# US 2014/0360169 A1 · POST THERMAL CONTROL DEVICE FOR USE WITH A NOx SLIP CATALYST > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0360169 A1 - Document ID: US20140360169A1 - Status: Published application - Kind: A1 - Application number: 14/372,483 - Filed: 2012-01-19 - Published: 2014-12-11 - Earliest claimed: 2012-01-19 - Assignees: International Engine Intellectual Property Company, LLC - Inventors: Adam C. Lack - Web page: https://patentgrep.com/patent/US20140360169A1 ## CPC - F01N 3/208: {Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent} - F01N 3/0231: {using special exhaust apparatus upstream of the filter for producing nitrogen dioxide, e.g. for continuous filter regeneration systems [CRT]} - F01N 3/103: {Oxidation catalysts for HC and CO only} - 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 11/00: Monitoring or diagnostic devices for exhaust-gas treatment apparatus - F01N 2610/02: the substance being ammonia or urea - F01N 2610/06: the substance being in the gaseous form - Y02A 50/20: Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters - 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) - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A system and method for treating diesel exhaust in a diesel exhaust system, and specifically for improved NOx conversion efficiency during particulate filter regeneration, is disclosed. The exhaust gas treatment system includes a diesel oxidation catalyst (DOC); a diesel particulate filter (DPF) fluidly coupled to the DOC; a mixer fluidly coupled to the DOC and DPF, a thermal control device (TCD) positioned after the DPF, a NOx slip catalyst (NSC), at least one temperature sensor (TS), wherein the thermal control device reduces the temperature of the exhaust gas stream. The thermal control device used in conjunction with the NOx slip catalyst provides for improved overall exhaust system NOx conversion efficiency during active DPF regeneration. ## Claims ### Claim 1 A method for reducing NOx in an exhaust gas stream of a diesel-engine vehicle, the method comprising the steps of: fluidly coupling components of an exhaust gas treatment system package to an engine exhaust gas system; flowing a heated exhaust stream through the exhaust gas treatment system package; injecting gaseous ammonia into the exhaust gas treatment system package; reducing an outgoing temperature of engine exhaust gas after the exhaust passes through the system package; and, reducing the NOx to an acceptable level. ### Claim 2 (depends on 1) The method of claim 1, wherein the components of the exhaust gas treatment system package comprise a mixing chamber for reacting the gaseous ammonia with the exhaust gas stream to reduce NOx in the exhaust gas. ### Claim 3 (depends on 2) The method of claim 2, wherein the components of the exhaust gas treatment system package further comprise: a diesel oxidation catalyst (DOC); a diesel particulate filter (DPF); a thermal control device (TCD); a NOx slip catalyst (NSC); and, at least one temperature sensor (TS); wherein the DOC, DPF, TCD, TS and NSC are all fluidly coupled together and to the mixing chamber, and wherein the TCD operates in conjunction with the NSC to effectively reduce the amount of NOx in the exhaust stream. ### Claim 4 (depends on 3) The method of claim 3, wherein the thermal control device is positioned before the NSC. ### Claim 5 (depends on 3) The method of claim 3, wherein at least one of the temperature sensors is positioned after the thermal control device and before the NSC. ### Claim 6 (depends on 3) The method of claim 3, wherein at least one of the temperature sensors is positioned before the thermal control device. ### Claim 7 (depends on 1) The method of claim 1, wherein the step of reducing an outgoing temperature of engine exhaust gas prior to entry into a NOx slip catalyst (NSC) includes installation of a thermal control device (TCD) before the NSC. ### Claim 8 (depends on 7) The method of claim 7, wherein the step of reducing an outgoing temperature of engine exhaust gas prior to entry into a NOx slip catalyst (NSC) includes installation of a thermal control device (TCD) after the DPF. ### Claim 9 An exhaust gas treatment system for use in reducing NOx in an exhaust gas stream of a diesel-engine vehicle, the system comprising: a diesel oxidation catalyst (DOC); a mixer fluidly coupled to the DOC; a diesel particulate filter (DPF) fluidly coupled to the mixer and DOC; a thermal control device (TCD) positioned after the DPF; a NOx slip catalyst (NSC) positioned downstream from the DPF; and, at least one temperature sensor (TS) positioned in conjunction with one of the TCD and NSC, wherein the TCD operates in conjunction with the at least one temperature sensor to reduce the temperature of the exhaust gas stream prior to entry into the NSC. ### Claim 10 (depends on 9) The exhaust gas treatment system of claim 9, wherein the temperature sensor is positioned after the NSC. ### Claim 11 (depends on 9) The exhaust gas treatment system of claim 9, wherein a first temperature sensor is positioned before the NSC, and a second temperature sensor is located after the NSC. ### Claim 12 (depends on 9) The exhaust gas treatment system of claim 9, wherein the thermal control device is an exhaust temperature reducing device. ### Claim 13 (depends on 9) The exhaust gas treatment system of claim 9, wherein the temperature sensor interacts with the thermal control device to reduce exhaust temperatures to a desired level. ### Claim 14 A method for reducing NOx in an exhaust gas stream in a diesel-engine vehicle after particulate filter regeneration, the method comprising: fluidly coupling components of an exhaust gas treatment system package to an engine exhaust gas system; applying superheated exhaust gas into the exhaust gas treatment system package for filter regeneration; injecting gaseous ammonia into the exhaust gas treatment system package for NOx reduction; incorporating a NOx slip catalyst (NSC) into the exhaust gas treatment system; reducing the temperature of the exhaust gas prior to entry into the NSC; and, further reducing the level of NOx to an acceptable level. ### Claim 15 (depends on 14) The method of claim 14, wherein the components of the exhaust gas treatment system package further comprise: a diesel oxidation catalyst (DOC); a diesel particulate filter (DPF); a thermal control device (TCD); and, at least one temperature sensor (TS); wherein the DOC, DPF, TCD, TS and NSC are all fluidly coupled together and to the mixing chamber, and wherein the TCD operates to reduce the temperature of the superheated exhaust gas. ### Claim 16 (depends on 15) The method of claim 15, wherein the TCD operates in conjunction with the NSC to effectively reduce the amount of NOx in the exhaust stream.