# US 10,758,753 B2 · Ducting system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,758,753 B2 - Document ID: US10758753B2 - Status: Granted - Kind: B2 - Application number: 15/764,206 - Filed: 2016-10-27 - Published: 2018-09-27 - Granted: 2020-09-01 - Earliest claimed: 2015-10-30 - Assignees: Commonwealth Scientific and Industrial Research Organisation - Applicants: Commonwealth Scientific and Industrial Research Organisation - Inventors: Shi Su; Hua Guo; Xinxiang Yu - Web page: https://patentgrep.com/patent/US10758753B2 ## CPC - A62C 3/06: of highly inflammable material, e.g. light metals, petroleum products - A62C 4/02: in gas-pipes (safety valves F16K17/00) - E21F 1/00: Ventilation of mines or tunnels; Distribution of ventilating currents (ventilating rooms or spaces in general F24F) - E21F 7/00: Methods or devices for drawing- off gases with or without subsequent use of the gas for any purpose - F23G 7/06: of waste gases or noxious gases, e.g. exhaust gases (exhaust apparatus for engines with means for rendering the exhaust innocuous, e.g. by thermal or catalytic conversion, F01N3/08; combustion of uncombusted material from primary combustion within apparatus for combustion of solid or fluent fuel F23B {, of non combusted material from primary combustion of solid fuels; of gases produced by primary combustion of solid fuels F23B90/04}, F23C) - F23N 5/24: Preventing development of abnormal or undesired conditions, i.e. safety arrangements (F23N5/02 - F23N5/18 take precedence) - F23G 2204/103: gaseous or liquid fuel - F23G 2208/10: Preventing or abating fire or explosion, e.g. by purging - F23G 2209/141: Explosive gases - F23N 2231/28: preventing flash-back or blow-back - A62C: FIRE-FIGHTING (fire-extinguishing compositions, use of chemical substances in extinguishing fires A62D1/00; spraying, applying liquids or other fluent materials to surfaces in general B05; alarm arrangements G08B, e.g. fire alarms actuated by smoke or gases G08B17/10) - E21F: SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS - F23G: CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION - F23N: REGULATING OR CONTROLLING COMBUSTION (control devices specially adapted for combustion apparatus in which combustion takes place in a fluidised bed of fuel or other particles F23C10/28; condition responsive controls for regulating combustion in domestic stoves with open fires for solid fuel F24B1/187) ## Abstract The present invention relates to a ducting system (100) for conveying a flow of a gaseous feed (110) comprising a combustible component from an inlet to at least one combustion module (12), the ducting system (100) utilising a combination of a sensor (C0) for measuring the concentration of the combustible component in the gaseous feed (110), a flame detector (F0, F1, F2, F3, . . . , Fn) a shut-off valve (6) and a flame arrestor (5) located in a flow path of the gaseous feed upstream of the shut-off valve (6) such that a measurement of a concentration of combustible material in the gaseous feed over a specified concentration by the sensor (CO) causes the shut-off valve (6) to be configured to the closed position for preventing flow of a gaseous feed comprising a combustible mixture of the combustible component from reaching an ignition source and/or detection of flame by the flame detector (F0, F1, F2, F3, . . . , Fn) causes shut-off valve (6) to be configured to the closed position for attenuating propagation of a flame towards the inlet. ## Claims ### Claim 1 A ducting system for conveying a flow of a gaseous feed of ventilation air derived from a coal mine comprising a combustible component from an inlet to at least one combustion module, the system comprising: a shut-off valve configurable to have an open position to allow the flow of the gaseous feed from the inlet to the at least one combustion module and a closed position to prevent the flow of the gaseous feed from the inlet to the at least one combustion module; a sensor to measure a concentration of the combustible component in the flow of the gaseous feed, the sensor located upstream of the shut-off valve; a flame detector located downstream of the shut-off valve; a flame arrestor located in a flow path of the gaseous feed upstream of the shut-off valve; and a source of fire retardant and a fire retardant valve feeding one or more fire retardant injection points for controlling flow of the fire retardant into the ducting system, the one or more fire retardant injection points positioned between the flame arrestor and the at least one combustion module, wherein the shut-oft valve is operatively associated with the sensor such that a measurement of a concentration of the combustible component in flow of the gaseous feed over a specified concentration by the sensor causes the shut-off valve to be configured to the closed position for preventing flow of a gaseous feed comprising a combustible mixture