Exhaust gas treatment device

Abstract

An exhaust gas treatment device (3) is provided with: a sulfur adsorption unit (41) which is provided in an exhaust gas flow path (2) through which exhaust gas discharged from an engine (10) flows, and which adsorbs sulfur-containing substances in the exhaust gas; a heater (51) capable of heating the exhaust gas flowing into the sulfur adsorption unit (41); a heater bypass flow path (71) that is provided in the exhaust flow path (2) and bypasses the heater (51) and the sulfur adsorption unit (41); and a control unit (30) that heats a portion of the exhaust gas by the heater (51) and causes the exhaust gas to flow into the sulfur adsorption unit (41) during regeneration of the sulfur adsorption unit (41), and causes the remainder of the exhaust gas to flow into the heater bypass flow path (71). During regeneration of the sulfur adsorption unit (41), in a flow path in which the portion of the exhaust gas flows, the portion of the exhaust gas passing through the sulfur adsorption unit (41) is mixed with the remaining portion of the exhaust gas passing through the heater bypass flow path (71) at a mixing position (P12) on the downstream side of the sulfur adsorption unit (41). As a result, an inexpensive material can be used downstream from the mixing position (P12).

Description

TECHNICAL FIELD

[0001] The present application relates to an exhaust treatment device.

[0002] [REFERENCE TO RELATED APPLICATIONS]

[0003] This application claims the benefit of priority of Japanese Patent Application No. JP 2023-56340 filed on March 30, 2023, the disclosure of which is incorporated herein in its entirety. BACKGROUND

[0004] In recent years, the movement to switch the fuel of a ship from heavy oil to liquefied natural gas (LNG: liquefied natural gas) is accelerating. In an LNG-fueled LNG-fueled ship, methane slip in which a part of methane in the LNG fuel is directly discharged in an unburned state from the engine outlet becomes a problem. Therefore, it is being studied to configure a methane oxidation catalyst in an exhaust flow path through which exhaust gas of the engine flows, and to oxidize methane on the catalyst to reduce methane slip.

[0005] On the other hand, sulfur components contained in lubricating oil and the like inside the engine are mixed in the exhaust gas of the engine, and therefore a substance containing sulfur is sometimes adsorbed to the methane oxidation catalyst. Due to this, the catalytic activity of the methane oxidation catalyst decreases, that is, the methane oxidation catalyst is subjected to sulfur poisoning. In the case where sulfur poisoning occurs, a gas at a high temperature is supplied to the methane oxidation catalyst, and a regeneration process such as desorption of sulfur from the surface of the methane oxidation catalyst is performed.

[0006] Further, in Japanese Patent Application Publication No. 2009-185620, an exhaust purification device of an internal combustion engine is disclosed in which an NSR catalyst is configured in an exhaust passage, and a bypass passage that bypasses the NSR catalyst is also provided. In sulfur regeneration in which fuel is added to exhaust gas at a position more upstream than the NSR catalyst and the exhaust gas is made rich or stoichiometric so as to release sulfur components from the NSR catalyst, the exhaust gas flow rate flowing into the NSR catalyst is changed in order of low flow rate, medium flow rate, and high flow rate using a bypass valve of the bypass passage. In Japanese Patent Application Publication No. 2016-163874, a catalyst for removing methane oxidation is described that is obtained by impregnating an aqueous nitric acid solution in which both iridium nitrate and dinitrodiammineplatinum are dissolved in a zirconia carrier, and then performing calcination. In Japanese Patent Application Publication No. 2009-185763, a sulfur oxide adsorbent is disclosed in which adsorbed sulfur oxides are detached when placed in a heated atmosphere.

[0007] However, in the regeneration of the methane oxidation catalyst, it is considered to supply a high-temperature gas to the methane oxidation catalyst by heating the exhaust gas with a heater, but in this case, not only in the vicinity of the methane oxidation catalyst but also from the methane oxidation catalyst to the piping and the like on the downstream side, a high-priced material having excellent heat resistance is required. As a result, the manufacturing cost of the exhaust gas processing device increases. In the exhaust gas processing device in which a sulfur adsorbent that adsorbs sulfur (a substance containing sulfur) is provided on the upstream side of various catalysts to suppress the sulfur poisoning of the catalyst, in the case where a high-temperature gas is supplied to the sulfur adsorbent by heating the exhaust gas with a heater, similarly, the manufacturing cost of the exhaust gas processing device increases. Therefore, a method of reducing the manufacturing cost of the exhaust gas processing device having a sulfur adsorption section (methane oxidation catalyst, sulfur adsorbent, and the like) that adsorbs sulfur in the exhaust gas is required SUMMARY

[0008] (I) PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] An object of the present application is to reduce the manufacturing cost of an exhaust gas processing device.

[0010] (II) SOLUTION TO THE PROBLEM

[0011] Mode 1 of the present application is an exhaust gas processing device including: a sulfur adsorption section provided in an exhaust gas flow path through which exhaust gas discharged from an engine flows, which adsorbs a substance containing sulfur in the exhaust gas; a heater that can heat the exhaust gas flowing into the sulfur adsorption section; a heater bypass flow path provided in the exhaust gas flow path, which bypasses the heater and the sulfur adsorption section; and a control section that, at the time of regeneration of the sulfur adsorption section, heats a part of the exhaust gas with the heater and causes it to flow into the sulfur adsorption section, and causes the remaining part of the exhaust gas to flow into the heater bypass flow path, and at the time of regeneration of the sulfur adsorption section, in a flow path through which the part of the exhaust gas flows, at a mixing position on the downstream side of the sulfur adsorption section, the part of the exhaust gas that has passed through the sulfur adsorption section and the remaining part of the exhaust gas that has passed through the heater bypass flow path are mixed.

[0012] According to the present application, it is possible to reduce the temperature of the gas flowing on the downstream side from the mixing position at the time of regeneration of the sulfur adsorption section, and it is possible to use a low-priced material on the downstream side from the mixing position. As a result, it is possible to reduce the manufacturing cost of the exhaust gas processing device.

[0013] Mode 2 of the present application is the exhaust gas processing device of Mode 1, in which the temperature of the exhaust gas flowing into the sulfur adsorption section at the time of regeneration of the sulfur adsorption section is 500°C or higher.

[0014] Mode 3 of the present application is the exhaust treatment device of Mode 1 (may also be Mode 1 or 2), in which the temperature of the mixed exhaust gas at the mixing location is 450°C or lower.

[0015] Mode 4 of the present application is the exhaust treatment device of Mode 1 (may also be any one of Modes 1 to 3), in which the engine uses a gas containing methane as fuel, the exhaust treatment device further comprises a methane oxidation catalyst disposed in the exhaust flow path on the downstream side of the sulfur adsorption section, which oxidizes methane contained in the exhaust gas, and the mixing location is immediately after the sulfur adsorption section or immediately after the methane oxidation catalyst.

[0016] Mode 5 of the present application is the exhaust treatment device of Mode 1 (may also be any one of Modes 1 to 3), in which the engine uses a gas containing methane as fuel, a methane oxidation catalyst is disposed in the exhaust flow path, which oxidizes methane contained in the exhaust gas and adsorbs sulfur-containing substances in the exhaust gas, thereby also functioning as the sulfur adsorption section, and the mixing location is immediately after the methane oxidation catalyst.

[0017] Mode 6 of the present application is the exhaust treatment device of Mode 4 or 5, further comprising a methane concentration measurement section disposed in the exhaust flow path on the downstream side of the methane oxidation catalyst, which measures the methane concentration of the exhaust gas, and the control section determines the execution of the regeneration of the sulfur adsorption section based on the measurement value of the methane concentration measurement section.

[0018] Mode 7 of the present application is the exhaust treatment device of any one of Modes 1 to 5 (may also be any one of Modes 1 to 6), further comprising a temperature measurement section disposed on the downstream side of the mixing location, which measures the temperature of the exhaust gas, and the control section adjusts the flow ratio of the portion of the exhaust gas to the remaining portion of the exhaust gas based on the measurement value of the temperature measurement section.

[0019] Mode 8 of the present application is the exhaust treatment device of any one of Modes 1 to 5 (may also be any one of Modes 1 to 7), further comprising a sulfur concentration measurement section disposed in the exhaust flow path on the downstream side of the sulfur adsorption section, which measures the sulfur concentration of the exhaust gas, and the control section determines the execution of the regeneration of the sulfur adsorption section or / and the end of the regeneration of the sulfur adsorption section based on the measurement value of the sulfur concentration measurement section.

[0020] Mode 9 of the present application is the exhaust treatment device of any one of Modes 1 to 5 (may also be any one of Modes 1 to 8), in which a turbine of a turbocharger is disposed in the exhaust flow path, and the exhaust gas taken out from between the engine and the turbine in the exhaust flow path is heated by the heater at the time of the regeneration of the sulfur adsorption section.

[0021] The above objects and other objects, features, aspects and advantages of the present application will become more apparent from the following detailed description of the present application when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a view showing the structure of an engine system of a first embodiment.

[0023] Figure 2 is a sectional view showing a reaction vessel.

[0024] Figure 3 is a view for explaining a regeneration operation in an exhaust treatment device.

[0025] Figure 4 is a view showing the structure of an exhaust treatment device of a second embodiment.

[0026] Figure 5 is a view for explaining a regeneration operation in an exhaust treatment device.

[0027] Figure 6 is a view for explaining an additional regeneration operation in an exhaust treatment device.

[0028] Figure 7 is a view showing the structure of an exhaust treatment device of a third embodiment.

[0029] Figure 8 is a view for explaining a regeneration operation in an exhaust treatment device.

[0030] Figure 9 is a view showing the structure of an exhaust treatment device of a fourth embodiment.

[0031] Figure 10 is a view for explaining a regeneration operation in an exhaust treatment device.

[0032] Figure 11 is a view for explaining an additional regeneration operation in an exhaust treatment device.

[0033] Figure 12 is a view showing the structure of an exhaust treatment device of a fifth embodiment.

[0034] Figure 13 is a view for explaining a regeneration operation in an exhaust treatment device.

[0035] Figure 14 is a view showing the structure of an exhaust treatment device of a sixth embodiment.

[0036] Figure 15 is a view for explaining a regeneration operation in an exhaust treatment device.

[0037] Figure 16 is a view for explaining additional regeneration operation in the exhaust treatment device.

[0038] Figure 17 is a view showing another example of the exhaust treatment device.

[0039] Figure 18 is a view showing another example of the exhaust treatment device. DETAILED DESCRIPTION

[0040] (First Embodiment)

[0041] Figure 1 is a view showing the structure of an engine system 1 of the first embodiment of the present application. The engine system 1 is mounted on, for example, a ship. The engine system 1 is provided with an engine 10, a turbocharger 16, and an exhaust treatment device 3. The engine 10 is a gas engine that uses a gas containing methane (CH4) as fuel, and in one example, the fuel is LNG (liquefied natural gas). The engine 10 can also use a fuel other than LNG. The engine 10 is, for example, a four-stroke engine. The engine 10 can also be a two-stroke engine or the like.

[0042] The engine 10 is provided with a plurality of cylinders 11 and an exhaust manifold 12. A piston is provided in each cylinder 11, and a space surrounded by the cylinder 11, the piston, and the like becomes a combustion chamber for combusting fuel. The turbocharger 16 is a supercharger provided with a turbine 161 and a compressor 162. In the turbocharger 16, the turbine 161 is rotated by exhaust gas described later. The compressor 162 compresses intake air (air) taken in from the outside of the engine 10 using the rotational force generated by the turbine 161, and pressurizes the intake air. The pressurized air is supplied to the combustion chamber of each cylinder 11, and is used for combustion of fuel. The plurality of cylinders 11 are connected to one exhaust manifold 12. Exhaust gas discharged from the plurality of combustion chambers is collected in the exhaust manifold 12. The exhaust gas discharged from the exhaust manifold 12 flows along an exhaust flow path 2 described later. The turbine 161 described above is provided in the exhaust flow path 2, and is rotated by exhaust gas.

[0043] The exhaust treatment device 3 is provided in the exhaust flow path 2. The exhaust flow path 2 is a flow path through which exhaust gas discharged from the engine 10 flows in normal operation described later. In the exhaust flow path 2, the exhaust treatment device 3 is provided. Figure 1 In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. In the exhaust flow path 2, the exhaust treatment device 3 is provided. 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[0044] The exhaust treatment device 3 has a control section 30, a sulfur adsorption section 41, a catalytic section 42, a gas temperature switching section 5, a flow path switching section 6, a heater bypass flow path 71, a catalyst bypass flow path 76, and a measurement unit 31. The control section 30 undertakes overall control of the exhaust treatment device 3. The control section 30 can also serve as a control section of the engine 10. The control section 30 is realized, for example, by a computer having a CPU, a memory, and the like executing a prescribed program. Part or all of the control section 30 can also be realized by a programmable logic controller (PLC) or the like.

