CN114592946B - A Post-treatment Desulfurization System and Its Control Strategy - Google Patents

Abstract

The invention relates to the technical field of engine exhaust gas treatment, and discloses a post-treatment desulfurization system and its control strategy. The post-treatment desulfurization system includes an engine, a turbine, and a sulfur trap. The air inlet is connected, and the exhaust port of the sulfur trap is connected with the air inlet of the turbine. The control strategy of the post-treatment sulfur removal system includes comparing the obtained operating parameter information of the sulfur trap with a corresponding threshold; when the operating parameter information is greater than or equal to the corresponding threshold, it is indicated that the sulfur trap needs to be updated. The post-treatment desulfurization system and its control strategy improve the problem that the SCR catalyst is prone to hydrothermal aging caused by the existing SCR desulfurization method.

Description

A Post-treatment Desulfurization System and Its Control Strategy

technical field

The invention relates to the technical field of engine exhaust gas treatment, in particular to an aftertreatment desulfurization system and a control strategy thereof.

Background technique

In the aftertreatment system of the engine, the SCR (Selective Catalytic Reduction, selective catalytic reduction technology) system mainly uses copper molecular sieve catalysts, and the NOx conversion efficiency is relatively high. However, the fuel used by existing diesel engines contains a certain amount of sulfur, and the exhaust gas discharged after the engine turbine contains sulfur compounds. At the same time, the lubricant also contains sulfur. Therefore, there is a risk of sulfur poisoning in the SCR, and the SCR needs to be regularly desulfurized.

In the prior art, a DOC (Oxidation Catalytic Converter) is arranged before the SCR, and the HC (fuel oil) that is not fully burned is injected into the cylinder, and enters the post-treatment with the exhaust gas, and the unburned fuel is under the action of the DOC catalyst. Oxidation releases heat and increases the post-treatment temperature to achieve high-temperature desulfurization in the DOC; another way is to inject fuel into the exhaust pipe before the DOC, and the fuel is oxidized and released under the action of the DOC catalyst to increase the after-treatment temperature. Thereby realizing high temperature desulfurization in DOC. The disadvantages of the above two methods are that it is easy to cause hydrothermal aging of the SCR catalyst and deteriorate the fuel economy.

Contents of the invention

The invention provides a post-treatment desulfurization system and its control strategy, which can improve the problem that the SCR catalyst is prone to hydrothermal aging caused by the existing SCR desulfurization method.

To achieve the above object, the present invention provides the following technical solutions:

A post-treatment desulfurization system, comprising: an engine, a turbine and a sulfur trap, the exhaust port of the engine communicates with the intake port of the sulfur trap, the exhaust port of the sulfur trap communicates with the The air inlet of the turbine communicates.

The post-treatment desulfurization system provided by the present invention arranges a trap between the exhaust port of the engine and the turbine, the exhaust port of the engine communicates with the intake port of the sulfur trap, and the exhaust port of the sulfur trap communicates with the turbine The intake port of the exhaust port is connected so that the exhaust gas can pass through the trap. The high-efficiency temperature window of the sulfur trap is 250°C to 550°C. The sulfur trap is arranged in front of the turbine to capture SOx (sulfur oxide) in the exhaust gas by using high-temperature exhaust gas, without high-temperature desulfurization, which can reduce Deal with the risk of system SCR sulfur poisoning and improve fuel economy without causing hydrothermal aging of the SCR catalyst.

Optionally, the sulfur trap has a plurality of parallel channels, the air inlet of each channel is connected with the exhaust port of the engine, and the exhaust port of each channel is connected with the exhaust port of the turbine. The gas inlets are connected, and the walls of each channel are coated with a sulfur trapping layer.

Optionally, the sulfur trapping layer includes a carrier layer and a sulfur trapping agent.

Optionally, the sulfur collector includes alkali metal oxides and/or alkaline earth metal oxides.

Optionally, the sulfur trap is detachably connected to the exhaust port of the engine and the intake port of the turbine.