of the combustible component from reaching an ignition source, wherein the specified concentration is 1.25% methane as the combustible component wherein the shut-off valve is operatively associated with the flame detector such that detection of flame by the flame detector causes the shut-off valve to be configured to the closed position for attenuating propagation of a flame toward the inlet, and wherein the fire retardant valve is operatively associated with the flame detector such that detection of flame by the flame detector causes the fire retardant valve to open allowing the tire retardant to flow into the ducting system for attenuating the detected flame; further comprising a supplementary gaseous feed comprising a supplementary combustible component and a supplementary gaseous feed valve for controlling flow of supplementary gaseous feed into the flow of the gaseous feed downstream of the shut-off valve, wherein the supplementary gaseous feed is in fluid communication with a gas mixer for mixing the gaseous feed with the supplementary gaseous feed. ### Claim 2 A ducting system for conveying a flow of a gaseous feed of ventilation air derived from a coal mine comprising a combustible component from an inlet to at least one combustion module, the system comprising: a sensor to measure a concentration of the combustible component in the flow of the gaseous feed; a flame detector; a shut-off valve configurable to have an open position to allow the flow of the gaseous feed from the inlet to the at least one combustion module and a closed position to prevent the flow of the gaseous feed from the inlet to the at least one combustion module; and a flame arrestor located in a flow path of the gaseous feed upstream of the shut-oft valve, wherein the shut-off valve is operatively associated with the sensor such that a measurement of a concentration of the combustible component in flow of the gaseous feed over a specified concentration by the sensor causes the shut-off valve to be configured to the closed position for preventing flow of a gaseous feed comprising a combustible mixture of the combustible component from reaching an ignition source, wherein the specified concentration is 1.25% methane as the combustible component; and wherein the shut-off valve is operatively associated with the flame detector such that detection of flame by the flame detector causes the shut-off valve to be configured to the closed position for attenuating propagation of a flame toward the inlet; further comprising a supplementary gaseous feed comprising a supplementary combustible component and a supplementary gaseous feed valve for controlling flow of supplementary gaseous feed into the flow of the gaseous feed downstream of the shut-off valve, wherein the supplementary gaseous feed is in fluid communication with a gas mixer for mixing the gaseous feed with the supplementary gaseous feed. ### Claim 3 (depends on 2) The system according to claim 2, wherein the sensor is located between the inlet and the shut-off valve at a position such that the shut-off valve can be configured to the closed position prior to a portion of the gaseous feed, comprising the combustible component at a concentration over the specified concentration as measured by the sensor, flowing to the shut-off valve. ### Claim 4 (depends on 3) The system according to claim 3, wherein the first sensor is positioned proximal to a source of the gaseous feed. ### Claim 5 (depends on 2) The system according to claim 2, wherein the at least one combustion module is shut down to remove the combustion module as a potential ignition source upon measurement of a concentration of the combustible component in the flow of the gaseous feed over the specified concentration by the sensor and/or detection of flame by the flame detector. ### Claim 6 (depends on 2) The system according to claim 2, further comprising a combustion module flame arrestor located proximal each of the at least one combustion modules. ### Claim 7 (depends on 2) The system according to claim 2 wherein the flame arrestor comprises a crimped metal ribbon flame arrestor element. ### Claim 8 (depends on 7) The system according to claim 7, wherein the crimped metal ribbon flame arrestor element has an expansion ratio greater than 1. ### Claim 9 (depends on 7) The system according to claim 7, wherein the crimped metal ribbon flame arrestor element comprises a path length of from 10 mm to 250 mm. ### Claim 10 (depends on 2) The system according to claim 2, further comprising a first source of fresh air and a first fresh air valve for controlling flow of the first source of fresh air into the ducting system, wherein the first fresh air valve is operatively associated with the shut-off valve such that when the shut-off valve is configured to the closed position, the first fresh air valve is in an open position to allow flow of fresh air into the system for