[0045] The gas temperature switching section 5 has a heater 51. The heater 51 is provided to the exhaust flow path 2 and heats the exhaust gas. The heater 51 is, for example, an electric heater, a heat medium heater, or the like, and typically heats the exhaust gas without mixing other substances such as fuel in the exhaust gas. As described later, the heater 51 is provided on the upstream side of the sulfur adsorption section 41, and the exhaust gas that has passed through the heater 51 flows into the sulfur adsorption section 41. The gas temperature switching section 5 switches ON / OFF of the heater 51, whereby it is possible to switch between a normal gas inflow state and a high-temperature gas inflow state. In the normal gas inflow state, exhaust gas of a normal temperature (for example, 350 to 450°C) that has not been heated by the heater 51 flows to the sulfur adsorption section 41. In the high-temperature gas inflow state, exhaust gas of a higher temperature than the normal temperature that has been heated by the heater 51 flows to the sulfur adsorption section 41.

[0046] The sulfur adsorption section 41 is provided to the exhaust flow path 2. The sulfur adsorption section 41 contains a sulfur adsorbent that adsorbs a sulfur-containing substance (for example, a sulfur oxide or the like, hereinafter referred to as "sulfur-containing substance") in the exhaust gas. In the sulfur adsorbent, the adsorption capacity of the sulfur-containing substance in the sulfur adsorbent decreases when a certain amount of the sulfur-containing substance is adsorbed. In the regeneration operation described later, when the high-temperature gas inflow state is formed by the gas temperature switching section 5 and the surroundings of the sulfur adsorption section 41 become high-temperature, the sulfur-containing substance adsorbed to the sulfur adsorbent is desorbed. Thus, the adsorption capacity of the sulfur-containing substance in the sulfur adsorbent is regenerated. The temperature region in which the sulfur-containing substance is adsorbed to the sulfur adsorbent and the temperature region in which the sulfur-containing substance is desorbed from the sulfur adsorbent can be changed by the material selected as the sulfur adsorbent.

[0047] The catalytic section 42 is provided to the exhaust flow path 2 and oxidizes or reduces a prescribed substance in the exhaust gas. Figure 1The catalytic section 42 has a methane oxidation catalyst 421, a urea water supply section 429, and an SCR catalyst 422. The methane oxidation catalyst 421 is an example of a hydrocarbon decomposition catalyst, and oxidizes methane contained in the exhaust gas. As the methane oxidation catalyst 421, various materials are known, and a material corresponding to the conditions such as the temperature of the exhaust gas is appropriately selected and used. The urea water supply section 429 supplies urea water to the exhaust gas. The SCR catalyst 422 causes ammonia generated by thermal decomposition of urea to react with nitrogen oxides (NOx) contained in the exhaust gas, and converts them into nitrogen (N2) and water (H2O). As the SCR catalyst 422, various materials are known, and a material corresponding to the conditions such as the temperature of the exhaust gas is appropriately selected and used. In the catalytic section 42, a reducing agent other than urea can also be used.

[0048] In the exhaust gas flow path 2, the heater 51, the sulfur adsorption section 41, the methane oxidation catalyst 421, the urea water supply section 429, and the SCR catalyst 422 are arranged in this order from the upstream side toward the downstream side (i.e., from the exhaust manifold 12 side toward the exhaust port to the atmosphere). In the normal operation of the exhaust treatment device 3, the exhaust gas discharged from the engine 10 passes through the heater 51, the sulfur adsorption section 41, the methane oxidation catalyst 421, the urea water supply section 429, and the SCR catalyst 422 in this order. In the exhaust gas flow path 2, the heater 51, the sulfur adsorption section 41, the methane oxidation catalyst 421, the urea water supply section 429, and the SCR catalyst 422 are arranged in this order from the upstream side toward the downstream side (i.e., from the exhaust manifold 12 side toward the exhaust port to the atmosphere). In the normal operation of the exhaust treatment device 3, the exhaust gas discharged from the engine 10 passes through the heater 51, the sulfur adsorption section 41, the methane oxidation catalyst 421, the urea water supply section 429, and the SCR catalyst 422 in this order. In the exhaust gas flow path 2, the heater 51, the sulfur adsorption section 41, the methane oxidation catalyst 421, the urea water supply section 429, and the SCR catalyst 422 are arranged in this order from the upstream side toward the downstream side (i.e., from the exhaust manifold 12 side toward the exhaust port to the atmosphere). In the normal operation of the exhaust treatment device 3, the exhaust gas discharged from the engine 10 passes through the heater 51, the sulfur adsorption section 41, the methane oxidation catalyst 421, the urea water supply section 429, and the SCR catalyst 422 in this order. Figure 1 In the example of FIG. 6, the heater 51, the sulfur adsorption section 41, and the methane oxidation catalyst 421 are housed in one reaction container 40.

[0049] Figure 2 is a cross-sectional view of the reaction container 40. The reaction container 40 is, for example, a container whose inside is closed except for connection portions to the exhaust gas flow path 2. In the example of FIG. 6, the reaction container 40 is a cylindrical, square cross-sectional rectangular parallelepiped or a rectangular cross-sectional rectangular parallelepiped that extends in the direction of the exhaust gas flow path 2, and has a flow inlet 401 at one end portion in the direction and a flow outlet 402 at the other end portion. The flow inlet 401 and the flow outlet 402 are connection portions to the exhaust gas flow path 2. The exhaust gas that has passed through the turbine 161 of the turbocharger 16 flows into the reaction container 40 from the flow inlet 401, passes through the heater 51, the sulfur adsorption section 41, and the methane oxidation catalyst 421 in this order, and is discharged to the outside of the reaction container 40 from the flow outlet 402. Figure 2 Figure 1

[0050] ​​The flow path area inside the reaction vessel 40 (i.e., the cross-sectional area inside the reaction vessel 40 perpendicular to the exhaust flow direction) is sufficiently larger than the flow path area of ​​the exhaust flow path 2. Inside the reaction vessel 40, the exhaust flow velocity decreases, enabling efficient heating of the exhaust by the heater 51, adsorption of sulfur-containing substances in the sulfur adsorption section 41, and oxidation of methane by the methane oxidation catalyst 421. Furthermore, the pressure loss in the heater 51, sulfur adsorption section 41, and methane oxidation catalyst 421 is also reduced. An auxiliary heater can also be installed opposite the heater 51 to heat the reaction vessel 40 from the outside. The heater 51, sulfur adsorption section 41, and methane oxidation catalyst 421 can also be maintained... Figure 1 They are arranged in order and stored in separate containers.

[0051] like Figure 1 As shown, the heater bypass flow path 71 is provided in the exhaust flow path 2, bypassing the heater 51, the sulfur adsorption section 41, and the methane oxidation catalyst 421. One end of the heater bypass flow path 71 is connected to the connection point P11 between the turbine 161 and the heater 51 in the exhaust flow path 2. The other end of the heater bypass flow path 71 is connected to the connection point P12 between the methane oxidation catalyst 421 and the urea water supply section 429 in the exhaust flow path 2. A valve 211 is provided in the heater bypass flow path 71. The valve 211 is, for example, a flow regulating valve, and the control unit 30 adjusts the opening of the valve 211, thereby adjusting the flow rate of the exhaust gas flowing in the heater bypass flow path 71. In the exhaust flow path 2, a valve 212 is provided between the connection point P11 and the heater 51, and a valve 213 is provided between the methane oxidation catalyst 421 and the connection point P12. The control unit 30 controls the opening and closing of valves 212 and 213.

[0052] The catalyst bypass flow path 76 is provided in the exhaust flow path 2 to bypass the urea water supply unit 429 and the SCR catalyst 422. One end of the catalyst bypass flow path 76 is connected to the connection point P13 between the connection point P12 and the urea water supply unit 429 in the exhaust flow path 2. The other end of the catalyst bypass flow path 76 is connected to the connection point P14 downstream of the SCR catalyst 422 in the exhaust flow path 2. The connection point P14 is the position between the SCR catalyst 422 and the measurement position of the measurement unit 31 described later.

[0053] The flow path switching section 6 has a plurality of valves 61, 62, 63. The valve 61 is provided to the catalyst bypass flow path 76. The valve 62, the valve 63 are provided to the exhaust flow path 2. In detail, the valve 62 is arranged between the connection position P13 and the urea water supply section 429, the valve 63 is arranged between the SCR catalyst 422 and the connection position P14. The flow path switching section 6 opens the valve 61 and closes the valves 62, 63, thereby becoming a bypass state in which the exhaust gas flows in the catalyst bypass flow path 76 without flowing in the urea water supply section 429 and the SCR catalyst 422. In addition, the valve 61 is closed and the valves 62, 63 are opened, thereby becoming a non-bypass state in which the exhaust gas flows in the urea water supply section 429 and the SCR catalyst 422 without flowing in the catalyst bypass flow path 76. In this way, in the flow path switching section 6, the bypass state and the non-bypass state can be switched.

[0054] The measurement unit 31 measures the state of the exhaust gas on the downstream side of the connection position P14 in the exhaust flow path 2. At the time of operation of the exhaust treatment device 3, the exhaust gas always passes through the measurement position of the measurement unit 31. The measurement unit 31 measures the temperature of the exhaust gas. The measurement unit 31 measures the concentration of methane in the exhaust gas. The measurement unit 31 measures the concentration of sulfur in the exhaust gas. The measurement unit 31 outputs the measurement values of the temperature, the concentration of methane, and the concentration of sulfur to the control section 30. In the measurement unit 31, only one or two of the temperature measurement section 311, the methane concentration measurement section 312, and the sulfur concentration measurement section 313 can be provided. Figure 1 In the exhaust treatment device 3, the measurement unit 31 has a temperature measurement section 311, a methane concentration measurement section 312, and a sulfur concentration measurement section 313. The temperature measurement section 311 measures the temperature of the exhaust gas. The methane concentration measurement section 312 measures the concentration of methane in the exhaust gas. The sulfur concentration measurement section 313 measures the concentration of sulfur in the exhaust gas. The temperature measurement section 311, the methane concentration measurement section 312, and the sulfur concentration measurement section 313 can each be used with a commercially available product. The measurement values of the temperature measurement section 311, the methane concentration measurement section 312, and the sulfur concentration measurement section 313 are each output to the control section 30. In the measurement unit 31, only one or two of the temperature measurement section 311, the methane concentration measurement section 312, and the sulfur concentration measurement section 313 can be provided.

[0055] In the normal operation of the exhaust treatment device 3, the valves 211, 61 are closed and the other valves 212, 213, 62, 63 are opened, thereby the exhaust gas flows along the exhaust flow path 2. At this time, the heater 51 is in an OFF state, and heating of the exhaust gas is not performed. That is, the gas temperature switching section 5 is in a normal gas inflow state in which the exhaust gas at a normal temperature flows into the sulfur adsorption section 41. The sulfur-containing substance contained in the exhaust gas is adsorbed to the sulfur adsorption section 41. Thereby, the sulfur poisoning (sulfur-induced degradation) of the methane oxidation catalyst 421 and the SCR catalyst 422 arranged on the downstream side of the sulfur adsorption section 41 can be suppressed. In addition, the methane contained in the exhaust gas is oxidized by the methane oxidation catalyst 421. The flow path switching section 6 is in a non-bypass state in which the exhaust gas flows in the urea water supply section 429 and the SCR catalyst 422 without flowing in the catalyst bypass flow path 76. In the SCR catalyst 422, the nitrogen oxides contained in the exhaust gas are reduced.

[0056] In the sulfur concentration measuring section 313, the sulfur concentration in the exhaust gas is measured at all times. When the measured value of the sulfur concentration measured by the sulfur concentration measuring section 313 is the prescribed regeneration execution threshold value, it is determined by the control section 30 that the sulfur adsorption ability of the sulfur-containing substance in the sulfur adsorbent of the sulfur adsorption section 41 has decreased. Thus, the regeneration operation of regenerating the sulfur adsorption section 41 is executed. In this way, in the control section 30, the execution of the regeneration of the sulfur adsorption section 41 is determined based on the measured value of the sulfur concentration measuring section 313.