The present invention also provides a control strategy for a post-treatment desulfurization system, which is applied to any one of the post-treatment desulfurization systems provided in the above technical solutions. The control strategy includes:

Comparing the obtained operating parameter information of the sulfur trap with corresponding threshold values;

When the operating parameter information is greater than or equal to the corresponding threshold, it indicates that the sulfur trap needs to be updated;

Wherein, the post-treatment desulfurization system includes:

An engine, a turbine and a sulfur trap, the exhaust port of the engine communicates with the intake port of the sulfur trap, and the exhaust port of the sulfur trap communicates with the intake port of the turbine.

The control strategy of the post-treatment sulfur removal system provided by the present invention compares the obtained operating parameter information of the sulfur trap with the corresponding threshold, and can indicate that the sulfur trap needs to be updated when the operating parameter information is greater than or equal to the corresponding threshold , thus helping to ensure the efficiency of the sulfur trap.

At the same time, a sulfur trap is arranged between the exhaust port of the engine and the turbine, and the exhaust port of the engine communicates with the intake port of the sulfur trap, and the exhaust port of the sulfur trap communicates with the intake port of the turbine , so that the exhaust gas can pass through the sulfur trap. The high-efficiency temperature window of the sulfur trap is between 250°C and 550°C. High-temperature desulfurization can reduce the risk of SCR sulfur poisoning in the aftertreatment system and improve fuel economy without causing hydrothermal aging of the SCR catalyst.

Optionally, the comparing the acquired operating parameter information of the sulfur trap with the corresponding threshold includes at least one of the following ways:

Obtaining a sulfur escape concentration, and comparing the sulfur escape concentration with a sulfur concentration threshold;

Obtaining the total amount of sulfur captured since the sulfur trap was used, and comparing the total amount of sulfur captured with a threshold value of sulfur capture;

The total mileage since the sulfur trap is used is acquired, and the total mileage is compared with a mileage threshold.

Optionally, when comparing the obtained operating parameter information of the sulfur trap with the corresponding threshold value, including obtaining the total amount of sulfur captured by the sulfur trap since it is used, the total amount of sulfur captured When compared with the sulfur capture threshold, the control strategy specifically includes:

calculating the real-time sulfur capture mass of the sulfur trap;

Accumulating the real-time sulfur capture mass with the sulfur capture mass of each historical driving cycle since the sulfur trap is used, to obtain the total sulfur capture amount;

The total amount of captured sulfur is compared with the threshold value of the captured amount of sulfur, and when the total amount of captured sulfur is greater than or equal to the threshold value of the captured amount of sulfur, it is indicated that the sulfur trap needs to be updated.

Optionally, the calculating the real-time sulfur capture quality of the sulfur trap specifically includes:

Integrating the sulfur mass flow in the exhaust gas in the current driving cycle to obtain the integral value of the sulfur mass flow in the current driving cycle;

The real-time sulfur capture quality is obtained by multiplying the integral value by the conversion efficiency of the sulfur trap.

Optionally, before integrating the sulfur mass flow in the exhaust gas in the current driving cycle to obtain the integral value of the sulfur mass flow in the current driving cycle, it includes:

The initial value of the sulfur mass flow rate in the exhaust gas is obtained through the engine speed, the fuel injection quantity and the sulfur concentration in the fuel;

The sulfur mass flow in the exhaust gas is obtained by correcting the initial value of the sulfur mass flow.

Optionally, the way of correcting the initial value of the sulfur mass flow rate includes at least one of the following ways:

The initial value of the sulfur mass flow rate is corrected by the air excess influence coefficient;

The initial value of the sulfur mass flow rate is corrected by the ambient temperature influence coefficient;

The initial value of the sulfur mass flow rate is corrected by the environmental pressure influence coefficient.

Optionally, the accumulating the real-time sulfur capture quality and the sulfur capture quality of each historical driving cycle since the use of the sulfur trap specifically includes:

Obtain the sulfur capture mass of each historical driving cycle or the sum of the sulfur capture mass of each historical driving cycle;

Accumulate the real-time sulfur trapping mass and the corresponding sulfur trapping mass of each historical driving cycle or the sum of the sulfur trapping mass of each historical driving cycle.

