System for continuously measuring the emissions of an exhaust gas circuit of a boat

Abstract

The present invention relates to a system (1) for measuring the emissions of a gas circuit (10) of a boat, such as a gas leaving a funnel of the boat. The system (1) comprises first measurement means (11) for measuring a flow rate in the gas circuit (10), sampling means (12) configured to connect the gas circuit (10) to a measurement circuit (13), and second measurement means (14) for measuring a concentration of emissions in the measurement circuit (13), downstream of the sampling means (12). The system (1) comprises a processing unit (2) configured to: receive, from the first measurement means (11), first data indicative of the flow rate; receive, from the second measurement means (14), second data indicative of the concentration of emissions; and determine third data indicative of a quantity of emissions of the gas circuit (10), as a function of the first data and the second data.

Description

[0001] Description

[0002] Title: Continuous measurement system for emissions from a boat's exhaust gas circuit

[0003] technical field

[0004] The present invention relates to the monitoring and quantification of emissions in the maritime field.

[0005] The present invention relates more particularly to a system for measuring emissions from a gas circuit of a boat, in particular carbon dioxide (also called CO2) emissions at the outlet of a boat's chimney.

[0006] The invention will thus find many advantageous applications in the fight against climate change and the search for opportunities to reduce emissions and pollution.

[0007] Previous art

[0008] Currently, there are several methods for estimating emissions from cargo ships, particularly CO2 emissions.

[0009] Some countries or organizations may require shipowners and shipping companies to report the carbon emissions of their fleets. These reports are usually based on standardized emission factors or on specific data provided by the ships. Another method involves measuring the amount of fuel used by ships and applying emission factors to estimate carbon emissions. Fuel consumption data can be obtained from ship logs or onboard tracking and monitoring systems.

[0010] Satellite tracking systems, such as VAIS (Automatic Identification System), can also be used to track ship movements and estimate their carbon emissions based on speed, cargo, and other parameters. These estimates rely on models and empirical data.

[0011] Finally, more precise and reliable methods are being developed. Indeed, it is also possible to directly measure carbon emissions from ships using onboard devices or sensors. These methods provide more accurate data but can be more expensive and complex to implement. For example, remote sensing techniques can be used to monitor the sulfur and CO2 content of ship fuels. After simulation studies of ship smoke flows, detection distances are established, and infrared sensors are installed on the decks of transport vessels.

[0012] Another remote sensing method is based on differential optical absorption spectroscopy, also called DOAS (from "Differential Optical Absorption Spectroscopy"), for example, LP-DOAS (from "Long Path Differential Optical Absorption Spectroscopy"). A sensor is placed near shipping lanes and aimed at a retroreflector on the opposite bank. However, current LP-DOAS systems do not measure CO2, so relative emission factors cannot be easily derived from nitrogen oxide (NOx) / CO2 or sulfur dioxide (SO2) / CO2 ratios. Therefore, a model must be used to calculate the emission rates of air pollutants, or the integrated CO2 concentration must be measured along the path of the light.

[0013] Other solutions employ drones with onboard sensors to measure SO2 and CO2 emissions from a few dozen meters away from the fumes. This detection method, called "sniffing," provides reliable measurements. However, the system is not suited to complex weather conditions such as rain and fog, and due to its limited wind resistance, it is not sufficiently developed for monitoring the tail emissions of ships. Furthermore, the system's wireless communication module uses a single-chip wireless transceiver that is not suitable for long-distance transmission and / or transmission through obstacles. Finally, data is only collected when the drones are deployed and not continuously throughout their flight, resulting in a limited acquisition time.

[0014] In general, the above solutions are limited by a measurement at a given time or over a short period, and correspond to estimates of emissions from remote measurements, at most several tens of meters from the fumes, unlike direct measurements.

[0015] The Applicant therefore submits that there is currently no satisfactory alternative solution for measuring the emissions of a ship that allows for an actual measurement rather than an estimation of emissions, in real time, over the entire duration of a journey.

[0016] Summary of the invention

[0017] The present invention aims to improve the current situation described above. More particularly, the present invention aims to remedy the above drawbacks by proposing a system for measuring emissions from a ship's gas circuit that performs a direct measurement at the level of this gas circuit itself, that is to say, in particular, at the level of the ship's funnels.

[0018] To this end, the object of the present invention relates, in a first aspect, to a system for measuring emissions from a gas circuit of a boat, the system comprising:

[0019] - the first means of measuring a flow rate associated with the gas circuit;

[0020] - means for sampling the gas circuit, configured to connect the gas circuit to a measurement circuit;

[0021] - second means of measuring an emission concentration, associated with said measurement circuit, downstream of said sampling means; and

[0022] - a processing unit, the processing unit being configured to:

[0023] - to receive initial representative flow rate data from the first measurement methods;

[0024] - to receive second representative data on emission concentration, obtained from second measurement methods; and

[0025] - determine third data representative of a quantity of emissions from the gas circuit, as a function of the first data and the second data.

[0026] The system is particularly suited to gas circuits corresponding to the funnels of merchant marine vessels. However, it is understood that the system can also be adapted to a wide variety of gas circuits commonly found on board a ship.

[0027] It is understood here that the sampling means are configured to take a portion of the gas circulating in the gas circuit, i.e. to obtain a gas sample, and to circulate this sample in the measurement circuit.

[0028] It is also understood that the concepts of upstream and downstream will be understood, for the purposes of this application, by taking into account the direction of gas flow within the gas circuit and the measurement circuit, with the gas flowing from upstream to downstream.

[0029] Ship gas systems are sometimes equipped with exhaust gas scrubbers, which target various gases, including sulfur. To account for these scrubbers, especially when secondary measurement methods are associated with the treated gas, sampling methods can be positioned upstream and / or downstream of the scrubber, depending on the measurement objective. For example, upstream sampling methods allow for the measurement of emissions produced by the ship's operation, while downstream sampling methods allow for the measurement of emissions discharged by the ship. A combination of upstream and downstream sampling methods, particularly through a plurality of sampling methods as described below, also allows for the measurement of the efficiency of the onboard scrubber.

