# US 11,898,480 B2 · Methods and systems for removing deposits in an aftertreatment system to minimize visible smoke emissions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,898,480 B2 - Document ID: US11898480B2 - Status: Granted - Kind: B2 - Application number: 17/902,241 - Filed: 2022-09-02 - Published: 2022-12-29 - Granted: 2024-02-13 - Earliest claimed: 2017-04-28 - Assignees: Cummins Inc. - Applicants: Cummins Inc. - Inventors: Todd C. Bouws; Ankit Raghunath Lad; Joshua A. Lantz; Boopathi Singalandapuram Mahadevan; Ian W. McGiffen; Douglas A. Roxbury - Web page: https://patentgrep.com/patent/US11898480B2 ## CPC - F01N 3/025: using fuel burner or by adding fuel to exhaust - F02D 41/029: {the exhaust gas treating apparatus being a particulate filter} - F01N 3/103: {Oxidation catalysts for HC and CO only} - F01N 3/106: {Auxiliary oxidation catalysts} - F01N 3/2066: {Selective catalytic reduction [SCR]} - F01N 3/24: characterised by constructional aspects of converting apparatus (filtering in combination with catalytic reactors F01N3/035) - F01N 9/002: {of filter regeneration} - F01N 13/009: {having two or more separate purifying devices arranged in series} - F02D 41/04: Introducing corrections for particular operating conditions (F02D41/14 takes precedence) - F02D 41/1466: {the characteristics being a soot concentration or content} - F02D 41/16: for idling - F01N 9/00: Electrical control of exhaust gas treating apparatus (monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00) - F01N 2610/03: the substance being hydrocarbons, e.g. engine fuel - F01N 2900/08: said parameters being related to the engine - F01N 2900/1606: Particle filter loading or soot amount - F02D 41/0245: {by increasing temperature of the exhaust gas leaving the engine} - F02D 41/08: for idling (F02D41/06, F02D41/16 take precedence) - F02D 41/1445: {the characteristics being related to the exhaust flow} - F02D 41/1446: {the characteristics being exhaust temperatures} - F02D 41/18: by measuring intake air flow - F02D 2200/0812: Particle filter loading - F02D 2200/1002: Output torque - Y02T 10/12: Improving ICE efficiencies - Y02T 10/40: Engine management systems - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Systems and methods for removing accumulated soot in an aftertreatment system are disclosed herein. A method includes: determining, by a controller, an adsorption amount of soot in an exhaust aftertreatment system; comparing, by the controller, the adsorption amount of soot to a predefined adsorption amount limit; in response to the adsorption amount exceeding the predefined adsorption amount limit, initiating, by the controller, an exhaust cleaning event to remove at least some accumulated soot in the exhaust aftertreatment system; receiving, by the controller, exhaust gas data during the exhaust cleaning event; determining, by the controller, a desorption amount of soot based on the exhaust gas data; comparing, by the controller, the desorption amount of soot to a predefined desorption limit; and ceasing, by the controller, the exhaust cleaning event based on the comparison. ## Claims ### Claim 1 A method, comprising: receiving, by a controller, data regarding an exhaust gas flow rate of exhaust gas at a particular location and an amount of soot in the exhaust gas at the particular location in an exhaust aftertreatment system, wherein the particular location in the exhaust aftertreatment system is a selective catalytic reduction (SCR) inlet; determining, by the controller, an adsorption amount of soot in the exhaust aftertreatment system based on the exhaust gas flow rate of the exhaust gas at the particular location and the amount of soot in the exhaust gas at the particular location; comparing, by the controller, the adsorption amount of soot to a predefined adsorption amount limit; in response to the adsorption amount of soot exceeding the predefined adsorption amount limit, initiating, by the controller, an exhaust cleaning event to remove at least some accumulated soot in the exhaust aftertreatment system; receiving, by the controller, exhaust gas data during the exhaust cleaning event; determining, by the controller, a desorption amount of soot based on the exhaust gas data, wherein a buffer is applied to determine the desorption amount, and wherein the buffer is a predefined period of time the exhaust data is collected before the desorption amount of soot is determined; comparing, by the controller, the desorption amount of soot to a predefined desorption limit; and ceasing, by the controller, the exhaust cleaning event based on the comparison. ### Claim 2 (depends on 1) The method of claim 1, further comprising: receiving, by the controller, an indication that an engine has been operating in a low load condition for more than a predefined amount of time and determining the adsorption amount of soot in the exhaust aftertreatment system in response to the engine being operating in the low load condition for more than the predefined amount of time. ### Claim 3 (depends on 2) The method of claim 2, wherein the low load condition is an idle state for the engine. ### Claim 4 (depends on 3) The method of claim 3, wherein the low load condition corresponds with an engine speed of less than approximately 1300 RPM and the predefined amount of time is between approximately 4.5 hours and 8.5 hours. ### Claim 5 (depends on 1) The method of claim 1, wherein the exhaust cleaning event includes at least one of opening an exhaust valve, opening an intake air valve, or turning on an exhaust aftertreatment system heater. ### Claim 6 (depends on 1) The method of claim 1, further comprising: in response to the adsorption amount of soot exceeding the predefined adsorption amount limit by a predetermined value, initiating, by the controller, a first power demand state; and in response to the adsorption amount of soot exceeding the predefined adsorption amount limit by less than the predetermined value, initiating, by the controller, a second power demand state different from the first power demand state. ### Claim 7 (depends on 6) The method of claim 6, wherein the first power demand state is associated with a relatively greater power output from an engine coupled to the exhaust aftertreatment system than the second power demand state. ### Claim 8 A non-transitory computer-readable media storing instructions therein that, when executed by at least one processor, causes the at least one processor to perform