Optionally, after the end of the current driving cycle, the real-time sulfur capture quality is stored, so as to calculate the total amount of sulfur captured by the sulfur trap in the next driving cycle.

Optionally, when comparing the obtained operating parameter information of the sulfur trap with the corresponding threshold value, it includes obtaining the total mileage since the sulfur trap is used, and comparing the total mileage with the mileage threshold When compared, the control strategies include:

Accumulate the real-time mileage of the current driving cycle and the mileage of each historical driving cycle since the use of the sulfur trap to obtain the total mileage;

The total mileage is compared with a mileage threshold, and when the total mileage is greater than or equal to the mileage threshold, it is indicated that the sulfur trap needs to be updated.

Description of drawings

Fig. 1 is a structural schematic diagram of a sulfur trap in a post-treatment desulfurization system provided by an embodiment of the present invention (the hollow arrow above indicates the flow direction of the exhaust gas flow);

Fig. 2 is a schematic flow chart of a control strategy of a post-treatment desulfurization system provided by an embodiment of the present invention;

3 is a schematic flow diagram of some links in the control strategy of a post-treatment desulfurization system provided by an embodiment of the present invention;

Fig. 4 is a schematic flow diagram of some links in the control strategy of a post-treatment desulfurization system provided by an embodiment of the present invention;

Fig. 5 is a schematic flow diagram of some links in the control strategy of a post-treatment desulfurization system provided by an embodiment of the present invention;

Fig. 6 is a logic diagram of a control strategy of a post-treatment desulfurization system provided by an embodiment of the present invention;

Fig. 7 is a schematic flowchart of a control strategy of a post-treatment desulfurization system provided by an embodiment of the present invention;

Fig. 8 is a schematic structural diagram of an engine system provided with an aftertreatment desulfurization system provided by an embodiment of the present invention.

Icons: 1-sulfur trapping layer; 11-carrier layer; 12-sulfur trapping agent; 2-base layer; 3-filter; 4-compressor; 5-intake throttle valve; 6-engine; 7 8-DOC; 9-DPF; 10-SCR; 13-ASC; 14-catalyst; 100-sulfur trap.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Figure 8, a post-treatment desulfurization system provided in this embodiment includes an engine 6, a turbine 7 and a sulfur trap 100, wherein the exhaust port of the engine 6 communicates with the intake port of the sulfur trap 100 , the exhaust port of the sulfur trap 100 communicates with the intake port of the turbine 7 .

In the post-treatment desulfurization system provided in this embodiment, a trap is arranged between the exhaust port of the engine and the turbine, the exhaust port of the engine communicates with the intake port of the sulfur trap, and the exhaust port of the sulfur trap communicates with the intake port of the sulfur trap. The intake port of the turbine communicates so that the exhaust gases can pass through the trap. The high-efficiency temperature window of the sulfur trap 100 is between 250°C and 550°C. The sulfur trap 100 is arranged in front of the turbine to capture SOx (sulfur oxides) in the exhaust gas by using high-temperature exhaust gas, without the need for high-temperature desulfurization. Reduce the risk of SCR sulfur poisoning in the aftertreatment system and improve fuel economy without causing hydrothermal aging of the SCR catalyst.

When the above-mentioned sulfur trap is specifically set, in an optional implementation mode, the sulfur trap has a plurality of parallel channels, the air inlets of each channel are connected with the exhaust port of the engine, and the exhaust ports of each channel All communicate with the air inlet of the turbine, and the wall surface of each channel is coated with a sulfur trapping layer 1 .

When specifically setting the above-mentioned sulfur trapping layer 1 , as shown in FIG. 1 , in an optional implementation manner, the sulfur trapping layer includes a carrier layer 11 and a sulfur trapping agent 12 .

In an optional implementation, the sulfur trapping agent 12 includes alkali metal oxides and/or alkaline earth metal oxides, for example: the sulfur trapping agent 12 may include potassium oxides, barium oxides, and cerium oxides at least one of the three.