[0057] Figure 3 is a view for explaining the regeneration operation in the exhaust treatment device 3, and the flow path of the exhaust gas flow is indicated by a thick dashed line and a single-dot chain line (the same in other views for explaining the regeneration operation and the additional regeneration operation described later). In addition, in Figure 3 , the illustration of the control section 30 is omitted (the same in Figures 4 to 18 described later). At the start of the regeneration operation, the valve 211 of the heater bypass flow path 71 is gradually opened by the control section 30. In addition, the gas temperature switching section 5 switches the heater 51 to the ON state, thereby switching from the normal gas inflow state to the high-temperature gas inflow state. In Figure 3 , the outer edge of the block of the heater 51 is indicated by a thick line, thereby indicating that the heater 51 is in the ON state (the same in other views indicating the exhaust treatment device).

[0058] At the connection position P11, a part of the exhaust gas flows toward the heater 51, is heated by the heater 51, and flows into the sulfur adsorption section 41 (refer to the thick dashed line in Figure 3 ). Thus, the surroundings of the sulfur adsorption section 41 become high-temperature, and the sulfur-containing substance adsorbed to the sulfur adsorption section 41 is desorbed. In the regeneration operation, the temperature of the exhaust gas flowing into the sulfur adsorption section 41 is, for example, 500°C or higher, preferably 550°C or higher, and more preferably 580°C or higher. Since the high-temperature exhaust gas flows in the flow path from the heater 51 to the connection position P12, this flow path is formed of a material having a high heat resistance temperature, such as stainless steel. The upper limit of the temperature of the exhaust gas flowing into the sulfur adsorption section 41 is the upper limit of the heat resistance temperature of the material for this flow path. The exhaust gas containing the sulfur-containing substance desorbed from the sulfur adsorption section 41 flows toward the connection position P12 through the methane oxidation catalyst 421. At this time, since the exhaust gas is high-temperature, the sulfur-containing substance adsorbed to the methane oxidation catalyst 421 is also desorbed.

[0059] At the connection position P11, the remaining part of the exhaust gas flows into the heater bypass flow path 71 and flows toward the connection position P12 (refer to Figure 3The exhaust gas that passed through the heater 51, the sulfur adsorption section 41, and the methane oxidation catalyst 421 mixes with the exhaust gas that passed through the heater bypass flow path 71 at the connection position P12. Thus, the connection position P12 is a mixing position at which the high-temperature exhaust gas that passed through the heater 51 mixes with the normal-temperature exhaust gas that did not pass through the heater 51. In the present embodiment, the connection position P12 will also be referred to as the "mixing position P12" hereinafter.

[0060] The mixing position P12 in the exhaust gas flow path 2 is immediately after the methane oxidation catalyst 421. Here, "the mixing position P12 is immediately after the methane oxidation catalyst" means that no structure (catalyst, heater, or the like) that changes the state of the exhaust gas in terms of composition, temperature, or the like is provided between the methane oxidation catalyst 421 and the mixing position P12. The distance of the flow path between the methane oxidation catalyst 421 and the mixing position P12 is preferably shorter than the heater bypass flow path 71. The distance can also be longer than the length of the heater bypass flow path 71. The temperature of the mixed exhaust gas at the mixing position P12 is below a prescribed limit temperature. The limit temperature is lower than the temperature of the exhaust gas that passed through the heater 51, and is, for example, 450°C, and is preferably 430°C. Thus, a low-cost material (for example, carbon steel or the like) having a relatively low heat resistance temperature can be used for the flow path downstream of the mixing position P12.

[0061] In the exhaust gas processing device 3, the temperature of the exhaust gas is measured by the temperature measuring section 311 at all times. The measured value of the temperature measured by the temperature measuring section 311 is the temperature of the mixed exhaust gas at the mixing position P12. In the control section 30, the opening degree of the valve 211 of the heater bypass flow path 71 is controlled on the basis of the measured value so that the measured value of the temperature measuring section 311 becomes below the limit temperature. For example, a set temperature lower than the limit temperature is set in advance, and the opening degree of the valve 211 of the heater bypass flow path 71 is increased in the case where the measured value of the temperature measuring section 311 is higher than the set temperature. In the case where the measured value is lower than the set temperature, the opening degree of the valve 211 is decreased. Thus, in the control section 30, the ratio of the flow rate of the exhaust gas that flows into the heater 51 from the connection position P11 to the flow rate of the exhaust gas that flows into the heater bypass flow path 71 from the connection position P11 (that is, the mixing ratio at the mixing position P12) is adjusted on the basis of the measured value of the temperature measuring section 311. Thus, the temperature of the mixed exhaust gas at the mixing position P12 is substantially constant at the set temperature.

[0062] In the case where the flow rate, temperature, or the like of the exhaust gas discharged from the engine 10 is substantially constant, the opening degree of the valve 211 can also be constant during the regeneration operation. According to the design of the exhaust gas flow path 2, the valve 211 can also be fully opened during the regeneration operation, and the opening degree of the control valve 212 or the valve 213 can be controlled, whereby the mixing ratio at the mixing position P12 is adjusted.

[0063] Further, in the regeneration operation, the flow path switching section 6 opens the valve 61 and closes the valve 62 and the valve 63 by the control of the control section 30. Thereby, the bypass state in which the exhaust gas does not flow in the urea water supply section 429 and the SCR catalyst 422 but flows in the catalyst bypass flow path 76 is formed. Here, the mixed exhaust gas at the mixing position P12 contains high concentration of sulfur-containing substances. Assuming that this exhaust gas flows in the SCR catalyst 422, the deposition of ammonium bisulfate (NH4HSO4), ammonium sulfate ((NH4)2SO4) is generated on the SCR catalyst 422. As a result, the catalytic activity of the SCR catalyst 422 is reduced, that is, the SCR catalyst 422 is subjected to sulfur poisoning.

[0064] In fact, in the exhaust gas treatment device 3 according to the present embodiment, Figure 3 In the exhaust gas treatment device 3, the bypass state in which the exhaust gas does not flow in the urea water supply section 429 and the SCR catalyst 422 but flows in the catalyst bypass flow path 76 is formed in the flow path switching section 6. Thereby, the sulfur poisoning of the SCR catalyst 422 generated in the case where the exhaust gas containing high concentration of sulfur-containing substances flows in the SCR catalyst 422 is prevented. In the exhaust gas treatment device 3, the SCR catalyst 422 is a catalyst which is a target of prevention of sulfur poisoning in the regeneration operation (i.e., a target catalyst). In the exhaust gas treatment device 3, the case where the sintering due to heat is generated in the SCR catalyst 422, the fine pores are clogged to cause the performance reduction is also suppressed.

[0065] The exhaust gas containing sulfur-containing substances is discharged to the atmosphere. In the case where there is a limit to the sulfur concentration of the exhaust gas to be discharged to the atmosphere, it is preferable to control the opening degree of the valve 211 of the heater bypass flow path 71 based on the measured value of the sulfur concentration measuring section 313. In this case, the mixing ratio at the mixing position P12 is adjusted so that the measured value of the temperature measuring section 311 is maintained to be lower than the limit temperature and the measured value of the sulfur concentration measuring section 313 (i.e., the sulfur concentration of the exhaust gas to be discharged to the atmosphere) is lower than the limit value.

[0066] When the measured value of the sulfur concentration measuring section 313 becomes lower than a predetermined regeneration end threshold value, it is determined by the control section 30 that the adsorption ability of the sulfur-containing substances in the sulfur adsorbent of the sulfur adsorption section 41 is recovered. Thus, in the control section 30, the end of the regeneration of the sulfur adsorption section 41 is determined based on the measured value of the sulfur concentration measuring section 313. Thereafter, the valve 211 of the heater bypass flow path 71 is gradually closed. Further, the gas temperature switching section 5 makes the heater 51 to be in the OFF state, thereby switching from the high-temperature gas inflow state to the normal gas inflow state. Also, the flow path switching section 6 closes the valve 61 and opens the valve 62 and the valve 63, thereby forming the non-bypass state in which the exhaust gas does not flow in the catalyst bypass flow path 76 but flows in the urea water supply section 429 and the SCR catalyst 422. Thereby, the regeneration operation in the exhaust gas treatment device 3 is ended and the normal operation is started again.

[0067] The execution of the regeneration of the sulfur adsorption section 41 can also be determined based on the measured value of the methane concentration of the methane concentration measuring section 312. In this case, for example, the methane removal rate in the methane oxidation catalyst 421 is calculated. Specifically, a test or the like is performed in advance, and thereby a relationship between the load of the engine 10 and the methane concentration of the exhaust gas discharged from the engine 10 at the load (for example, a table that maps the methane concentration to the load) is obtained. Further, in a case where master data indicating the above-described relationship is prepared in the same type of engine, the master data can also be utilized.

[0068] In the control section 30, the methane concentration of the exhaust gas flowing into the exhaust flow path 2, that is, the methane concentration at the inlet of the exhaust treatment device 3 is determined in accordance with the current load of the engine 10. In the methane concentration measuring section 312, the methane concentration in the exhaust gas that has passed through the methane oxidation catalyst 421, that is, the methane concentration at the outlet of the exhaust treatment device 3 is measured at all times. In the control section 30, for example, the proportion of the methane concentration at the inlet of the exhaust treatment device 3 to the methane concentration obtained by subtracting the outlet from the inlet is calculated as the methane removal rate. When the methane removal rate becomes equal to or lower than a prescribed threshold value, it is determined by the control section 30 that the catalytic activity of the methane oxidation catalyst 421 is reduced, and the regeneration operation is executed. The reduction in the catalytic activity of the methane oxidation catalyst 421 is caused by the occurrence of sulfur poisoning in the methane oxidation catalyst 421 due to the reduction in the adsorption capacity of the sulfur-containing substance in the sulfur adsorption section 41. The end of the regeneration of the sulfur adsorption section 41 can be determined based on the measured value of the sulfur concentration measuring section 313, or can be determined in accordance with the execution time (duration) of the regeneration operation or the like.

[0069] In addition, the execution of the regeneration of the sulfur adsorption section 41 can also be determined by the cumulative time during which the exhaust treatment device 3 continues the normal operation, that is, the cumulative time during which the exhaust gas passes through the sulfur adsorption section 41 without the regeneration operation being performed. The cumulative time during which the regeneration of the sulfur adsorption section 41 should be performed is determined in advance from past operation data, a test, or the like.

[0070] As described above, one viewpoint of the present embodiment is that the execution of the regeneration of the sulfur adsorption section 41 is determined based on the methane concentration of the exhaust gas flowing into the exhaust flow path 2. Figure 1The exhaust treatment device 3 of the application has a sulfur adsorption section 41 provided in the exhaust flow path 2, which adsorbs a sulfur-containing substance in the exhaust gas; a heater 51, which can heat the exhaust gas flowing into the sulfur adsorption section 41; a heater bypass flow path 71, which bypasses the heater 51 and the sulfur adsorption section 41; and a control section 30, which, at the time of regeneration of the sulfur adsorption section 41, heats a portion of the exhaust gas using the heater 51 and causes it to flow into the sulfur adsorption section 41, and causes the remaining portion of the exhaust gas to flow into the heater bypass flow path 71. At the time of regeneration of the sulfur adsorption section 41, in the flow path in which the portion of the exhaust gas flows, at a mixing position P12 on the downstream side of the sulfur adsorption section 41, the portion of the exhaust gas that has passed through the sulfur adsorption section 41 and the remaining portion of the exhaust gas that has passed through the heater bypass flow path 71 are mixed. Thus, the temperature of the gas flowing on the downstream side from the mixing position P12 at the time of regeneration of the sulfur adsorption section 41 can be reduced, and inexpensive materials can be used on the downstream side from the mixing position P12. As a result, the manufacturing cost of the exhaust treatment device 3 can be reduced.

[0071] Preferably, the temperature of the exhaust gas flowing into the sulfur adsorption section 41 at the time of regeneration of the sulfur adsorption section 41 is 500°C or higher. Thus, the sulfur adsorption section 41 can be appropriately regenerated using high-temperature exhaust gas. In the flow path in which the high-temperature gas flows, expensive materials are required, but in the exhaust treatment device 3, the flow path for the high-temperature gas is limited to the section between the heater 51 and the mixing position P12, and inexpensive materials can be used in the other flow paths.

[0072] Preferably, the temperature of the exhaust gas after mixing at the mixing position P12 is 450°C or lower. In such an exhaust treatment device 3, more inexpensive materials can be used on the downstream side from the mixing position P12.