[0030] In other words, the processing unit is configured to quantify emissions based on, firstly, the total gas flow rate in the gas circuit, and secondly, the emission concentration of the sample, which is representative of the gas in the gas circuit. The total quantity of emissions is thus derived directly from the product of the two measured values, without any estimation or remote measurement of the emissions.

[0031] Thanks to the present invention, it is therefore possible to monitor ship funnel emissions through direct measurements, guaranteeing accurate, real-time measurements throughout a journey. Data can be received at regular intervals, for example, every 15 seconds, every 5 minutes, or at any frequency desired by a person skilled in the art. Real-time measurement of the gas system, rather than an estimate over a complete journey or a measurement at a specific point along the route, makes it possible to measure and identify differences based on instantaneous environmental conditions, particularly wind, as well as the ship's various navigation modes.

[0032] The processing unit can, of course, be configured to perform additional steps. In particular, the processing unit can be configured to generate a rendering of graphical content representative of third-order data, for example, in conjunction with first-order data, second-order data, or other parameters enabling the analysis of measured emissions, especially in comparison with known state-of-the-art estimates. Such parameters that can be monitored in parallel are described below.

[0033] In an advantageous embodiment of the present invention, the emissions include carbon dioxide emissions, the second means of measurement include means for measuring a carbon dioxide concentration, and the processing unit is configured to determine third data representative of quantities of carbon dioxide emissions.

[0034] Means of measuring carbon dioxide concentration include, for example, a CO2 sensor, in particular of the Senseair® K33 type.

[0035] In an additional embodiment, the second measuring means define, from the measuring circuit, two parallel circuits comprising a first circuit and a second circuit, the second measuring means comprising:

[0036] - at least one emission concentration sensor associated with the first circuit; - at least one flow controller associated with the first circuit, upstream of the concentration sensor; and

[0037] - at least two pressure controllers, each of the pressure controllers being associated with one of the parallel circuits.

[0038] The second means of measurement are for example grouped in the form of a cabinet, also called an "analyzer", which brings together all the components necessary for measuring the concentration of emissions.

[0039] Here, we understand that the flow controller allows us to control and adjust the flow rate of the first circuit, that is, the flow rate passing through the sensor. Simultaneously, the pressure controllers regulate the pressure in both the first and second circuits. The first pressure controller, associated with the first circuit, is, for example, located downstream of the concentration sensor. It is assumed, for instance, that the flow rate and pressure passing through the sensor are fixed to ensure consistent concentration measurements.

[0040] In one embodiment, the first measurement means include at least one Pitot probe.

[0041] It is understood that a Pitot tube, or Pitot probe, allows for the measurement of fluid velocity. The use of Pitot tubes thus enables the measurement of the flow rate or flux of fumes in the gas circuit. For example, two Pitot tubes are used to measure the total flux of fumes emitted in the gas circuit, ideally at the same frequency as the second set of measurement devices.

[0042] Those skilled in the art understand that using a Pitot tube allows for high measurement accuracy over a wide flow range. A Pitot tube enables measurements to be taken through a single penetration of the gas circuit, maintaining a small profile within the circuit to minimize permanent pressure loss and conserve energy.

[0043] The Applicant also submits that the Pitot tube has measurement limitations, particularly at low or nuisance flow rates, especially when the vessel is stationary. However, the Applicant believes that the measurement error is less than 3% and that the emission levels when the vessel is stationary are negligible compared to emission levels during voyages, particularly at cruising speed. Therefore, the limitations of using Pitot tubes have little impact on the system's accuracy.

[0044] In a further embodiment, the system also includes a gas conditioner, associated with the measurement circuit downstream of the sampling means and upstream of the second measurement means.

[0045] It is understood here that the gas conditioner is configured to modify the gas, coming from the gas circuit and generally corresponding to a hot gas, a gas mixture, and / or a plurality of heterogeneous flows, in order to obtain a controlled gas at the outlet. Thus, the secondary measurement methods operate on a conditioned gas, ensuring a reliable measurement less susceptible to noise. The gas conditioner can, in particular, provide a gas at a fixed temperature at the outlet, or perform other operations such as filtering the gas of other particles or drying the gas by removing water vapor.

[0046] In addition to increasing measurement accuracy, the use of a gas conditioner ensures that the system can withstand harsh conditions over time, particularly high temperatures. Secondary measurement methods are thus subjected to less stress while remaining reliable.

[0047] In yet another embodiment, the sampling means include a gas sampling probe.

[0048] In particular, the gas sampling probe has a DNV GL type examination certificate for special applications on board ships. For example, a compact probe suitable for continuous gas sampling is available, such as the M&C® SP 180-H / MA type.

[0049] In one specific embodiment, the system further comprises a plurality of sampling means, each of the sampling means being configured to connect a gas circuit of the boat to a measurement circuit.

[0050] It is understood here that this design is suitable for measuring, using the same system, emissions from a vessel with multiple gas circuits, or from different points within the same gas circuit, particularly in relation to a scrubber as described above. It is therefore possible to configure the sampling equipment to connect separate gas circuits of the vessel to a measurement circuit. In a specific example, a vessel has eight exhaust stacks associated with the various engines on board, including a main engine for propulsion, two auxiliary engines that alternately generate electricity for the vessel, lateral engines for steering, and a boiler for generating pressurized hot water. In this case, as many sampling devices are required as there are gas circuits.

[0051] Preferably, the system comprises a single measuring circuit, with each sampling device configured to connect each gas circuit to the same measuring circuit. The number of secondary measuring devices, and optionally gas conditioners, depends on the number of measuring circuits.

