A flat plate denitration catalyst activity detection system and method

Abstract

The present invention provides a system and method for detecting the activity of a flat-plate denitration catalyst. The detection system includes: an air supply unit, including two or more air storage devices; an air distribution unit, including a control valve arranged at the outlet end of each air storage device; a reaction unit, including a reaction device and a heating device, the reaction device is connected to the air distribution unit and has a reaction chamber for accommodating a flat-plate denitration catalyst; an analysis unit, including a sampling device and a detection device, the sampling device has a first sampling port and a second sampling port respectively connected to the front end and the rear end of the flat-plate denitration catalyst, and the detection device is connected to the outlet end of the sampling device; a control unit, which can control the air distribution unit according to the information fed back by the analysis unit. The detection system of the present invention has a simple structure, low cost, good repeatability, and strong applicability, and can ensure the accuracy and comparability of the detection results when detecting the activity of the flat-plate denitration catalyst.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas denitration, and in particular to a flat plate denitration catalyst activity detection system and method. Background Art

[0002] Selective catalytic oxidation reduction (SCR) is the most widely used technology for flue gas denitrification in coal-fired power plants, and the catalyst is the core of SCR technology. At present, the types of commercial SCR catalysts are mainly flat plate and honeycomb, with the main active ingredient being vanadium pentoxide, molybdenum trioxide or tungsten trioxide as an auxiliary agent, and titanium dioxide as a carrier.

[0003] Catalyst activity directly determines denitration performance and is an essential parameter for SCR design. Therefore, the activity value needs to be strictly limited and controlled during the production and use of fresh catalysts. In addition, the activity value usually decreases gradually with the increase of operating time. Therefore, power plants need to test the activity of denitration system catalysts regularly (every six months or one year) and formulate catalyst installation, replacement or regeneration pipeline plans based on the decreasing trend of catalyst activity to ensure safe and stable operation of the unit.

[0004] There are two main types of existing micro flue gas denitration catalyst activity detection devices. One is designed for the denitration performance detection of catalyst powder samples, which is suitable for R&D institutions to improve catalyst formulas, but not for the activity detection of finished catalyst products; the other is designed for the activity detection of block honeycomb catalysts, which can be used for honeycomb catalyst production product quality control and R&D tests, but for the activity test of sheet-shaped flat-plate catalysts, there are problems such as low accuracy and repeatability of the results. In addition, the detection of the activity of flat-plate flue gas denitration catalysts usually uses a pilot device. Due to the large system and complex structure, there are disadvantages such as long testing time and high testing cost, which is not conducive to large-scale sample testing such as production product quality control and R&D tests.

[0005] Therefore, it is necessary to develop a micro-flat plate denitrification catalyst activity detection device and method with simple structure, low cost, good repeatability and strong applicability. Summary of the invention

[0006] The object of the present invention is to provide a system and method for detecting the activity of a flat plate denitration catalyst, which can ensure the accuracy and comparability of the detection results when detecting the activity of the flat plate denitration catalyst.

[0007] The present invention provides a flat plate denitration catalyst activity detection system, comprising:

[0008] A gas supply unit, comprising two or more gas storage devices;

[0009] A gas distribution unit, which includes a control valve arranged at the outlet end of each gas storage device to adjust the flow rate of each gas;

[0010] A reaction unit, comprising a reaction device and a heating device for heating the reaction device, wherein the reaction device is connected to the gas distribution unit and has a reaction chamber for accommodating a flat plate denitration catalyst;

[0011] An analysis unit, comprising a sampling device and a detection device for detecting gas composition, wherein the sampling device has a first sampling port and a second sampling port respectively connected to the front end and the rear end of the flat plate denitration catalyst in the reaction chamber, and the detection device is connected to the outlet end of the sampling device;

[0012] The control unit is electrically connected to the gas distribution unit and the analysis unit respectively. The control unit can control the gas distribution unit according to the information fed back by the analysis unit to adjust the flow rate of each gas.

[0013] In the present invention, the gas supply unit is used to provide a plurality of gases for generating simulated flue gas, that is, a plurality of gases are mixed to form simulated flue gas, and the plurality of gases include but are not limited to nitrogen, oxygen, nitrogen oxides, ammonia, etc., which can be reasonably determined according to actual needs. In one embodiment, the gas supply unit includes a first gas storage device for storing nitrogen, a second gas storage device for storing oxygen, a third gas storage device for storing nitrogen oxides, and a fourth gas storage device for storing ammonia; there is no strict restriction on the structure of the gas storage device, for example, conventional devices such as steel cylinders can be used for gas storage.

