CN114832624A - Tail gas purification method and system for diesel vehicle emission inspection mechanism - Google Patents
Tail gas purification method and system for diesel vehicle emission inspection mechanism Download PDFInfo
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- B01D53/34—Chemical or biological purification of waste gases
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- B01D53/34—Chemical or biological purification of waste gases
- B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
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- B01D53/9404—Removing only nitrogen compounds
- B01D53/9409—Nitrogen oxides
- B01D53/9413—Processes characterised by a specific catalyst
- B01D53/9418—Processes characterised by a specific catalyst for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas
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- B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
- B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
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Abstract
The invention discloses a method and a system for purifying tail gas of a diesel vehicle emission inspection mechanism, which are applied to the technical field of motor vehicle tail gas treatment and record vehicle information; driving a negative pressure fan to extract tail gas of a vehicle, carrying out flow acquisition, heating to the optimal working temperature of a catalyst and carrying out purification treatment; and judging whether the purified tail gas meets the purification standard or not, and if not, carrying out heating and purification again. The invention discloses a method and a system for purifying tail gas of a diesel vehicle emission inspection mechanism, which realize the following purification of tail gas emission of a motor vehicle along with detection.
Description
Technical Field
The invention relates to the technical field of motor vehicle tail gas treatment, in particular to a tail gas purification method and a system for a diesel vehicle emission inspection mechanism.
Background
At present, an effective tail gas purification system is not equipped in a diesel vehicle emission inspection mechanism, and the diesel vehicle is directly extracted and exhausted to the atmosphere through a pumping and exhausting system.
In order to reduce the influence of automobile exhaust on the environment in the process of diesel vehicle emission inspection, partial inspection mechanisms adopt various exhaust purification means to ensure that the environment in an inspection station is prevented from being polluted. For example, a forced pumping system is adopted in part of detection stations to pump out automobile exhaust in the detection stations, and activated carbon is adopted in part of detection stations to adsorb gaseous pollutants. Because the mode does not purify the tail gas or the purifying effect is not ideal, the pollution of the tail gas to the atmospheric environment cannot be effectively prevented.
Therefore, how to perform rapid centralized collection and efficient purification treatment on the exhaust gas discharged in the vehicle detection process, and control and purify the exhaust pollution generated in the motor vehicle emission inspection mechanism in real time is a problem to be solved urgently at present.
Disclosure of Invention
In view of the above, the present invention provides a method and a system for purifying exhaust gas from a diesel vehicle emission inspection mechanism, which can perform rapid centralized collection and efficient purification treatment on exhaust gas discharged during a vehicle inspection process, and can control and purify exhaust gas pollution generated in the motor vehicle emission inspection mechanism in real time.
In order to achieve the above purpose, the invention provides the following technical scheme:
a tail gas purification method for a diesel vehicle emission inspection mechanism comprises the following specific steps:
vehicle information is input;
driving a negative pressure fan to extract tail gas of a vehicle, carrying out flow acquisition, heating to the optimal working temperature of a catalyst and carrying out purification treatment;
and judging whether the purified tail gas meets the purification standard or not, and if not, carrying out heating and purification again.
Optionally, in the method for purifying exhaust gas from an emission inspection mechanism of a diesel vehicle, the purification treatment includes:
oxidizing carbon monoxide, hydrocarbons and soluble organic matters in the tail gas by an oxidation catalytic converter to generate carbon dioxide and water;
the tail gas after oxidation treatment enters a particle catcher for filtration to remove soot particulate matters;
the urea solution enters a selective catalytic reducer, and a control unit controls the spraying amount of the urea solution according to the flow rate of the tail gas to be purified, the content of nitrogen oxides and the conversion efficiency of the selective catalytic reducer so as to reduce the nitrogen oxides in the tail gas into nitrogen and water; unreacted ammonia gas in the selective catalytic reduction device is absorbed and treated by an ammonia escape catalyst, and NH is catalyzed again 3 、NO x The reaction was nitrogen.