operations comprising: receiving data regarding an exhaust gas flow rate of exhaust gas at a particular location and an amount of soot in the exhaust gas at the particular location in an exhaust aftertreatment system, wherein the particular location in the exhaust aftertreatment system is a selective catalytic reduction (SCR) inlet; determining an adsorption amount of particulate matter in the exhaust aftertreatment system coupled to an engine based on the exhaust gas flow rate of the exhaust gas at the particular location and the amount of soot in the exhaust gas at the particular location; comparing the adsorption amount of particulate matter to a predefined adsorption amount limit; in response to the adsorption amount of particulate matter exceeding the predefined adsorption amount limit, initiating an exhaust cleaning event to remove at least some particulate matter from the exhaust aftertreatment system; receiving exhaust gas data during the exhaust cleaning event; determining a desorption amount of particulate matter based on the exhaust gas data, wherein a buffer is applied to determine the desorption amount, and wherein the buffer is a predefined period of time the exhaust data is collected before the desorption amount of soot is determined; comparing the desorption amount of particulate matter to a predefined desorption limit; and ceasing the exhaust cleaning event based on the comparison. ### Claim 9 (depends on 8) The computer-readable media of claim 8, wherein the exhaust cleaning event includes at least one of opening an exhaust valve, opening an intake air valve, or turning on an exhaust gas heater. ### Claim 10 (depends on 8) The computer-readable media of claim 8, wherein the instructions, when executed by the at least one processor, further cause operations comprising receiving data regarding operation of the engine that indicates operating in a low load condition for more than a predefined amount of time. ### Claim 11 (depends on 10) The computer-readable media of claim 10, wherein the exhaust cleaning event includes increasing a power output from the engine relative to a power output from the engine in the low load condition. ### Claim 12 (depends on 11) The computer-readable media of claim 11, wherein increasing the power output includes increasing a notch setting of the engine to a notch three setting or higher. ### Claim 13 (depends on 8) The computer-readable media of claim 8, wherein the instructions, when executed by the at least one processor, further cause operations comprising: in response to the adsorption amount of particulate matter exceeding the predefined adsorption amount limit by a predetermined value, initiating a first power demand state; and in response to the adsorption amount of particulate matter exceeding the predefined adsorption amount limit by less than the predetermined value, initiating a second power demand state different from the first power demand state. ### Claim 14 (depends on 13) The computer-readable media of claim 13, wherein the first power demand state is associated with a relatively greater power output from the engine than the second power demand state. ### Claim 15 (depends on 8) The computer-readable media of claim 8, wherein the instructions, when executed by the at least one processor, further cause operations comprising: retrieving a look-up table regarding the exhaust gas flow rate to determine an adsorption rate; determining the adsorption rate of particulate matter in the exhaust aftertreatment system based at least partly on the exhaust gas flow rate using the look-up table; and determining the adsorption amount of particulate matter based on the adsorption rate. ### Claim 16 (depends on 15) The computer-readable media of claim 15, wherein the instructions, when executed by the at least one processor, further cause operations comprising utilizing at least one of a determined particulate matter amount and an inlet temperature regarding a selective catalytic reduction device in the exhaust aftertreatment system in combination with the exhaust gas flow rate in the look-up table to determine the adsorption rate. ### Claim 17 A system, comprising: a controller coupled to an engine and an exhaust aftertreatment system, the controller comprising at least one processing circuit comprising at least one memory coupled to at least one processor, the controller structured to: receive data regarding an exhaust gas flow rate of exhaust gas at a particular location and an amount of soot in the exhaust gas at the particular location in an exhaust aftertreatment system, wherein the particular location in the exhaust aftertreatment system is a selective catalytic reduction (SCR) inlet; determine an adsorption amount of particulate matter in the exhaust aftertreatment system based on the exhaust gas flow rate of the exhaust gas at the particular location and the amount of soot in the exhaust gas at the particular location; compare the adsorption amount of particulate matter to a predefined adsorption amount limit; in response to the adsorption amount of particulate matter exceeding the predefined adsorption amount limit, initiate an exhaust cleaning event to remove at least some accumulated particulate matter in the exhaust aftertreatment system; receive exhaust gas data during the exhaust cleaning event; determine a desorption amount of particulate matter based on the exhaust gas data, wherein a buffer is applied to determine the desorption amount, and wherein the buffer is a predefined period of time the exhaust data is collected before the desorption amount of soot is determined; compare the desorption amount of particulate matter to a predefined desorption limit; and cease the exhaust cleaning event based on the comparison. ### Claim 18 (depends on 17) The system of claim 17, wherein the exhaust aftertreatment system does not include a particulate filter. ### Claim 19 (depends on 17) The system of claim 17, wherein the controller is further structured to receive data regarding operation of an engine coupled to the exhaust aftertreatment system indicating that the engine is operating in a low load condition for more than a predefined amount of time. ### Claim 20 (depends on 17) The system of claim 17, wherein the exhaust cleaning event includes at least one of opening an exhaust valve, opening an intake air valve, or adjusting operation of a turbocharger to increase a flow rate of exhaust gas through the exhaust aftertreatment system.