[0052] The system includes, for example, an aggregator, or multiplexer, for multiple samples, connecting the sampling devices to the measurement circuit. It is also possible to group only some of the sampling devices, and by extension, some of the gas circuits, with the system comprising several measurement circuits associated with the different groupings. For example, two measurement circuits might be used, each configured to analyze half of the ship's gas circuits, or more measurement circuits could perform the same function.

[0053] It is understood here that this improvement allows, via a single system, the measurement of emissions from all the ship's gas circuits. The use of a multiplexer also minimizes the number of components needed downstream of the multiplexer, particularly secondary measurement devices.

[0054] It is also understood that the first means of measurement are associated with the same gas circuits as the means of sampling, in order to obtain the necessary information on the flow rate.

[0055] In yet another embodiment, the system further comprises a server, the server comprising the processing unit, the system further comprising means for transmitting data to the server, the transmission means being configured to communicate with the server during a journey of the boat.

[0056] Here, we understand that the server is a remote electronic device, specifically one not on board the boat, with which communication is established. The server is therefore separate from the gas system, the measurement system, and more generally, from the other system components. The transmission means are thus configured to communicate over long distances, between the boat's actual position and the server, throughout the entire journey, despite the distance. In particular, the transmission means are configured, in accordance with the design of the processing unit, to transmit the first and second data points to the processing unit.

[0057] For example, specific communication solutions are planned for data transfer in the maritime context, enabling tracking throughout sea voyages, including RaaLabs® type solutions.

[0058] In particular, it is understood that the implementation of the processing unit on the server allows for remote data centralization, in order to facilitate the monitoring of the boat's emissions, as well as the processing of this data, particularly in parallel with ancillary data such as meteorological data, the access to which is simplified.

[0059] In one embodiment, the first and second measuring means communicate directly and independently with the transmission means. It is understood here that each measuring instrument is configured to transfer data directly and independently, without additional architecture.

[0060] In another embodiment, the system further comprises a control unit in communication on the one hand with the first measuring means and the second measuring means, and on the other hand with the transmission means.

[0061] The control unit is a device that communicates with the system's sensors. For example, the control unit is configured to aggregate and timestamp data for transmission. The control unit thus acts as a gateway for data transmission. A Moxa ioThinx® gateway, for instance, is used, which is connected via a wired connection to a network communication device, such as an Edge® device, for data transmission to the server. Communication between the gateway and the network communication device is, for example, wired, using a Modbus RTU protocol.

[0062] In one particular example, it is also envisaged that the control unit is disposed inside the analyzer described above, which then combines the second means of measurement and the means of transmission in a compact and secure design.

[0063] In another embodiment, the system further comprises a central unit in communication with the first measuring means and the second measuring means, the central unit comprising the processing unit.

[0064] It is understood here that the central processing unit is configured to centralize and process data, specifically to determine third-party data locally. This third-party data can then be transmitted remotely, or the central processing unit can obtain other ancillary data to perform further processing.

[0065] It is understood here that, unlike the remote server, the central processing unit (CPU) is a device located near the rest of the system. The CPU is preferably configured to be installed on the boat. The CPU can also communicate via wired connection with the other system components. This design is particularly advantageous for monitoring numerous boat-related data, notably for tracking emissions based on boat operating parameters, such as fuel consumption, the operation of onboard engines, and current weather conditions. For example, the system is expected to include additional sensors for monitoring and comparing such supplementary data.This design is also relevant for the potential addition of onboard system control functions for the vessel, particularly based on measured data, for example, in an effort to reduce emissions. Furthermore, this design allows for the transmission of a minimal amount of data during the transmission of third-party data, as calculations are performed before transmission to minimize communication requirements.

[0066] In yet another embodiment, the system further includes means for purging the measuring circuit and / or first measuring means.

[0067] It is understood that the purging methods allow for the recalibration of the first and / or second measuring instruments, thus preventing any drift in measurements, particularly due to fouling or wear of the instruments used. Purging corresponds, for example, to cleaning the measuring circuit with liquid nitrogen and / or compressed air. Such purging can be performed throughout the entire measuring circuit, or specifically at the level of the first and / or second measuring instruments, for example, inside the analyzer as described above.

[0068] The integration of purging means thus makes it possible to ensure reliable measurements over time, particularly along a boat's journey without requiring separate maintenance operations, which would generally require the boat to be docked.

[0069] The processing unit is configured, for example, to control the purging means, for example, based on the detection of a disturbance in the second data.

[0070] In a preferred example, the processing unit is configured to activate the purging means on a regular basis, for example every three days.

[0071] In one embodiment, the processing unit is configured to perform a correction of the first and / or second data, with the third data being determined based on the corrected data.

[0072] In particular, the processing unit is configured to eliminate erroneous data related to micro-perturbations at the level of the measuring means and / or to correct a drift of the measuring means resulting from their soiling and / or wear.

[0073] The processing unit is configured, for example, to compare the first and / or second data points against a set of threshold values, and to eliminate data exceeding those threshold values. The set of threshold values ​​might correspond, for example, to:

[0074] - ranges of normal values ​​for the measured data, for example a gas circuit flow rate between 10,000 and 80,500 kg / h relative to the boat's dimensions; and / or

[0075] - ranges of values ​​derived from estimates of said first and / or second data, for example from models of the boat's operation. The processing unit is also configured, for example, to activate the purging means described above in the event of continuous reception of erroneous data, in order to correct a drift in the measuring means.

[0076] In one embodiment, the system comprises a plurality of second means of measurement associated with a plurality of compounds, the processing unit being configured to receive second data representative of an emission concentration of each of the compounds and to determine third data representative of an emission quantity of each of the compounds through the gas circuit.

