Continuous measurement system for emissions from a boat's exhaust gas circuit

Abstract

The present invention relates to a system (1) for measuring emissions from a gas circuit (10) of a vessel. Said system (1) comprises first means for measuring the flow rate of said gas circuit (10), sampling means (12) configured to connect said gas circuit (10) to a measuring circuit (13), and second means for measuring the concentration of emissions from said measuring circuit (13), downstream of said sampling means (12). Said system (1) comprises a processing unit (2) configured to receive first data representative of said flow rate, obtained from said first means (11), to receive second data representative of said emission concentration, obtained from said second means (14), and to determine third data representative of a quantity of emissions from said gas circuit (10), based on said first and second data. Figure 1

Description

Title of the invention: Continuous measurement system for emissions from a boat's exhaust gas circuit. Technical field

[0001] The present invention relates to the monitoring and quantification of emissions in the maritime field.

[0002] The present invention relates more particularly to a system for measuring emissions from a gas circuit of a boat, in particular emissions of carbon dioxide (also called CO2) at the outlet of a boat's chimney.

[0003] The invention will thus find many advantageous applications in the fight against climate change and the search for opportunities to reduce emissions and pollution. Previous art

[0004] Currently, there are several methods for estimating emissions from cargo ships, in particular CO2 emissions.

[0005] Some countries or organizations may require shipowners and shipping companies to report the carbon emissions of their fleets. These reports are generally based on standardized emission factors or on specific data provided by the ships.

[0006] Another method consists of 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 monitoring and tracking systems.

[0007] Satellite tracking systems, such as AIS (Automatic Identification System), can also be used to track ship movements and estimate their carbon emissions based on their speed, cargo, and other parameters. These estimates are based on models and empirical data.

[0008] 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 installed on board. These methods provide more precise data, but can be more expensive and complex to implement.

[0009] It is thus known to implement remote sensing techniques to monitor the sulfur and CO2 content of ship fuels. After studies of Simulations of smoke flows from ships, detection distances are set and infrared sensors are installed on a deck used by transport ships.

[0010] Another remote sensing method is based on differential optical absorption spectroscopy, also called DOAS (from the English "Differential Optical Absorption Spectroscopy"), for example LP-DOAS (from the English "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 concentration of CO2 must be measured along the path of the light.

[0011] Other solutions employ drones with onboard sensors to measure SO2 and CO2 emissions a few tens of meters from the fumes. This detection method, called "sniffing," allows for reliable measurements. However, the system is not suitable for complex weather conditions such as rain and fog, and due to limitations in wind resistance, it is not sufficiently developed for monitoring the tail gases of ships. Furthermore, the system's wireless communication module uses a single-chip wireless transceiver that is not suitable for transmission over long distances and / or through obstacles. Finally, data is only collected when the drones take off and not continuously throughout their flight, so this technique has a limited acquisition time.

[0012] 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.

[0013] 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. Summary of the invention

[0014] The present invention aims to improve the current situation described above.

[0015] The present invention is more particularly aimed at overcoming the following drawbacks: above, by proposing a system for measuring the emissions of a gas circuit of a boat which makes a direct measurement at the level of this gas circuit itself, that is to say in particular at the level of the funnels of a boat.

[0016] To this end, the object of the present invention relates, in a first aspect, to a system for measuring the emissions of a gas circuit of a boat, the system comprising: - the first means of measuring a flow rate associated with the gas circuit; - means for sampling the gas circuit, configured to connect the gas circuit to a measurement circuit; - Second means of measuring emission concentration, associated with said measurement circuit, downstream of said sampling means; and - a treatment unit, the processing unit being configured for: - to receive initial representative flow rate data from the first measurement methods; - to receive second representative data on emission concentration, obtained from second measurement methods; and - determine third data representative of a quantity of emissions from the gas circuit, as a function of the first data and the second data.

[0017] 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.

[0018] 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.

[0019] It is also understood that the notions of upstream and downstream will be understood, within the meaning of this application, by taking into account the direction of gas flow within the gas circuit and the measurement circuit, the gas flowing from upstream to downstream.