[0073] Preferably, the engine 10 uses a gas containing methane as fuel. The exhaust treatment device 3 is provided in the exhaust flow path 2 on the downstream side of the sulfur adsorption section 41, and has a methane oxidation catalyst 421 that oxidizes methane contained in the exhaust gas. Thus, methane slip can be reduced. In addition, the mixing position P12 is immediately after the methane oxidation catalyst 421, so the methane oxidation catalyst 421 can also be regenerated at the time of regeneration of the sulfur adsorption section 41. In addition, the length of the flow path for the high-temperature gas can be shortened, and the amount of use of expensive materials can be reduced.

[0074] Preferably, the exhaust treatment device 3 has a methane concentration measuring section 312 provided in the exhaust flow path 2 on the downstream side of the methane oxidation catalyst 421, which measures the methane concentration of the exhaust gas. The control section 30 determines the execution of the regeneration of the sulfur adsorption section 41 based on the measurement value of the methane concentration measuring section 312. Thus, the regeneration operation for regenerating the sulfur adsorption section 41 can be executed at an appropriate timing.

[0075] Preferably, the exhaust gas treatment device 3 includes a sulfur concentration measuring unit 313 disposed downstream of the sulfur adsorption unit 41 in the exhaust gas flow path 2 to measure the sulfur concentration of the exhaust gas. The control unit 30 determines the execution and termination of regeneration of the sulfur adsorption unit 41 based on the measurement value of the sulfur concentration measuring unit 313. Thus, regeneration operation can be performed and terminated at appropriate times. In the exhaust gas treatment device 3, either the execution or termination of regeneration of the sulfur adsorption unit 41 can be determined based on the measurement value of the sulfur concentration measuring unit 313.

[0076] Preferably, the exhaust gas treatment device 3 includes a temperature measuring unit 311 located downstream of the mixing position P12 to measure the temperature of the exhaust gas. Based on the measurement value from the temperature measuring unit 311, the control unit 30 adjusts the flow ratio of the portion of the exhaust gas passing through the sulfur adsorption unit 41 to the remaining portion of the exhaust gas passing through the heater bypass flow path 71. This allows for appropriate adjustment of the temperature of the mixed exhaust gas at the mixing position P12.

[0077] Another perspective Figure 1 The exhaust gas treatment device 3 includes: a sulfur adsorption section 41 disposed in the exhaust gas flow path 2 to adsorb sulfur-containing substances in the exhaust gas; a catalytic section 42 disposed downstream of the sulfur adsorption section 41 in the exhaust gas flow path 2 to oxidize or reduce specified substances in the exhaust gas; and a catalyst bypass flow path 76 disposed in the exhaust gas flow path 2 to bypass the target catalyst (in the catalytic section 42) included in the catalytic section 42. Figure 1 (The SCR catalyst 422 is shown in the image). The exhaust treatment device 3 also includes a gas temperature switching unit 5, a flow path switching unit 6, and a control unit 30. The gas temperature switching unit 5 can switch between a normal gas inflow state (exhaust gas at normal temperature flowing into the sulfur adsorption unit 41) and a high-temperature gas inflow state (exhaust gas at a higher temperature than normal flowing into the sulfur adsorption unit 41). The flow path switching unit 6 can switch between a bypass state (exhaust gas flowing in the catalyst bypass flow path 76) and a non-bypass state (exhaust gas flowing in the target catalyst). When the control unit 30 switches the gas temperature switching unit 5 from the normal gas inflow state to the high-temperature gas inflow state to perform the regeneration of the sulfur adsorption unit 41, it switches the flow path switching unit 6 from the non-bypass state to the bypass state. This suppresses sulfur poisoning of the target catalyst during the regeneration of the sulfur adsorption unit 41.

[0078] Preferably, the engine 10 uses a gas containing methane as fuel, and the catalytic converter 42 includes a methane oxidation catalyst 421 for oxidizing the methane contained in the exhaust gas. This reduces methane escape. In this case, the target catalyst of the catalytic converter 42 includes an SCR catalyst 422, thereby suppressing sulfur poisoning of the SCR catalyst 422 during the regeneration of the sulfur adsorption unit 41.

[0079] Preferably, the gas temperature switching section 5 heats a part of the exhaust gas using the heater 51 and causes it to flow into the sulfur adsorption section 41 in the high-temperature gas inflow state. The remaining part of the exhaust gas does not pass through the heater 51, and the part of the exhaust gas that has passed through the sulfur adsorption section 41 and the remaining part of the exhaust gas that has not passed through the heater 51 are mixed, and pass through the catalyst bypass flow path 76. Thereby, it is possible to lower the temperature of the gas flowing on the downstream side from the mixing position P12 at the time of the regeneration of the sulfur adsorption section 41, and it is possible to use inexpensive materials on the downstream side from the mixing position P12. As a result, it is possible to reduce the manufacturing cost of the exhaust treatment device 3.

[0080] (Second Embodiment)

[0081] Figure 4 is a view that shows the structure of the exhaust treatment device 3a of the second embodiment of the present application. In the exhaust treatment device 3a of Figure 4 , compared with the exhaust treatment device 3 of Figure 1 , the only difference is that only the heater 51 and the sulfur adsorption section 41 are housed in the reaction container 40, and the methane oxidation catalyst 421 is housed in a separate container. In addition, the auxiliary flow path 22, the valves 221, 222 are added. The other structures are the same as the exhaust treatment device 3 of Figure 1 , and the same reference numerals are attached to the same structures. In addition, the heater 51 and the sulfur adsorption section 41 can also be maintained in the order of Figure 4 and housed in a separate container.

[0082] One end of the auxiliary flow path 22 is connected to the connection position P21 between the sulfur adsorption section 41 and the methane oxidation catalyst 421 in the exhaust gas flow path 2 (refer to the thick solid line in Figure 4 ). The other end of the auxiliary flow path 22 is connected to the connection position P22 between the valve 211 and the connection position P12 in the heater bypass flow path 71. The valve 221 is provided to the auxiliary flow path 22. The valve 222 is provided to the exhaust gas flow path 2 between the connection position P21 and the methane oxidation catalyst 421. In the exhaust treatment device 3a, the other catalyst bypass flow path 76a that bypasses the methane oxidation catalyst 421 is constituted by the part of the auxiliary flow path 22 and the part between the connection position P22 and the connection position P12 of the heater bypass flow path 71. In addition, the other flow path switching section 6a is constituted by the valves 221, 222, 213. In the flow path switching section 6a, the valve 221 is opened and the valves 222, 213 are closed, whereby the exhaust gas that flows into the connection position P21 flows in the catalyst bypass flow path 76a without flowing in the methane oxidation catalyst 421, and the bypass state is established. In addition, the valve 221 is closed and the valves 222, 213 are opened, whereby the exhaust gas that flows into the connection position P21 flows in the methane oxidation catalyst 421 without flowing in the catalyst bypass flow path 76a, and the non-bypass state is established.

[0083] In the normal operation of the exhaust treatment device 3a, the valves 211, 221, 61 are closed and the other valves 212, 222, 213, 62, 63 are opened, whereby the exhaust gas flows along the exhaust flow path 2. At this time, the heater 51 is in an OFF state, and heating of the exhaust gas is not performed. That is, the gas temperature switching section 5 is in a normal gas inflow state in which the exhaust gas at the normal temperature flows toward the sulfur adsorption section 41. The sulfur-containing substance contained in the exhaust gas is adsorbed to the sulfur adsorption section 41. The flow path switching section 6a is in a non-bypass state in which the exhaust gas flows in the methane oxidation catalyst 421 and does not flow in the catalyst bypass flow path 76a. In the methane oxidation catalyst 421, the methane contained in the exhaust gas is oxidized. The flow path switching section 6 is in a non-bypass state in which the exhaust gas flows in the urea water supply section 429 and the SCR catalyst 422 and does not flow in the catalyst bypass flow path 76. In the SCR catalyst 422, the nitrogen oxide contained in the exhaust gas is reduced. In the control section 30, based on the measurement value of the sulfur concentration measurement section 313 or the measurement value of the methane concentration measurement section 312 of the measurement unit 31, or the like, it is determined to perform the regeneration of the sulfur adsorption section 41.

[0084] Figure 5 is a view for explaining the regeneration operation in the exhaust treatment device 3a. In the regeneration operation of the exhaust treatment device 3a, by the control of the control section 30, the flow path switching section 6a opens the valve 221 of the auxiliary flow path 22 and closes the valves 222, 213. Thereby, the bypass state in which the exhaust gas does not flow in the methane oxidation catalyst 421 and flows in the catalyst bypass flow path 76a is formed. In addition, the valve 211 of the heater bypass flow path 71 is gradually opened. In addition, the gas temperature switching section 5 switches the heater 51 to the ON state from the normal gas inflow state, whereby the high-temperature gas inflow state is switched.

[0085] In the connection position P11, a part of the exhaust gas flows toward the heater 51 (refer to the thick dashed line in Figure 5 ), and the remaining part of the exhaust gas flows into the heater bypass flow path 71 (refer to the thick single-dot chain line in Figure 5 ). The exhaust gas that has passed through the heater 51 flows into the sulfur adsorption section 41. Thereby, the sulfur-containing substance adsorbed to the sulfur adsorption section 41 is desorbed. The exhaust gas that has passed through the sulfur adsorption section 41 flows toward the connection position P22 via the connection position P21, and is mixed with the exhaust gas that has passed through the middle of the heater bypass flow path 71. In this way, the connection position P22 is a mixing position at which the high-temperature exhaust gas that has passed through the heater 51 and the exhaust gas that has not passed through the heater 51 are mixed. The temperature of the mixed exhaust gas at the mixing position P22 is below the limit temperature. The mixed exhaust gas passes through the portion of the heater bypass flow path 71 between the connection position P22 and the connection position P12.

[0086] As described above, in the exhaust treatment device 3a, the flow path switching section 6a is in the bypass state, and the exhaust gas of high temperature that has passed through the heater 51 does not flow in the methane oxidation catalyst 421. Thus, the sulfur poisoning of the methane oxidation catalyst 421 caused by the exhaust gas containing a high concentration of sulfur-containing substances is prevented. In addition, in the regeneration operation, the flow path switching section 6 opens the valve 61 and closes the valves 62, 63. Thus, the bypass state is formed in which the exhaust gas that has passed through the connection position P12 flows in the catalyst bypass flow path 76 without flowing in the urea water supply section 429 and the SCR catalyst 422. As a result, the sulfur poisoning of the SCR catalyst 422 caused by the exhaust gas containing a high concentration of sulfur-containing substances is prevented.

[0087] In the control section 30, when the end of the regeneration of the sulfur adsorption section 41 is determined on the basis of the measurement value of the sulfur concentration measurement section 313 or the execution time of the regeneration operation, and the like, the valve 222, 213 is opened and the valve 221 of the auxiliary flow path 22 is closed. Thus, the regeneration operation of regenerating the methane oxidation catalyst 421 is executed. In the following description, in order to distinguish from the regeneration operation of regenerating the sulfur adsorption section 41, the regeneration operation of regenerating the methane oxidation catalyst 421 is referred to as "additional regeneration operation".

[0088] Figure 6 is a view for explaining the additional regeneration operation in the exhaust treatment device 3a. In the additional regeneration operation, the exhaust gas of high temperature that has passed through the heater 51 and the sulfur adsorption section 41 passes through the methane oxidation catalyst 421 (refer to the thick dashed line in Figure 6 ), and the sulfur-containing substances adsorbed to the methane oxidation catalyst 421 are desorbed. In the additional regeneration operation, the heating temperature of the exhaust gas based on the heater 51 can also be different from the heating temperature at the time of the regeneration operation of regenerating the sulfur adsorption section 41, and in one example, the heating temperature of the exhaust gas at the time of the additional regeneration operation is lower than the heating temperature at the time of the regeneration operation. In the exhaust treatment device 3a, the regeneration of the sulfur adsorption section 41 and the regeneration of the methane oxidation catalyst 421 can be performed under respective appropriate individual temperature conditions. The exhaust gas that has passed through the methane oxidation catalyst 421 is mixed with the exhaust gas that has passed through the heater bypass flow path 71 (refer to the thick single-dot chain line in Figure 6 ). Thus, the connection position P12 is a mixing position at which the exhaust gas of high temperature that has passed through the heater 51 is mixed with the exhaust gas that has not passed through the heater 51. The temperature of the mixed exhaust gas at the mixing position P12 is below the limit temperature.

