A nitrogen and oxygen sensor chip for industrial use

Abstract

The invention discloses a nitrogen oxide sensor chip for industry, which relates to the technical field of nitrogen oxide sensors, and comprises a corona component and a zirconia matrix respectively connected to both ends of an air filter element, wherein the corona component is used to perform corona treatment on the air entering the zirconia matrix, so that sulfur dioxide gas in the air forms sulfuric acid aerosol, which is neutralized and absorbed by a solid absorbent contained in the air filter element, so as to reduce the content of harmful gases in the air, protect the zirconia matrix, and make the nitrogen oxide sensor chip suitable for industrial applications. The corona component and the zirconia matrix of the invention are both plugged into the air filter element, and are easy to disassemble and assemble.

Description

Technical Field

[0001] The present invention relates to the technical field of nitrogen oxygen sensors, and in particular to a nitrogen oxygen sensor chip for industry. Background Art

[0002] Existing nitrogen oxide sensor chips are mostly used in the automotive field to monitor the nitrogen oxide content in automobile exhaust. There are few reports on the application of nitrogen oxide sensor chips in industry. Therefore, how to provide a nitrogen oxide sensor chip suitable for industrial applications has become a difficult problem that technicians in this field need to solve urgently. Summary of the invention

[0003] The purpose of the present invention is to provide a nitrogen oxide sensor chip for industrial use, so as to solve the problem that the existing nitrogen oxide sensor chip cannot adapt to various complex industrial environments.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The invention discloses an industrial nitrogen oxygen sensor chip, which comprises a corona component and a zirconium oxide matrix respectively connected to two ends of an air filter component.

[0006] Preferably, the corona element comprises a cylindrical body, a gas discharge electrode is installed inside the cylindrical body, the gas discharge electrode is connected to a high voltage power supply, and the side wall of the cylindrical body is grounded or connected to the neutral line of the power supply; a plug is provided at the air outlet end of the cylindrical body, and the plug is plugged into the air filter element.

[0007] Preferably, the gas discharge electrode comprises a plurality of electrode wires, and the plurality of electrode wires are linear electrode wires or annular electrode wires.

[0008] Preferably, the air filter element includes a purification chamber, and sockets are respectively provided at both ends of the air filter element to communicate with the purification chamber; the plug is plugged into the socket at one end of the air filter element; and the purification chamber is filled with solid absorbent.

[0009] Preferably, the solid absorbent comprises a mixture of one or more of calcium hydroxide, magnesium hydroxide, calcium oxide, zinc oxide and calcium carbonate.

[0010] Preferably, first diffusion barriers are installed at both ends of the purification chamber, and the first diffusion barriers are formed by sintering a mixed slurry consisting of aluminum oxide, zirconium oxide, an oxygen storage agent, a pore-forming agent and a smoothing agent.

[0011] Preferably, the air inlet end of the zirconia substrate is plugged into the socket at the other end of the air filter element, and a limit block is installed on the surface of the zirconia substrate, and the limit block corresponds to the socket on the air filter element.

[0012] Preferably, the zirconia substrate comprises a first zirconia ceramic layer, a second zirconia ceramic layer, a third zirconia ceramic layer, a fourth zirconia ceramic layer, and a fifth zirconia ceramic layer which are stacked in sequence from top to bottom; an air inlet, a first chamber, and a second chamber are provided inside the zirconia substrate between the first zirconia ceramic layer and the third zirconia ceramic layer, the air inlet is arranged side by side and connected to the first chamber and the second chamber, and a second diffusion barrier is provided between the first chamber and the second chamber;

[0013] An oxygen pump is arranged inside the first chamber, and the oxygen pump includes a main pump electrode arranged on the lower surface of the first zirconia ceramic layer and extending into the first chamber, and a common electrode arranged on the upper surface of the first zirconia ceramic layer, and the lower surface of the main pump electrode is in contact with the upper surface of the third zirconia ceramic layer; the main pump electrode is formed by printing a mixed slurry consisting of platinum, gold, zirconium oxide, and a pore-forming agent on the lower surface of the first zirconia ceramic layer and sintering;

[0014] A measuring pump is arranged in the second chamber, and the measuring pump includes a measuring electrode arranged on the upper surface of the third zirconia ceramic layer and extending into the second chamber. The measuring electrode is formed by printing a mixed slurry of platinum, rhodium, zirconium oxide and a pore-forming agent on the upper surface of the third zirconia ceramic layer, and a reference electrode is arranged on the lower surface of the third zirconia ceramic layer.

