A urea detection method, device and system applied to an aftertreatment system

Abstract

The application discloses a urea detection method, device and system applied to a post-processing system, and belongs to the field of diesel engine post-processing systems. The method is: acquiring a urea quality value and a urea consumption value; when a urea quality alarm threshold is reached, an alarm signal is generated and is forwarded to a cloud platform server, and the urea consumption value is synchronously and continuously uploaded; based on the alarm signal, a urea injection valve is opened; after the urea injection valve is opened, a nitrogen oxide concentration value is acquired; if the nitrogen oxide concentration value reaches a preset nitrogen oxide threshold, a three-way electromagnetic valve sampling is started and a urea pump is started; after the three-way electromagnetic valve sampling reaches a preset time, the sampling is stopped and the urea pump is synchronously closed, and urea sampling is marked as a full bottle state; based on the full bottle state, a sampling signal is generated, which is used for sending a sample of urea in a sampling bottle to a laboratory to determine whether low-quality urea is qualified. The application automatically controls urea sampling starting, and realizes high-precision and real-time detection of the quality of urea and urea consumption.

Description

Technical Field

[0001] The present invention belongs to the field of non-road diesel engine after-treatment systems, and in particular relates to a urea detection method, device and system applied to the after-treatment system. Background Art

[0002] The after-treatment system includes a DOC system, a DPF system, and an SCR system. The main function of the SCR system is to reduce ammonia with nitrogen oxides in the engine exhaust under the action of a catalyst to produce harmless ammonia and water. Among them, the urea solution in the urea tank is sprayed into the SCR system through a urea nozzle, and the urea dissolves and undergoes a thermal decomposition reaction to produce ammonia; in this process, the urea consumption of the after-treatment system should be proportional to the content of pollutants emitted by the engine. If the urea consumption is abnormal, it may cause the emission of pollutants to exceed the standard or due to a malfunction of the after-treatment system. Therefore, in order to reduce harmful gases in exhaust emissions and whether the after-treatment system is operating normally, it is necessary to detect the urea consumption of the after-treatment system to avoid excessive or low consumption.

[0003] Secondly, long-term use of low-quality urea will lead to reduced conversion efficiency of the SCR system and increased urea consumption. However, traditional urea quality sensors are not accurate enough and may cause false alarms. In addition, urea replacement frequency is high, and sampling is time-consuming and labor-intensive. Although existing diesel engine aftertreatment systems can detect urea consumption, such as determining whether urea injection is normal by collecting urea injection duration and preset injection duration, and then further judging urea consumption by the injection performance of the urea solution; another method is to calculate urea consumption from the nitrogen oxide signal of the NOx sensor, and then further calculate the urea-fuel ratio, and judge whether urea consumption is abnormal based on the set urea consumption; in addition, there is a technology that determines whether urea consumption is abnormal based on the urea injection volume. Although the above three methods can detect urea consumption to a certain extent, they cannot achieve high-precision detection of urea quality. Therefore, the performance of the aftertreatment system cannot be comprehensively and effectively evaluated based on the urea consumption test results alone. Summary of the Invention

[0004] The object of the present invention is to provide a urea detection method, device and system for a post-treatment system, which can solve the problems in the background technology. By collecting urea mass values ​​and urea consumption values ​​for comprehensive judgment and uploading the data to a cloud platform, the urea consumption and urea quality are further continuously calculated and monitored, and the urea sampling start is automatically controlled to achieve high-precision detection of urea quality and urea consumption at the same time.

[0005] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions.

