the exhaust duct to the first chamber.
2. A device according to claim 1, wherein the heat conduction member comprises a first filter.
3. A device according to claim 1 or 2, wherein the heat conduction member comprises a sintered metal member.
4. A device according to claim 1, 2 or 3, wherein the sampling member comprises the heat conduction member.
5. A device according to any preceding claim, wherein the first chamber further includes a second filter.
6. A device according to claim 5, wherein the second filter defines a second chamber.
7. A device according to claim 6, wherein the second chamber is within the first chamber.
8. A device according to claim 6 or 7, wherein the second chamber has a first closable aperture through which the heat conduction member can be removed.
9. A device according to any preceding claim, wherein the body has a second closable aperture through which the heat conduction member can be removed.
10. A device according to claim 9, when appended to claim 5 or 6, wherein the second filter is removable via the second closable aperture.
11. A device according to any preceding claim, wherein the body has a tapered collar for attachment to the exhaust duct.
12. A device according to any preceding claim, wherein the first chamber has an outlet port.
13. A device according to claim 12, wherein the outlet port has a valve which can be selectively opened and closed to place the first chamber in fluid communication with a sample duct.
14. A device according to claim 13, wherein the valve is adjacent to the body.
15. A device according to any preceding claim, wherein at least a part of the heat conduction member is within the first chamber.
16. A device according to claim 15, wherein at least a part of the heat conduction member is within the sampling member.
17. A device according to claim 16, wherein the part of the heat conduction member within the sampling member has a larger thermal capacity than the part of the heat conduction member within the first chamber.
18. A device according to claim 17, wherein the part of the heat conduction member within the first chamber is between 10 -20 % of the length of the part of the heat conduction member within the sampling member.
19. A device as substantially described herein with reference to Figures 1 -4 of the accompanying drawings.
20. A method of sampling exhaust emissions in an exhaust duct using a device comprising a sampling member and a body having a first chamber, the sampling member for location in the exhaust duct and for providing fluid communication between the exhaust duct and the first chamber, the method including: drawing the exhaust emissions from the exhaust duct into the first chamber via the sampling member; and transferring heat energy from the exhaust emissions within the exhaust duct to heat the first chamber.
21. A method according to claim 20, and further including transferring the heat energy using a heat conduction member for conducting heat from the exhaust emissions within the exhaust duct to the first chamber.
22. A method according to claim 20 or 21, and further including filtering the exhaust emissions from the exhaust duct.
23. A method according to claim 22, and further including performing said filtering using the heat conduction member.
24. A method according to any of claims 20 -23, and further including insulating the body from the exhaust duct.
25. A method according to any of claims 20 -24, and further including transferring the exhaust emissions from the first chamber to a sample duct via a valve which is adjacent to the body.
26. A method according to any of claims 20 -25, when appended to claim 21, and further including using the heat conduction member with a part thereof within the first chamber or the sampling member.
27. A method according to claim 26, and further including using the heat conduction member such that the part thereof within the sampling member has a larger thermal capacity than the part thereof within the first chamber.
28. A method according to any of claims 20 -27 as substantially described herein with reference to Figure 6 of the accompanying drawings.
29. A sampling system comprising a plurality of devices for selectively sampling exhaust emissions from one of a plurality of exhaust ducts, each device comprising a body and a sampling member, each body having a first chamber, each sampling member for location in a respective exhaust duct and for providing fluid communication between the respective exhaust duct and the respective first chamber, wherein each first chamber has an outlet port with a valve which can be selectively opened and closed to place one of said first chambers in fluid communication with a sample duct.
30. A sampling system according to claim 29, wherein each valve is adjacent to each body of the plurality of devices.
31. A sampling system according to claim 29 or 30, wherein each device ifirther includes a heat conduction member between each sampling member and each first chamber for conducting heat from the exhaust emissions from one of the exhaust ducts to each first chamber.
32. A sampling system according to claim 31, wherein each heat conduction member comprises a first filter.
33. A sampling system according to claim 31 or 32, wherein each heat conduction member comprises a sintered metal member.
34. A sampling system according to claim 31, 32 or 33, wherein each sampling member comprises the heat conduction member.
35. A sampling system according to any of claims 31 -34, wherein at least a part of each heat conduction member is within each first chamber.
36. A sampling system according to claim 35, wherein at least a part of each heat conduction member is within each sampling member.
37. A sampling system according to claim 36, wherein the part of each heat conduction member within each sampling member has a larger thermal capacity than the part of each heat conduction member within each first chamber.
38. A sampling system according to claim 37, wherein the part of each heat conduction member within each first chamber is between 10 -20 % of the length of the part of each heat conduction member within each sampling member.
39. A sampling system according to any of claims 29 -38, wherein each first chamber further includes a second filter.
40. A sampling system according to claim 39, wherein each second filter defines a second chamber.
41. A sampling system according to claim 40, wherein each second chamber is within each first chamber.
42. A sampling system according to claim 40 or 41, when appended to any of claims 31 -38, wherein each second chamber has a first closable aperture through which each heat conduction member can be removed.
43. A sampling system according to any of claims 29 -42, when appended to any of claims 31 -38, wherein each body has a second closable aperture through which each heat conduction member can be removed.
44. A sampling system according to claim 43, when appended to claim 39 or 40, wherein each second filter is removable via each second closable aperture.
45. A sampling system according to any of claims 29 -44, wherein each body has a tapered collar for attachment to one of the plurality of exhaust ducts.
46. A sampling system as substantially described herein with reference to Figures 1 -5 of the accompanying drawings.
47. A method of operating the sampling system according to any of claims 29 -46 including: operating at least one of said plurality of valves to place one of the first chambers in fluid communication with the sample duct.
48. A method according to claim 47, and further including: operating at least one of said plurality of valves to place a different one of the first chambers in fluid communication with the sample duct.
49. An exhaust duct including a device according to any of claims 1 -19, or a sampling system according to any of claims 29 -46.