[0014] In the present invention, the gas distribution unit is used to accurately control the gas supply pressure, flow rate and other parameters of the various gases provided by the gas supply unit, which can be reasonably determined according to actual needs. In one embodiment, the gas distribution unit also includes a pressure regulating valve arranged at the outlet of each gas storage device to adjust the gas pressure, a flow meter arranged at the outlet of each gas storage device to detect the gas flow rate, and a total flow meter arranged at the total outlet of the gas storage device to detect the total flow rate of each gas. The pressure regulating valve, the flow meter and the total flow meter are electrically connected to the control unit respectively; wherein, the pressure adjustment range of each gas can be 0.3-0.5MPa, and the total flow rate range can be 1-3Nm 3 / h. Under the above setting mode, the gas distribution unit mixes nitrogen, oxygen, nitrogen oxides and ammonia in order to generate simulated flue gas, and the total flow meter accurately controls the total flow of the simulated flue gas.

[0015] The flat-plate denitration catalyst activity detection system of the present invention may also include a pretreatment unit disposed between the gas supply unit and the reaction unit, the pretreatment unit including a mixing device for gas mixing and a preheating device for preheating the gas, the heating device and the preheating device are electrically connected to the control unit respectively. There is no limitation on the specific structure of the mixing device and the preheating device, and conventional structures in the art may be adopted; specifically, the mixing device may be an annular coil, and the preheating device may be a radiation heating shell disposed outside the annular coil. The above-mentioned pretreatment unit can realize the functions of gas mixing and preheating at the same time, wherein the preheating temperature range may be 50-400°C.

[0016] The present invention does not impose strict restrictions on the specific structure of the reaction device. For example, it can be a horizontal reactor. At least one concave card slot for fixing the flat plate denitration catalyst can be arranged in the reaction chamber of the reaction device. There is no strict restriction on the number of concave card slots. For example, it can be set to 5, which can be arranged at intervals between the front end and the rear end of the reaction chamber. This arrangement can realize the detection of the finished flat plate catalyst and ensure the repeatability of the catalyst activity detection.

[0017] In addition, a sample loading port is provided on the side wall of the reaction device, a flange cover is provided on the sample loading port, and a sealing gasket is provided between the flange cover and the sample loading port, and the sealing gasket can be, for example, a graphite gasket, etc. The above arrangement not only has a good sealing effect, but also facilitates the loading and unloading of the sample flat plate denitration catalyst, and the operation is more convenient and safe.

[0018] The heating device is used to heat the reaction device, and there is no strict restriction on its setting mode; specifically, the heating device can be set outside the reaction device, and the heating method of the reaction device can be conventional heating methods such as radiation heating or sheath heating. In one embodiment, the heating device is a cast copper sheath structure, and the heating temperature can be 50-500°C.

[0019] In the present invention, a first temperature sensor for detecting the temperature of the gas at the front end of the flat-plate denitration catalyst, a second temperature sensor for detecting the temperature of the gas at the rear end of the flat-plate denitration catalyst, a pressure sensor for detecting the gas pressure, and a manual valve for controlling the gas pressure are provided on the reaction device, and the first temperature sensor, the second temperature sensor, and the pressure sensor are electrically connected to the control unit, respectively. The first temperature sensor is used to test the actual temperature of the flue gas before the reaction, and the second temperature sensor is used to test the actual temperature of the flue gas after the reaction. During the test, the temperature before and after the reaction reaches the target temperature at the same time, the control accuracy is ±1°C, and the pressure of the reaction unit is 0.1-0.15MPa.

[0020] In the present invention, the analysis unit also includes a filter arranged between the sampling device and the detection device, the sampling device is a three-way solenoid valve, and the detection device includes a Fourier transform infrared analyzer and an oxygen detection device for detecting the oxygen content. The filter is used to filter impurities such as dust in the flue gas; the three-way solenoid valve can switch to connect the analysis unit, so that the detection and analysis of the flue gas components before and after the reaction can be quickly realized to ensure the accuracy of the catalyst activity detection; the Fourier transform infrared analyzer can analyze the nitrogen oxides (nitrogen oxides, nitrogen dioxide, nitrous oxide) and ammonia content in the flue gas at one time; the oxygen detection device can analyze the oxygen content in the flue gas.