[0089] In addition, in the additional regeneration operation, the flow path switching portion 6 closes the valve 61 and opens the valve 62, the valve 63. Thereby, the non-bypass state in which the exhaust gas that has passed through the connection position P12 flows in the urea water supply portion 429 and the SCR catalyst 422 without flowing in the catalyst bypass flow path 76 is formed. In the methane oxidation catalyst 421, the adsorption amount of the sulfur-containing substance is small, and thus the concentration of the sulfur-containing substance contained in the exhaust gas is sufficiently low. Therefore, in the SCR catalyst 422, reduction in catalytic activity due to precipitation of ammonium bisulfate, ammonium sulfate does not occur, and nitrogen oxides are reduced. Further, depending on the adsorption amount of the sulfur-containing substance in the methane oxidation catalyst 421 and the like, the flow path switching portion 6 can also maintain the bypass state in the additional regeneration operation. Thereby, sulfur poisoning of the SCR catalyst 422 can be more reliably prevented.

[0090] In the control portion 30, at the end of the additional regeneration operation, the valve 211 of the heater bypass flow path 71 is gradually closed based on the measurement value of the sulfur concentration measurement portion 313 (for example, in a case where the measurement value becomes equal to or lower than a prescribed threshold value), or the execution time of the additional regeneration operation, and the like. In addition, the gas temperature switching portion 5 causes the heater 51 to become in the OFF state, and thereby switches from the high-temperature gas inflow state to the normal gas inflow state. Thereby, the additional regeneration operation in the exhaust treatment device 3a ends, and the normal operation is started again.

[0091] In a case where sulfur poisoning of the methane oxidation catalyst 421 is sufficiently suppressed by the sulfur adsorption portion 41, the additional regeneration operation can also be omitted. Depending on the temperature of the exhaust gas heated by the heater 51, sintering due to heat occurs in the methane oxidation catalyst 421, and the fine pores are clogged, and thus there is a possibility that performance reduction occurs, and thus in a case where the additional regeneration operation is omitted (that is, in a case where only the regeneration operation of regenerating the sulfur adsorption portion 41 is performed), deterioration due to sintering of the methane oxidation catalyst 421 is prevented.

[0092] As described above, in the exhaust treatment device 3a, at the time of regeneration of the sulfur adsorption portion 41, the exhaust gas that has passed through the sulfur adsorption portion 41 and the exhaust gas that has passed through the heater bypass flow path (a portion between the connection position P11 of the heater bypass flow path 71 and the mixing position P22 in Figure 5 the exhaust treatment device 3a) are mixed at the mixing position P22 on the downstream side of the sulfur adsorption portion 41. Thereby, in a case where regeneration of the methane oxidation catalyst 421 (the additional regeneration operation) is omitted, inexpensive materials can be used on the downstream side from the mixing position P22. In addition, the mixing position P22 is immediately after the sulfur adsorption portion 41, and thus the length of the flow path of the high-temperature gas flow can be shortened, and the amount of use of expensive materials can be reduced. In a case where the additional regeneration operation is performed, inexpensive materials can be used on the downstream side from the mixing position P12 at the time of regeneration of the methane oxidation catalyst 421.

[0093] Further, the control section 30 switches the flow path switching section 6 from the non-bypass state to the bypass state when the gas temperature switching section 5 is switched from the normal gas inflow state to the high-temperature gas inflow state to perform the regeneration of the sulfur adsorption section 41. Thereby, it is possible to suppress the sulfur poisoning of the target catalyst (the SCR catalyst 422 in this embodiment) at the time of the regeneration of the sulfur adsorption section 41. Figure 5

[0094] The exhaust treatment device 3a further has another catalyst bypass flow path 76a and another flow path switching section 6a. The catalyst bypass flow path 76a is provided to the exhaust flow path 2, bypassing the methane oxidation catalyst 421. The flow path switching section 6a is capable of switching between a bypass state in which the exhaust gas flows in the catalyst bypass flow path 76a, and a non-bypass state in which the exhaust gas flows in the methane oxidation catalyst 421. The control section 30 switches the flow path switching section 6a from the non-bypass state to the bypass state when performing the regeneration of the sulfur adsorption section 41. Thereby, it is possible to suppress the sulfur poisoning of the methane oxidation catalyst 421 at the time of the regeneration of the sulfur adsorption section 41.

[0095] In the exhaust treatment device 3a, the control section 30 maintains the gas temperature switching section 5 in the high-temperature gas inflow state and switches the flow path switching section 6a from the bypass state to the non-bypass state after the end of the regeneration of the sulfur adsorption section 41. Thereby, it is possible to continuously and efficiently regenerate the methane oxidation catalyst 421 from the start of the regeneration of the sulfur adsorption section 41.

[0096] (Third Embodiment)

[0097] Figure 7 is a diagram showing the structure of an exhaust treatment device 3b according to a third embodiment of the present application. In the exhaust treatment device 3b according to the third embodiment, Figure 7 compared with the exhaust treatment device 3 according to the first embodiment, the difference is that only the sulfur adsorption section 41 and the methane oxidation catalyst 421 are housed in the reaction container 40. Further, an auxiliary flow path 23 is added, in which a heater 51 and a valve 231 are provided. The other structures are the same as those of the exhaust treatment device 3 according to the first embodiment, and the same reference numerals are assigned to the same structures. Further, the sulfur adsorption section 41 and the methane oxidation catalyst 421 can also be maintained in the order of the first embodiment and housed in separate containers. Figure 1 Figure 1 Figure 7

[0098] One end of the auxiliary flow path 23 is connected to the exhaust flow path 2 (see Figure 7 ​​​​The other end of the auxiliary flow path 23 is connected to a connection position P32 between the valve 212 and the sulfur adsorption section 41 in the exhaust flow path 2. The valve 231 is provided in the auxiliary flow path 23 on the upstream side of the heater 51. In the exhaust treatment device 3b, the gas temperature switching section 5a is constituted by the valve 231 and the heater 51. As will be described later, the gas temperature switching section 5a closes the valve 231 and makes the heater 51 an OFF state, whereby the exhaust gas flows along the exhaust flow path 2, and a normal gas inflow state in which exhaust gas of a normal temperature flows to the sulfur adsorption section 41 is formed. By opening the valve 231 and making the heater 51 an ON state, whereby a part of the exhaust gas flows in the auxiliary flow path 23, and a high-temperature gas inflow state in which exhaust gas of a higher temperature than the normal temperature flows to the sulfur adsorption section 41 is formed.

[0099] In the normal operation of the exhaust treatment device 3b, the valves 231, 211, 61 are closed and the other valves 212, 213, 62, 63 are opened, whereby the exhaust gas flows along the exhaust flow path 2. At this time, the exhaust gas does not flow into the heater 51, and the heater 51 is in an OFF state. That is, the gas temperature switching section 5a is in a normal gas inflow state in which exhaust gas of a normal temperature flows to the sulfur adsorption section 41. The sulfur-containing substance contained in the exhaust gas is adsorbed to the sulfur adsorption section 41. In the methane oxidation catalyst 421, the methane contained in the exhaust gas is oxidized. In addition, the flow path switching section 6 is in a non-bypass state in which the exhaust gas flows in the urea water supply section 429 and the SCR catalyst 422 without flowing in the catalyst bypass flow path 76. In the SCR catalyst 422, the nitrogen oxide contained in the exhaust gas is reduced. In the control section 30, based on the measurement value of the sulfur concentration measurement section 313 or the measurement value of the methane concentration measurement section 312 of the measurement unit 31, or the like, the execution of the regeneration of the sulfur adsorption section 41 is determined.

[0100] Figure 8 is a view for explaining the regeneration operation in the exhaust treatment device 3b. In the regeneration operation of the exhaust treatment device 3b, the valve 211 of the heater bypass flow path 71 is gradually opened, and the valve 212 is closed. In addition, the gas temperature switching section 5a opens the valve 231 and makes the heater 51 an ON state, whereby the high-temperature gas inflow state is switched from the normal gas inflow state.

[0101] In the connection position P31, a part of the exhaust gas discharged from the engine 10 flows into the auxiliary flow path 23 and flows toward the heater 51 (refer to the thick broken line in Figure 8 In the heater 51, the exhaust gas is a gas (so-called bleed air) that has not passed through the turbine 161 and whose pressure and temperature have not decreased. In addition, the remaining part of the exhaust gas passes through the turbine 161 and the connection position P11 and flows into the heater bypass flow path 71 (refer to the thick broken line in Figure 8The exhaust gas that passed through the heater 51 is mixed at the mixing position P12 with the exhaust gas that passed through the heater bypass passage 71. Thus, the mixing position P12 is a mixing position at which the high-temperature exhaust gas that passed through the heater 51 is mixed with the exhaust gas that did not pass through the heater 51. The temperature of the mixed exhaust gas at the mixing position P12 is below the limit temperature.

[0102] In addition, in the regeneration operation, the passage switching section 6 opens the valve 61 and closes the valves 62 and 63. Thus, a bypass state in which the exhaust gas that passed through the mixing position P12 does not flow in the urea water supply section 429 and the SCR catalyst 422 but flows in the catalyst bypass passage 76 is formed. As a result, sulfur poisoning of the SCR catalyst 422 caused by the exhaust gas containing a high concentration of sulfur-containing substances is prevented.

[0103] In the control section 30, when the end of the regeneration operation is decided based on the measured value of the sulfur concentration measuring section 313 or the execution time of the regeneration operation, and the like, the valve 211 of the heater bypass passage 71 is gradually closed and the valve 212 is opened. In addition, the gas temperature switching section 5a closes the valve 231 and makes the heater 51 an OFF state, thereby switching from the high-temperature gas inflow state to the normal gas inflow state. In addition, the passage switching section 6 closes the valve 61 and opens the valves 62 and 63, thereby switching from the bypass state to the non-bypass state. Thus, the regeneration operation ends in the exhaust gas treatment device 3b, and the normal operation is started again.

[0104] As described above, in the exhaust gas treatment device 3b, at the time of regeneration of the sulfur adsorption section 41, the exhaust gas that passed through the sulfur adsorption section 41 and the exhaust gas that passed through the heater bypass passage (the portion of the exhaust gas passage 2 between the connection position P31 and the connection position P11, and the heater bypass passage 71) are mixed at the mixing position P12 on the downstream side of the sulfur adsorption section 41. Thus, it is possible to use inexpensive materials on the downstream side from the mixing position P12, and it is possible to reduce the manufacturing cost of the exhaust gas treatment device 3b. Figure 8

[0105] In addition, the control section 30 switches the passage switching section 6 from the non-bypass state to the bypass state when the gas temperature switching section 5a is switched from the normal gas inflow state to the high-temperature gas inflow state to perform the regeneration of the sulfur adsorption section 41. Thus, it is possible to suppress sulfur poisoning of the target catalyst (the SCR catalyst 422 in Figure 8

[0106] ​​In the exhaust treatment device 3b, a turbine 161 of a turbocharger 16 is provided in the exhaust flow path 2. When the gas temperature switching portion 5a is in the normal gas inflow state, the exhaust gas that has passed through the turbine 161 flows into the sulfur adsorption portion 41 and the catalytic portion 42. When the gas temperature switching portion 5a is in the high-temperature gas inflow state (i.e., at the time of regeneration of the sulfur adsorption portion 41), the exhaust gas taken out from between the engine 10 and the turbine 161 in the exhaust flow path 2 is heated by the heater 51 and flows into the sulfur adsorption portion 41. In this way, the high-temperature exhaust gas that is discharged from the engine 10 and does not pass through the turbine 161 is used for the regeneration of the sulfur adsorption portion 41, and thus it is possible to reduce the consumed energy in the heater 51.

[0107] Further, in the regeneration operation, in the case where the temperature of the exhaust gas (exhaust air) taken out from the auxiliary flow path 23 is sufficiently high, the heater 51 can be omitted. Thereby, it is possible to achieve a space-saving of the exhaust treatment device 3b and an efficient use of energy in the ship. In addition, the heating of the exhaust gas by the heater 51 can be performed only as assistance (as needed). In addition, in the case where the temperature of the exhaust gas taken out from the auxiliary flow path 23 is excessively high, the valve 212 is opened and the opening degree is adjusted, and thus it is also possible to mix the exhaust gas with the exhaust gas that has passed through the turbine 161, and to cause the exhaust gas whose temperature has been reduced to a certain degree to flow into the sulfur adsorption portion 41. The same applies to the exhaust treatment device 3c described later. Figure 8 Figure 9

[0108] (Fourth Embodiment)

[0109] Figure 9 is a view that shows the structure of the exhaust treatment device 3c of the fourth embodiment of the present application. In the exhaust treatment device 3c of Figure 4 , compared with the exhaust treatment device 3b of Figure 7 , the difference is that the sulfur adsorption portion 41 and the methane oxidation catalyst 421 are housed in separate containers. In addition, as with the exhaust treatment device 3a of Figure 4 , the auxiliary flow path 22, the valves 221, 222 are added. The other structures are the same as those of the exhaust treatment device 3b of Figure 7 , and the same reference numerals are attached to the same structures.

