# US 8,783,018 B2 · Reductant storage sensing system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,018 B2 - Document ID: US8783018B2 - Status: Granted - Kind: B2 - Application number: 13/431,367 - Filed: 2012-03-27 - Published: 2012-07-19 - Granted: 2014-07-22 - Earliest claimed: 2006-03-03 - Assignees: Ford Global Technologies, LLC - Applicants: David John Kubinski; Devesh Upadhyay - Inventors: David John Kubinski; Devesh Upadhyay - Web page: https://patentgrep.com/patent/US8783018B2 ## CPC - B01D 53/9431: {Processes characterised by a specific device} - B01D 53/9495: {Controlling the catalytic process} - F01N 3/206: {Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents} - F01N 3/208: {Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent} - F01N 13/009: {having two or more separate purifying devices arranged in series} - F01N 2240/16: an electric heater, i.e. a resistance heater - F01N 2510/063: zeolites - F01N 2550/03: of sorbing activity of adsorbents or absorbents - F01N 2560/021: for measuring or detecting ammonia NH3 - F01N 2560/14: having more than one sensor of one kind - F01N 2570/18: Ammonia - F01N 2610/02: the substance being ammonia or urea - F01N 2900/0418: using integration or an accumulated value within an elapsed period - F01N 2900/1622: Catalyst reducing agent absorption capacity or consumption amount - Y02T 10/12: Improving ICE efficiencies - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - 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) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A catalyst supported on a substrate includes a heater embedded in a sub-region of the substrate to heat a local region of the catalyst. The amount of ammonia stored on the catalyst may be determined and controlled through conductivity measurements in the locally heated portion of the system described. ## Claims ### Claim 1 A method of sensing operation of an SCR engine exhaust treatment device having base-metal-zeolite supported on a substrate, comprising: increasing temperature of a sub-region of the substrate; monitoring a change by sensing a conductivity of the base-metal-zeolite local to the sub-region; and outputting information based on said monitored change including correlating the change to an amount of stored ammonia in the base-metal-zeolite local to the sub-region. ### Claim 2 (depends on 1) The method of claim 1 wherein said monitoring includes monitoring electrodes coupled in the sub-region of the substrate. ### Claim 3 (depends on 1) The method of claim 1 where temperature is increased to a preselected value by applying heat to the sub-region of the substrate. ### Claim 4 (depends on 3) The method of claim 3 wherein an amount of heat supplied is varied with operating conditions. ### Claim 5 (depends on 1) The method of claim 1 wherein temperature is increased to substantially remove reductant stored on the base-metal-zeolite local to the sub-region, without removing ammonia stored in a remaining region of the base-metal-zeolite. ### Claim 6 (depends on 5) The method of claim 5 wherein the information is correlated to an amount of ammonia stored throughout the SCR engine exhaust treatment device. ### Claim 7 (depends on 6) The method of claim 6 further comprising varying an amount of reductant injected into the device to vary a level of storage in response to the information. ### Claim 8 (depends on 7) The method of claim 7 further comprising applying an oscillating voltage signal to electrodes located in the sub-region of the substrate. ### Claim 9 (depends on 8) The method of claim 8 further comprising integrating a resulting current generated by the oscillating voltage signal. ### Claim 10 (depends on 9) The method of claim 9, wherein said output information is based on said integrated current. ### Claim 11 A method of controlling engine operation, an engine having an SCR emission control device coupled in an engine exhaust, comprising: estimating an amount of ammonia stored in the SCR emission control device based on an operating condition by locally increasing temperature of a sub-region of the device, the temperature increased by supplying heat, wherein an amount of heat supplied is varied with operating parameters; measuring ammonia storage in the sub-region of the device and correlating said measure to an amount of ammonia stored throughout the SCR emission control device; and adjusting an amount of reductant injection into the exhaust based on said estimated and measured amounts. ### Claim 12 A method of sensing operation of an SCR engine exhaust treatment device having a base-metal-zeolite supported on a substrate, comprising: increasing temperature of a sub-region of the substrate to substantially remove reductant stored on the base-metal-zeolite local to the sub-region, without removing ammonia stored in a remaining region of the base-metal-zeolite; monitoring a change in conductivity of the base-metal-zeolite local to the sub-region; and outputting information based on said monitored conductivity change. ### Claim 13 (depends on 12) The method of claim 12 wherein outputting information based on said monitored conductivity change includes correlating the conductivity change to an amount of stored ammonia in the base-metal-zeolite local to the sub-region.