[0021] The flat-plate denitration catalyst activity detection system of the present invention further comprises a tail gas treatment unit arranged at the outlet end of the reaction unit, and the tail gas treatment unit comprises an acid adsorption box for adsorbing and treating ammonia and an alkaline adsorption box for adsorbing and treating nitrogen oxides. The tail gas treatment unit can adsorb and treat nitrogen oxides and ammonia in the flue gas, thereby avoiding environmental pollution.

[0022] In the present invention, the control unit is mainly used for the control and adjustment of the flat-plate flue gas denitrification catalyst activity detection system, including the control and adjustment of the flow rate of the gas distribution unit and the simulated flue gas components, the adjustment and control of the temperature of the pretreatment unit, the adjustment and control of the temperature of the reactor heating device, the pressure sensor, the temperature sensor, the detection and display of the test parameters of the flue gas analysis unit, etc. The control unit can accurately adjust the flow rate ratio of each gas component according to the real-time recorded data fed back by the analysis unit, thereby ensuring the accuracy of the detection data to the greatest extent.

[0023] The present invention also provides a method for detecting the activity of a flat-plate denitration catalyst, which is detected by using the above-mentioned flat-plate denitration catalyst activity detection system. The method for detecting the activity of a flat-plate denitration catalyst comprises:

[0024] A flat plate denitration catalyst is placed in a reaction chamber of a reaction device, two or more gases are provided to the reaction device through a gas supply unit, and the flow rate of each gas is adjusted by a gas distribution unit to generate simulated flue gas. The simulated flue gas undergoes a denitration reaction in the reaction chamber, and the gas composition at the front and rear ends of the flat plate denitration catalyst is detected by an analysis unit and fed back to a control unit. The control unit controls the gas distribution unit according to the feedback information to adjust the flow rate of each gas.

[0025] In the flat-plate denitration catalyst activity detection method of the present invention, the pressure of each gas can be controlled to be 0.3-0.5MPa, and the total flow rate of each gas can be controlled to be 1-3Nm 3 / h, the preheating temperature is 50-400°C, the heating temperature of the heating device is 50-500°C, and the pressure of the reaction unit is 0.1-0.15Mpa.

[0026] The implementation of the present invention has at least the following advantages:

[0027] 1. The flat-plate denitration catalyst activity detection system and method of the present invention can accurately adjust the flow ratio of each gas component through a control device according to the data feedback recorded in real time by the flue gas analysis unit, thereby ensuring the accuracy of the data to the greatest extent;

[0028] 2. The flat-plate denitration catalyst activity detection system and method of the present invention standardize the detection process, unify the detection method, equipment and detection conditions, ensure the accuracy and comparability of the detection results, and have the characteristics of simple operation, low cost, good repeatability and strong applicability;

[0029] 3. The flat-plate denitration catalyst activity detection system and method of the present invention can quickly, economically and accurately monitor and test the activity of production samples and research and development samples, distinguish the performance differences of catalysts with different formulations or control the quality of the same batch of catalyst products;

[0030] 4. The flat-plate denitration catalyst activity detection system and method of the present invention can also detect the activity of in-service products, thereby providing data support for power plants to formulate catalyst installation, replacement or regeneration management plans based on the activity decline trend, which can not only meet the production quality monitoring and R&D test of flat-plate catalysts, but also track and detect the after-sales performance of in-service catalysts;

[0031] 5. The flat-plate denitration catalyst activity detection system and method of the present invention can also adsorb nitrogen oxides and ammonia in flue gas, thereby avoiding environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a schematic structural diagram of a flat-plate denitration catalyst activity detection system according to one embodiment of the present invention.

[0034] Description of reference numerals:

[0035] 1: air supply unit; 11: first air storage device; 12: second air storage device; 13: third air storage device; 14: fourth air storage device;

[0036] 2: gas distribution unit; 201: first pressure regulating valve; 202: second pressure regulating valve; 203: third pressure regulating valve; 204: fourth pressure regulating valve; 205: first solenoid valve; 206: second solenoid valve; 207: third solenoid valve; 208: fourth solenoid valve; 209: first flow meter; 210: second flow meter; 211: third flow meter; 212: fourth flow meter; 213: total flow meter;

[0037] 3: pretreatment unit; 31: mixing device; 32: preheating device;

[0038] 4: reaction unit; 41: reaction device; 42: heating device; 43: first temperature sensor; 44: second temperature sensor; 45: pressure sensor; 46: manual valve;

[0039] 5: analysis unit; 51: sampling device; 52: filter; 53: Fourier transform infrared analyzer; 54: oxygen detection device;

[0040] 6: exhaust gas treatment unit; 61: acid adsorption box; 62: alkaline adsorption box;