[0110] One end of the auxiliary flow path 22 is connected to the exhaust flow path 2 (refer to Figure 9 ​​The connection position P21 is connected to the connection position P12 between the valve 211 and the connection position P12 in the heater bypass flow path 71. The other end of the auxiliary flow path 22 is connected to the connection position P22 between the valve 211 and the connection position P12 in the heater bypass flow path 71. The valve 221 is provided to the auxiliary flow path 22. The valve 222 is provided to the exhaust gas flow path 2 between the connection position P21 and the methane oxidation catalyst 421. In the exhaust gas treatment device 3c, the other catalyst bypass flow path 76a that bypasses the methane oxidation catalyst 421 is constituted by the connection position P22 of the auxiliary flow path 22 and the portion between the connection position P12 and the connection position P12 of the heater bypass flow path 71. Further, the other flow path switching section 6a is constituted by the valves 221, 222, and 213. The flow path switching section 6a opens the valve 221 and closes the valves 222 and 213, thereby becoming a bypass state in which the exhaust gas flowing into the connection position P21 flows in the catalyst bypass flow path 76a without flowing in the methane oxidation catalyst 421. Further, the valve 221 is closed and the valves 222 and 213 are opened, thereby becoming a non-bypass state in which the exhaust gas flowing into the connection position P21 flows in the methane oxidation catalyst 421 without flowing in the catalyst bypass flow path 76a.

[0111] In the normal operation of the exhaust gas treatment device 3c, the valves 231, 211, 221, and 61 are closed and the other valves 212, 222, 213, 62, and 63 are opened, thereby the exhaust gas flows along the exhaust gas flow path 2. At this time, the exhaust gas does not flow into the heater 51, and the heater 51 is in an OFF state. That is, the gas temperature switching section 5a is in a normal gas inflow state in which the exhaust gas at a normal temperature flows into the sulfur adsorption section 41. Further, the flow path switching section 6a is in a non-bypass state in which the exhaust gas flows in the methane oxidation catalyst 421 without flowing in the catalyst bypass flow path 76a. The flow path switching section 6 is in a non-bypass state in which the exhaust gas flows in the urea water supply section 429 and the SCR catalyst 422 without flowing in the catalyst bypass flow path 76. In the control section 30, based on the measurement value of the sulfur concentration measurement section 313 or the measurement value of the methane concentration measurement section 312 of the measurement unit 31, or the like, the execution of the regeneration of the sulfur adsorption section 41 is determined.

[0112] Figure 10 is a view for explaining the regeneration operation in the exhaust gas treatment device 3c. In the regeneration operation of the exhaust gas treatment device 3c, the valve 211 of the heater bypass flow path 71 is gradually opened, and the valve 212 is closed. Further, the gas temperature switching section 5a opens the valve 231, and the heater 51 becomes in an ON state, thereby switching from the normal gas inflow state to the high-temperature gas inflow state. Moreover, the flow path switching section 6a opens the valve 221 of the auxiliary flow path 22 and closes the valves 222 and 213, thereby forming a bypass state in which the exhaust gas flows in the catalyst bypass flow path 76a without flowing in the methane oxidation catalyst 421.

[0113] At connection position P31, a portion of the exhaust gas discharged from engine 10 flows toward heater 51 (see reference). Figure 10 (Thick dashed line in the image). The remaining exhaust flows through turbine 161 and connection point P11 into heater bypass path 71 (see reference). Figure 10 (The bold dashed line in the image). The exhaust gas passing through heater 51 flows into sulfur adsorption section 41 via connection position P32. As a result, sulfur-containing substances adsorbed in sulfur adsorption section 41 are desorbed. The exhaust gas passing through sulfur adsorption section 41 mixes with the exhaust gas passing through heater bypass flow path 71 via connection position P21 towards connection position P22. Thus, connection position P22 is a mixing position where the high-temperature exhaust gas passing through heater 51 mixes with the exhaust gas not passing through heater 51. The temperature of the mixed exhaust gas at mixing position P22 is below a limiting temperature. The mixed exhaust gas passes through the portion of heater bypass flow path 71 between connection position P22 and connection position P12.

[0114] As described above, in the exhaust gas treatment device 3c, the flow path switching unit 6a is in a bypass state, and the high-temperature exhaust gas passing through the heater 51 does not flow in the methane oxidation catalyst 421. This prevents sulfur poisoning of the methane oxidation catalyst 421 caused by exhaust gas containing high concentrations of sulfur compounds. Furthermore, during regeneration operation, the flow path switching unit 6a opens valve 61 and closes valves 62 and 63. This creates a bypass state where the exhaust gas passing through connection position P12 does not flow in the urea water supply unit 429 and the SCR catalyst 422, but instead flows in the catalyst bypass flow path 76. As a result, sulfur poisoning of the SCR catalyst 422 caused by exhaust gas containing high concentrations of sulfur compounds is prevented.

[0115] In the control unit 30, when the regeneration of the sulfur adsorption unit 41 ends based on the measured value of the sulfur concentration measuring unit 313 or the execution time of the regeneration operation, valves 222 and 213 are opened and valve 221 of the auxiliary flow path 22 is closed. As a result, the additional regeneration operation of the regenerated methane oxidation catalyst 421 is performed.

[0116] Figure 11 This diagram illustrates the additional regeneration operation in the exhaust gas treatment unit 3c. During the additional regeneration operation, the high-temperature exhaust gas, having passed through heater 51 and sulfur adsorption section 41, passes through methane oxidation catalyst 421 (see reference). Figure 11 (Thick dashed line in the image), desorption of sulfur-containing compounds adsorbed on the methane oxidation catalyst 421. During additional regeneration operation, the heating temperature of the exhaust gas from heater 51 can differ from the heating temperature during the regeneration operation of the sulfur adsorption section 41. In the exhaust gas treatment device 3c, the regeneration of the sulfur adsorption section 41 and the regeneration of the methane oxidation catalyst 421 can be performed under their respective suitable individual temperature conditions. The exhaust gas passing through the methane oxidation catalyst 421 is directed towards the connection position P12, and the exhaust gas passing through the heater bypass flow path 71 (see reference...)Figure 11 The exhaust gas that has passed through the connection position P12 is mixed with the exhaust gas that has not passed through the heater 51. Thus, the connection position P12 is a mixing position where the exhaust gas that has passed through the heater 51 at a high temperature is mixed with the exhaust gas that has not passed through the heater 51. The temperature of the mixed exhaust gas at the mixing position P12 is below the limit temperature.

[0117] In addition, in the additional regeneration operation, the flow path switching section 6 closes the valve 61 and opens the valve 62 and the valve 63. Thus, the non-bypass state in which the exhaust gas that has passed through the connection position P12 does not flow in the catalyst bypass flow path 76 but flows in the urea water supply section 429 and the SCR catalyst 422 is formed. In the methane oxidation catalyst 421, the adsorption amount of the sulfur-containing substance is small, and thus the concentration of the sulfur-containing substance contained in the exhaust gas is sufficiently low. Therefore, in the SCR catalyst 422, the reduction in catalytic activity caused by the precipitation of ammonium bisulfate and ammonium sulfate does not occur, and the nitrogen oxide is reduced. In addition, depending on the adsorption amount of the sulfur-containing substance in the methane oxidation catalyst 421 and the like, the flow path switching section 6 can maintain the bypass state in the additional regeneration operation. Thus, the sulfur poisoning of the SCR catalyst 422 can be more reliably prevented.

[0118] In the control section 30, when the end of the additional regeneration operation is decided on the basis of the measurement value of the sulfur concentration measurement section 313 or the execution time of the additional regeneration operation and the like, the valve 211 of the heater bypass flow path 71 is gradually closed, and the valve 212 is opened. In addition, the gas temperature switching section 5a closes the valve 231, and the heater 51 is switched from the high-temperature gas inflow state to the normal gas inflow state. Thus, the regeneration operation ends in the exhaust treatment device 3c, and the normal operation is started again.

[0119] As with the exhaust treatment device 3a of Figure 4 In the case where the sulfur poisoning of the methane oxidation catalyst 421 is sufficiently suppressed by the sulfur adsorption section 41, the additional regeneration operation can also be omitted. Depending on the temperature of the exhaust gas in the high-temperature gas inflow state, it is possible that the deterioration caused by the sintering due to heat is caused in the methane oxidation catalyst 421, and thus in the case where the additional regeneration operation is omitted (i.e., in the case where only the regeneration operation of the sulfur adsorption section 41 is performed), the deterioration caused by the sintering of the methane oxidation catalyst 421 is prevented.

[0120] As described above, in the exhaust treatment device 3c, when the sulfur adsorption section 41 is regenerated, the exhaust gas that has passed through the sulfur adsorption section 41 and the exhaust gas that has not passed through the heater bypass flow path (in the exhaust treatment device 3a, the exhaust gas that has passed through the heater bypass flow path 71 and the exhaust gas that has not passed through the heater bypass flow path 71) are mixed. Figure 10In the process, the exhaust gas from the portion between the connection position P31 and the connection position P11 of the exhaust flow path 2, and the portion between the connection position P11 and the mixing position P22 of the heater bypass flow path 71, is mixed at the mixing position P22 downstream of the sulfur adsorption section 41. Therefore, without requiring additional regeneration operation, inexpensive materials can be used downstream from the mixing position P22. In the case of additional regeneration operation, inexpensive materials can be used downstream from the mixing position P12 during the regeneration of the methane oxidation catalyst 421.

[0121] Furthermore, when the control unit 30 switches the gas temperature switching unit 5a from a normal gas inflow state to a high-temperature gas inflow state to perform the regeneration of the sulfur adsorption unit 41, it switches the flow path switching unit 6 from a non-bypass state to a bypass state. This allows for the suppression of the target catalyst (in the sulfur adsorption unit 41) during regeneration. Figure 10 The sulfur poisoning of SCR catalyst 422.

[0122] In the exhaust treatment device 3c, during the regeneration of the sulfur adsorption section 41, the exhaust gas taken from between the engine 10 and the turbine 161 in the exhaust flow path 2 is heated by the heater 51 and flows into the sulfur adsorption section 41. In this way, the high-temperature exhaust gas discharged from the engine 10 that has not passed through the turbine 161 is used for the regeneration of the sulfur adsorption section 41, thereby reducing the energy consumption in the heater 51.

[0123] The exhaust treatment device 3c also includes other catalyst bypass flow paths 76a and other flow path switching units 6a. The catalyst bypass flow path 76a is provided in the exhaust flow path 2, bypassing the methane oxidation catalyst 421. The flow path switching unit 6a can switch between a bypass state where exhaust flows in the catalyst bypass flow path 76a and a non-bypass state where exhaust flows in the methane oxidation catalyst 421. When the control unit 30 performs regeneration of the sulfur adsorption unit 41, it switches the flow path switching unit 6a from the non-bypass state to the bypass state. This suppresses sulfur poisoning of the methane oxidation catalyst 421 during the regeneration of the sulfur adsorption unit 41.

[0124] (Fifth Implementation)

[0125] Figure 12 This is a diagram showing the structure of the exhaust treatment apparatus 3d according to the fifth embodiment of the present invention. Figure 12 In the exhaust treatment device 3d, with Figure 1 Compared to the exhaust treatment device 3, the difference is that the heater 51, sulfur adsorption section 41, methane oxidation catalyst 421, and heater bypass flow path 71a are arranged in the exhaust flow path 2 (see reference). Figure 12 The engine 10 and turbine 161 are shown in the thick solid line (in the image). Other structures are... Figure 1 The exhaust treatment device 3 is the same, and the same reference numerals are used to label the same structures. Additionally, in Figure 12In the exhaust treatment device 3d, the heater 51, the sulfur adsorption section 41, and the methane oxidation catalyst 421 are housed in one reaction container 40, but the heater 51, the sulfur adsorption section 41, and the methane oxidation catalyst 421 can also be housed in separate containers in this order. Figure 12

[0126] In the exhaust treatment device 3d, the heater 51, the sulfur adsorption section 41, and the methane oxidation catalyst 421 are arranged in this order in the exhaust flow path 2 from the exhaust manifold 12 toward the turbine 161. One end of the heater bypass flow path 71a is connected to the connection position P51 between the exhaust manifold 12 and the heater 51 in the exhaust flow path 2. The other end of the heater bypass flow path 71a is connected to the connection position P52 between the methane oxidation catalyst 421 and the turbine 161 in the exhaust flow path 2. A valve 214 is provided in the heater bypass flow path 71a. The valve 214 is, for example, a flow rate adjustment valve, and the opening degree of the valve 214 is adjusted by the control section 30, whereby the flow rate of the exhaust gas flowing in the heater bypass flow path 71a can be adjusted. In the exhaust flow path 2, a valve 215 is provided between the connection position P51 and the heater 51, and a valve 216 is provided between the methane oxidation catalyst 421 and the connection position P52. The opening and closing of the valves 215 and 216 are controlled by the control section 30.