[0006] In one aspect, the present invention provides a urea detection method for a post-treatment system, comprising:

[0007] Obtain urea mass value and urea consumption value;

[0008] When the urea quality value reaches the urea quality alarm threshold, an alarm signal is generated and forwarded to the cloud platform server, and the urea consumption value is synchronously and continuously uploaded;

[0009] Based on the alarm signal, the urea injection valve is opened;

[0010] When the urea injection valve is opened, the nitrogen oxide concentration value is obtained;

[0011] If the nitrogen oxide concentration reaches the preset nitrogen oxide threshold, the three-way solenoid valve is activated for sampling and the urea pump is turned on;

[0012] After the three-way solenoid valve samples for the preset time, it stops and shuts off the urea pump synchronously, and marks the urea sampling as full bottle state;

[0013] A sampling signal is generated based on the full bottle status to send the urea in the sampling bottle for inspection to determine whether the low-quality urea is qualified.

[0014] Optionally, when the urea quality value reaches the urea quality alarm threshold, an alarm signal is generated and forwarded to the cloud platform server, and the urea consumption value is uploaded synchronously, which also includes:

[0015] The cloud platform obtains the urea consumption value;

[0016] Calculate the ratio of the accumulated urea consumption value within the set time to the fuel consumption value to obtain the urea-fuel ratio data of the set period;

[0017] Based on the difference between the urine-fuel ratio of two consecutive cycles and the difference between the historical average urine-fuel ratio and the urine-fuel ratio of the current cycle, the abnormal urea consumption and urea quality are obtained and fed back to the ECU;

[0018] If the difference between the urine-fuel ratio of the current cycle and the urine-fuel ratio of the previous cycle is greater than a first threshold percentage, a urea consumption abnormality signal is generated, and if the difference between the urine-fuel ratio of the current cycle and the historical average urine-fuel ratio is greater than a second threshold percentage, a urea quality abnormality signal is generated;

[0019] The abnormal urea consumption signal and the abnormal urea quality signal are sent to the ECU for cyclically obtaining the urea quality value and the urea consumption value.

[0020] Optionally, the calculation expression of the urine-fuel ratio of the current cycle is:

[0021] R1=(U1-U0) / (F1-F0)

[0022] Where r1 is the urea-fuel ratio in the current cycle, f1 is the cumulative fuel consumption in the current cycle, f0 is the cumulative fuel consumption in the previous cycle, u1 is the current cumulative urea consumption, and u1 is the cumulative urea consumption in the previous cycle.

[0023] Optionally, opening the urea injection valve based on the alarm signal further includes determining a state of the urea injection valve, and if the state of the urea injection valve itself is an open state, maintaining the valve open;

[0024] If the urea injection valve is in the closed state, the urea injection valve is opened based on the alarm signal.

[0025] Optionally, generating a sampling signal based on the full bottle status also includes uploading the full bottle status to a cloud platform;

[0026] After the cloud platform receives the full bottle status, it marks the associated vehicle to temporarily suspend sampling until it receives a change in the sampling bottle status, at which point it resumes sampling.

[0027] Optionally, marking the urea sampling as a full bottle state further includes using binary to mark the urea sampling state, wherein the full bottle state is "1" and the empty bottle state is "0".

[0028] In a second aspect, the present invention provides a urea detection system for a post-treatment system, comprising:

[0029] Engine ECU, sensor group, urea injection valve, sampling bottle, urea pump, three-way solenoid valve and SCR system;

[0030] The sensor group is used to collect urea mass value and nitrogen oxide concentration value respectively;

[0031] The urea injection valve is connected to the SCR system and is connected to the urea tank through a three-way solenoid valve and a urea pump, and is used to switch between the SCR system and the urea tank;

[0032] The sampling bottle is connected to the urea tank via a three-way solenoid valve and a urea pump and is used for sampling when the urea quality is abnormal;

[0033] The SCR system is used to generate urea consumption

[0034] The engine ECU is electrically connected to the sensor group, the urea injection valve, the urea pump, the three-way solenoid valve and the SCR system respectively to execute the steps of the above method.

[0035] Optionally, the sensor group includes a urea quality sensor and a nitrogen oxide sensor; wherein the urea quality sensor is installed on the urea tank and is used to directly detect the quality of urea in the urea tank;

[0036] The nitrogen oxide sensor is installed at the outlet of the SCR system to obtain the nitrogen oxide concentration value.

