# US 12,000,321 B1 · Systems and methods to reduce methane emissions associated with a lean-burn natural gas engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,321 B1 - Document ID: US12000321B1 - Status: Granted - Kind: B1 - Application number: 18/172,930 - Filed: 2023-02-22 - Granted: 2024-06-04 - Earliest claimed: 2023-02-22 - Assignees: Caterpillar Inc. - Applicants: Caterpillar Inc. - Inventors: Zachary J. Wilks - Web page: https://patentgrep.com/patent/US12000321B1 ## CPC - F01N 3/24: characterised by constructional aspects of converting apparatus (filtering in combination with catalytic reactors F01N3/035) - F01N 3/101: {Three-way catalysts} - F01N 3/2013: {using electric or magnetic heating means} - F01N 3/2066: {Selective catalytic reduction [SCR]} - 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 5/025: {the device being thermoelectric generators} - F01N 2240/16: an electric heater, i.e. a resistance heater - F01N 2260/02: for cooling the device - F01N 2900/1602: Temperature of exhaust gas apparatus - 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) ## Abstract An engine system includes a lean-burn natural gas engine, an electric power supply component, an aftertreatment housing, and a heating component within the aftertreatment housing. The lean-burn natural gas engine provides, when in operation, an exhaust gas that includes methane to an input end of the aftertreatment housing. The aftertreatment housing allows the exhaust gas to flow through the aftertreatment housing from the input end of the aftertreatment housing to an output end of the aftertreatment housing. The electric power supply component provides, to the heating component, electric power that is generated using one or more low-carbon generation techniques. The heating component generates, based on the electric power provided by the electric power supply component, heat, and provides the heat within the aftertreatment housing. This causes a percentage of methane in the exhaust gas that flows through the aftertreatment housing to be reduced. ## Claims ### Claim 1 A system, comprising: a lean-burn natural gas engine; an electric power supply component that includes one or more of one or more thermoelectric generators, one or more batteries, one or more battery packs, one or more battery strings, one or more battery modules, or one or more battery cells; and an aftertreatment housing including: a catalyst, and a heating component that includes an electrically driven heater, wherein: the lean-burn natural gas engine is configured to provide, when in operation, an exhaust gas to an input end of the aftertreatment housing, the aftertreatment housing is configured to allow the exhaust gas to flow through the aftertreatment housing from the input end of the aftertreatment housing to an output end of the aftertreatment housing, the electric power supply component is configured to provide, to the heating component, electric power that is generated using one or more low-carbon generation techniques, and a controller is configured to: when the electric power supply component is not actively providing the electric power to the heating component, determine a state of charge (SoC) for the electric power supply component; one of: cause, when the SoC satisfies a threshold, the electric power supply component to be enabled to operate and provide the electric power to the heating component, or cause, when the SoC does not satisfy the threshold, the electric power supply component to be disabled from providing the electric power to the heating component; and cause the heating component to provide, based on the electric power actively provided by the electric power supply component, heat within the aftertreatment housing to cause a temperature associated with an internal environment of the aftertreatment housing to satisfy a temperature threshold associated with enabling a conversion process that reduces methane emissions within the exhaust gas. ### Claim 2 (depends on 1) The system of claim 1, wherein: a percentage of methane in the exhaust gas after the exhaust gas exits the aftertreatment housing via the output end of the aftertreatment housing is less than a percentage of methane in the exhaust gas before the exhaust gas enters the aftertreatment housing via the input end of the aftertreatment housing. ### Claim 3 (depends on 1) The system of claim 1, wherein the temperature associated with the internal environment of the aftertreatment housing satisfies the temperature threshold when the temperature associated with the internal environment of the aftertreatment housing is greater than or equal to 500 degrees Celsius. ### Claim 4 (depends on 1) The system of claim 1, wherein the temperature associated with the internal environment of the aftertreatment housing is at least one of: a temperature associated with the exhaust gas within the aftertreatment housing, or a temperature associated with the catalyst of the aftertreatment housing. ### Claim 5 (depends on 1) The system of claim 1, wherein the lean-burn natural gas engine generates first heat as a result of the operation of the lean-burn natural gas engine, and the heat provided by the heating component is a second heat, and wherein the electric power supply component is configured to: generate, using a thermoelectric generation technique and based on the first heat, the electric power. ### Claim 6 (depends on 5) The system of claim 5, wherein the first heat is provided to the electric power supply component via a cooling system associated with the lean-burn natural gas engine. ### Claim 7 (depends on 5) The system of claim 5, wherein a first temperature associated with the first heat is less than a second temperature