[0077] The plurality of compounds corresponds, for example, in addition to the CO2 mentioned above, to a variety of compounds likely to be produced during the operation of the vessel, particularly its engines, and whose measurement is useful to those skilled in the art, especially greenhouse gases. These compounds include, for example, methane (CH4), carbon monoxide (CO), water (H2O), nitrogen monoxide (NO), nitrogen dioxide (NO2), sulfur dioxide (SO2), etc. A dedicated sensor is provided for each compound measured. The plurality of secondary measurement methods are, for example, grouped in a single device, such as the analyzer as described above, or in separate devices, connected in series or parallel on the measurement circuit.

[0078] It is understood here that, since the determination of the third data is based on the link between the total flux and the concentration of a specific compound to determine a quantity of emissions of that compound, such a relationship is easily adaptable to a variety of compounds, which can be measured jointly.

[0079] In yet another embodiment, the system further comprises third means for measuring parameters of the boat, the parameters belonging to a set of parameters comprising:

[0080] - the operation of a boat engine;

[0081] - the boat's fuel consumption;

[0082] - a boat trip; and

[0083] - boat navigation conditions, the processing unit being configured to receive information representative of the parameters, from third means of measurement.

[0084] The boat's navigation conditions include, for example, the sea state around the boat, the presence of ocean currents, wind direction and / or speed, and generally any environmental condition that could affect the boat's operation and movement. It is understood that receiving such parameters allows for the centralization of data useful for assessing the boat's emissions. The combined use of third-party data and parameters makes it possible to establish, or not, correlations between the parameters and the emissions generated, for example, to identify the presence or absence of variations due to the boat's engine speed.This design also allows the operation of the measurement according to the present invention to be compared with other estimation techniques known in the prior art, for example to compare the reliability of the different methods or to detect and correct a variation in the behavior of the measurement system with respect to other parameters, for example a drift of sensors.

[0085] The Applicant submits, in particular, that when using such a system, the discrepancies obtained in measured and estimated emissions demonstrate that applying a constant proportional to fuel consumption, as known in the prior art, does not provide a relevant estimate of emissions. This system also generally reveals that known methods for estimating CO2 overestimate the actual amount emitted compared to the amount actually measured. In particular, these methods cannot take into account parameters such as the presence of favorable winds, which result in lower emissions for the same speed and fuel consumption. Furthermore, the estimation methods do not allow for measuring the positive impact of adding rigid sails to the boat, which the system according to the invention makes possible.In addition, fuel consumption-based estimation methods also exhibit inaccuracies when the boat is stationary, due to a lack of reliability in fuel consumption measurement, particularly when using a Pitot tube for this purpose.

[0086] As stated above, the processing unit can render graphical content representative of the parameters listed above, preferably together with the third data, for example within a common graph.

[0087] Thus, through the various functional and structural technical characteristics above, the Applicant proposes a system for measuring emissions from a gas circuit of a boat with a precision superior to prior art estimation techniques, and allowing direct and continuous measurement of emissions throughout the boat's journeys.

[0088] Description of the figures

[0089] Other features and advantages of the present invention will become apparent from the description of the particular and non-limiting embodiments of the present invention below, with reference to the attached Figures 1 to 12, on which: [Fig i]

[0090] Figure 1 schematically illustrates a system for measuring the emissions of a gas circuit, according to a first embodiment of the present invention;

[0091] [Fig.2]

[0092] Figure 2 schematically illustrates a system for measuring the emissions of a plurality of gas circuits, according to a second embodiment of the present invention;

[0093] [Fig-3]

[0094] Figure 3 schematically illustrates a cabinet containing secondary measuring instruments and a control unit of a system conforming to Figure 1 or 2;

[0095] [Fig.4]

[0096] Figure 4 schematically illustrates second means of measurement of a system conforming to figure 1 or 2;

[0097] [Fig. 5]

[0098] Figure 5 schematically illustrates a processing unit of a system conforming to Figure 1 or 2;

[0099] [Fig.6]

[0100] Figure 6 schematically illustrates a method for determining emission quantities from a gas circuit, implemented by a treatment unit conforming to Figure 5;

[0101] [Fig-7]

[0102] Figure 7 illustrates a first graph representing a quantity of emissions, a flow rate, a fuel consumption and engine speed of a boat, measured by a system conforming to Figure 1 or 2;

[0103] [Fig.8]

[0104] Figure 8 illustrates a second graph representing a quantity of emissions measured by a system conforming to Figure 1 or 2;

[0105] [Fig.9]

[0106] Figure 9 illustrates a third graph representing an estimated quantity of emissions, according to prior art methods;

[0107] [Fig.10]

[0108] Figure 10 illustrates a fourth graph representing fuel flow as a function of engine speed of a boat, measured by a system conforming to Figure 1 or 2; [Fig.11]

[0109] Figure 11 illustrates a fifth graph representing a favorable wind force and a ratio between emissions and fuel consumption, measured by a system conforming to Figure 1 or 2; and

[0110] [Fig.12]

[0111] Figure 12 illustrates a sixth graph representing a quantity of emissions of a plurality of compounds, measured by a system conforming to Figure 1 or 2.

[0112] Detailed description

[0113] A system for measuring emissions from a gas circuit of a boat will now be described in what follows with joint reference to figures 1 to 12. The same elements are identified with the same reference signs throughout the description that follows.

[0114] As stated in the preamble to the description, current solutions for determining a ship's emissions are based on estimates and remote spot measurements, resulting in a lack of measurement reliability and details on the evolution of emissions during a journey.

[0115] One of the objectives of the present invention is to propose a system allowing as direct a measurement as possible of the emissions of ships, adapted to a continuous measurement without approximate estimation of emissions.

[0116] This is made possible in the example described below, which considers the measurement of emissions on a merchant marine vessel, more specifically on the gas circuits corresponding to the chimneys of this vessel.

[0117] It should be understood that this example is not limiting and that the system according to the invention can be adapted to a wide variety of gas circuits on a variety of boat models. Such a system could also be adapted to other gas circuits with fewer or the same constraints as those found on boats.