[0015] Preferably, an auxiliary pump electrode extending into the second chamber is provided on the lower surface of the first zirconia ceramic layer, and the auxiliary pump electrode is formed by printing a mixed slurry of platinum, gold, zirconium oxide and a pore-forming agent on the lower surface of the first zirconia ceramic layer.

[0016] Preferably, a heater is provided between the fourth zirconia ceramic layer and the fifth zirconia ceramic layer.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are:

[0018] The present invention discloses an industrial nitrogen oxide sensor chip, comprising a corona component and a zirconia substrate respectively connected to two ends of an air filter element, wherein the corona component is used to perform corona treatment on air entering the zirconia substrate, so that sulfur dioxide gas in the air forms sulfuric acid aerosol, which is neutralized and absorbed by a solid absorbent contained in the air filter element, so as to reduce the content of harmful gases in the air and protect the zirconia substrate, so that the nitrogen oxide sensor chip is suitable for industrial applications.

[0019] The corona element and the zirconium oxide matrix are both quickly connected to the air filter element in a plug-in manner, and are easy to disassemble and assemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] Figure 1 The structure of the nitrogen and oxygen sensor chip used in industry is shown in FIG. Figure 1 ;

[0022] Figure 2 The structure of the nitrogen and oxygen sensor chip used in industry is shown in FIG. Figure 2 ;

[0023] Figure 3 A partial cross-sectional view of a nitrogen and oxygen sensor chip used in industry according to the present invention;

[0024] Figure 4 It is a schematic diagram of the principle of the zirconium oxide matrix of the present invention.

[0025] Explanation of the reference numerals: 1. corona component; 2. air filter component; 3. zirconia substrate; 101. cylindrical barrel; 102. gas discharge electrode; 103. plug; 201. purification chamber; 202. first diffusion barrier; 301. limit block; 311. first zirconia ceramic layer; 312. second zirconia ceramic layer; 313. third zirconia ceramic layer; 314. fourth zirconia ceramic layer; 315. fifth zirconia ceramic layer; 321. air inlet; 322. first chamber; 323. second chamber; 324. second diffusion barrier; 331. main pump electrode; 332. common electrode; 333. measuring electrode; 334. reference electrode; 335. auxiliary pump electrode; 341. heater. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] like Figure 1-4 As shown, a nitrogen oxygen sensor chip for industrial use includes a corona element 1 and a zirconium oxide substrate 3 respectively connected to two ends of an air filter element 2.

[0028] Specifically, the corona element 1 includes a cylindrical body 101, a gas discharge electrode 102 is installed inside the cylindrical body 101, the gas discharge electrode 102 is connected to a high voltage power supply, and the side wall of the cylindrical body 101 is grounded or connected to the power supply neutral line; a plug 103 is provided at the air outlet end of the cylindrical body 101, and the plug 103 is plugged into the air filter element 2.

[0029] Among them, the power supply modes of the high-voltage power supply include pulse power supply and AC power supply, wherein the voltage of the pulse power supply is ±2kV-±200kV, the pulse repetition frequency is 2Hz-2kHz, and the voltage of the AC power supply is 2kV-200kV, and the frequency is 10Hz-10kHz.

[0030] The cylindrical body 101 has a diameter of 60 mm and a height of 30 mm.

[0031] Specifically, the gas discharge electrode 102 includes a plurality of electrode wires, and the plurality of electrode wires are linear electrode wires or annular electrode wires.

[0032] Specifically, the air filter element 2 includes a purification chamber 201, and sockets are respectively provided at both ends of the air filter element 2 to communicate with the purification chamber 201; the plug 103 is plugged into the socket at one end of the air filter element 2; and the purification chamber 201 is filled with solid absorbent.

[0033] Specifically, the solid absorbent includes a mixture of one or more of calcium hydroxide, magnesium hydroxide, calcium oxide, zinc oxide and calcium carbonate.