The sulfur trapping layer 1 includes a carrier layer 11 and a sulfur trapping agent 12. In an optional implementation, the carrier layer 11 is disposed on the wall of the channel, and the sulfur trapping agent 12 layer is disposed on the carrier layer 11. Exemplarily, the carrier layer 11 can be coated on the wall surface of the channel, and the sulfur collector 12 layer can be coated on the carrier layer 11 .

In another optional implementation manner, the sulfur trapping agent 12 is mixed in the carrier layer 11 and coated on the wall surface of the channel together with the carrier layer 11 .

Specifically, when the above-mentioned carrier layer 11 is provided, the carrier layer 11 may include an aluminum oxide layer.

In an optional implementation manner, the sulfur trap includes a base layer 2 (for example: a cordierite layer), and the carrier layer 11 is coated on the base layer 2 .

In order to improve the trapping efficiency of the sulfur trap 100 , in an optional implementation manner, a catalyst 14 is provided on the sulfur trap layer 1 . Illustratively, catalyst 14 includes platinum (Pt).

In an optional implementation manner, the sulfur trap is detachably connected to the exhaust port of the engine and the intake port of the turbine. For example: the sulfur trap is connected to the exhaust port of the engine through a flange, and the sulfur trap is also connected to the turbine inlet through a flange.

The sulfur trap is detachably connected to the exhaust port of the engine and the intake port of the turbine. When the sulfur trap needs to be updated, a new sulfur trap can be directly replaced, and the operation is more convenient.

In this embodiment, a sulfur trapping agent 12 is arranged in each channel of the sulfur trap, with alkali metal oxide and/or alkaline earth metal oxide as the SOx trapping agent, and aluminum oxide as the carrier layer 11. The SOx in the system is captured to play the role of sulfur capture. At the same time, the sulfur trap 100 is equivalent to a "filter element", which has a low cost and can be replaced regularly, which can reduce the risk of sulfur poisoning of the after-treatment SCR. Renewing the sulfur trap 100 through the control strategy of the post-treatment desulfurization system mentioned below is also conducive to improving the reliability of the SCR catalyst in the post-treatment system and improving fuel economy.

When the engine system adopts the post-treatment desulfurization system provided in this embodiment, the SOx in the exhaust gas is captured by reacting with the sulfur trapping agent 12 to generate sulfate, but the generated sulfate is difficult to desulfurize through high temperature. Therefore, the sulfur capture The trap 100 needs to be renewed after being used for a period of time, so as to avoid sulfur escape due to the decrease of the adsorption capacity of the sulfur trap 100, which will adversely affect the downstream SCR. Therefore, the control, update and maintenance of the sulfur trap 100 are also particularly important.

As shown in Figure 2, a control strategy for a post-treatment desulfurization system provided in this embodiment is applied to any post-treatment desulfurization system provided in the above technical solution, and the control strategy includes:

Step S1, comparing the acquired operating parameter information of the sulfur trap 100 with the corresponding threshold;

When the operating parameter information is greater than or equal to the corresponding threshold, it indicates that the sulfur trap 100 needs to be updated.

The control strategy of the post-processing sulfur removal system provided in this embodiment compares the obtained operating parameter information of the sulfur trap 100 with the corresponding threshold, and can indicate that the sulfur trap needs to be updated when the operating parameter information is greater than or equal to the corresponding threshold. The trap 100 is beneficial to ensure the efficiency of the sulfur trap.

At the same time, a sulfur trap is arranged between the exhaust port of the engine and the turbine, and the exhaust port of the engine communicates with the intake port of the sulfur trap, and the exhaust port of the sulfur trap communicates with the intake port of the turbine , so that the exhaust gas can pass through the sulfur trap. The high-efficiency temperature window of the sulfur trap 100 is between 250°C and 550°C. The sulfur trap 100 is arranged in front of the turbine to capture SOx in the exhaust gas , without high-temperature desulfurization, which can reduce the risk of SCR sulfur poisoning in the aftertreatment system and improve fuel economy without causing hydrothermal aging of the SCR catalyst.