[0118] Furthermore, emissions preferably include CO2 emissions, particularly within the framework of a carbon footprint assessment associated with the vessel or, more generally, any study aimed at quantifying and / or analyzing emissions associated with maritime activity. It is understood, however, that such a system also applies to a variety of other emissions for which measurement may prove useful to those skilled in the art, either as a complement to or replacement for CO2 emissions measurements.

[0119] According to the example in Figures 1 and 2, an emissions measurement system 1, 1' developed within the framework of the present invention is associated with a gas circuit 10 of a vessel. Figure 1 illustrates a system 1 adapted to one or more gas circuits 10, while Figure 2 illustrates a variant of the system 1' adapted to a plurality of gas circuits 10, 10', in particular a variant comprising several equivalent examples of the same means, denoted by an apostrophe. In particular, a merchant marine vessel generally comprises a plurality of gas circuits 10, 10', also called exhaust stacks, associated with the main engine, auxiliary engines, side engines, or a boiler. The system 1, 1' can thus be adapted to each of these gas circuits 10, 10'.

[0120] The system 1, 1' thus includes first means 11, 11' for measuring the flow rate associated with the gas circuit 10, 10'. The first means 11, 11' include, for example, at least one Pitot tube, preferably two Pitot tubes per gas circuit 10, 10'. The first means 11, 11' are configured to measure the total smoke flow circulating through each gas circuit 10, 10'. As stated previously, for continuous monitoring of emissions during the vessel's journeys, the measurement can be performed continuously and / or at regular intervals. The first means 11, 11' can therefore be directly implemented on the gas circuit 10, 10', and allow the determination of the total quantity of smoke emitted by the vessel.

[0121] In the same example, the system 1, 1' includes sampling means 12, 12' configured to connect the gas circuit 10, 10' to a measuring circuit 13, 13'. The sampling means 12, 12' include, for example, a gas sampling probe per gas circuit 10, 10', for example, an M&C® type probe version SP180-H / MA.

[0122] The measurement circuit 13, 13' is defined as a dedicated circuit, separate from the gas circuit 10, 10', on which measurements can be carried out in a controlled manner. The measurement circuit 13, 13' is thus supplied upstream by the gas circuit 10, 10', and downstream terminates at a separate outlet, for example, back on the gas circuit 10, 10'. In the present example, the outlet of the measurement circuit 13, 13' is of no particular importance, as the fumes produced by the boat are discharged into the outside atmosphere.

[0123] In a particular example, the gas circuit 10, 10' is equipped with an exhaust gas scrubber. The sampling means 12, 12' can be arranged upstream and / or downstream of such a scrubber, depending on the desired measurements, the impact of such a scrubber on these measurements, as well as the possibility of arranging the sampling means 12, 12' relative to the scrubber, with respect to the sizing of the gas circuit 10, 10'.

[0124] It is thus possible to provide for a plurality of sampling means 12, 12'. In particular, system 1 can include several sampling means 12, 12' for the same gas circuit 10, 10', but above all a plurality of sampling means 12, 12' associated with a plurality of gas circuits 10, 10'. It is further understood that, in all embodiments, the first measuring means 11, 11' are associated with the same gas circuits 10, 10' as the sampling means 12, 12', so that the measurements are carried out on the same gas flows.

[0125] Advantageously, directly downstream of the sampling means 12, 12', a multiplexer 16, 16' is provided, configured to connect a plurality of gas inlets to the same measurement circuit 13, 13'.

[0126] Thus, in the example in Figure 2, system 1' comprises a first multiplexer 16 associated with a first set of gas circuits 10 and sampling means 12, and a second multiplexer 16' associated with a second set of gas circuits 10' and sampling means 12'. For a boat with eight exhaust stacks, each multiplexer 16, 16' is, for example, associated with four gas circuits 10, 10' and sampling means 12, 12', with one sampling means 12, 12' per gas circuit 10, 10'. Thus, the first multiplexer 16 defines a first measurement circuit 13 and the second multiplexer 16' defines a second measurement circuit 13'.

[0127] According to the example in Figure 1, system 1 comprises a single multiplexer 16 associated with the set of sampling means 12 and gas circuits 10, so that all the gas circuits 10 are connected to the same measuring circuit 13.

[0128] In both these examples, the use of 16, 16' multiplexers minimizes the number of 13, 13' measurement circuits, and therefore the associated means.

[0129] In each measurement circuit 13, 13', secondary measurement means 14, 14' for measuring emission concentrations are provided. These secondary measurement means 14, 14' are thus arranged downstream of the sampling means 12, 12' and the multiplexer 16, 16'. The secondary measurement means 14, 14' include, in particular, suitable means for measuring the concentration of the compound(s) measured by system 1, 1', notably a CO2 sensor, for example, of the Senseair® K33 type. For example, for each compound measured by system 1, 1', specific secondary measurement means 14, 14' are provided, for example, arranged in series in the measurement circuit 13, 13'.

[0130] As illustrated in Figures 3 and 4, the second measuring means 14, 14' define two parallel circuits 13a, 13b originating from the measuring circuit 13. An emission concentration sensor 141, for example the CO2 sensor mentioned above, is connected to the first circuit 13a. The flow between the two parallel circuits 13a, 13b can then be adjusted to ensure a reliable measurement by the emission concentration sensor 141. A flow controller 142 is thus provided on the first circuit 13a, along with two pressure controllers 143a, 143b connected to the parallel circuits 13a, 13b. The flow controller 142 is preferably located upstream of the concentration sensor 141, and the first pressure controller 143a is located downstream of the concentration sensor 141.The flow controller 142 allows the flow rate to be adjusted up to the concentration sensor 141, while the pressure controllers 143a, 143b allow the pressure to be adjusted in the two parallel circuits 13a, 13b.