[0041] 7: Control unit. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0044] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] Example 1

[0046] like Figure 1 As shown, the present embodiment provides a flat-plate denitration catalyst activity detection system, comprising: an air supply unit 1, which comprises more than two gas storage devices; an air distribution unit 2, which comprises a control valve arranged at the outlet end of each gas storage device to adjust the flow rate of each gas; a reaction unit 4, which comprises a reaction device 41 and a heating device 42 for heating the reaction device 41, the reaction device 41 is connected to the air distribution unit 2 and has a reaction chamber for accommodating the flat-plate denitration catalyst; an analysis unit 5, which comprises a sampling device 51 and a detection device for detecting gas composition, the sampling device 51 has a first sampling port and a second sampling port respectively connected to the front end and the rear end of the flat-plate denitration catalyst in the reaction chamber, and the detection device is connected to the outlet end of the sampling device 51; a control unit 7, which is electrically connected to the air distribution unit 2 and the analysis unit 5, respectively, and the control unit 7 can control the air distribution unit 2 according to the information fed back by the analysis unit 5 to adjust the flow rate of each gas.

[0047] The gas supply unit 1 of this embodiment is used to provide a variety of gases for generating simulated flue gas, including but not limited to nitrogen, oxygen, nitrogen oxides, ammonia, etc., which can be reasonably determined according to actual needs. Simulated flue gas is generated after the multiple gases are mixed.

[0048] Specifically, the gas supply unit 1 includes a first gas storage device 11, a second gas storage device 12, a third gas storage device 13 and a fourth gas storage device 14. There is no strict restriction on the structure of each gas storage device. For example, conventional devices such as steel cylinders can be used for gas storage. The first gas storage device 11 is a nitrogen steel cylinder, which is used to generate and simulate nitrogen and other gases that do not participate in the reaction in the flue gas; the second gas storage device 12 is an oxygen steel cylinder, which is used to generate oxygen in the simulated flue gas; the third gas storage device 13 is a nitrogen oxide steel cylinder, which is used to generate and simulate nitrogen oxides in the flue gas; the fourth gas storage device 14 is an ammonia steel cylinder, which is used to generate ammonia in the simulated flue gas.

[0049] In the present invention, the gas distribution unit 2 is used to accurately control the gas supply pressure, flow rate and other parameters of the various gases provided by the gas supply unit 1, and can be reasonably set according to actual needs. In addition to the above-mentioned control valve, the gas distribution unit 2 can also include a pressure regulating valve arranged at the outlet end of each gas storage device to adjust the gas pressure, a flow meter arranged at the outlet end of each gas storage device to detect the gas flow rate, and a total flow meter 213 arranged at the total outlet end of the gas storage device to detect the total flow rate of each gas. The pressure regulating valve, the flow meter and the total flow meter 213 are electrically connected to the control unit 7 respectively. Under the above-mentioned setting mode, the gas distribution unit 2 generates simulated flue gas by mixing and configuring nitrogen, oxygen, nitrogen oxides and ammonia in order, and the total flow meter 213 accurately controls the total flow rate of the simulated flue gas.

[0050] More specifically, the gas distribution unit 2 includes: a first pressure regulating valve 201, i.e., a nitrogen pressure regulating valve, which is used to adjust the nitrogen supply pressure; a second pressure regulating valve 202, i.e., an oxygen pressure regulating valve, which is used to adjust the oxygen supply pressure; a third pressure regulating valve 203, i.e., a nitrogen oxide pressure regulating valve, which is used to adjust the nitrogen oxide supply pressure; a fourth pressure regulating valve 204, i.e., an ammonia pressure regulating valve, which is used to adjust the ammonia supply pressure; a first solenoid valve 205, i.e., a nitrogen solenoid valve, which is used to adjust the opening and cutting of the nitrogen pipeline; a second solenoid valve 206, i.e., an oxygen solenoid valve, which is used to adjust the opening and cutting of the oxygen pipeline ... The third solenoid valve 207, namely the nitrogen oxide solenoid valve, is used to regulate the opening and cutting off of the nitrogen oxide pipeline; the fourth solenoid valve 208, namely the ammonia solenoid valve, is used to regulate the opening and cutting off of the ammonia pipeline; the first flowmeter 209, namely the nitrogen flowmeter, is used to regulate the nitrogen flow rate; the second flowmeter 210, namely the oxygen flowmeter, is used to regulate the oxygen flow rate; the third flowmeter 211, namely the nitrogen oxide flowmeter, is used to regulate the nitrogen oxide flow rate; the fourth flowmeter 212, namely the ammonia flowmeter, is used to regulate the ammonia flow rate; the total flowmeter 213 is used to test the total flue gas flow rate.