[0020] Ship gas systems are sometimes equipped with exhaust gas scrubbers, targeting various gases, including sulfur. To account for these scrubbers, particularly when the secondary measurement means are associated with the scrubbed gas, the sampling means can be positioned upstream and / or downstream of the scrubber, depending on the measurement objective. For example, upstream sampling means allow the measurement of emissions produced by the ship's operation, while downstream sampling means allow the measurement of emissions discharged by the ship. A combination of upstream and downstream sampling means, particularly via a plurality of means The sampling method as described below also allows for the measurement of the efficiency of the on-board purifier.

[0021] In other words, the processing unit is configured to quantify emissions based on, on the one hand, the total gas flow rate in the gas circuit, and on the other hand, 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 a product of the two measured values, without remote estimation or measurement of the emissions.

[0022] Thanks to the present invention, it is therefore possible to monitor ship funnel emissions through direct measurements, guaranteeing accurate, real-time measurements over the entire duration of a journey. The data can, for example, be received at regular intervals, such as every 15 seconds, every 5 minutes, or at any frequency desired by those 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 journey, makes it possible to measure and identify differences based on instantaneous environmental conditions, particularly wind, as well as the ship's various navigation modes.

[0023] The processing unit can naturally be configured to perform additional steps. In particular, the processing unit can be configured to generate a rendering of graphic content representative of third data points, for example, in conjunction with first data points, second data points, or other parameters enabling the analysis of measured emissions, especially in comparison with known prior art estimates. Such parameters that can be monitored in parallel are described below.

[0024] 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.

[0025] Means of measuring a concentration of carbon dioxide include for example a CO2 sensor, in particular of type Senseair® K33.

[0026] 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: - 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 - at least two pressure controllers, each of the pressure controllers being associated with one of the parallel circuits.

[0027] The second means of measurement are for example grouped in the form of a cabinet, also called an "analyzer", which groups together all the components necessary for measuring the concentration of emissions.

[0028] It is understood here that the flow controller allows the flow rate of the first circuit to be controlled and adjusted, that is, the flow rate through the sensor. In parallel, the pressure controllers regulate the pressure in 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 example, that the flow rate and pressure through the sensor are fixed, so as to ensure a consistent measurement of the concentration.

[0029] In one embodiment, the first measurement means include at least one Pitot probe.

[0030] It is understood that a Pitot tube allows the measurement of fluid velocity. The use of Pitot tubes thus allows 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, notably at the same frequency as the second measuring means.

[0031] Those skilled in the art understand that the use of a Pitot tube makes it possible to obtain high measurement accuracy over a wide flow range. A Pitot tube makes it possible to obtain measurements via a single penetration of the gas circuit, maintaining a small profile in the circuit, so as to minimize permanent pressure loss and save the energy required.

[0032] The Applicant also submits that the Pitot tube has measurement limitations, particularly at low or nuisance flow rates, especially when the vessel is stopped. However, the Applicant considers that the measurement error is less than 3% and that the emission quantities when the vessel is stopped are negligible compared to emission levels during voyages, particularly at cruising speed. The limitations of using Pitot tubes are therefore of little consequence to the system's accuracy.

[0033] In an additional embodiment, the system further includes a gas conditioner, associated with the measurement circuit downstream of the sampling means and upstream of the second measurement means.

[0034] 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, so as to obtain a controlled gas at the outlet. Thus, the second measuring means operate on a conditioned gas, making it possible to ensure a reliable measurement less susceptible to noise. The gas conditioner can, in particular, supply a gas at a fixed temperature at the outlet, or perform other functions. operations such as filtering the gas from other particles or drying the gas by removing water vapor.

[0035] 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. The secondary measurement means are thus subjected to less stress while remaining reliable.

[0036] In yet another embodiment, the sampling means include a gas sampling probe.

[0037] In particular, the gas sampling probe has a DNV GL type examination certificate for special application on board ships. For example, a compact probe suitable for continuous gas sampling is provided, for example, of the M&C® type, version SP180-H / MA.

[0038] In a 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.

[0039] It is understood here that this design is suitable for measuring, using the same system, emissions from a vessel comprising multiple gas circuits, or from different points within the same gas circuit, particularly with respect to a scrubber as described above. It is thus possible to configure the sampling means 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 means are required as there are gas circuits.

[0040] 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.