diluting the concentration of the combustible component. ### Claim 11 (depends on 2) The system according to claim 2, wherein at least one fire retardant injection point is positioned upstream of the shut-off valve and at least one fire retardant injection point is positioned downstream of the shut-off valve. ### Claim 12 (depends on 2) The system according to claim 2, further comprising one or more burst panels located upstream of the at least one combustion module and downstream of at least one fire retardant injection point. ### Claim 13 (depends on 2) The system according to claim 2, further comprising a second source of fresh air and a second fresh air valve for controlling flow of the second source of fresh air into the flow of the gaseous feed at a position upstream of the mixer. ### Claim 14 (depends on 13) The system according to claim 13, further comprising a pair of supplementary sensors to measure a concentration of the combustible component in the flow of the gaseous feed, wherein the pair supplementary sensors comprise one supplementary sensor positioned upstream of the mixer and another supplementary sensor positioned downstream of the mixer and wherein the pair of supplementary sensors are operatively associated with the second fresh air valve and the supplementary gaseous feed valve for controlling the concentration of the combustible component in the flow of the gaseous feed leaving the mixer. ### Claim 15 (depends on 2) The system according to claim 2, further comprising a ventilation air filter for filtering coal dust from the ventilation air. ### Claim 16 (depends on 15) The system according to claim 15, wherein the ventilation air filter is positioned upstream relative to the flame arrestor. ### Claim 17 A ducting system for conveying a flow of a gaseous feed of ventilation air derived from a coal mine comprising a combustible component from an inlet to at least one combustion module, the system comprising: a shut-off valve configurable to have an open position to allow the flow of the gaseous feed from the inlet to the at least one combustion module and a closed position to prevent the flow of the gaseous feed from the inlet to the at least one combustion module; a sensor to measure a concentration of the combustible component in the flow of the gaseous feed, the sensor located upstream of the shut-off valve; a flame detector located downstream of the shut-off valve; a flame arrestor located in a flow path of the gaseous feed upstream of the shut-off valve; a source of fire retardant and a fire retardant valve feeding one or more fire retardant injection points for controlling flow of the fire retardant into the ducting system, the one or more fire retardant injection points positioned between the flame arrestor and the at least one combustion module; a supplementary gaseous feed in fluid communication with a gas mixer for mixing the gaseous feed with the supplementary gaseous feed, the supplementary gaseous feed comprising a supplementary combustible component; a supplementary gaseous feed valve for controlling flow of supplementary gaseous feed into the flow of the gaseous feed downstream of the shut-off valve; a source of fresh air and a fresh air valve for controlling flow of the source of fresh air into the flow of the gaseous feed at a position upstream of the mixer; and a pair of supplementary sensors to measure a concentration of the combustible component in the flow of the gaseous feed, wherein the pair of supplementary sensors comprise one supplementary sensor positioned upstream of the mixer and another supplementary sensor positioned downstream of the mixer, wherein the shut-off valve is operatively associated with the sensor such that a measurement of a concentration of the combustible component in flow of the gaseous feed over a specified concentration by the sensor causes the shut-off valve to be configured to the closed position for preventing flow of a gaseous feed comprising a combustible mixture of the combustible component from reaching an ignition source, wherein the specified concentration is 1.25% methane as the combustible component, wherein the shut-off valve is operatively associated with the flame detector such that detection of flame by the flame detector causes the shut-off valve to be configured to the closed position for attenuating propagation of a flame toward the inlet, wherein the fire retardant valve is operatively associated with the flame detector such that detection of flame by the flame detector causes the fire retardant valve to open allowing the fire retardant to flow into the ducting system for attenuating the detected flame, and wherein the pair of supplementary sensors are operatively associated with the second fresh air valve and the supplementary gaseous feed valve for controlling the concentration of the combustible component in the flow of the gaseous feed leaving the mixer.