[0034] Wherein, the particle size of the solid absorbent is 50 μm-1000 μm.

[0035] Specifically, first diffusion barriers 202 are installed at both ends of the purification chamber 201. The first diffusion barriers 202 are formed by sintering a mixed slurry consisting of aluminum oxide, zirconium oxide, an oxygen storage agent, a pore-forming agent, and a smoothing agent.

[0036] Specifically, the air inlet end of the zirconia substrate 3 is plugged into the socket at the other end of the air filter element 2 , and a limit block 301 is installed on the surface of the zirconia substrate 3 , and the limit block 301 corresponds to the socket on the air filter element 2 .

[0037] Specifically, the zirconia substrate 3 includes a first zirconia ceramic layer 311, a second zirconia ceramic layer 312, a third zirconia ceramic layer 313, a fourth zirconia ceramic layer 314, and a fifth zirconia ceramic layer 315 which are stacked in sequence from top to bottom; an air inlet 321, a first chamber 322, and a second chamber 323 are provided inside the zirconia substrate 3 between the first zirconia ceramic layer 311 and the third zirconia ceramic layer 313, the air inlet 321 is arranged side by side with the first chamber 322 and the second chamber 323 and is connected, and a second diffusion barrier 324 is provided between the first chamber 322 and the second chamber 323;

[0038] An oxygen pump is disposed inside the first chamber 322, and the oxygen pump includes a main pump electrode 331 disposed on the lower surface of the first zirconia ceramic layer 311 and extending into the first chamber 322, and a common electrode 332 disposed on the upper surface of the first zirconia ceramic layer, and the lower surface of the main pump electrode 331 is in contact with the upper surface of the third zirconia ceramic layer 313; the main pump electrode 331 is formed by printing a mixed slurry consisting of platinum, gold, zirconium oxide, and a pore-forming agent on the lower surface of the first zirconia ceramic layer 311 and sintering;

[0039] A measuring pump is provided in the second chamber 323, and the measuring pump includes a measuring electrode 333 provided on the upper surface of the third zirconia ceramic layer 313 and extending into the second chamber 323. The measuring electrode 333 is formed by printing a mixed slurry of platinum, rhodium, zirconium oxide, and a pore-forming agent on the upper surface of the third zirconia ceramic layer 313, and a reference electrode 334 is provided on the lower surface of the third zirconia ceramic layer 313.

[0040] Specifically, an auxiliary pump electrode 335 extending into the second chamber 323 is disposed on the lower surface of the first zirconia ceramic layer 311 . The auxiliary pump electrode 335 is formed by printing a mixed slurry of platinum, gold, zirconium oxide and a pore-forming agent on the lower surface of the first zirconia ceramic layer 311 .

[0041] Specifically, a heater 341 is disposed between the fourth zirconia ceramic layer 314 and the fifth zirconia ceramic layer 315 .

[0042] Connect the corona element 1 and the air filter element 2 together, and detect the sulfur dioxide concentration at the air outlet on the other side of the air filter element 2. The test conditions are as follows:

[0043] Gas flow: 5m 3 / h, the sulfur dioxide concentration at the gas inlet is about 650mg / m 3 , oxygen 9% (volume), water 20% (volume), and the rest nitrogen.

[0044] Solid absorbent: solid calcium hydroxide particles, with a particle size of about 40-250μm.

[0045] Power supply parameters: pulse voltage 40kV, pulse frequency 100Hz, input energy about 20-30W·h / m 3 .

[0046] When the air flow temperature is 20℃, 60℃, 100℃, 120℃ and 160℃, the sulfur dioxide concentration of air filter element 2 and outlet is 35mg / m 3 , 45mg / m 3 , 75mg / m 3 , 120mg / m 3and 280 mg / m 3 .

[0047] The above results show that the corona element 1 and the air filter element 2 do have a filtering effect on sulfur dioxide in the air.

[0048] The corona element 1 and the zirconia substrate 3 are respectively inserted on the left and right sides of the air filter element 2 to obtain an industrial nitrogen oxygen sensor chip, which is compared with the single zirconia substrate 3. The test conditions are the same as the above test conditions. The test stability of fifty industrial nitrogen oxygen sensor chips and fifty zirconia substrates 3 under the same test conditions is measured, and the results are as follows:

[0049] After 6 months, the number of industrial nitrogen oxygen sensor chips with output drift within the preset range was 45, and the number of zirconium oxide substrate 3 with output drift within the preset range was 30. The results show that the industrial nitrogen oxygen sensor chip provided by the present invention is indeed capable of handling industrial working environments.