When the operating parameter information is greater than or equal to the corresponding threshold, it indicates that the sulfur trap 100 needs to be updated. For example, when the sulfur trap is detachably connected to the exhaust port of the engine and the intake port of the turbine, The existing sulfur trap 100 can be removed and replaced with a new sulfur trap 100 .

In an optional implementation manner, step S1, comparing the obtained operating parameter information of the sulfur trap 100 with the corresponding threshold value, includes at least one of the following methods (that is, may include one of the following methods species, two or three):

Method 1: Obtain the sulfur escape concentration, and compare the sulfur escape concentration with the sulfur concentration threshold;

Method 2: Obtain the total amount of sulfur captured since the sulfur trap 100 is used, and compare the total amount of sulfur captured with the threshold value of the sulfur capture amount;

Way 3: Obtain the total mileage since the use of the sulfur trap 100, and compare the total mileage with the mileage threshold.

Exemplarily, an SO ₂ concentration sensor may be arranged downstream of the sulfur trap 100 to detect the sulfur slip concentration through the SO ₂ concentration sensor.

At the same time, an SO ₂ concentration sensor can also be arranged upstream of the sulfur trap 100 to accurately determine the sulfur concentration in the fuel and make the sulfur accumulation calculation more accurate.

It should be noted that when step S1 compares the obtained operating parameter information of the sulfur trap 100 with the corresponding threshold, including two or three of the above-mentioned methods, one of the methods corresponds to the sulfur trap 100 When the operating parameter information of 100 is greater than or equal to the corresponding threshold, it indicates that the sulfur trap 100 needs to be updated.

In step S1, comparing the obtained operating parameter information of the sulfur trap 100 with the corresponding threshold value, including obtaining the total amount of sulfur captured since the sulfur trap 100 was used, and comparing the total amount of sulfur captured with the amount of sulfur captured When comparing thresholds, as shown in Figure 3, in an optional implementation, the control strategy specifically includes:

Step S11, calculating the real-time sulfur capture quality of the sulfur trap 100;

Step S12, adding up the real-time sulfur capture mass and the sulfur capture mass of each historical driving cycle since the use of the sulfur trap 100 to obtain the total amount of sulfur capture;

Step S13 , comparing the total amount of captured sulfur with the threshold value of sulfur capture amount, and when the total amount of sulfur capture is greater than or equal to the threshold value of sulfur capture amount, it is indicated that the sulfur trap 100 needs to be updated.

As shown in Figure 4, in an optional implementation, step S11, calculating the real-time sulfur capture quality of the sulfur trap 100, specifically includes:

Step S21, integrating the mass flow rate of sulfur in the exhaust gas in the current driving cycle to obtain the integral value of the mass flow rate of sulfur in the current driving cycle;

Step S22 , multiplying the integral value by the conversion efficiency of the sulfur trap 100 to obtain the real-time sulfur trap quality.

In this way, after updating the sulfur trap 100, it is necessary to reset the integral value calculated in the ECU (Electronic Control Unit, electronic control unit), the total amount of sulfur captured since the sulfur trap 100 was used, etc. to 0 .

As shown in Figure 5, in an optional implementation, before step S21, integrating the sulfur mass flow in the exhaust gas in the current driving cycle to obtain the integral value of the sulfur mass flow in the current driving cycle, includes:

Step S31, obtain the initial value of sulfur mass flow rate in exhaust gas according to engine speed, fuel injection quantity and sulfur concentration in fuel;

Step S32, correcting the initial value of the sulfur mass flow rate to obtain the sulfur mass flow rate in the exhaust gas.

In an optional implementation manner, step S32, the manner of correcting the initial value of the sulfur mass flow rate includes at least one of the following manners:

Method 1. Correct the initial value of the sulfur mass flow rate through the influence coefficient of excess air;

Method 2: Correct the initial value of the sulfur mass flow rate through the influence coefficient of the ambient temperature;

Method 3: The initial value of the sulfur mass flow rate is corrected by the environmental pressure influence coefficient.