associated with the second heat. ### Claim 8 (depends on 1) The system of claim 1, wherein the electric power supply component includes the one or more batteries. ### Claim 9 (depends on 1) The system of claim 1, wherein the one or more low-carbon generation techniques include at least one of: a thermoelectric generation technique; a hydroelectric generation technique; a wind power generation technique; a solar power generation technique; a geothermal power generation technique; or a nuclear power generation technique. ### Claim 10 A system, comprising: a controller; an electric power supply component; an aftertreatment housing; and a heating component within the aftertreatment housing, wherein: the heating component includes an electrically driven heater, the aftertreatment housing is configured to allow exhaust gas, generated by a lean-burn natural gas engine, to flow through the aftertreatment housing from an input end of the aftertreatment housing to an output end of the aftertreatment housing, the electric power supply component is configured to provide, to the heating component, electric power that is generated using one or more low-carbon generation techniques; and the controller is configured to: when the electric power supply component is not actively providing the electric power to the heating component, determine a state of charge (SoC) for the electric power supply component; at least one of: cause, when the SoC satisfies a threshold, the electric power supply component to be enabled to operate and provide the electric power to the heating component, or cause, when the SoC does not satisfy the threshold, the electric power supply component to be disabled from providing the electric power to the heating component; and cause the heating component to provide, based on the electric power actively provided by the electric power supply component, heat within the aftertreatment housing to cause a temperature associated with an internal environment of the aftertreatment housing to satisfy a temperature threshold associated with enabling a conversion process that reduces methane emissions within the exhaust gas. ### Claim 11 (depends on 10) The system of claim 10, wherein: a percentage of methane in the exhaust gas after the exhaust gas exits the aftertreatment housing via the output end of the aftertreatment housing is less than a percentage of methane in the exhaust gas before the exhaust gas enters the aftertreatment housing via the input end of the aftertreatment housing. ### Claim 12 (depends on 10) The system of claim 10, wherein the electric power supply component is configured to generate, using a thermoelectric generation technique, the electric power based on other heat generated as a result of generation of the exhaust gas by the lean-burn natural gas engine. ### Claim 13 (depends on 12) The system of claim 12, wherein the electric power supply component is configured to obtain the other heat via a cooling system associated with the lean-burn natural gas engine. ### Claim 14 (depends on 10) The system of claim 10, wherein the electric power supply component includes at least one of: one or more thermoelectric generators, or one or more batteries. ### Claim 15 A system, comprising: an electric power supply component; and a heating component within an aftertreatment housing, wherein: the heating component includes an electrically driven heater, the electric power supply component is configured to provide, to the heating component, electric power that is generated using one or more low-carbon generation techniques, a controller is configured to: when the electric power supply component is not actively providing the electric power to the heating component, determine a state of charge (SoC) for the electric power supply component; at least one of: cause, when the SoC satisfies a threshold, the electric power supply component to be enabled to operate and provide the electric power to the heating component, or cause, when the SoC does not satisfy the threshold, the electric power supply component to be disabled from providing the electric power to the heating component; and cause the heating component to provide, based on the electric power actively provided by the electric power supply component, heat within the aftertreatment housing to cause a temperature associated with an internal environment of the aftertreatment housing to satisfy a temperature threshold associated with enabling a conversion process that reduces methane emissions within exhaust gas, and the exhaust gas is generated by a lean-burn natural gas engine. ### Claim 16 (depends on 15) The system of claim 15, wherein the electric power supply component includes at least one of: one or more thermoelectric generators, or one or more batteries. ### Claim 17 (depends on 15) The system of claim 15, wherein the electric power supply component is configured to generate the electric power based on other heat generated as a result of generation of the exhaust gas by the lean-burn natural gas engine. ### Claim 18 (depends on 17) The system of claim 17, wherein the electric power supply component is configured to obtain the other heat via a cooling system associated with the lean-burn natural gas engine. ### Claim 19 (depends on 15) The system of claim 15, wherein the electric power supply component includes one or more batteries, and wherein the SoC is a SoC of the one or more batteries. ### Claim 20 (depends on 15) The system of claim 15, wherein the threshold is a battery charge percentage threshold, and wherein the controller is further configured to: determine that the electric power supply component is to be enabled based on the SoC satisfying the battery charge percentage threshold.