[0051] Under the above setting, the gas circuit connection method of nitrogen is as follows: the outlet of the first gas storage device 11 is connected to the first pressure regulating valve 201, and the stability of the gas pressure during the test is ensured by pressure regulation; the first solenoid valve 205 is connected to the first pressure regulating valve 201 and the first flow meter 209 respectively, and the first solenoid valve 205 is opened before the test and disconnected after the test, thereby effectively saving gas consumption and reducing the test cost. The gas circuit connection methods of the other three gases are basically the same as those of nitrogen, and the pressure adjustment range of each gas is 0.3-0.5MPa. At the same time, the outlets of the first flow meter 209, the second flow meter 210, the third flow meter 211, and the fourth flow meter 212 are collected and connected to the total flow meter 213, and the total flow range is 1-3Nm 3 / h.

[0052] The flat-plate denitration catalyst activity detection system of this embodiment also includes a pretreatment unit 3 arranged between the gas supply unit 1 and the reaction unit 4. The pretreatment unit 3 includes a mixing device 31 for gas mixing and a preheating device 32 for preheating the gas. The heating device 42 and the preheating device 32 are electrically connected to the control unit 7 respectively. There is no limitation on the specific structure of the mixing device 31 and the preheating device 32, and conventional structures in the field can be adopted; specifically, the mixing device 31 can adopt an annular coil, and the preheating device 32 can adopt a radiation heating shell. The above-mentioned pretreatment unit 3 is used for the pretreatment of the mixed flue gas at the outlet of the gas distribution unit 2, and can realize the functions of gas mixing and preheating at the same time, wherein the preheating temperature range can be 50-400°C.

[0053] The reaction device 41 is used to implement the denitration reaction of the flue gas. The specific structure of the reaction device 41 is not strictly limited. For example, it can be a horizontal reactor. At least one concave card slot for fixing the flat denitration catalyst can be set in the reaction chamber of the reaction device 41. There is no strict limit on the number of concave card slots. For example, it can be set to 5, which can be set at intervals between the front end and the rear end of the reaction chamber. The above setting method can realize the detection of the finished flat catalyst and ensure the repeatability of the catalyst activity detection.

[0054] In addition, a sample loading port is provided on the side wall of the reaction device 41, a flange cover is provided on the sample loading port, and a sealing gasket is provided between the flange cover and the sample loading port, and the sealing gasket can be, for example, a graphite gasket, etc. The above arrangement not only has a good sealing effect, but also facilitates the loading and unloading of the sample flat plate denitration catalyst, and the operation is more convenient and safe.

[0055] The heating device 42 is used to heat the reaction device 41, and there is no strict restriction on its setting method; specifically, the heating device 42 can be set outside the reaction device 41, and the heating method of the reaction device 41 can be conventional heating methods such as radiation heating or sheath heating. In one embodiment, the heating device 42 is a cast copper sheathed heating structure, and its heating temperature can be 50-500°C.

[0056] In the present invention, a first temperature sensor 43 for detecting the temperature of the gas at the front end of the flat-plate denitration catalyst, a second temperature sensor 44 for detecting the temperature of the gas at the rear end of the flat-plate denitration catalyst, a pressure sensor 45 for detecting the gas pressure, and a manual valve 46 for controlling the gas pressure are provided on the reaction device 41. The first temperature sensor 43, the second temperature sensor 44, and the pressure sensor 45 are electrically connected to the control unit 7, respectively. The first temperature sensor 43 is used to test the actual temperature of the flue gas before the reaction, and the second temperature sensor 44 is used to test the actual temperature of the flue gas after the reaction. During the test, the temperature before and after the reaction should reach the target temperature at the same time, and the accuracy of controlling the temperature before and after the reaction is ±1°C; the manual valve 46 further controls the gas pressure by adjusting the opening, and the pressure of the reaction unit 4 can be 0.1-0.15MPa.

[0057] In the analysis unit 5, the sampling device 51 can use a three-way solenoid valve, which is connected to the front end and the rear end of the catalyst loading position inside the reaction unit 4 through a pipeline, that is, before and after the reaction, and the three-way solenoid valve can be switched to control the extraction of flue gas before or after the reaction. By switching the three-way solenoid valve to connect the analysis unit 5, the detection and analysis of the flue gas components before and after the reaction can be quickly realized, ensuring the accuracy of the catalyst activity detection.