[0041] The system includes, for example, an aggregator, or multiplexer, of a plurality of samples, between the sampling means and the measurement circuit.

[0042] It is also possible to group only some of the sampling means, and by extension the gas circuits, together, the system comprising several measurement circuits associated with the different groupings. For example, two measurement circuits are provided, each configured for the analysis of half of the boat's gas circuits, or more measurement circuits with the same function.

[0043] 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 elements required downstream of the multiplexer, particularly the secondary measurement means.

[0044] 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.

[0045] 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.

[0046] It is understood here that the server corresponds to a remote electronic device, in particular an electronic device not on board the boat, with which communication is established. The server is thus remote from the gas circuit, the measurement circuit, and more generally from the other components of the system. The transmission means are therefore configured to communicate over long distances, between the actual position of the boat and the server, throughout the entire journey, despite the distance. The transmission means are specifically configured, in accordance with the design of the processing unit, to transmit the first and second data to the processing unit.

[0047] For example, specific communication solutions for data transfer in the maritime context are planned, allowing tracking throughout sea voyages, including RaaLabs® type solutions.

[0048] 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.

[0049] In one embodiment, the first measuring means and the second measuring means are directly in communication with the transmission means, independently.

[0050] It is understood here that each measuring instrument is configured to transfer data directly and independently, without additional architecture.

[0051] 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.

[0052] The control unit thus corresponds to a device in communication with the system's sensors. The control unit is, for example, configured to aggregate and timestamp the data for transmission. The control unit thus forms a gateway for data transmission. For example, a Moxa ioThinx® gateway is used, which is connected via a wired connection to a network communication device for data transmission to the server, such as an Edge® device. Communication between the gateway and the network communication device is, for example, wired, using a Modbus RTU communication protocol.

[0053] In a particular example, it is also provided that the control unit is arranged inside the analyzer described above, which then groups the second measuring means and the transmission means in a compact and secure design.

[0054] 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.

[0055] It is understood here that the central processing unit is configured to centralize and process the data, in particular to determine the third data locally. The third data can then be transmitted remotely, or the central processing unit can obtain other ancillary data to perform further processing.

[0056] It is understood here that, unlike the remote server, the central unit corresponds to a device located near the rest of the system. The central unit is preferably configured to be installed on the boat. The central unit can also communicate via wired connection with the other elements of the system. This design is particularly advantageous for monitoring numerous data relating to the boat, notably for monitoring emissions based on boat operating parameters, such as fuel consumption, the operation of onboard engines, and immediate 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.

[0057] In yet another embodiment, the system further includes means for purging the measuring circuit and / or first measuring means.

[0058] It is understood that the purging means allow for a recalibration of the first and / or second measuring means, so as to avoid any drift in the Measurements, particularly due to fouling or wear of the instruments used. Purging, for example, involves cleaning the measurement circuit with liquid nitrogen and / or compressed air. Such purging can be carried out throughout the entire measurement circuit, or specifically at the first and / or second measurement points, for example, inside the analyzer as described above.

[0059] The integration of purging means thus makes it possible to ensure reliable measurements over time, in particular along a journey of the boat without requiring separate maintenance operation, which would generally require the boat to be berthed.

[0060] The processing unit is configured for example to control the purging means, for example based on the detection of a disturbance at the level of the second data.

[0061] According to a preferred example, the processing unit is configured to activate the purging means on a regular basis, for example every three days.

[0062] In one embodiment, the processing unit is configured to perform a correction of the first and / or second data, the third data being determined based on the corrected data.

[0063] 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.

[0064] 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 said threshold values. The set of threshold values ​​corresponds, for example, to: - 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 - intervals of values ​​derived from estimates of said first and / or second data, for example from models of the operation of the boat.

[0065] 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 of the measuring means.

[0066] 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.

[0067] 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 correspond, for example, to methane (CH4), carbon monoxide (CO), water (H2O), nitrogen monoxide (NO), nitrogen dioxide (NO2), sulfur dioxide (SO2), etc. A dedicated sensor is provided, for example, for each compound measured. The plurality of secondary measurement means are, for example, grouped in a single device, such as the analyzer as described above, or in separate devices, assembled in series or in parallel on the measurement circuit.