[0127] In the normal operation of the exhaust treatment device 3d, the valves 214 and 61 are closed and the other valves 215, 216, 62, and 63 are opened, whereby the exhaust gas flows along the exhaust flow path 2. At this time, the heater 51 is in the OFF state. That is, the gas temperature switching section 5 is in the normal gas inflow state in which the exhaust gas at the normal temperature flows toward the sulfur adsorption section 41. The sulfur-containing substance included in the exhaust gas is adsorbed to the sulfur adsorption section 41. The methane included in the exhaust gas is oxidized in the methane oxidation catalyst 421. The exhaust gas that has passed through the methane oxidation catalyst 421 flows toward the connection position P13 via the connection position P52 and the turbine 161. The flow path switching section 6 is in the non-bypass state, and the exhaust gas flows in the urea water supply section 429 and the SCR catalyst 422. The nitrogen oxide included in the exhaust gas is reduced in the SCR catalyst 422. In the control section 30, based on the measurement value of the sulfur concentration measurement section 313 or the measurement value of the methane concentration measurement section 312 of the measurement unit 31, or the like, it is determined whether to execute the regeneration of the sulfur adsorption section 41.

[0128] Figure 13 is a view for explaining the regeneration operation in the exhaust treatment device 3d. In the regeneration operation of the exhaust treatment device 3d, the valve 214 of the heater bypass flow path 71a is gradually opened. In addition, the gas temperature switching section 5 switches the heater 51 to the ON state, whereby the normal gas inflow state is switched to the high-temperature gas inflow state.

[0129] At the connection position P51, a part of the exhaust gas flows toward the heater 51 (refer to Figure 13 ​the remaining portion of the exhaust gas flows into the heater bypass flow path 71a (refer to Figure 13 The exhaust gas that passed through the heater 51 flows into the sulfur adsorption section 41 and the methane oxidation catalyst 421. Thereby, the sulfur-containing substance adsorbed to the sulfur adsorption section 41 and the methane oxidation catalyst 421 is desorbed. The exhaust gas that passed through the methane oxidation catalyst 421 is mixed with the exhaust gas that passed through the heater bypass flow path 71a toward the connection position P52. In this way, the connection position P52 is a mixing position at which the high-temperature exhaust gas that passed through the heater 51 is mixed with the exhaust gas that did not pass through the heater 51. The temperature of the mixed exhaust gas at the mixing position P52 is below the limit temperature. The mixed exhaust gas passes through the turbine 161 toward the connection position P13.

[0130] In the regeneration operation, the flow path switching section 6 opens the valve 61 and closes the valves 62 and 63. Thereby, a bypass state in which the exhaust gas that reaches the connection position P13 does not flow in the urea water supply section 429 and the SCR catalyst 422 but flows in the catalyst bypass flow path 76 is formed. As a result, the sulfur poisoning of the SCR catalyst 422 by the exhaust gas containing a high concentration of the sulfur-containing substance is prevented.

[0131] In the control section 30, when the end of the regeneration operation is determined on the basis of the measurement value of the sulfur concentration measurement section 313 or the execution time of the regeneration operation, and the like, the valve 214 of the heater bypass flow path 71a is gradually closed. In addition, the gas temperature switching section 5 makes the heater 51 into an OFF state, thereby switching from the high-temperature gas inflow state to the normal gas inflow state. In addition, the flow path switching section 6 closes the valve 61 and opens the valves 62 and 63, thereby switching from the bypass state to the non-bypass state. In this way, the regeneration operation ends in the exhaust gas treatment device 3d, and the normal operation is started again.

[0132] As described above, in the exhaust gas treatment device 3d, at the time of the regeneration of the sulfur adsorption section 41, the exhaust gas that passed through the sulfur adsorption section 41 and the exhaust gas that passed through the heater bypass flow path 71a are mixed at the mixing position P52 on the downstream side of the sulfur adsorption section 41. Thereby, it is possible to use inexpensive materials on the downstream side from the mixing position P52, and it is possible to reduce the manufacturing cost of the exhaust gas treatment device 3d.

[0133] In addition, the control section 30 switches the flow path switching section 6 from the non-bypass state to the bypass state at the time of the regeneration of the sulfur adsorption section 41 in which the gas temperature switching section 5 is switched from the normal gas inflow state to the high-temperature gas inflow state. Thereby, it is possible to suppress the sulfur poisoning of the target catalyst (the SCR catalyst 422 in Figure 13 ) at the time of the regeneration of the sulfur adsorption section 41.

[0134] In the exhaust treatment device 3d, the turbine 161 of the turbocharger 16 is provided in the exhaust flow path 2, and the methane oxidation catalyst 421 is provided between the engine 10 and the turbine 161. In this way, the methane oxidation catalyst 421 is arranged in high-pressure exhaust gas, and thus the activity of the methane oxidation catalyst 421 can be increased to oxidize methane in the exhaust gas efficiently. In addition, the sulfur adsorption section 41 is provided in the exhaust flow path 2 between the engine 10 and the turbine 161, and thus the activity reduction of the methane oxidation catalyst 421 and the SCR catalyst 422 can be suppressed, and the sulfuric acid corrosion of the blades and the deposition of the deposits from sulfur in the blades and the housing in the turbine 161 can be suppressed.

[0135] (Sixth Embodiment)

[0136] Figure 14 is a view that shows the structure of the exhaust treatment device 3e of the sixth embodiment of the present application. In Figure 14 the exhaust treatment device 3e, compared with Figure 12 the exhaust treatment device 3d, the only difference is that the heater 51 and the sulfur adsorption section 41 are housed in the reaction container 40, and the methane oxidation catalyst 421 is housed in a separate container. In addition, the auxiliary flow path 22a and the valves 223, 224 are added. The other structures are the same as those of Figure 12 the exhaust treatment device 3d, and the same reference numerals are attached to the same structures. In addition, the heater 51 and the sulfur adsorption section 41 can also be housed in a separate container in the order of Figure 14 .

[0137] One end of the auxiliary flow path 22a is connected to the connection position P61 between the sulfur adsorption section 41 and the methane oxidation catalyst 421 in the exhaust flow path 2 (refer to the bold line in Figure 14 ). The other end of the auxiliary flow path 22a is connected to the connection position P62 between the valve 214 and the connection position P52 in the heater bypass flow path 71a. The valve 223 is provided in the auxiliary flow path 22a. The valve 224 is provided in the exhaust flow path 2 between the connection position P61 and the methane oxidation catalyst 421. In the exhaust treatment device 3e, the other catalyst bypass flow path 76b that bypasses the methane oxidation catalyst 421 is constituted by the connection position P62 and the connection position P52 between the auxiliary flow path 22a and the heater bypass flow path 71a. In addition, the other flow path switching section 6b is constituted by the valves 223, 224, 216. The flow path switching section 6b opens the valve 223 and closes the valves 224, 216, and thus becomes a bypass state in which the exhaust gas that flows into the connection position P61 flows in the catalyst bypass flow path 76b without flowing in the methane oxidation catalyst 421. In addition, the valve 223 is closed and the valves 224, 216 are opened, and thus becomes a non-bypass state in which the exhaust gas that flows into the connection position P61 flows in the methane oxidation catalyst 421 without flowing in the catalyst bypass flow path 76b.

[0138] In the normal operation of the exhaust treatment device 3e, the valves 214, 223, 61 are closed and the other valves 215, 224, 216, 62, 63 are opened, whereby the exhaust gas flows along the exhaust flow path 2. At this time, the heater 51 is in the OFF state, and heating of the exhaust gas is not performed. That is, the gas temperature switching portion 5 is in the normal gas inflow state in which the exhaust gas at the normal temperature flows toward the sulfur adsorption portion 41. The sulfur-containing substance contained in the exhaust gas is adsorbed to the sulfur adsorption portion 41. The flow path switching portion 6b is in the non-bypass state in which the exhaust gas flows in the methane oxidation catalyst 421 and does not flow in the catalyst bypass flow path 76b. In the methane oxidation catalyst 421, the methane contained in the exhaust gas is oxidized. The exhaust gas that has passed through the methane oxidation catalyst 421 passes through the connection position P52 and the turbine 161 toward the connection position P13. The flow path switching portion 6 is in the non-bypass state in which the exhaust gas flows in the urea water supply portion 429 and the SCR catalyst 422 and does not flow in the catalyst bypass flow path 76. In the SCR catalyst 422, the nitrogen oxide contained in the exhaust gas is reduced. In the control portion 30, based on the measurement value of the sulfur concentration measurement portion 313 or the measurement value of the methane concentration measurement portion 312 of the measurement unit 31, or the like, it is determined to perform the regeneration of the sulfur adsorption portion 41.

[0139] Figure 15 is a view for explaining the regeneration operation in the exhaust treatment device 3e. In the regeneration operation of the exhaust treatment device 3e, the flow path switching portion 6b opens the valve 223 of the auxiliary flow path 22a and closes the valves 224, 216. Thereby, the bypass state in which the exhaust gas does not flow in the methane oxidation catalyst 421 and flows in the catalyst bypass flow path 76b is formed. In addition, the valve 214 of the heater bypass flow path 71a is gradually opened. In addition, the gas temperature switching portion 5 switches the heater 51 to the ON state from the normal gas inflow state, whereby the high-temperature gas inflow state is switched.

[0140] At the connection position P51, a part of the exhaust gas flows toward the heater 51 (refer to the thick broken line in Figure 15 At the connection position P51, a part of the exhaust gas flows toward the heater 51 (refer to the thick broken line in Figure 15 At the connection position P51, a part of the exhaust gas flows toward the heater 51 (refer to the thick broken line in

[0141] As described above, in the exhaust treatment device 3e, the flow path switching section 6b is in the bypass state, and the exhaust gas of high temperature that has passed through the heater 51 does not flow in the methane oxidation catalyst 421. Thus, the sulfur poisoning of the methane oxidation catalyst 421 caused by the exhaust gas containing high concentration of sulfur-containing substances is prevented. The exhaust gas that has passed through the connection position P52 is directed toward the connection position P13 via the turbine 161. In the regeneration operation, the flow path switching section 6 opens the valve 61 and closes the valves 62, 63. Thus, the bypass state is formed in which the exhaust gas that has passed through the connection position P52 does not flow in the urea water supply section 429 and the SCR catalyst 422 but flows in the catalyst bypass flow path 76. As a result, the sulfur poisoning of the SCR catalyst 422 caused by the exhaust gas containing high concentration of sulfur-containing substances is prevented.

[0142] In the control section 30, when the end of the regeneration of the sulfur adsorption section 41 is determined on the basis of the measured value of the sulfur concentration measuring section 313 or the execution time of the regeneration operation, etc., the valve 224, 216 is opened and the valve 223 of the auxiliary flow path 22a is closed. Thus, the additional regeneration operation for regenerating the methane oxidation catalyst 421 is executed.

[0143] Figure 16 is a view for explaining the additional regeneration operation in the exhaust treatment device 3e. In the additional regeneration operation, the exhaust gas of high temperature that has passed through the heater 51 and the sulfur adsorption section 41 passes through the methane oxidation catalyst 421 (refer to the thick dashed line in Figure 16 ), and the sulfur-containing substances adsorbed to the methane oxidation catalyst 421 are desorbed. In the additional regeneration operation, the heating temperature of the exhaust gas based on the heater 51 can also be different from the heating temperature at the time of the regeneration operation for regenerating the sulfur adsorption section 41. In the exhaust treatment device 3e, the regeneration of the sulfur adsorption section 41 and the regeneration of the methane oxidation catalyst 421 can be performed under respective appropriate individual temperature conditions. The exhaust gas that has passed through the methane oxidation catalyst 421 is directed toward the connection position P52, and is mixed with the exhaust gas that has passed through the heater bypass flow path 71a (refer to the thick single-dot chain line in Figure 16 ). In this way, the connection position P52 is a mixing position at which the exhaust gas of high temperature that has passed through the heater 51 is mixed with the exhaust gas that has not passed through the heater 51. The temperature of the mixed exhaust gas at the mixing position P52 is below the limit temperature.