[0037] In a third aspect, the present invention provides a urea detection device for a post-treatment system, comprising a data acquisition module, an alarm and upload module, a nitrogen oxide detection module, and a sampling module.

[0038] The data acquisition module is used to obtain urea mass value and urea consumption value;

[0039] The alarm and upload module is used to generate an alarm signal and forward it to the cloud platform server when the urea quality value reaches the urea quality alarm threshold, and to synchronously and continuously upload the urea consumption value;

[0040] The nitrogen oxide detection module is used to open the urea injection valve based on the alarm signal; when the urea injection valve is opened, the nitrogen oxide concentration value is obtained; if the nitrogen oxide concentration value reaches the preset nitrogen oxide threshold, the three-way solenoid valve is activated for sampling and the urea pump is turned on;

[0041] The sampling module is used to stop and synchronously close the urea pump after the three-way solenoid valve samples for a preset time, and mark the urea sampling as a full bottle state; based on the full bottle state, a sampling signal is generated to send the urea in the sampling bottle for inspection to obtain a low-quality urea evaluation result.

[0042] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0043] After the post-treatment system issues an early warning, the urea quality value and urea consumption value are collected for comprehensive judgment, and the data is uploaded to the cloud platform for further continuous calculation and monitoring of urea consumption and urea quality. The urea sampling start is automatically controlled to achieve high-precision detection of urea quality and urea consumption at the same time.

[0044] The system has a streamlined structure and uses the engine ECU to sense urea mass and consumption in real time, achieving automatic control of the urea injection valve, sampling bottle, urea pump, and three-way solenoid valve. This ultimately enables automatic sampling and testing of the post-treatment system, and generates early warning information in real time to avoid the risk of product emissions exceeding standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a flow chart of a urea detection method applied to a post-processing system according to the present invention;

[0046] Figure 2 This is a diagram illustrating an embodiment of cloud platform data processing according to the present invention;

[0047] Figure 3 This is a structural block diagram of a detection device applied to a post-processing system according to the present invention.

[0048] Reference numerals: 1. urea tank, 2. urea quality sensor, 3. urea pump, 4. ECU, 5. three-way solenoid valve, 6. sampling bottle, 7. urea injection valve, 8. SCR system, 9. nitrogen oxide sensor, 10. urea pipe. DETAILED DESCRIPTION

[0049] In order to more fully understand the technical content of the present invention, the technical solution of the present invention is further introduced and illustrated in conjunction with specific embodiments below, but is not limited thereto.

[0050] Example 1

[0051] This embodiment provides a urea detection method for a post-processing system. Figure 1 Shown include:

[0052] Step 1: Obtaining urea mass value and urea consumption value;

[0053] Step 2: When the urea quality value reaches the urea quality alarm threshold, an alarm signal is generated and forwarded to the cloud platform server, and the urea consumption value is synchronously and continuously uploaded;

[0054] Step 3: Based on the alarm signal, open the urea injection valve;

[0055] Step 4: After the urea injection valve is opened, obtain the nitrogen oxide concentration value;

[0056] Step 5: If the nitrogen oxide concentration reaches the preset nitrogen oxide threshold, the three-way solenoid valve is started for sampling and the urea pump is turned on;

[0057] Step 6: After the three-way solenoid valve samples for a preset time, the urea pump is stopped and closed synchronously, and the urea sample is marked as full;

[0058] Step 7: Generate a sampling signal based on the full bottle state, which is used to send the urea in the sampling bottle for inspection to determine whether the low-quality urea is qualified.