[0068] 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 adaptable without difficulty to a variety of compounds, which can be measured jointly.

[0069] 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: - the operation of a boat engine; - the boat's fuel consumption; - a boat trip; and - boat navigation conditions, the processing unit being configured to receive information representative of the parameters, from third means of measurement.

[0070] The navigation conditions of the boat correspond for example to a state of the sea around the boat, the presence of sea currents, a direction and / or speed of the wind, and generally to any environmental condition which may affect the operation and movement of the boat.

[0071] It is understood here 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 thus makes it possible to establish, or not, correlations between the parameters and the emissions generated, for example, in order to detect the presence or absence of variations due to the boat's engine speed. This design also makes it possible to compare the operation of the measurement according to the present invention with other estimation techniques known in the prior art, for example, to compare the reliability of different methods or to detect and correct a variation in the behavior of the measurement system with respect to other parameters, for example, sensor drift.

[0072] The Applicant submits in particular that, when using such a system, the discrepancies obtained in the measured and estimated emissions make it possible to determine that applying a constant proportional to fuel consumption, as is known in the prior art, does not provide a relevant estimate of emissions. This system also makes it possible to identify in general that known methods of estimating CO2 overestimate the actual quantity emitted compared to that 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. The estimation methods also do not make it possible to measure the positive impact of adding rigid sails to the boat, which the system according to the invention makes possible.Furthermore, fuel consumption-based estimation methods also exhibit inaccuracies when the boat is stationary, due to unreliable fuel consumption measurements, particularly when using a Pitot tube for this purpose.

[0073] As stated above, the processing unit can render graphic content representative of the parameters listed above, preferably together with the third data, for example within a common graph.

[0074] Thus, by 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 a direct and continuous measurement of emissions, throughout the boat's journeys. Description of the figures

[0075] 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, in which:

[0076] [Fig.1]

[0077] Fig. 1 schematically illustrates a system for measuring the emissions of a gas circuit, according to a first embodiment of the present invention;

[0078] [Fig.2]

[0079] Fig. 2 schematically illustrates a system for measuring the emissions of a plurality of gas circuits, according to a second embodiment of the present invention;

[0080] [Fig.3]

[0081] [Fig.3] schematically illustrates a cabinet containing second means of measurement and a control unit of a system conforming to [Fig.1] or 2;

[0082] [Fig.4]

[0083] [Fig.4] schematically illustrates second means of measurement of a system conforming to [Fig.1] or 2;

[0084] [Fig.5]

[0085] [Fig.5] schematically illustrates a processing unit of a system conforming to [Fig.1] or 2;

[0086] [Fig.6]

[0087] [Fig.6] schematically illustrates a method for determining emission quantities from a gas circuit, implemented by a treatment unit conforming to [Fig.5];

[0088] [Fig.7]

[0089] [Fig.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 [Fig.1] or 2;

[0090] [Fig.8]

[0091] [Fig.8] illustrates a second graph representing a quantity of emissions measured by a system conforming to [Fig.1] or 2;

[0092] [Fig.9]

[0093] Figure [Fig. 9] illustrates a third graph representing an estimated quantity of emissions, according to prior art methods;

[0094] [Fig. 10]

[0095] Figure [Fig. 10] illustrates a fourth graph representing a fuel flow rate as a function of a boat's engine speed, measured by a system conforming to Figure [1] or 2;

[0096] [Fig.1 1]

[0097] 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

[0098] [Fig. 12]

[0099] 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. Detailed description

[0100] 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.

[0101] As indicated in the preamble to the description, current solutions for determining the emissions of a ship are based on estimates and remote spot measurements, resulting in a lack of reliability in measurement and details on the evolution of emissions during a journey.

[0102] 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.

[0103] 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.

[0104] It will be understood here 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 presenting fewer or as many constraints as boats.

[0105] Furthermore, emissions preferably include CO2 emissions, particularly in the context 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 a measurement may prove useful to a person skilled in the art, either in addition to or instead of a measurement of CO2 emissions.

[0106] 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 ship. 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 ship 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'.