[0144] In addition, in the additional regeneration operation, the flow path switching portion 6 closes the valve 61 and opens the valve 62, the valve 63. Thereby, the non-bypass state in which the exhaust gas that has passed through the connection position P52 and the turbine 161 does not flow in the catalyst bypass flow path 76 but flows in the urea water supply portion 429 and the SCR catalyst 422 is formed. In the methane oxidation catalyst 421, the adsorption amount of the sulfur-containing substance is small, and the concentration of the sulfur-containing substance contained in the exhaust gas is sufficiently low, and thus the reduction in catalytic activity due to the precipitation of ammonium bisulfate, ammonium sulfate does not occur in the SCR catalyst 422. Further, depending on the adsorption amount of the sulfur-containing substance in the methane oxidation catalyst 421 and the like, in the additional regeneration operation, the flow path switching portion 6 can also maintain the bypass state. Thereby, the sulfur poisoning of the SCR catalyst 422 can be more reliably prevented.

[0145] In the control portion 30, when the end of the additional regeneration operation is decided based on the measurement value of the sulfur concentration measurement portion 313 or the execution time of the additional regeneration operation and the like, the valve 214 of the heater bypass flow path 71a is gradually closed. In addition, the gas temperature switching portion 5 makes the heater 51 into the OFF (off) state, and thereby switches from the high-temperature gas inflow state to the normal gas inflow state. Thereby, the additional regeneration operation in the exhaust treatment device 3e ends, and the normal operation is started again.

[0146] As with the exhaust treatment device 3a of Figure 4 , in a case where the sulfur poisoning of the methane oxidation catalyst 421 is sufficiently suppressed by the sulfur adsorption portion 41, the additional regeneration operation can also be omitted. Depending on the temperature of the exhaust gas heated by the heater 51, it is possible that the deterioration due to the sintering caused by heat occurs in the methane oxidation catalyst 421, and thus in a case where the additional regeneration operation is omitted (that is, in a case where only the regeneration operation of regenerating the sulfur adsorption portion 41 is performed), the deterioration due to the sintering of the methane oxidation catalyst 421 is prevented.

[0147] As described above, in the exhaust treatment device 3e, at the time of the regeneration of the sulfur adsorption portion 41, the exhaust gas that has passed through the sulfur adsorption portion 41 and the exhaust gas that has passed through the portion of the heater bypass flow path (the portion between the connection position P51 and the mixing position P62 in the Figure 15 ) mixes at the mixing position P62 on the downstream side of the sulfur adsorption portion 41. Thereby, in a case where the additional regeneration operation is omitted, inexpensive materials can be used on the downstream side from the mixing position P62. In a case where the additional regeneration operation is performed, inexpensive materials can be used on the downstream side from the mixing position P52 at the time of the regeneration of the methane oxidation catalyst 421.

[0148] Further, the control section 30 switches the flow path switching section 6 from the non-bypass state to the bypass state when the gas temperature switching section 5 is switched from the normal gas inflow state to the high-temperature gas inflow state to perform the regeneration of the sulfur adsorption section 41. Thus, the sulfur poisoning of the target catalyst (the SCR catalyst 422 in the present embodiment) at the time of the regeneration of the sulfur adsorption section 41 can be suppressed. Figure 15

[0149] In the exhaust treatment device 3e, the methane oxidation catalyst 421 is provided in the exhaust flow path 2 between the engine 10 and the turbine 161, whereby the activity of the methane oxidation catalyst 421 can be raised to oxidize the methane in the exhaust gas efficiently. Further, the sulfur adsorption section 41 is provided between the engine 10 and the turbine 161, whereby the sulfuric acid corrosion of the blades in the turbine 161 and the deposition of the deposits from sulfur in the blades and the housing can be suppressed.

[0150] The exhaust treatment device 3e is provided with the other catalyst bypass flow path 76b and the other flow path switching section 6b. The catalyst bypass flow path 76b is provided in the exhaust flow path 2 to bypass the methane oxidation catalyst 421. The flow path switching section 6b can switch between the bypass state in which the exhaust gas flows in the catalyst bypass flow path 76b and the non-bypass state in which the exhaust gas flows in the methane oxidation catalyst 421. The control section 30 switches the flow path switching section 6b from the non-bypass state to the bypass state when the regeneration of the sulfur adsorption section 41 is performed. Thus, the sulfur poisoning of the methane oxidation catalyst 421 at the time of the regeneration of the sulfur adsorption section 41 can be suppressed.

[0151] Various modifications can be made in the above-described exhaust treatment devices 3, 3a to 3e.

[0152] In the exhaust treatment devices 3, 3a to 3e, for example, the sulfur adsorption section 41 and the SCR catalyst 422 can be omitted. Figure 17 In the exhaust treatment device 3 of the above-described embodiment, the heater 51, the methane oxidation catalyst 421, and the heater bypass flow path 71 are provided in the exhaust flow path 2. The heater bypass flow path 71 bypasses the heater 51 and the methane oxidation catalyst 421. Figure 17 ​In the example, during normal operation, sulfur-containing substances are adsorbed onto the methane oxidation catalyst 421. That is, the methane oxidation catalyst 421 oxidizes the methane contained in the exhaust gas and adsorbs sulfur-containing substances in the exhaust gas, thus also functioning as a sulfur adsorption section. During the regeneration of the methane oxidation catalyst 421, a portion of the exhaust gas is heated by the heater 51 and flows into the methane oxidation catalyst 421, while the remaining portion of the exhaust gas flows into the bypass flow path 71. Moreover, in the flow path through which this portion of the exhaust gas flows, at the mixing position P12 immediately following the methane oxidation catalyst 421, this portion of the exhaust gas passing through the methane oxidation catalyst 421 and the remaining portion of the exhaust gas passing through the heater bypass flow path 71 are mixed. As a result, the temperature of the gas flowing downstream from the mixing position P12 during the regeneration of the methane oxidation catalyst 421 can be reduced, and inexpensive materials can be used downstream from the mixing position P12.

[0153] In the exhaust treatment device 3, which omits the sulfur adsorption section 41 and the SCR catalyst 422, such as Figure 18 As shown, it can also be compared with Figure 7 The auxiliary flow path 23a of the exhaust treatment device 3b is the same as that of the exhaust flow path 2, and the heater 51 is installed in the auxiliary flow path 23a. Figure 18 In the exhaust treatment device 3, during normal operation, the exhaust gas does not flow in the auxiliary flow path 23a; during regeneration operation, the exhaust gas flows in the auxiliary flow path 23a. Alternatively, the position of the turbine 161 of the turbocharger 16 can be changed to... Figure 18 At the location indicated by the double-dotted line, exhaust gas (extraction gas) flowing between engine 10 and turbine 161 during regeneration operation flows into auxiliary flow path 23a.

[0154] If pressure loss is not a problem, the heater 51 may not be installed inside the container, but rather inside the exhaust flow path 2. As long as the exhaust gas flowing into the sulfur adsorption section 41 can be heated by the heater 51, the heater 51 can be placed at any position between the engine 10 and the sulfur adsorption section 41 in the exhaust flow path.

[0155] According to the design of engine system 1, the temperature of the exhaust gas flowing into sulfur adsorption section 41 during regeneration can be less than 500°C. Furthermore, the temperature of the mixed exhaust gas at the mixing position can be higher than 450°C. Moreover, the catalyst bypass path 76 can be omitted.

[0156] The temperature measuring section 311 can be disposed at any position as long as it can measure the temperature of the exhaust gas after mixing of the exhaust gas that has passed through the sulfur adsorption section 41 and the exhaust gas that has passed through the heater bypass flow path. The methane concentration measuring section 312 can be disposed at any position as long as it can measure the methane concentration of the exhaust gas that has passed through the methane oxidation catalyst 421 in normal operation. The sulfur concentration measuring section 313 can be disposed at any position as long as it can measure the sulfur concentration of the exhaust gas that has passed through the sulfur adsorption section 41 in normal operation and / or in regeneration operation.

[0157] In the above-described embodiments, the exhaust treatment device 3, 3a to 3e is described as being provided in a ship, but the exhaust treatment device 3, 3a to 3e can be provided in a power plant or the like, or various devices that use an engine. In addition, a fuel that does not contain methane can be used in the engine, and the exhaust treatment device 3, 3a to 3e can not contain the methane oxidation catalyst 421.

[0158] The structures of the above-described embodiments and the variations can be appropriately combined as long as they do not contradict each other.

[0159] Although the application has been described and illustrated in detail, it is not intended that the application is restricted to the above-described embodiments, and the above-described description is illustrative and not restrictive. Therefore, various modifications, modes, and the like can be made as long as they do not depart from the scope of the application.

[0160] Explanation of Reference Signs

[0161] 2 Exhaust flow path

[0162] 3, 3a to 3e Exhaust treatment device

[0163] 10 Engine

[0164] 16 Turbocharger

[0165] 30 Control section

[0166] 41 Sulfur adsorption section

[0167] 51 Heater

[0168] 71, 71a Heater bypass flow path

[0169] 161 Turbine

[0170] 311 Temperature measuring section

[0171] 312 Methane concentration measuring section

[0172] 313 Sulfur concentration measuring section

[0173] 421 Methane oxidation catalyst

[0174] P12, P22, P52, P62 Mixing position

Claims

1. An exhaust gas treatment device, characterized in that, have: A sulfur adsorption section is provided in the exhaust flow path for the exhaust gas discharged from the engine, and adsorbs sulfur-containing substances in the exhaust gas. A heater capable of heating the exhaust gas flowing into the sulfur adsorption section; A heater bypass flow path is provided in the exhaust flow path, bypassing the heater and the sulfur adsorption section; and The control unit, during the regeneration of the sulfur adsorption unit, heats a portion of the exhaust gas using the heater and directs it into the sulfur adsorption unit, while the remaining portion of the exhaust gas flows into the heater bypass path. During the regeneration of the sulfur adsorption section, in the flow path that supplies the portion of the exhaust gas, at the mixing position downstream of the sulfur adsorption section, the portion of the exhaust gas that has passed through the sulfur adsorption section mixes with the remaining portion of the exhaust gas that has passed through the heater bypass flow path.

2. The exhaust gas treatment device according to claim 1, characterized in that, During the regeneration of the sulfur adsorption section, the temperature of the exhaust gas flowing into the sulfur adsorption section is above 500°C.

3. The exhaust gas treatment device according to claim 1, characterized in that, The temperature of the mixed exhaust gas at the mixing location is below 450°C.

4. The exhaust gas treatment device according to claim 1, characterized in that, The engine uses gas containing methane as fuel. The exhaust treatment device also includes: A methane oxidation catalyst, disposed downstream of the sulfur adsorption section in the exhaust gas flow path, oxidizes the methane contained in the exhaust gas. The mixing position is immediately following the sulfur adsorption section or immediately following the methane oxidation catalyst.

5. The exhaust gas treatment device according to claim 1, characterized in that, The engine uses gas containing methane as fuel. A methane oxidation catalyst is provided in the exhaust flow path. The methane oxidation catalyst oxidizes the methane contained in the exhaust gas and adsorbs sulfur-containing substances in the exhaust gas, thereby also functioning as the sulfur adsorption unit. The mixing location is immediately following the methane oxidation catalyst.

6. The exhaust gas treatment device according to claim 4 or 5, characterized in that, It also includes a methane concentration measuring unit, which is disposed downstream of the methane oxidation catalyst in the exhaust flow path to measure the methane concentration in the exhaust gas. The control unit determines the regeneration of the sulfur adsorption unit based on the measurement value of the methane concentration measuring unit.

7. The exhaust gas treatment apparatus according to any one of claims 1-5, characterized in that, It also includes a temperature measuring unit, which is located downstream of the mixing position, to measure the temperature of the exhaust gas. The control unit adjusts the flow ratio of the portion of the exhaust gas to the remaining portion of the exhaust gas based on the measurement value of the temperature measuring unit.

8. The exhaust gas treatment apparatus according to any one of claims 1-5, characterized in that, It also includes a sulfur concentration measuring unit, which is disposed downstream of the sulfur adsorption unit in the exhaust flow path to measure the sulfur concentration of the exhaust gas. The control unit determines the execution of regeneration of the sulfur adsorption unit and / or the termination of regeneration of the sulfur adsorption unit based on the measurement value of the sulfur concentration measuring unit.

9. The exhaust gas treatment apparatus according to any one of claims 1-5, characterized in that, The exhaust path is equipped with a turbocharger turbine. During the regeneration of the sulfur adsorption section, the exhaust gas taken from between the engine and the turbine in the exhaust flow path is heated by the heater.

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