[0131] As illustrated in Figures 2 and 3, the second measuring means 14, 14', i.e. the concentration sensor 141, the flow controller 142 and the pressure controllers 143a, 143b, are grouped in a cabinet 100, 100', i.e. in a housing forming an external enclosure and grouping the second measuring means 14. The cabinet 100, 100' may advantageously include other elements, in particular a control unit 18 as described below in accordance with Figure 3. In the example of Figure 2, the cabinet 100' includes the plurality of measuring circuits 13, 13' and all associated elements, from the multiplexers 16, 16'.

[0132] Specifically, in this same example, as well as in the example in Figure 1, the measurement circuit 13, 13' includes a gas conditioner 15, 15' located upstream of the second measurement means 14, 14', and downstream of the sampling means 12, 12' and the multiplexer 16, 16'. Like the flow controller 142 and the pressure controllers 143a, 143b, the gas conditioner 15, 15' allows for the regulation of the gas in the measurement circuit 13, 13'. The gas conditioner 15, 15' is, for example, configured to regulate the gas temperature, as the circulation in the gas circuits 10, 10' corresponds to hot fumes that could damage the second measurement means 14, 14'. The 15, 15' gas conditioner also allows for the regulation of heterogeneous flows or the different gases constituting the smoke, for example by regulating the moisture content of the smoke.In addition, conditioning the gas in the measuring circuits 13, 13' at a controlled temperature and / or pressure ensures accurate measurement and facilitates the following calculations.

[0133] Similarly, as illustrated in Figure 2, the system 1' advantageously includes purging means 19a, 19a', 19b, 19b'. For example, first purging means 19a, 19a' are associated with the first measuring means 11, 11', and second purging means 19b, 19b' are associated with the second measuring means 14, 14', or more generally with the measuring circuit 13, 13'. The purging means 19a, 19a', 19b, 19b' thus allow the measuring means to be cleaned and recalibrated, ensuring reliable measurements over the long term. The purging means 19a, 19a', 19b, 19b' allow, for example, cleaning with liquid nitrogen, compressed air, or any other suitable fluid.

[0134] As illustrated in Figures 1 and 5, the system 1, 1' further comprises a processing unit 2, which is configured to implement a method for determining the quantity of emissions from the gas circuits 10, 10' of the vessel, for example, method 3 in Figure 6. The processing unit 2 is configured, for example, to transmit and receive data within a communication network. The elements of the processing unit 2, individually or in combination, can be integrated into a single integrated circuit, into several integrated circuits, and / or into discrete components. The processing unit 2 can be implemented as electronic circuits or software (or computer) modules, or a combination of electronic circuits and software modules.

[0135] The processing unit 2 comprises one (or more) processors 21 configured to execute instructions for carrying out the steps of the process 3 and / or for executing instructions from the software embedded in the processing unit 2. The processor 21 may include integrated memory, an input / output interface, and various circuits known to those skilled in the art. The processing unit 2 further comprises at least one memory 20, for example, volatile and / or non-volatile memory, and / or includes a memory storage device that may include volatile and / or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic disk, or optical disk.

[0136] The computer code of the embedded software(s) including the instructions to be loaded and executed by the processor 21 is for example stored on the memory 20 of the processing unit 2.

[0137] According to one embodiment, the processing unit 2 is configured for the implementation of a method for determining the emissions of the gas circuits 10, 10' of the boat, which is part of a larger method comprising one or more emission analysis steps, in which the quantities calculated during the method according to the invention, in particular the third data, are used as input data for subsequent analyses.

[0138] In a first step 31 of the emission determination process, the processing unit 2 receives initial data representative of the flow rate from the first measuring means 11, 11', and in a second step 32 of the process 3, the processing unit 2 receives second data representative of the emission concentration from the second measuring means 14, 14'. The initial and / or second data are, for example, received by a beacon unit 22 of the processing unit 2. In a first variant, the system 1, 1' comprises a server located remotely from the vessel, the server comprising the processing unit 2. In other words, the processing unit 2 is located remotely from the vessel and receives the initial and second data via a wireless link.As illustrated in Figure 1, the system 1, 1' includes, for example, means for transmitting data 17, to the server and the processing unit 2, corresponding to means dedicated for long-range communication.

[0139] In this same example, system 1, 1' also includes a control unit 18 in communication, on the one hand, with the first measuring means 11, 11' and the second measuring means 14, 14', and on the other hand, with the transmission means 17. The control unit 18 is advantageously integrated into the cabinet 100, as shown in Figure 3. The control unit 18 thus forms a gateway between the measuring means and the transmission means 17, and allows for data aggregation, time-stamping, etc., for transmission. A Moxa ioThinx® gateway is preferred, forming the control unit 18, in wired communication with an Edge®-type box forming the transmission means 17, the wired communication being carried out, in particular, according to a Modbus RTU communication protocol.

[0140] In another example, the transmission means 17 communicate independently with the first measuring means 11, 11' and the second measuring means 14, 14', meaning that each of the first measuring means 11, 11' and the second measuring means 14, 14' transmits the measured information to the processing unit 2 independently. For example, a plurality of transmission means 17 are provided, directly integrated with the first measuring means 11, 11' and the second measuring means 14, 14', so that each can communicate separately.

[0141] In a second variant, the system 1, 1' comprises a central unit associated with the vessel, i.e., a central unit directly onboard the vessel, as opposed to a remote server. This central unit includes the processing unit 2. The central unit is thus also in communication with the first measuring means 11, 11' and the second measuring means 14, 14' for receiving the first and second data, for example, independently or via a control unit 18 acting as a gateway, as described above. Such a central unit thus enables the implementation of the method 3, and any ancillary functions, directly on the vessel, without requiring long-range communication and in a completely independent manner.The central unit can also perform long-range communications independently, for example, to transmit the results of process 3 to a remote server for updates, etc. Optionally, once the first and / or second data sets are received, the processing unit 2 performs data correction. This correction might involve, for example, eliminating erroneous data due to sensor disturbances, particularly by removing data significantly different from their usual values, correcting instrument drift due to soiling and / or wear of the measuring instruments, or using any other correction technique known to those skilled in the art.The processing unit 2 can also be configured to control the purge means 19a, 19a', 19b, 19b' according to detected disturbances, for example via a control circuit 23 integrated into the processing unit 2 and in communication with the purge means 19a, 19a', 19b, 19b'.