[0107] The system 1, 1' thus comprises first measuring means 11, 11' for a flow rate associated with the gas circuit 10, 10'. The first measuring means 11, 11' comprise, for example, at least one Pitot probe, preferably two Pitot probes per gas circuit 10, 10'. The first measuring means 11, 11' are configured to measure a total flue gas 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 carried out continuously and / or at regular intervals. The first measuring means 11, 11' can thus be directly implemented on the circuit of gas 10, 10', and allow to determine a total quantity of fumes emitted by the boat.

[0108] 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.

[0109] By measuring circuit 13, 13', we mean a dedicated circuit, separate from the gas circuit 10, 10', on which measurements can be carried out in a controlled manner. The measuring circuit 13, 13' is thus supplied upstream by the gas circuit 10, 10', and terminates downstream at a separate outlet, for example, back on the gas circuit 10, 10'. In the present example, the outlet of the measuring circuit 13, 13' is of no particular importance, as the fumes produced by the boat are discharged into the outside atmosphere.

[0110] 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 measurements desired, 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'.

[0111] 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 especially 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.

[0112] Advantageously, directly downstream of the sampling means 12, 12', a multiplexer 16, 16' configured to connect a plurality of gas inlets to the same measurement circuit 13, 13' is provided.

[0113] Thus, in the example of [Fig. 2], the 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 comprising 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'.

[0114] According to the example in [Fig.1], the 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.

[0115] In these two examples, the use of multiplexers 16, 16' makes it possible to minimize the number of measurement circuits 13, 13', and therefore the associated means.

[0116] In each measurement circuit 13, 13', second measurement means 14, 14' for measuring emission concentrations are provided. These second measurement means 14, 14' are thus arranged downstream of the sampling means 12, 12' and the multiplexer 16, 16'. The second 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 second measurement means 14, 14' are provided, for example, arranged in series in the measurement circuit 13, 13'.

[0117] According to the example in Figures 3 and 4, the second measuring means 14, 14' define two parallel circuits 13a, 13b from the measuring circuit 13. An emission concentration sensor 141, for example the CO2 sensor above, is associated with the first circuit 13a. The flux between the two parallel circuits 13a, 13b can then be adjusted to ensure a reliable measurement by the emission concentration sensor 141.

[0118] A flow controller 142 is thus provided on the first circuit 13a, as well as two pressure controllers 143a, 143b associated with the parallel circuits 13a, 13b. The flow controller 142 is preferably placed upstream of the concentration sensor 141 and the first pressure controller 143a is placed downstream of the concentration sensor 141. The flow controller 142 thus allows the flow rate to be adjusted up to the concentration sensor 141, while the pressure controllers 143a, 143b allow the pressure in the two parallel circuits 13a, 13b to be adjusted.

[0119] 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 [Fig. 3]. In the example of [Fig. 2], the cabinet 100' comprises the plurality of measuring circuits 13, 13' and all associated elements, from the multiplexers 16, 16'.

[0120] In particular, in this same example, as well as in the example of [Fig. 1], the measuring circuit 13, 13' includes a gas conditioner 15, 15' located upstream of the second measuring 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 the gas in the measuring circuit 13, 13' to be regulated. The gas conditioner 15, 15' is, for example, configured to regulate the gas temperature, the circulation in the gas circuits 10, 10' corresponding to hot fumes that could damage the second measuring 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.Furthermore, conditioning the gas in the measuring circuits 13, 13' at a controlled temperature and / or pressure ensures accurate measurement and facilitates the calculations below.

[0121] Similarly, as illustrated in [Fig. 2], the system 1' advantageously includes purging means 19a, 19a', 19b, 19b'. For example, first purging means 19a, 19a' are provided, 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, and ensure 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.

[0122] As illustrated in Figures 1 and 5, the system 1, 1' further comprises a processing unit 2, which is configured for implementing a method for determining the quantity of emissions from the gas circuits 10, 10' of the vessel, for example, method 3 of [Fig. 6]. The processing unit 2 is, for example, configured 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 in the form of electronic circuits or software (or computer) modules, or a combination of electronic circuits and software modules.

[0123] 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 memory. and / or non-volatile and / or includes a memory storage device which may include volatile and / or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic or optical disk.

[0124] 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.

[0125] 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.

[0126] In a first step 31 of the emission determination process, the processing unit 2 receives first 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 first data and / or the second data are received, for example, by a beacon unit 22 of the processing unit 2.