Optionally, in the method for purifying exhaust gas from an emission testing mechanism of a diesel vehicle, the heating treatment includes: collecting the inlet temperature of a heating device and displaying the temperature state, adjusting the heating power to control heating, determining the heating temperature of the heating device according to the monitoring temperature of a temperature sensor before SCR, enabling the carrier temperature and the exhaust temperature in a subsequent purification device to reach the optimal working temperature of a catalyst, if the carrier temperature and the exhaust temperature do not reach the optimal working temperature, continuing to control heating, and controlling in a circulating manner until a purification system stops operating.
Optionally, in the method for purifying exhaust gas from an emission testing mechanism of a diesel vehicle, the method further includes: the particle catcher regeneration step comprises the following specific steps:
acquiring the change of the pressure difference before and after the particle catcher is purified;
when the pressure drop at two ends of the particle catcher is larger than the upper limit threshold value, the purification work is stopped, and the regeneration is started;
in the regeneration temperature rising stage of the particle catcher, whether the peak temperature of the wall surface of the particle catcher reaches the lowest regeneration particle catcher temperature or whether the peak temperature of the wall surface of the particle catcher reaches the damage temperature of the carrier of the particle catcher is obtained;
if the lowest regeneration temperature is not reached to 600 ℃ or is higher than 700 ℃, continuing to adjust the heating power and the diluted exhaust flow until the regeneration requirement is met;
in the regeneration temperature maintaining stage of the particle catcher, a pressure difference sensor at two ends of the particle catcher continuously monitors whether the pressure drop is smaller than a regeneration threshold value, and the circulation control is carried out until the regeneration is stopped.
Optionally, in the method for purifying exhaust gas from an emission testing mechanism of a diesel vehicle, the step of controlling the injection amount of the urea aqueous solution specifically comprises the following steps:
the controller sends a motor start command, a pump state command, a diagnostic instrument command start confirmation, and NO x Confirming the opening of the dew point enable of the sensor and manually controlling the opening instruction of the urea nozzle;
and (4) the urea pump enters a pre-injection state, urea injection amount is given according to the concentration and the flow of the oxynitride, and finally pump information is fed back and output.
Optionally, in the method for purifying exhaust gas from an emission testing mechanism of a diesel vehicle, the calculation process of the urea injection amount according to the concentration and flow of the oxynitride is as follows:
wherein, V S Volume flow m under standard exhaust gas conditions 3 /min；NO x Nitrogen oxygen concentration, ppm; m urea Urea injection amount; δ is the physical conversion efficiency; 22.4L/mol is the gas molar volume of the gas under the standard condition, and 60g/mol is the urea molar mass; 0.325 is the concentration of urea aqueous solution; 1.087 is the density of the aqueous urea solution.
The utility model provides a diesel vehicle discharges inspection mechanism tail gas clean-up system, includes:
the tail gas collection and flow measurement module is used for driving the negative pressure fan to obtain tail gas discharge amount and providing a flow numerical value in a standard state for the subsequent tail gas purification module;
the tail gas heating module is used for heating the tail gas of the diesel vehicle by adopting electric heating to meet the optimal catalytic temperature value of a catalyst in the tail gas purification module;
the tail gas purification module treats CO, HC, SOF and NO in tail gas through DOC + DPF + SCR + ASC x And soot harmful substances;
and the control module respectively controls the tail gas collecting and flow measuring module, the tail gas heating module and the tail gas purifying module to act.
Optionally, in the exhaust gas purification system of the diesel vehicle emission inspection mechanism, the system further includes a DPF regeneration module, and the DPF regeneration is performed by adjusting the heating power and the diluted exhaust flow.