In an optional implementation, step S12 is to accumulate the real-time sulfur capture quality and the sulfur capture quality of each historical driving cycle since the use of the sulfur trap 100, specifically including:

Obtain the sulfur capture mass of each historical driving cycle or the sum of the sulfur capture mass of each historical driving cycle;

Accumulate the real-time sulfur capture mass with the corresponding sulfur capture mass of each historical driving cycle or the sum of the sulfur capture mass of each historical driving cycle, that is, when the sulfur capture mass of each historical driving cycle is obtained, Accumulate the real-time sulfur capture mass and the sulfur capture mass of each historical driving cycle; when the obtained sulfur capture mass is the sum of each historical driving cycle, the real-time sulfur The sum of the set masses is accumulated.

In an optional implementation manner, after the current driving cycle ends, the real-time sulfur capture quality is stored, so as to calculate the total amount of sulfur captured by the sulfur trap 100 in the next driving cycle.

Exemplarily, after the end of the current driving cycle, when the ECU is powered off (that is, when T15 is powered off), the real-time sulfur capture quality is updated to the memory; after a new driving cycle starts, that is, after the ECU is powered on (that is, when T15 is powered on) The corresponding sulfur trapping mass of each historical driving cycle or the sum of the sulfur trapping mass of each historical driving cycle is read from the memory.

When step S1 compares the obtained operating parameter information of the sulfur trap 100 with the corresponding threshold value, including obtaining the total mileage since the use of the sulfur trap 100, and comparing the total mileage with the mileage threshold, a In an optional implementation, the control strategy includes:

Accumulate the real-time mileage of the current driving cycle and the mileage of each historical driving cycle since the use of the sulfur trap 100 to obtain the total mileage;

The total driving mileage is compared with the driving mileage threshold, and when the total driving mileage is greater than or equal to the driving mileage threshold, it indicates that the sulfur trap 100 needs to be updated.

In this way, after the sulfur trap 100 is updated, the total mileage since the sulfur trap 100 is used needs to be reset to 0.

This embodiment provides a post-processing desulfurization system and a control strategy for the post-processing desulfurization system. The post-processing desulfurization system provided in this embodiment is arranged on the post-treatment of diesel engines, and the sulfur trap 100 is regularly updated, that is It can reduce the risk of SCR sulfur poisoning in the aftertreatment, and does not require high temperature desulfurization, thereby reducing the risk of SCR hydrothermal aging, and improving the reliability and fuel economy of the SCR catalyst in the aftertreatment system.

A control strategy of a post-treatment desulfurization system provided in this embodiment will be briefly described below with reference to FIG. 6 and FIG. 7 .

Step S41, obtain the initial value of sulfur mass flow rate in exhaust gas according to engine speed, fuel injection quantity and sulfur concentration in fuel;

Specifically, the initial value of the mass flow rate of sulfur in the exhaust gas may be obtained through calculation based on a relationship diagram between the engine speed and the fuel injection amount and the fuel sulfur content.

Step S42, correcting the initial value of the above-mentioned sulfur mass flow rate by using the influence coefficient of excess air to obtain the sulfur mass flow rate under transient working conditions;

Specifically, the air excess influence coefficient may be determined according to the relationship diagram between the air intake amount and the excess air influence coefficient, and the excess air influence coefficient is multiplied by the initial value of the sulfur mass flow rate to obtain the sulfur mass flow rate under the above transient conditions.

Step S43, further correcting the sulfur mass flow rate under the above-mentioned transient working conditions by using the ambient temperature influence coefficient;

Specifically, the ambient temperature influence coefficient can be determined according to the relationship diagram between the ambient temperature and the ambient temperature influence coefficient, and the ambient temperature influence coefficient can be multiplied by the sulfur mass flow rate under the above-mentioned transient conditions, so as to realize the calculation of the above-mentioned transient conditions. The sulfur mass flow rate is further corrected.