[0059] Optionally, when the urea quality value reaches the urea quality alarm threshold, an alarm signal is generated and forwarded to the cloud platform server, and the urea consumption value is uploaded synchronously, such as Figure 2 Also shown are:

[0060] The cloud platform obtains the urea consumption value;

[0061] Calculate the ratio of the accumulated urea consumption value within the set time to the fuel consumption value to obtain the urea-fuel ratio data of the set period;

[0062] Based on the difference between the urine-fuel ratio of two consecutive cycles and the difference between the historical average urine-fuel ratio and the urine-fuel ratio of the current cycle, the abnormal urea consumption and urea quality are obtained and fed back to the ECU;

[0063] If the difference between the current period urea fuel ratio and the last period urea fuel ratio is greater than the first threshold percentage, a urea consumption abnormality signal is generated, and the difference between the current period urea fuel ratio and the historical average urea fuel ratio is greater than the second threshold percentage, a urea quality abnormality signal is generated;

[0064] The urea consumption abnormality signal and the urea quality abnormality signal are sent to the ECU for cyclically obtaining the urea quality value and the urea consumption value.

[0065] Optionally, the calculation expression of the current period urea fuel ratio is:

[0066] r1= (u1-u0) / (f1-f0)

[0067] In the formula, r1 is the urea fuel ratio in the current period, f1 is the cumulative fuel consumption in the current period, f0 is the cumulative fuel consumption in the last period, u1 is the cumulative urea consumption in the current period, and u1 is the cumulative urea consumption in the last period.

[0068] In this embodiment, the urea consumption (u1-u0) in the period, the period fuel consumption (f1-f0), and the urea fuel ratio r1 in the period are calculated every interval T hours, and the next period urea fuel ratio r2 is calculated in the same way, r2= (u2-u1) / (f2-f1). The total urea fuel ratio data is Rt=Ut / Ft. The total urea consumption and the total fuel consumption. If the difference between the current period urea fuel ratio and the last period urea fuel ratio is greater than a%, it is considered that the urea consumption is abnormal, and at this time, the historical urea fuel ratio is compared, and if the difference is greater than b%, a urea quality abnormality signal is output to the ECU.

[0069] Optionally, based on the alarm signal, the urea injection valve is opened, and the state of the urea injection valve is judged. If the state of the urea injection valve is in the open state, the open state is maintained.

[0070] If the urea injection valve is in the closed state, the urea injection valve is opened based on the alarm signal.

[0071] Optionally, the sampling signal is generated based on the full bottle state, and the full bottle state is uploaded to the cloud platform.

[0072] After the cloud platform receives the full bottle state, the associated vehicle is temporarily marked to stop sampling, and the sampling state is restored until the sampling bottle state changes.

[0073] Optionally, the urea sampling is marked as a full bottle state, and a binary is used to mark the urea sampling state, wherein the full bottle state is "1" and the empty bottle state is "0".

[0074] Embodiment 2

[0075] This embodiment provides a urea detection system 8 applied to a post-processing system 8, such as Figure 3 Shown include:

[0076] Engine ECU 4, sensor group, urea injection valve 7, sampling bottle 6, urea pump 3, three-way solenoid valve 5 and SCR system 8;

[0077] The sensor group is used to collect urea mass value and nitrogen oxide concentration value respectively;

[0078] The urea injection valve 7 is connected to the SCR system 8 and is connected to the urea tank 1 through the three-way solenoid valve 5 and the urea pump 3, and is used to switch between the SCR system 8 and the urea tank 1;

[0079] The sampling bottle 6 is connected to the urea tank 1 through the three-way solenoid valve 5 and the urea pump 3, and is used for sampling when the urea quality is abnormal;

[0080] The SCR system 8 is used to generate urea consumption

[0081] The engine ECU 4 is electrically connected to the sensor group, the urea injection valve 7 , the urea pump 3 , the three-way solenoid valve 5 and the SCR system 8 to execute the steps of the above method.

[0082] Optionally, the sensor group includes a urea quality sensor 2 and a nitrogen oxide sensor 9; wherein the urea quality sensor 2 is installed on the urea tank 1 and is used to directly detect the quality of urea in the urea tank 1;

[0083] The nitrogen oxide sensor 9 is installed at the outlet of the SCR system 8 to obtain the nitrogen oxide concentration value.