[0058] The analysis unit 5 also includes a filter 52 disposed between the sampling device 51 and the detection device. When the extracted smoke passes through the filter 52, the filter 52 can filter and remove impurities such as dust in the smoke, and then pass the smoke into the detection device for detection. The setting of the filter 52 is conducive to ensuring the accuracy of the detection and prolonging the service life of the detection device.

[0059] The detection device includes a Fourier transform infrared analyzer 53 and an oxygen detection device 54 for detecting the oxygen content; wherein the Fourier transform infrared analyzer 53 can analyze the content of nitrogen oxides (nitrogen oxides, nitrogen dioxide, nitrous oxide) and ammonia in the flue gas at one time, and the oxygen detection device 54 can analyze the content of oxygen in the flue gas.

[0060] The flat-plate denitration catalyst activity detection system of this embodiment further includes an exhaust gas treatment unit 6 disposed at the outlet end of the reaction unit 4, and the exhaust gas treatment unit 6 includes an acid adsorption box 61 for adsorbing and treating ammonia and an alkaline adsorption box 62 for adsorbing and treating nitrogen oxides; there is no strict restriction on the adsorbents filled in the acid adsorption box 61 and the alkaline adsorption box 62, and conventional adsorbents in the art, such as SDG adsorbents, etc., can be used. The exhaust gas treatment unit 6 can adsorb and treat nitrogen oxides and ammonia in the flue gas, thereby avoiding environmental pollution.

[0061] The control unit 7 of this embodiment is mainly used for the control and adjustment of the flat-plate flue gas denitrification catalyst activity detection system, including the control and adjustment of the flow rate and simulated flue gas components of the gas distribution unit 2, the adjustment and control of the temperature of the pretreatment unit 3, the adjustment and control of the temperature of the reactor heating device 42, the first temperature sensor 43, the second temperature sensor 44, the pressure sensor 45, and the detection and display of the test parameters of the analysis unit 5. The control unit 7 can accurately adjust the flow rate ratio of each gas component according to the real-time recorded data fed back by the analysis unit 5, thereby ensuring the accuracy of the detection data to the greatest extent.

[0062] The flat-plate denitrification catalyst activity detection system of the present embodiment can accurately adjust the flow ratio of each gas component through the control unit 7 according to the data feedback recorded in real time by the flue gas analysis unit 5, thereby ensuring the accuracy of the data to the greatest extent; at the same time, the flat-plate denitrification catalyst activity detection system and method standardize the detection process, unify the detection method, equipment and detection conditions, ensure the comparability of the detection results, and have the characteristics of simple operation, low cost, good repeatability, and strong applicability; in addition, the flat-plate denitrification catalyst activity detection system can quickly, economically and accurately monitor and test the activity of production samples and research and development samples, distinguish the performance differences of catalysts with different formulations or the quality control of the same batch of catalyst products, and can also detect the activity of in-service products, thereby providing data support for power plants to formulate catalyst installation, replacement or regeneration management plans according to the activity decline trend, which can not only meet the production quality monitoring and research and development test of flat-plate catalysts, but also track and detect the after-sales performance of in-service catalysts.

[0063] Example 2

[0064] The flat plate denitration catalyst activity detection method of this embodiment adopts the flat plate denitration catalyst activity detection system of embodiment 1 for detection. The flat plate denitration catalyst activity detection method includes:

[0065] A flat plate denitration catalyst is placed in a reaction chamber of a reaction device 41, two or more gases are provided to the reaction device 41 through a gas supply unit 1, and the flow rate of each gas is adjusted by a gas distribution unit 2 to generate simulated flue gas, and the simulated flue gas undergoes a denitration reaction in the reaction chamber, and the gas composition at the front and rear ends of the flat plate denitration catalyst is detected by an analysis unit 5 and fed back to a control unit 7, which controls the gas distribution unit 2 according to the feedback information to adjust the flow rate of each gas.

[0066] In the above-mentioned flat plate denitration catalyst activity detection method, the pressure of each gas can be controlled to be 0.3-0.5MPa, and the total flow rate of each gas can be controlled to be 1-3Nm 3 / h, the preheating temperature is 50-400°C, the heating temperature of the heating device 42 is 50-500°C, and the pressure of the reaction unit 4 is 0.1-0.15Mpa.