Compared with the prior art, the invention discloses and provides the method and the system for purifying the tail gas of the diesel vehicle emission inspection mechanism, so that the tail gas of the motor vehicle is purified along with detection, in addition, the regeneration mode adopted when the DPF is blocked adopts a negative pressure fan and a heating device in a measurement module, the carbon smoke is removed with very small air quantity and very high temperature, and the regeneration of the DPF is realized by controlling the flow and the temperature.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a flow chart of a method of the present invention;
FIG. 2 is a flow diagram of a self-test of the purification system of the present invention;
FIG. 3 is a flow chart of the temperature maintenance of the heating device according to the present invention;
FIG. 4 is a flow chart of DPF regeneration according to the present invention;
FIG. 5 is a pressure build-up flow diagram of a urea pump according to the present invention
FIG. 6 is a flow diagram of a urea pump injection of the present invention;
FIG. 7 is a schematic view of the structure of the purification apparatus of the present invention.
In the figure, 1-negative pressure fan; 2-a flow meter; 3-a pipe heater; 4-tail gas conveying pipe; 5-a catalytic converter (DOC); 6-particulate trap (DPF); a 7-Selective Catalytic Reduction (SCR); 8-Ammonia Slip Catalyst (ASC); 9-a pre-nitroxide sensor; 10-a post-nitroxide sensor; 11-a temperature sensor; 12-a differential pressure sensor; 13-a urea tank; 14-a urea pump; 15-urea nozzle.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment of the invention discloses a method for purifying tail gas of a diesel vehicle emission inspection mechanism, which comprises the following specific steps as shown in figures 1 and 7:
the exhaust gas purification system of the diesel vehicle emission inspection mechanism treats the diesel vehicle emission detection items in the detection station, so the start of the exhaust gas emission detection is the start of purification. Before the tail gas detection purifies begins, wait to examine vehicle information input and accomplish the back, the vehicle drives into chassis dynamometer machine, and inside the operator put into the exhaust pipe with tail gas analysis appearance sampling probe, prepare the work in earlier stage and accomplish the back, can carry out tail gas detection, tail gas purification begins simultaneously. Controlling the speed of the vehicle by a vehicle pilot, loading a chassis dynamometer and starting measurement; meanwhile, the purification system is also in a working state, a tail gas collecting pipe of the purification system and an exhaust pipe of the detected vehicle are arranged on the same axis, an air inlet of the tail gas collecting pipe is 15-20 cm away from the exhaust pipe of the detected vehicle, a variable frequency motor is started to drive a negative pressure fan, the tail gas of the detected vehicle flows through a V-cone flowmeter and is extracted to a heating device for electric heating treatment, and the tail gas reaches the optimal working temperature (about 280 ℃) of a catalyst in a subsequent purification device. Then, the exhaust enters a motor vehicle purification device for purification treatment, and harmful gases (mainly carbon monoxide (CO), Hydrocarbons (HC), soluble organic matters (SOF) and the like) in the exhaust are oxidized by an oxidation catalytic converter (DOC) to generate carbon dioxide (CO) 2 ) And water (H) 2 O). The tail gas after oxidation treatment enters a particle trap (DPF) for filtration to remove particulate matters such as soot and the like, and then enters a Selective Catalytic Reduction (SCR), and a control unit controls the flow rate and Nitrogen Oxides (NO) according to the tail gas to be purified x ) The content and the SCR conversion efficiency are used for controlling the spraying amount of the urea aqueous solution and converting Nitrogen Oxide (NO) in the tail gas x ) Reduction to nitrogen (N) 2 ) And water (H) 2 O). Unreacted ammonia (NH) in a Selective Catalytic Reduction (SCR) reactor 3 ) Is absorbed and treated by an Ammonia Slip Catalyst (ASC) and simultaneously catalyzes NH 3 、NO x The reaction is nitrogen (N) 2 ). Catalyst for ammonia escape(ASC) having NO collection provided at the outlet x And a sensor for detecting the content of the pollutants, wherein the sensor is used for monitoring whether the purified tail gas reaches the purification standard or not, and the treated tail gas and moisture are discharged from a gas outlet of the purification device, so that the aims of purifying the environment around the diesel vehicle emission inspection mechanism and ensuring the health of workers and surrounding residents are fulfilled.