[0084] In this embodiment, the urea tank 1 is connected to other accessories via a urea pipe 10, supplying urea to the sampling bottle 6 and SCR system 8. The ECU 4 records the status of the sampling bottle 6 and uploads it to the cloud platform. If the bottle is full, sampling is impossible. Service personnel can count the vehicle numbers based on the status of the sampling bottle 6 and determine the next vehicle number for sampling, eliminating manual troubleshooting and reducing maintenance costs.

[0085] Example 3

[0086] This embodiment provides a urea detection device applied to a post-treatment system, including a data acquisition module, an alarm and upload module, a nitrogen oxide detection module, and a sampling module.

[0087] The data acquisition module is used to obtain urea mass value and urea consumption value;

[0088] The alarm and upload module is used to generate an alarm signal and forward it to the cloud platform server when the urea quality value reaches the urea quality alarm threshold, and to synchronously and continuously upload the urea consumption value;

[0089] The nitrogen oxide detection module is used to open the urea injection valve based on the alarm signal; when the urea injection valve is opened, the nitrogen oxide concentration value is obtained; if the nitrogen oxide concentration value reaches the preset nitrogen oxide threshold, the three-way solenoid valve is activated for sampling and the urea pump is turned on;

[0090] The sampling module is used to stop and synchronously close the urea pump after the three-way solenoid valve samples for a preset time, and mark the urea sampling as a full bottle state; based on the full bottle state, a sampling signal is generated to send the urea in the sampling bottle for inspection to obtain a low-quality urea evaluation result.

[0091] In summary, after the post-treatment system issues an early warning, the present invention collects urea quality values ​​and urea consumption values ​​for comprehensive judgment, uploads the data to the cloud platform, further calculates the urea consumption, and controls the start of urea sampling at the same time, thereby achieving high-precision detection of urea quality and urea consumption at the same time.

[0092] The system has a streamlined structure and uses the engine ECU to sense urea mass and consumption in real time, achieving automatic control of the urea injection valve, sampling bottle, urea pump, and three-way solenoid valve. This ultimately enables automatic sampling and testing of the post-treatment system, and generates early warning information in real time to avoid the risk of product emissions exceeding standards.

[0093] The embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0094] The embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0095] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0096] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0097] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0098] The above is only a preferred embodiment of the present invention. Without departing from the technical principles of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be considered as the scope of protection of the present invention.

Claims

1. A urea detection method applied to a post-treatment system, characterized in that: include: Obtain urea mass value and urea consumption value; When the urea quality value reaches the urea quality alarm threshold, an alarm signal is generated and forwarded to the cloud platform server, and the urea consumption value is synchronously and continuously uploaded; Based on the alarm signal, the urea injection valve is opened; When the urea injection valve is opened, the nitrogen oxide concentration value is obtained; If the nitrogen oxide concentration reaches the preset nitrogen oxide threshold, the three-way solenoid valve is activated for sampling and the urea pump is turned on; After the three-way solenoid valve samples for the preset time, it stops and shuts off the urea pump synchronously, and marks the urea sampling as full bottle state; Generate a sampling signal based on the full bottle status to send the urea in the sampling bottle for inspection to determine whether the low-quality urea is qualified; When the urea quality value reaches the urea quality alarm threshold, an alarm signal is generated and forwarded to the cloud platform server, and the urea consumption value is uploaded synchronously, including: The cloud platform obtains the urea consumption value; Calculate the ratio of the accumulated urea consumption value within the set time to the fuel consumption value to obtain the urea-fuel ratio data of the set period; According to the difference between the urine-fuel ratio of two consecutive cycles and the difference between the historical average urine-fuel ratio and the urine-fuel ratio of the current cycle, the abnormal urea consumption and the abnormal urea quality are obtained and fed back to the ECU.