[0050] The present invention discloses an industrial nitrogen oxide sensor chip, comprising a corona component 1 and a zirconia substrate 3 respectively connected to two ends of an air filter element 2, wherein the corona component 1 is used to perform corona treatment on the air entering the zirconia substrate 3, so that the sulfur dioxide gas in the air forms sulfuric acid aerosol, which is neutralized and absorbed by the solid absorbent contained in the air filter element 2 to reduce the content of harmful gases in the air, thereby protecting the zirconia substrate 3, so that the nitrogen oxide sensor chip is suitable for industrial applications.

[0051] The corona element 1 and the zirconia substrate 3 are both plugged into the air filter element 2, and are easy to assemble and disassemble.

[0052] The use process of the present invention is as follows:

[0053] The nitrogen and oxygen sensor chip is placed at the work site, and the corona element 1 and the zirconia substrate 3 are energized to work. The operation of the zirconia substrate 3 will pump out the oxygen in the first chamber 322 and the second chamber 323. When the first chamber 322 and the second chamber 323 are under negative pressure, the external air will enter the purification chamber 201 from the cylindrical barrel 101 through the plug 103, and then enter the first chamber 322 and the second chamber 323 from the purification chamber 201;

[0054] After the air enters the cylindrical barrel 101, it will be coronaed by the gas discharge electrode 102. After the corona treatment, the sulfur dioxide gas in the air will combine with the moisture and particulate matter in the air to form sulfuric acid aerosol. The sulfuric acid aerosol enters the purification chamber 201 with the airflow and will be neutralized and absorbed by the solid absorbent in the purification chamber 201. The sulfur dioxide component and moisture content in the purified gas are reduced, which can reduce the damage of harmful components in the air to the zirconia substrate 3.

[0055] During the working process of the present invention, the heater 341 performs auxiliary heating, and under high temperature conditions, a voltage is applied between the main pump electrode 331 and the common electrode 332, and the oxygen pump structure composed of the main pump electrode 331 and the common electrode 332 pumps the oxygen in the first chamber 322 out of the chamber. During this process, the nitrogen dioxide in the measuring gas encounters the Pt electrode in the first chamber 322, and a chemical reaction occurs, and the nitrogen dioxide is decomposed into nitric oxide and oxygen.

[0056] In the second chamber 323, a voltage is applied between the auxiliary pump electrode 335 and the common electrode 332 to further reduce the oxygen content in the measuring gas to zero. Under high temperature conditions, the measuring gas contacts the measuring electrode 333 in the second chamber 323. Due to the catalytic effect of platinum and rhodium, a chemical reaction will occur, that is, nitric oxide will decompose into nitrogen and oxygen. Applying a voltage between the measuring electrode 333 and the common electrode 332 will pump all the decomposed oxygen out of the chamber. The process of oxygen ion migration will generate a current IP2. The oxygen content is obtained by the magnitude of the current, and thus the content of nitrogen oxides is obtained.

[0057] It needs to be further explained that the main pump electrode 331 of the present invention is formed by printing a mixed slurry composed of platinum, gold, zirconium oxide, and a pore-forming agent on the lower surface of the first zirconium oxide ceramic layer 311 and sintering. The pore-forming agent will form a pore structure during the sintering process, that is, the main pump electrode 331 of the present invention is a porous structure with countless large and small penetrating air channels formed inside; in the working process of the present invention, the main pump electrode 331 with a porous structure can increase the three-phase interface composed of ZrO2, Pt / Au and exhaust gas by increasing the internal air channels, thereby increasing the contact area between O2 and the catalytic electrode, so as to enhance its ability to catalyze O2, thereby improving the oxygen pumping capacity of the main pump electrode 331 and achieving the effect of providing measurement accuracy.

[0058] It needs further explanation that, since corona treatment of air will produce additional nitrogen oxides, when calculating the nitrogen oxide content in the air, a constant value needs to be subtracted from the current IP2.