[0142] In a third step 33, the processing unit 2, for example the processor 21, determines third data points representing a quantity of emissions from the gas circuit 10, 10'. These third data points are determined, for example, at regular intervals to track changes in the quantity of emissions. For instance, the first and second data points are received, and the third data points are determined, at the same interval, for example, every 15 seconds, every 5 minutes, or at any interval deemed appropriate by those skilled in the art and relevant to the duration of a vessel's journey and the variability of conditions. It is understood that since the measurements are taken directly on the gas circuit 10, 10' on board, the data can be received continuously throughout the journey.

[0143] The processor can thus determine, for a given compound, for example for CO2, a volumetric flow rate Fv CO2, based on the following formula:

[0144] [Math. l]

[0145] FVCO2 = Fvtotal * PcO2

[0146] Where Fvtotai is the volumetric flow rate measured by the first measuring means 11, 11' and obtained from the first data, and Pco2 is the percentage of CO2 concentration measured by the second measuring means 14, 14' and obtained from the second data. F v CO2 and Fvtotai are, for example, expressed in m 3 / h. Such a formula can be applied separately for each measured 10, 10' gas circuit, or jointly for any 10, 10' gas circuit having the same CO2 concentration.

[0147] The ideal gas law can be applied to CO2 so that: [Math.2] m PV = nRT = -RT M With P the pressure, n the amount of substance, M the molar mass of the gas, R the ideal gas constant, T the temperature, m the mass of the gas and V the volume of the gas.

[0148] Such a formula can be applied to relate the volumetric flow rate F v CO2 at mass flow rate F m CO2, replacing the volume V and mass m respectively, so that:

[0149] With Kparfait a constant that can be calculated for any ideal gas, with a value of 44.30 mol / m³ 3 , with a reference pressure P of 101.325 kPa, R equals 8.314 Pa.m 3 .mol' 1 .K' 1 , and a reference temperature of 273.15K.

[0150] Thus, the actual quantity of CO2 associated with the gas circuit 10, 10' can be obtained directly from the first and second data points, via the formula:

[0151] [Math.4]

[0152] With F m CO2, the quantity of CO2 emitted via the gas circuit, 10, 10' in gh' 1This quantity can be summed between all the gas circuits 10, 10' to obtain a total quantity of CO2, corresponding for example to all the emissions of the boat.

[0153] It is understood here that such a formula can be applied, in a similar way, to any other compound for which the ideal gas law is appropriate, starting from the same volumetric flow rate measured by the first measuring means 11, 11' and a concentration of the associated compound measured by the second measuring means 14, 14'. The treatment unit 2 can thus determine a quantity of carbon dioxide emissions as well as a wide variety of other compounds.

[0154] Processing unit 2 can advantageously be configured to generate graphic content representative of the third data. Processing unit 2 communicates, for example, with a human-machine interface, via beacon unit 22 or another dedicated unit, in order to allow the display of graphic content representative of the determined emission quantities.

[0155] In particular, system 1 may include third means of measuring vessel parameters, with processing unit 2 receiving representative information about the parameters through communication with these third means. Graphic content is then generated based on these parameters. Processing unit 2 may also perform additional calculations based on these parameters, depending on the type of analysis required. Generally, processing unit 2 centralizes the data associated with the vessel's emissions.

[0156] Such parameters include, for example:

[0157] - the operation of a boat engine;

[0158] - the boat's fuel consumption;

[0159] - a boat trip; and

[0160] - the navigation conditions of said boat.

[0161] The graphic content corresponds, for example, to one or more of the graphs illustrated in figures 7 to 12.

[0162] Thus, the first graph 4 in Figure 7 illustrates the evolution, over time 41, of a plurality of variables including:

[0163] - a flow rate of 42 from the gas circuits 10, 10';

[0164] - a quantity of CO2 43 determined according to the process;

[0165] - a fuel consumption of 44 for the boat; and

[0166] - a boat engine speed of 45.

[0167] The first graph, 4, illustrates that the flow rate 42 and the quantity of CO2 43 determined by the process are correlated, suggesting that the CO2 concentration in the exhaust fumes is essentially constant. Conversely, variations in fuel consumption 44 do not appear to be related to either the engine speed 45 or the quantity of CO2 43 emitted. Therefore, the estimation method, known to those skilled in the art, of applying a constant proportional to the fuel consumed to estimate CO2 emissions does not appear to be reliable.

[0168] The second graph 5 in Figure 8 illustrates the evolution, over time 51, of the quantity of CO2 measured 52 (in t / h) by the process according to the invention and of the engine speed 53 (in revolutions per minute). In parallel, the third graph 6 in Figure 9 illustrates the evolution, over time 61, of the quantity of CO2 estimated 62 (in t / h) based on fuel consumption, as well as the evolution of the engine speed 63 (in revolutions per minute).

[0169] Figures 5 and 6 illustrate a significant difference between the direct measurement via system 1, 1' according to the invention and known estimation techniques, of approximately 1.2 t / h in the example considered. The estimation techniques thus overestimate the actual quantity of emissions. In particular, a difference remains even when the engine is off.

[0170] The fourth graph 7 illustrates the different measured values ​​of fuel consumption 72 as a function of engine speed 71. It then appears that a fuel flow remains measured, even when the engine is stopped, which can be attributed to the measurement limits of the probes used to measure the fuel flow, and further limits the accuracy of the emission estimates compared to a direct measurement according to the invention.