2. The urea detection method for a post-processing system according to claim 1, wherein: Obtain abnormal urea consumption and urea quality, including: If the difference between the urine-fuel ratio of the current cycle and the urine-fuel ratio of the previous cycle is greater than a first threshold percentage, a urea consumption abnormality signal is generated, and if the difference between the urine-fuel ratio of the current cycle and the historical average urine-fuel ratio is greater than a second threshold percentage, a urea quality abnormality signal is generated; The abnormal urea consumption signal and the abnormal urea quality signal are sent to the ECU for cyclically obtaining the urea quality value and the urea consumption value.

3. The urea detection method applied to the post-processing system according to claim 2, characterized in that: The calculation expression of the urine-fuel ratio in the current cycle is: ； Where, is the urine-to-fuel ratio in the current cycle, is the accumulated fuel consumption in the current cycle, is the accumulated fuel consumption in the previous cycle, is the current accumulated urea consumption, The accumulated urea consumption in the previous cycle.

4. The urea detection method for a post-processing system according to claim 1, wherein: Based on the alarm signal, the urea injection valve is opened, and the state of the urea injection valve is judged. If the state of the urea injection valve itself is open, the valve is kept open; If the urea injection valve is in the closed state, the urea injection valve is opened based on the alarm signal.

5. The urea detection method for a post-processing system according to claim 1, wherein: generating a sampling signal based on a full bottle status, and uploading the full bottle status to a cloud platform; After the cloud platform receives the full bottle status, it marks the associated vehicle to temporarily suspend sampling until it receives a change in the sampling bottle status, at which point it resumes sampling.

6. The urea detection method for a post-processing system according to claim 1, wherein: Marking the urea sampling as a full bottle state also includes using binary to mark the urea sampling state, wherein the full bottle state is "1" and the empty bottle state is "0".

7. A urea detection system for a post-processing system, characterized in that: include: Engine ECU, sensor group, urea injection valve, sampling bottle, urea pump, three-way solenoid valve and SCR system; The sensor group is used to collect urea mass value and nitrogen oxide concentration value respectively; The urea injection valve is connected to the SCR system and is connected to the urea tank through a three-way solenoid valve and a urea pump, and is used to switch between the SCR system and the urea tank; The sampling bottle is connected to the urea tank via a three-way solenoid valve and a urea pump and is used for sampling when the urea quality is abnormal; The SCR system is used to generate urea consumption; The engine ECU is electrically connected to the sensor group, the urea injection valve, the urea pump, the three-way solenoid valve and the SCR system respectively to perform the steps of the urea detection method according to any one of claims 1 to 6.

8. The urea detection system for a post-processing system according to claim 7, characterized in that: The sensor group includes a urea quality sensor and a nitrogen oxide sensor; wherein the urea quality sensor is installed on the urea tank and is used to directly detect the quality of urea in the urea tank; The nitrogen oxide sensor is installed at the outlet of the SCR system to obtain the nitrogen oxide concentration value.

9. A urea detection device for a post-treatment system, characterized in that: The method for performing the urea detection method according to any one of claims 1 to 6 comprises: a data acquisition module, an alarm and upload module, a nitrogen oxide detection module, and a sampling module; The data acquisition module is used to obtain urea mass value and urea consumption value; The alarm and upload module is used to generate an alarm signal and forward it to the cloud platform server when the urea quality value reaches the urea quality alarm threshold, and to synchronously and continuously upload the urea consumption value; The nitrogen oxide detection module is used to open the urea injection valve based on the alarm signal; when the urea injection valve is opened, the nitrogen oxide concentration value is obtained; if the nitrogen oxide concentration value reaches the preset nitrogen oxide threshold, the three-way solenoid valve is activated for sampling and the urea pump is turned on; The sampling module is used to stop and synchronously close the urea pump after the three-way solenoid valve samples for a preset time, and mark the urea sampling as a full bottle state; based on the full bottle state, a sampling signal is generated to send the urea in the sampling bottle for inspection to obtain a low-quality urea evaluation result.

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