[0067] More specifically, the operation process of using the above-mentioned flat-plate denitration catalyst activity detection system for detection is as follows:

[0068] 1. Sample preparation:

[0069] Five samples with a width of 22 mm and a length of 150 mm were cut from the flat flue gas denitration catalyst plate. The dimensions of the samples were measured and recorded before loading, and the surface velocity AV was calculated according to the test conditions.

[0070] 2. Sample loading and unloading:

[0071] Remove the flange cover and the sealing gasket of the reaction device 41, vertically install the above five test samples into the reaction device 41 along the concave slot, and then install the flange cover and the sealing gasket to complete the installation of the flat-plate denitration catalyst test samples.

[0072] 3. Gas supply:

[0073] First, the first gas storage device 11 adjusts the nitrogen pressure to 0.3-0.5 MPa through the first pressure regulating valve 201, opens the first solenoid valve 205 through the control unit 7, and adjusts the first flow meter 209 to pass the amount of nitrogen required for the test to perform an air tightness test.

[0074] Then, the second gas storage device 12, the third gas storage device 13 and the fourth gas storage device 14 are opened through the control unit 7, and the second pressure regulating valve 202, the third pressure regulating valve 203 and the fourth pressure regulating valve 204 are adjusted to make the supply pressure range of each route 0.3-0.5MPa.

[0075] 4. Working condition adjustment:

[0076] Input and adjust the temperature of the preheating device 32 and the heating device 42 in the control unit 7. During the heating process, keep the nitrogen flowing continuously to maintain the uniformity of the temperature field. When the test temperatures of the first temperature sensor 43 and the second temperature sensor 44 reach above 300°C, on the premise of ensuring that the total flowmeter 213 is the target flow, open the second solenoid valve 206, the third solenoid valve 207, and the fourth solenoid valve 208 in the control unit 7 in sequence, and set the theoretically required flow of the second flowmeter 210, the third flowmeter 211, and the fourth flowmeter 212 in sequence. Switch the three-way solenoid valve to sample the flue gas before the reaction, and send it to the analysis unit 5 for detection and analysis. According to the actual concentration or content of oxygen, nitrogen oxides and ammonia, feedback and adjust each flowmeter until the actual concentration or content reaches the target value. Finally, when the temperatures before and after the catalyst reaction measured by the first temperature sensor 43 and the second temperature sensor 44 in the reaction unit 4 reach the target temperature at the same time and stabilize for half an hour, switch the three-way solenoid valve to sample and analyze the flue gas after the reaction. After the concentration or content of each component in the flue gas after the reaction stabilizes for half an hour, read the parameters and complete the test.

[0077] 5. Activity calculation:

[0078] During the test, the readings are taken. The total nitrogen oxide content before the reaction is C1, and the total nitrogen oxide content after the reaction is C2. The denitrification efficiency and activity of the sample are calculated according to the following formula:

[0079] The denitrification efficiency is calculated according to the following formula:

[0080]

[0081] The activity was calculated according to the following formula:

[0082] K = -AV × ln (1-η)

[0083] in:

[0084] η: The value of the denitration efficiency of the catalyst, expressed as a percentage;

[0085] K: The activity value of the catalyst, in meters per hour (m / h);

[0086] AV: The numerical value of surface velocity in meters per hour (m / h).

[0087] The above method was used to test the activity of three groups of flat-plate flue gas denitrification catalyst samples. The test conditions are shown in Table 1, the activity repeatability test results are shown in Table 2, the activity test results of samples produced with different formulas are shown in Table 3, and the activity test results of in-service samples with different operating times are shown in Table 4.

[0088] Table 1 Test conditions

[0089]

[0090] Table 2 Activity repeatability test results

[0091]

[0092] As can be seen from Table 2, three repeatability tests were conducted on the same sample, and the three activity detection results were 44.5 m / h, 44.2 m / h, and 44.5 m / h, respectively, indicating that when the system and method of the present invention are used, the detection results have good repeatability.

[0093] Table 3 Activity test results of samples produced with different formulas

[0094]

[0095] It can be seen from Table 3 that for the production samples with different formulations (different vanadium content and molybdenum content), the variation trend of the activity test results of each sample is consistent with the actual situation, and the activity difference can be accurately distinguished, indicating that when the system and method of the present invention are used, the test results have good accuracy.