In order to further optimize the above technical solution, as shown in fig. 2, in order to ensure the smooth proceeding of the purification process of the exhaust gas purification system of the emission inspection mechanism, the system itself is first self-tested before purification. After the purification system is electrified and initialized, firstly, an instruction is sent through the CAN bus, namely whether the communication function of the CAN bus of the purification system is normal or not is detected. And the blower CAN be started after the CAN bus communication function is normal, and whether the functions of the blower and the diluted tail gas flow sensor are normal or not is judged in sequence. And then, an instruction can be sent to detect a temperature sensor, the temperature sensor is mainly used for monitoring the diluted exhaust temperature, after the temperature sensor is judged to work normally, a heating device is started to judge whether the heating function of the heating device is normal, heating power is adjusted according to the temperature monitored by the temperature sensor before SCR to control heating, when the exhaust temperature monitored by the temperature sensor before SCR is higher than 280 ℃, the temperature of each carrier catalyst of DOC, DPF, SCR and ASC is met, the temperature for effective reaction of ammonia gas and NOx generated by high-temperature hydrolysis of urea is met, then whether the functions of the nitrogen oxygen sensor and the pressure sensor are normal is judged, and after each sensor has no fault, a urea pump motor can be started to sequentially judge whether the pressure building function and the suck-back function of the urea pump are normal. In the self-checking process of the whole system, if any one function of the purification system is abnormal, all detections are stopped and a fault alarm signal is sent out. And finally, storing a system self-checking result.
In order to further optimize the above technical solution, as shown in fig. 3, the heating process includes: the main function of the temperature maintenance of the heating device is to continuously and stably maintain the tail gas of the diesel vehicle at the optimal catalytic temperature of the purification device. After the purification system is electrified and initialized, a heating function program of the heating device is started, then the temperature is preset, the inlet temperature of the heating device is collected, the temperature state is displayed, the heating power is adjusted to control heating, whether the front temperature of the SCR meets the target temperature or not is judged, if not, the heating is continuously controlled, and the circulation control is carried out until the purification system stops running.
In order to further optimize the above technical solution, as shown in fig. 4, the method further includes: the particle catcher regeneration step comprises the following specific steps:
when the purification system of the diesel vehicle emission inspection mechanism is in a working state, the differential pressure sensor of the purification device constantly monitors the change of the front and back differential pressure of the DPF, and when the pressure drop at two ends of the DPF is larger than an upper limit threshold value (15kPa), the lower computer sends an alarm signal, stops purification work and executes a regeneration program. After the DPF regeneration program is started, the heating device and the fan are started, and the regeneration temperature is stably increased by adjusting the heating power and the diluted exhaust flow. In the regeneration temperature rising stage of the DPF, a temperature sensor continuously monitors whether the peak temperature of the wall surface of the DPF reaches a regeneration temperature range (600 ℃ -700 ℃), and as the carbon smoke particles attached to the carrier in the regeneration stage of the DPF release a large amount of heat due to combustion, the DPF carrier is damaged due to overheating of the temperature, if the minimum regeneration temperature is not reached or the damage temperature of the carrier is exceeded, the heating power and the flow rate of the diluted exhaust gas are continuously adjusted until the regeneration requirement is met. And then entering a DPF regeneration temperature maintaining stage, and continuously monitoring whether the pressure drop across the DPF is smaller than a regeneration threshold value (3kPa) by a pressure difference sensor, so as to circularly control until the regeneration program stops running. In order to further optimize the technical scheme, as shown in fig. 5, after the tail gas purification system of the diesel vehicle emission inspection mechanism is electrified and initialized, the self-inspection of the urea pump is finished, the system has no fault, and the exhaust temperature after dilution is higher than 180 ℃. And then, the pump controller sends a frame of CAN message to the urea pump, the urea pump enters a pressure building state, the urea nozzle is closed, and the urea solution flows in from the liquid inlet pipe of the urea tank assembly. And then, detecting the pressure of the urea pump, and when the pressure of the urea pump is more than or equal to 5.5bar and the pressure building time is less than or equal to 35s, indicating that the pressure building of the urea pump is successful, stopping the urea pump from rotating, otherwise, performing cycle control until the pressure building of the urea pump system is successful.