[0127] In a first embodiment, the system 1,1' comprises a server located away from the boat, the server comprising the processing unit 2. In other words, the processing unit 2 is located away from the boat and receives the first and second data via a wireless link. As illustrated in [Fig. 1], the system 1,1' comprises, for example, data transmission means 17, destined for the server and the processing unit 2, corresponding to dedicated means for long-range communication.

[0128] In this same example, the 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, for example, into the cabinet 100, as shown in [Fig. 3]. The control unit 18 thus forms a gateway between the measuring means and the transmission means 17, and allows the data to be aggregated, time-stamped, etc., for transmission. Preferably, a Moxa ioThinx® type gateway forming the control unit 18 is provided, 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 type communication protocol.

[0129] According to another example, the transmission means 17 communicate independently with the first measuring means 11, 11' and the second measuring means 14, 14', that is, 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.

[0130] In a second embodiment, the system 1,1' comprises a central unit associated with the boat, i.e., a central unit directly onboard the boat, as opposed to a remote server, the central unit comprising 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 function, directly on the boat, without requiring long-range communication and in a completely independent manner.The central unit can also perform long-range communications separately, for example to transmit the results of process 3 to a remote server, for updates, etc.

[0131] Optionally, once the first and / or second data points have been received, the processing unit 2 performs data correction. This correction may involve, for example, eliminating erroneous data related to disturbances at the sensor level, in particular by removing data that is significantly different from its usual values, correcting instrument drift due to soiling and / or wear of the measuring means, or any other correction technique known to those skilled in the art. The processing unit 2 may also be configured to control the purge means 19a, 19a', 19b, 19b' based on detected disturbances, for example via a control circuit 23 integrated into the processing unit 2 and communicating with the purge means 19a, 19a', 19b, 19b'.

[0132] 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'. The third data points are, for example, determined at regular intervals so as to track the evolution of the quantity of emissions. For example, 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 suitable by those skilled in the art and relevant to the duration of a vessel's journey and the variability of the conditions. It is understood that since the measurements are carried out directly on the gas circuit 10, 10' on board, the data can be received continuously throughout a journey.

[0133] The processor can thus determine, for a given compound, for example for CO2, a volumetric flow rate FvCo2, from the following formula:

[0134] [Math.l] ^vCOl ~ Pytotal^PcOl

[0135] 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. FvCo2 and Fvtotai are, for example, expressed in m³ / h. Such a formula can be applied separately for each measured gas circuit 10, 10', or jointly for any gas circuit 10, 10' having the same CO2 concentration.

[0136] The ideal gas law can be applied to CO2 such that:

[0137] [Math.2] PV = nRT=^RT

[0138] 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.

[0139] Such a formula can be applied to link the volumetric flow rate FvCo2 to the mass flow rate FmCo2, replacing respectively the volume V and the mass m, so that:

[0140] [Math.3] Pm€O2 = ^vCO2^ CO^'^ Rt) = perfect

[0141] With Kperfect a constant which can be calculated for any ideal gas, of value 44.30 mol / m3, with a reference pressure P of 101.325 kPa, R equal to 8.314 Pa.m3.mol1 .K *, and a reference temperature of 273.15K.

[0142] Thus, the actual quantity of CO2 associated with the gas circuit 10, 10' can be obtained directly from the first and second data, via the formula:

[0143] [Math.4] Pmcm - ^vtotal^COl^COl''^-perfect

[0144] With FmCo2 the quantity of CO2 emitted via the gas circuit 10, 10' in gh*. This 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.

[0145] 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 from a concentration of the associated compound measured by the second measuring means 14, 14'. The processing unit 2 can thus determine a quantity of carbon dioxide emissions as well as a wide variety of other compounds.

[0146] The processing unit 2 can advantageously be configured to generate graphic content representative of the third data. The processing unit 2 communicates, for example, with a human-machine interface, via the beacon unit 22 or another dedicated unit, so as to allow the display of graphic content representative of the determined emission quantities.