[0059] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0060] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A nitrogen oxygen sensor chip for industrial use, characterized in that: It comprises a corona element (1) and a zirconium oxide substrate (3) respectively connected to two ends of an air filter element (2); The corona element (1) comprises a cylindrical body (101), a gas discharge electrode (102) is installed inside the cylindrical body (101), the gas discharge electrode (102) is connected to a high-voltage power supply, and the side wall of the cylindrical body (101) is grounded or connected to the neutral line of the power supply; a plug (103) is provided at the air outlet end of the cylindrical body (101), and the plug (103) is plugged into the air filter element (2); The air filter element (2) comprises a purification chamber (201); both ends of the air filter element (2) are provided with sockets respectively connected to the purification chamber (201); the plug (103) is plugged into the socket at one end of the air filter element (2); the purification chamber (201) is filled with a solid absorbent; The solid absorbent comprises a mixture of one or more of calcium hydroxide, magnesium hydroxide, calcium oxide, zinc oxide and calcium carbonate; The zirconia substrate (3) comprises a first zirconia ceramic layer (311), a second zirconia ceramic layer (312), a third zirconia ceramic layer (313), a fourth zirconia ceramic layer (314), and a fifth zirconia ceramic layer (315) which are stacked in sequence from top to bottom; an air inlet (321), a first chamber (322), and a second chamber (323) are provided inside the zirconia substrate (3) between the first zirconia ceramic layer (311) and the third zirconia ceramic layer (313); the air inlet (321) is arranged side by side with and communicated with the first chamber (322) and the second chamber (323); a second diffusion barrier (324) is provided between the first chamber (322) and the second chamber (323); An oxygen pump is arranged inside the first chamber (322), and the oxygen pump comprises a main pump electrode (331) arranged on the lower surface of the first zirconia ceramic layer (311) and extending into the first chamber (322), and a common electrode (332) arranged on the upper surface of the first zirconia ceramic layer, the lower surface of the main pump electrode (331) is in contact with the upper surface of the third zirconia ceramic layer (313); the main pump electrode (331) is formed by printing a mixed slurry consisting of platinum, gold, zirconium oxide, and a pore-forming agent on the lower surface of the first zirconia ceramic layer (311) and sintering; A measuring pump is arranged in the second chamber (323), and the measuring pump comprises a measuring electrode (333) arranged on the upper surface of the third zirconia ceramic layer (313) and extending into the second chamber (323); the measuring electrode (333) is formed by printing a mixed slurry of platinum, rhodium, zirconium oxide and a pore-forming agent on the upper surface of the third zirconia ceramic layer (313); and a reference electrode (334) is arranged on the lower surface of the third zirconia ceramic layer (313).

2. The industrial nitrogen oxygen sensor chip according to claim 1, characterized in that: The gas discharge electrode (102) comprises a plurality of electrode wires, wherein the plurality of electrode wires are linear electrode wires or annular electrode wires.

3. The industrial nitrogen oxygen sensor chip according to claim 1, characterized in that: A first diffusion barrier (202) is installed at both ends of the purification chamber (201), wherein the first diffusion barrier (202) is formed by sintering a mixed slurry consisting of aluminum oxide, zirconium oxide, an oxygen storage agent, a pore-forming agent, and a smoothing agent.

4. The industrial nitrogen oxygen sensor chip according to claim 1, characterized in that: The air inlet end of the zirconia substrate (3) is plugged into the other end socket of the air filter element (2), and a limit block (301) is installed on the surface of the zirconia substrate (3), and the limit block (301) corresponds to the socket on the air filter element (2).

5. The industrial nitrogen and oxygen sensor chip according to claim 1, characterized in that: An auxiliary pump electrode (335) extending into the second chamber (323) is provided on the lower surface of the first zirconia ceramic layer (311); the auxiliary pump electrode (335) is formed by printing a mixed slurry of platinum, gold, zirconium oxide and a pore-forming agent on the lower surface of the first zirconia ceramic layer (311).

6. The industrial nitrogen oxygen sensor chip according to claim 1, characterized in that: A heater (341) is provided between the fourth zirconia ceramic layer (314) and the fifth zirconia ceramic layer (315).

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