[0171] The fifth graph 8 in Figure 11 illustrates the evolution, over time 81, of a ratio

[0172] 82 between the measured amount of CO2 and the fuel consumed, as well as a favorable wind force of 83, on a boat equipped with rigid sails. The ratio 82 is thus derived from the third set of data and a fuel consumption measurement, while the favorable wind force

[0173] 83 is derived from external navigation conditions (wind direction and intensity) and the ship's route. This fifth graph, 8, shows that the ratio 82 varies over time and decreases when the ship's trajectory follows the wind direction. System 1, 1' thus allows us to monitor the effectiveness of measures aimed at reducing emissions.

[0174] Finally, the sixth graph 9 of Figure 12 illustrates the evolution, over time 91, of the emissions of a plurality of compounds measured by system 1, 1' according to the invention, including:

[0175] - a quantity of CO2 92 (in t / h);

[0176] - a quantity of CO 93 (in kg / h);

[0177] - a quantity of NO 94 (in kg / h);

[0178] - a quantity of NO2 95 (in kg / h);

[0179] - a quantity of SO2 96 (in kg / h); and

[0180] - a quantity of CH4 97 (in kg / h).

[0181] Thus, it will be understood that the present invention provides a system for measuring emissions from a ship's gas system, which allows for the quantification of emissions of a variety of compounds produced during a ship's journey, including CO2. This quantification is performed using direct and continuous measurements, greatly increasing the accuracy of the measurements compared to known prior art solutions. This increased accuracy makes it possible to better determine the positive or negative impact of navigation practices and emission reduction techniques.

[0182] It should be noted that this detailed description relates to a specific embodiment of the present invention, but in no way does it limit the scope of the invention; on the contrary, its purpose is to eliminate any possible ambiguity or misinterpretation of the following claims. It should also be noted that the reference symbols placed in parentheses in the following claims are not intended to be limiting; their sole purpose is to improve the clarity and understanding of the following claims and the scope of protection sought.

Claims

Demands 1. System (1) for measuring emissions from a gas circuit (10) of a ship, said system (1) comprising: - the first means of measuring (11) a flow rate (42) associated with said gas circuit (10); - sampling means (12) of said gas circuit (10), configured to connect said gas circuit (10) to a measurement circuit (13); - second means of measuring (14) a concentration of emissions, associated with said measurement circuit (13), downstream of said sampling means (12); and - a processing unit (2), said processing unit (2) being configured to: - receive (31) the first representative data of said flow (42), from said first means of measurement (11); - receive (32) second representative data on said emission concentration, from said second means of measurement (14); and - determine (33) third data representative of a quantity of emissions (92, 93, 94, 95, 96, 97) from said gas circuit (10), as a function of said first data and said second data.

2. System (1) according to claim 1, wherein said emissions include carbon dioxide emissions, said second measuring means (14) comprising means for measuring a carbon dioxide concentration and said processing unit (2) being configured to determine third data representative of quantities of carbon dioxide emissions (92).

3. System (1) according to claim 1 or 2, wherein said second measuring means (14) define, from said measuring circuit (13), two parallel circuits (13a, 13b) of which a first circuit (13a) and a second circuit (13b), said second measuring means (14) comprising: - at least one emission concentration sensor (141) associated with said first circuit (13a); - at least one flow controller (142) associated with said first circuit (13a), upstream of said concentration sensor (141); and - at least two pressure controllers (143a, 143b), each of said pressure controllers (143a, 143b) being associated with one of said parallel circuits (13a, 13b).

4. System (1) according to any one of claims 1 to 3, wherein said first measuring means (11) comprise at least one Pitot probe.

5. System (1) according to any one of claims 1 to 4, further comprising a gas conditioner (15), associated with said measuring circuit (13) downstream of said sampling means (12) and upstream of said second measuring means (14).

6. System (1) according to any one of claims 1 to 5, wherein said sampling means (12) comprise a gas sampling probe.

7. System (1) according to any one of claims 1 to 6, further comprising a plurality of sampling means (12), each of said sampling means (12) being configured to connect a gas circuit (10) of said boat to a measuring circuit (13).

8. System (1) according to any one of claims 1 to 7, further comprising a server, said server comprising said processing unit (2), said system (1) further comprising means for transmitting data (17) to said server, said transmission means (17) being configured to communicate with said server during a journey of said vessel.

9. System (1) according to claim 8, wherein said first measuring means (11) and said second measuring means (14) are directly in communication with said transmission means (17), independently.

10. System (1) according to claim 8, which further comprises a control unit (18) in communication on the one hand with said first measuring means (11) and said second measuring means (14), on the other hand with said transmission means (17).

11. System (1) according to any one of claims 1 to 7, further comprising a central unit in communication with said first measuring means (11) and said second measuring means (14), said central unit comprising said processing unit (2).

12. System (1) according to any one of claims 1 to 11, further comprising means for purging (19a, 19b) said measuring circuit (13) and / or said first measuring means (11).

13. System (1) according to any one of claims 1 to 12, wherein said processing unit (2) is configured to perform a correction of said first and / or second data, said third data being determined as a function of the corrected data.

14. A system (1) according to any one of claims 1 to 13, comprising a plurality of second measuring means (14) associated with a plurality of compounds, said processing unit (2) being configured to receive (32) second data representative of an emission concentration of each of said compounds and to determine (33) third data representative of a quantity of emissions of each of the said compounds by the said gas circuit (10).

15. System (1) according to any one of claims 1 to 14, further comprising third means for measuring parameters of said boat, said parameters belonging to a set of parameters comprising: - operation of an engine (45, 53, 63, 71) of said boat; - fuel consumption (44, 72) of said boat; - a journey of said boat; and - navigation conditions of said boat, said processing unit (2) being configured to receive information representative of said parameters, from said third means of measurement.

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