[0096] Table 4 Activity test results of in-service samples at different commissioning times

[0097]

[0098] It can be seen from Table 4 that the activity test results of in-service samples with different commissioning times are consistent with the actual situation. This shows that the system and method of the present invention can effectively track the activity change trend of in-service catalysts, thereby providing technical support for the installation, replacement or regeneration management of catalysts in power plant denitrification systems.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flat-plate denitration catalyst activity detection system, characterized in that: include: a gas supply unit comprising a first gas storage device for storing nitrogen, a second gas storage device for storing oxygen, a third gas storage device for storing nitrogen oxides, and a fourth gas storage device for storing ammonia; A gas distribution unit, comprising a control valve arranged at the outlet end of each gas storage device to adjust the flow rate of each gas, a pressure regulating valve arranged at the outlet end of each gas storage device to adjust the gas pressure, a flow meter arranged at the outlet end of each gas storage device to detect the gas flow rate, and a total flow meter arranged at the total outlet end of the gas storage device to detect the total flow rate of each gas, the pressure regulating valve, the flow meter and the total flow meter are electrically connected to the control unit respectively; A reaction unit, comprising a reaction device and a heating device for heating the reaction device, wherein the reaction device is connected to the gas distribution unit and has a reaction chamber for accommodating a flat plate denitration catalyst; A pretreatment unit, which is arranged between the gas supply unit and the reaction unit and includes a mixing device for gas mixing and a preheating device for preheating the gas, the heating device and the preheating device are electrically connected to the control unit respectively; an analysis unit, which includes a sampling device and a detection device for detecting the gas composition, the sampling device has a first sampling port and a second sampling port respectively connected to the front end and the rear end of the flat-plate denitration catalyst in the reaction chamber, and the detection device is connected to the outlet end of the sampling device; The control unit is electrically connected to the gas distribution unit and the analysis unit. The control unit can control the gas distribution unit according to the information fed back by the analysis unit to adjust the flow rate of each gas. The control unit controls the pressure of each gas to 0.3-0.5MPa and the total flow rate of each gas to 1-3Nm 3 / h, the preheating temperature of the preheating device is 50-400°C, the heating temperature of the heating device is 50-500°C, and the pressure of the reaction unit is 0.1-0.15Mpa.

2. The flat-plate denitration catalyst activity detection system according to claim 1, characterized in that: The reaction device is a horizontal reactor, in which a reaction chamber is provided with at least one concave slot for fixing a flat denitration catalyst, a sample loading port is provided on the side wall of the reaction device, a flange cover is provided on the sample loading port, and a sealing gasket is provided between the flange cover and the sample loading port.

3. The flat-plate denitration catalyst activity detection system according to claim 1, characterized in that: The reaction device is provided with a first temperature sensor for detecting the gas temperature at the front end of the flat-plate deNOx catalyst, a second temperature sensor for detecting the gas temperature at the rear end of the flat-plate deNOx catalyst, a pressure sensor for detecting the gas pressure and a manual valve for controlling the gas pressure. The first temperature sensor, the second temperature sensor and the pressure sensor are electrically connected to the control unit respectively.

4. The flat-plate denitration catalyst activity detection system according to claim 1, characterized in that: The analysis unit also includes a filter arranged between the sampling device and the detection device. The sampling device is a three-way electromagnetic valve. The detection device includes a Fourier transform infrared analyzer and an oxygen detection device for detecting oxygen content.

5. The flat-plate denitration catalyst activity detection system according to claim 1, characterized in that: It also includes a tail gas treatment unit arranged at the outlet end of the reaction unit, and the tail gas treatment unit includes an acid adsorption box for adsorbing and treating ammonia and an alkaline adsorption box for adsorbing and treating nitrogen oxides.

6. A method for detecting the activity of a flat plate denitration catalyst, characterized in that: The flat plate denitration catalyst activity detection system according to any one of claims 1 to 5 is used for detection, and the flat plate denitration catalyst activity detection method comprises: A flat plate denitration catalyst is placed in a reaction chamber of a reaction device, two or more gases are provided to the reaction device through a gas supply unit, and the flow rate of each gas is adjusted by a gas distribution unit to generate simulated flue gas. The simulated flue gas undergoes a denitration reaction in the reaction chamber, and the gas composition at the front and rear ends of the flat plate denitration catalyst is detected by an analysis unit and fed back to a control unit. The control unit controls the gas distribution unit according to the feedback information to adjust the flow rate of each gas.

7. The method for detecting the activity of a flat plate denitration catalyst according to claim 6, characterized in that: Control the pressure of each gas to 0.3-0.5MPa, and the total flow rate of each gas to 1-3Nm 3 / h, the preheating temperature is 50-400°C, the heating temperature of the heating device is 50-500°C, and the pressure of the reaction unit is 0.1-0.15Mpa.

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