In order to further optimize the above technical solution, as shown in fig. 6, the specific steps of controlling the injection amount of the urea aqueous solution are as follows:
after the urea pump builds the pressure successfully, the pump receives that the controller meets the injection instruction, and the urea pump enters the injection state. Pump control sending motor on command, pump status command, diagnostic instrument command on confirmation, NO x The method comprises the steps of enabling opening confirmation of a sensor dew point, manually controlling an opening instruction of a urea nozzle and the like, enabling a urea pump to enter a pre-injection state, further entering an injection state, giving urea injection quantity, and finally feeding back and outputting pump information, wherein the pump information mainly comprises information such as pump pressure, nozzle opening, actual injection quantity, pump actual state and the like.
It should be appreciated that the urea injection quantity relationship is determined: hydrolyzing 1mol of urea at high temperature to generate 2mol of NH 3 ，NH 3 With NO x The reaction ratio of (A) to (B) is 1: 1.
In order to further optimize the technical scheme, the calculation process of the given urea injection quantity according to the concentration and the flow of the oxynitride is as follows:
wherein, V S Volume flow m under standard exhaust gas conditions 3 /min；NO x Nitrogen oxygen concentration, ppm; m urea Urea injection amount; δ is the physical conversion efficiency; 22.4L/mol is the gas molar volume of the gas under the standard condition, and 60g/mol is the urea molar mass; 0.325 is the concentration of urea aqueous solution; 1.087 is the density of the aqueous urea solution.
Another embodiment discloses a diesel vehicle discharges inspection mechanism tail gas clean-up system, includes:
the tail gas collecting and flow measuring module is used for driving the negative pressure fan to obtain tail gas discharge and providing a flow numerical value in a standard state for the subsequent tail gas purification module;
the tail gas heating module is used for heating the tail gas of the diesel vehicle by adopting electric heating to meet the optimal catalytic temperature value of a catalyst in the tail gas purification module;
the tail gas purification module treats CO, HC, SOF and NO in tail gas through DOC + DPF + SCR + ASC x And soot harmful substances;
and the control module respectively controls the tail gas collecting and flow measuring module, the tail gas heating module and the tail gas purifying module to act.
In order to further optimize the technical scheme, the device further comprises a DPF regeneration module, and DPF regeneration is carried out by adjusting the heating power and the diluted exhaust flow.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (8)
1. The tail gas purification method for the diesel vehicle emission inspection mechanism is characterized by comprising the following specific steps of:
vehicle information is input;
driving a negative pressure fan to extract tail gas of a vehicle, carrying out flow acquisition, heating to the optimal working temperature of a catalyst and carrying out purification treatment;
and judging whether the purified tail gas meets the purification standard or not, and if not, carrying out heating and purification again.
2. The method for purifying the exhaust gas of the diesel vehicle emission testing mechanism according to claim 1, wherein the purification treatment comprises:
firstly, oxidizing carbon monoxide, hydrocarbon and soluble organic matters in tail gas by an oxidation catalytic converter to generate carbon dioxide and water;
the tail gas after oxidation treatment enters a particle catcher for filtration to remove soot particulate matters;
the urea solution enters a selective catalytic reducer, and a control unit controls the spraying amount of the urea solution according to the flow rate of the tail gas to be purified, the content of nitrogen oxides and the conversion efficiency of the selective catalytic reducer so as to reduce the nitrogen oxides in the tail gas into nitrogen and water; unreacted ammonia gas in the selective catalytic reduction device is absorbed and treated by an ammonia escape catalyst, and NH is catalyzed again 3 、NO x The reaction was nitrogen.
3. The method as claimed in claim 1, wherein the heating treatment comprises: collecting the inlet temperature of a heating device and displaying the temperature state, adjusting the heating power to control heating, determining the heating temperature of the heating device according to the monitoring temperature of a temperature sensor before SCR, enabling the carrier temperature and the exhaust temperature in a subsequent purification device to reach the optimal working temperature of a catalyst, if the carrier temperature and the exhaust temperature do not reach the optimal working temperature, continuing to control heating, and controlling in a circulating manner until a purification system stops operating.