[0147] In particular, system 1 may include third means for measuring boat parameters, with processing unit 2 receiving representative information about the parameters through communication with the third means, and the graphic content(s) being further generated based on these parameters. Processing unit 2 may also perform other additional calculations based on these parameters, depending on the type of analysis required. Generally, processing unit 2 allows for the centralization of data associated with boat emissions.

[0148] Such parameters include, for example: - the operation of a boat engine; - the boat's fuel consumption; - a boat trip; and - the navigation conditions of said boat.

[0149] The graphic content corresponds, for example, to one or more of the graphics illustrated in Figures 7 to 12.

[0150] Thus, the first graph 4 of [Fig.7] illustrates the evolution, over time 41, of a plurality of variables including: - a flow rate of 42 from the gas circuits 10, 10'; - a quantity of CO2 43 determined according to the process; - a fuel consumption of 44 for the boat; and - an engine speed of 45 for the boat.

[0151] The first graph 4 illustrates, in particular, that the flow rate 42 and the quantity of CO2 43 determined according to the process are correlated, suggesting that the CO2 concentration in the exhaust fumes is essentially constant. Conversely, the variations in fuel consumption 44 do not appear to be related to either the engine speed 45 or the quantity of CO2 43 emitted. Thus, 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.

[0152] The second graph 5 of [Fig. 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 of [Fig. 9] illustrates the evolution, over time 61, of the estimated quantity of CO2 62 (in t / h) from fuel consumption, as well as the evolution of engine speed 63 (in revolutions per minute).

[0153] Figure 5 and Figure 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 when the engine is stopped.

[0154] 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.

[0155] The fifth graph 8 of [Fig. 11] illustrates the evolution, over time 81, of a ratio 82 between the measured quantity of CO2 and the fuel consumed, as well as a favorable wind force 83, on a boat equipped with rigid sails. The ratio 82 is thus derived from the third set of data and a measurement of fuel consumption, while the favorable wind force 83 is derived from external sailing conditions (wind direction and intensity) and the boat's course. This fifth graph 8 shows that the ratio 82 varies over time and decreases when the ship's course follows the wind direction. System 1,1' thus makes it possible to monitor the effectiveness of measures aimed at reducing emissions.

[0156] Finally, the sixth graph 9 of [Fig. 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: - a quantity of CO2 92 (in t / h); - a quantity of CO 93 (in kg / h); - a quantity of NO 94 (in kg / h); - a quantity of NO2 95 (in kg / h); - a quantity of SO2 96 (in kg / h); and - a quantity of CH4 97 (in kg / h).

[0157] Thus, it will be understood that the present invention provides a system for measuring emissions from a ship's gas circuit, which makes it possible to quantify the emissions of a variety of compounds produced during a ship's journey, in particular CO2. This quantification is carried out using direct and continuous measurements, greatly increasing the accuracy of the measurements compared to known solutions of prior art. This increased precision makes it possible to better determine the impact, positive or negative, of navigation practices and emission reduction techniques.

[0158] It should be noted that this detailed description relates to a particular embodiment of the present invention, but in no way does this description limit the scope of the invention; on the contrary, its purpose is to remove any possible inaccuracy or misinterpretation of the following claims.

[0159] It should also be noted that the reference signs in parentheses in the following claims are in no way intended to be limiting; these signs are solely intended to improve the intelligibility and understanding of the following claims and the scope of the protection sought.

Claims

Demands

1. System (1) for measuring emissions from a gas circuit (10) of a ship, said system (1) comprising: - first means for measuring a flow rate (42) associated with said gas circuit (10); - sampling means (12) for said gas circuit (10), configured to connect said gas circuit (10) to a measuring circuit (13); - second means for measuring an emission concentration, associated with said measuring circuit (13), downstream of said sampling means (12); and - a processing unit (2), said processing unit (2) being configured to: - receive (31) first data representative of said flow rate (42), from said first means for measuring (11); - receive (32) second data representative of said emission concentration, from said second means for measuring (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) comprising 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, further comprising 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. System (1) according to any one of claims 1 to 13, which comprises 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 an emission quantity of each of said compounds by 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: - the operation of an engine (45, 53, 63, 71) of said boat; - the fuel consumption (44, 72) of said boat; - a route of said boat; and - the navigation conditions of said boat, said processing unit (2) being configured to receive information representative of said parameters, from said third means for measuring.

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