Step S44, further correcting the result obtained in step S43 by using the environmental pressure influence coefficient to obtain the mass flow rate of sulfur in the exhaust gas;

Specifically, the environmental pressure influence coefficient may be determined according to the relationship diagram between the environmental pressure and the environmental pressure influence coefficient, and the environmental pressure influence coefficient is multiplied by the result obtained in step S43 to obtain the mass flow rate of sulfur in the exhaust gas.

Step S45, integrating the mass flow rate of sulfur in the exhaust gas in the current driving cycle to obtain the integral value of the mass flow rate of sulfur in the current driving cycle;

Step S46 , multiplying the integral value by the conversion efficiency of the sulfur trap 100 to obtain the real-time sulfur trap quality.

Step S47, obtaining the sulfur capture quality of each historical driving cycle since the use of the sulfur trap 100;

Step S48, adding up the real-time sulfur capture mass and the sulfur capture mass of each historical driving cycle since the use of the sulfur trap 100 to obtain the total amount of sulfur capture;

Step S49 , comparing the total amount of captured sulfur with the threshold value of sulfur capture amount, and when the total amount of sulfur capture is greater than or equal to the threshold value of sulfur capture amount, it is indicated that the sulfur trap 100 needs to be updated.

Step S50 , after updating the sulfur trap 100 , reset the integral value calculated in the ECU, the total amount of sulfur captured by the sulfur trap 100 since its use, etc. to zero.

When comparing the obtained operating parameter information of the sulfur trap 100 with the corresponding threshold, including obtaining the total mileage since the use of the sulfur trap 100, and comparing the total mileage with the mileage threshold, an optional In the implementation mode, the control strategy of the post-treatment sulfur removal system provided in this embodiment includes the following steps:

The mileage of the current driving cycle and the mileage of each historical driving cycle since the use of the sulfur trap 100 are accumulated to obtain the total mileage;

The total driving mileage is compared with the driving mileage threshold, and when the total driving mileage is greater than or equal to the driving mileage threshold, it indicates that the sulfur trap 100 needs to be updated.

In an optional implementation, the mileage of the current driving cycle is accumulated with the mileage of each historical driving cycle since the use of the sulfur trap 100 to obtain the total mileage, which specifically includes the following steps:

Obtain the real-time driving mileage of the current driving cycle and the driving mileage of each historical driving cycle since the use of the sulfur trap 100;

The real-time driving mileage of the current driving cycle and the driving mileage of each historical driving cycle since the use of the sulfur trap 100 are accumulated to obtain the total driving mileage.

After updating the sulfur trap 100, reset the total mileage since the sulfur trap 100 was used to zero.

The situation when the post-treatment desulfurization system provided by this embodiment is arranged for the post-treatment of the diesel engine is briefly described below in conjunction with FIG. 8 :

The air enters the compressor 4 after passing through the filter 3, and then enters the engine 6 through the intake throttle valve 5. The exhaust gas discharged from the engine enters the turbine 7 after passing through the sulfur trap 100, and after being discharged from the turbine, it passes through the DOC (Diesel OxidationCatalysis, oxidation catalytic converter) 8, DPF (Diesel Particulate Filter, particulate matter trap) 9, SCR10, and ASC (ammonia oxidation catalyst) 13 are discharged, wherein, there will be urea injection between DPF and SCR .

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (12)

1. A post-treatment sulfur removal system, comprising: an engine, a turbine, and a sulfur trap, an exhaust of the engine being in communication with an intake of the sulfur trap, an exhaust of the sulfur trap being in communication with an intake of the turbine;

the control strategy applied to the aftertreatment sulfur removal system includes:

calculating the real-time sulfur trapping quality of the sulfur trap;

accumulating the real-time sulfur trapping quality and the sulfur trapping quality of each historical driving cycle used by the sulfur trap to obtain total sulfur trapping amount;

comparing the total sulfur trapping amount with a sulfur trapping amount threshold, and indicating that the sulfur trap needs to be updated when the total sulfur trapping amount is greater than or equal to the sulfur trapping amount threshold;

wherein, calculate the real-time sulfur capture quality of the sulfur trap, specifically include:

integrating the sulfur mass flow in the exhaust gas in the current driving cycle to obtain an integrated value of the sulfur mass flow in the current driving cycle;

and multiplying the integral value by the conversion efficiency of the sulfur trap to obtain the real-time sulfur trapping quality.