4. The method for purifying the exhaust gas of the diesel vehicle emission testing mechanism according to claim 2, further comprising: the particle catcher regeneration step comprises the following specific steps:
acquiring the change of the pressure difference before and after the particle catcher is purified;
when the pressure drop at the two ends of the particle catcher is larger than the upper limit threshold value, the purification work is stopped, and the regeneration is started;
in the regeneration temperature rising stage of the particle catcher, whether the peak temperature of the wall surface of the particle catcher reaches the lowest regeneration particle catcher temperature or whether the peak temperature of the wall surface of the particle catcher reaches the damage temperature of the carrier of the particle catcher is obtained;
if the lowest regeneration temperature is not reached to 600 ℃ or is higher than 700 ℃, continuing to adjust the heating power and the diluted exhaust flow until the regeneration requirement is met;
in the regeneration temperature maintaining stage of the particle catcher, a pressure difference sensor at two ends of the particle catcher continuously monitors whether the pressure drop is smaller than a regeneration threshold value, and the circulation control is carried out until the regeneration is stopped.
5. The method for purifying the tail gas of the diesel vehicle emission inspection mechanism according to claim 2, wherein the step of controlling the injection amount of the urea aqueous solution comprises the following steps:
the controller sends a motor start command, a pump state command, a diagnostic instrument command start confirmation, and NO x Confirming the opening of the dew point enable of the sensor and manually controlling the opening instruction of the urea nozzle;
and (4) the urea pump enters a pre-injection state, urea injection amount is given according to the concentration and the flow of the oxynitride, and finally pump information is fed back and output.
6. The method as claimed in claim 2, wherein the calculation of the urea injection amount based on the concentration and flow rate of nitrogen oxide is as follows:
wherein, V S Volume flow m under standard exhaust gas conditions 3 /min；NO x Nitrogen oxygen concentration, ppm; m urea Urea injection amount; δ is the physical conversion efficiency; 22.4L/mol is the gas molar volume of the gas under the standard condition, and 60g/mol is the urea molar mass; 0.325 is the concentration of urea aqueous solution; 1.087 is the density of the aqueous urea solution.
7. The utility model provides a diesel vehicle discharges inspection mechanism tail gas clean-up system which characterized in that includes:
the tail gas collecting and flow measuring module is used for driving the negative pressure fan to obtain tail gas discharge and providing a flow numerical value in a standard state for the subsequent tail gas purification module;
the tail gas heating module is used for heating the tail gas of the diesel vehicle by adopting electric heating to meet the optimal catalytic temperature value of a catalyst in the tail gas purification module;
the tail gas purification module treats CO, HC, SOF and NO in tail gas through DOC + DPF + SCR + ASC x And soot harmful substances;
and the control module respectively controls the tail gas collecting and flow measuring module, the tail gas heating module and the tail gas purifying module to act.
8. The exhaust gas purification system for diesel vehicle emission testing mechanism according to claim 7, further comprising a DPF regeneration module for performing DPF regeneration by adjusting heating power and diluted exhaust flow.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210425160.5A CN114832624A (en) | 2022-04-22 | 2022-04-22 | Tail gas purification method and system for diesel vehicle emission inspection mechanism |
| ZA2022/11038A ZA202211038B (en) | 2022-04-22 | 2022-10-10 | Method and system for purifying exhaust of diesel vehicle emission inspection institution |
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| CN202210425160.5A CN114832624A (en) | 2022-04-22 | 2022-04-22 | Tail gas purification method and system for diesel vehicle emission inspection mechanism |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116165350A (en) * | 2023-03-13 | 2023-05-26 | 山东交通学院 | Method, system and equipment for detecting pollutants of diesel vehicle based on remote sensing technology |
| CN116446985A (en) * | 2023-06-14 | 2023-07-18 | 山东鼎昌智能科技有限公司 | Automobile urea box capable of automatically controlling urea liquid supply |
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| ZA202211038B (en) | 2022-12-21 |
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