2. The aftertreatment sulfur removal system of claim 1, wherein the sulfur trap has a plurality of parallel channels, an air inlet of each of the channels communicates with an air outlet of the engine, an air outlet of each of the channels communicates with an air inlet of the turbine, and a wall of each of the channels is coated with a sulfur trap layer.

3. The aftertreatment sulfur removal system of claim 2, wherein the sulfur capture layer comprises a support layer and a sulfur capture agent.

4. The aftertreatment sulfur removal system of claim 3, wherein the sulfur capture agent comprises an alkali metal oxide and/or an alkaline earth metal oxide.

5. The aftertreatment sulfur removal system of claim 1, wherein the sulfur trap is removably connected to both an exhaust port of the engine and an intake port of the turbine.

6. A control strategy for an aftertreatment sulfur removal system, applied to the aftertreatment sulfur removal system of any of claims 1-5, the control strategy comprising:

calculating the real-time sulfur trapping quality of the sulfur trap;

accumulating the real-time sulfur capture quality and the sulfur capture quality of each historical driving cycle from the use of the sulfur trap to obtain the total sulfur capture amount;

comparing the total sulfur capture amount with the sulfur capture amount threshold, and indicating that the sulfur trap needs to be updated when the total sulfur capture amount is greater than or equal to the sulfur capture amount threshold;

wherein, calculate the real-time sulfur capture quality of the sulfur trap, specifically include:

integrating the sulfur mass flow in the exhaust gas in the current driving cycle to obtain an integrated value of the sulfur mass flow in the current driving cycle;

and multiplying the integral value by the conversion efficiency of the sulfur trap to obtain the real-time sulfur trapping quality.

7. The control strategy according to claim 6, characterized in that the integrating the mass flow of sulfur in the exhaust gas in the current driving cycle, before obtaining the integrated value of the mass flow of sulfur in the current driving cycle, comprises:

obtaining an initial value of sulfur mass flow in the exhaust gas through the rotation speed of the engine and the injection quantity of the fuel oil and the sulfur concentration in the fuel oil;

and correcting the initial value of the sulfur mass flow to obtain the sulfur mass flow in the exhaust gas.

8. The control strategy of claim 7, wherein the means for modifying the initial value of the sulfur mass flow comprises at least one of:

correcting the initial value of the sulfur mass flow through an air excess influence coefficient;

correcting the initial value of the sulfur mass flow through an environmental temperature influence coefficient;

and correcting the initial value of the sulfur mass flow through the environmental pressure influence coefficient.

9. The control strategy according to any one of claims 6-8, characterized in that said accumulating said real-time sulfur capture quality with the sulfur capture quality of each historical driving cycle since the use of the sulfur trap, in particular comprises:

obtaining the sulfur trapping quality of each historical driving cycle or the sum of the sulfur trapping quality of each historical driving cycle;

and accumulating the real-time sulfur capture quality and the corresponding sulfur capture quality of each historical driving cycle or the sum of the sulfur capture quality of each historical driving cycle.

10. The control strategy according to any one of claims 6-8, characterized in that the real-time sulfur capture mass is stored after the end of the current driving cycle to calculate the total sulfur capture of the sulfur trap in the next driving cycle.

11. The control strategy of any of claims 6-8, further comprising:

accumulating the real-time driving mileage of the current driving cycle and the driving mileage of each historical driving cycle used by the sulfur trap to obtain the total driving mileage;

and comparing the total driving mileage with a driving mileage threshold value, and indicating that the sulfur trap needs to be updated when the total driving mileage is greater than or equal to the driving mileage threshold value.

12. The control strategy of any of claims 6-8, further comprising:

obtaining a sulfur escape concentration, and comparing the sulfur escape concentration with a sulfur concentration threshold;

and when the sulfur escape concentration is greater than or equal to a sulfur concentration threshold, indicating that the sulfur trap needs to be updated.

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