Ducting system

Patent metadata

Field	Value
Publication number	US-10758753-B2
Application number	US-201615764206-A
Country	US
Kind code	B2
Filing date	Oct 27, 2016
Priority date	Oct 30, 2015
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

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.

First claim

The invention claimed is:

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.

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.

3. 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.

4. The system according to claim 3 , wherein the first sensor is positioned proximal to a source of the gaseous feed.

5. 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.

6. The system according to claim 2 , further comprising a combustion module flame arrestor located proximal each of the at least one combustion modules.

7. The system according to claim 2 wherein the flame arrestor comprises a crimped metal ribbon flame arrestor element.

8. The system according to claim 7 , wherein the crimped metal ribbon flame arrestor element has an expansion ratio greater than 1.

9. 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.

10. 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.

11. 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.

12. 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.

13. 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.

14. 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.

15. The system according to claim 2 , further comprising a ventilation air filter for filtering coal dust from the ventilation air.

Assignees

• Commw Scient Ind Res Org

Inventors

• Su Shi
• Guo Hua
• Yu Xinxiang

Classifications

• F23G2208/10

  Preventing or abating fire or explosion, e.g. by purging · CPC title

• F23G2204/103

  gaseous or liquid fuel · CPC title

• E21F7/00

  Methods or devices for drawing- off gases with or without subsequent use of the gas for any purpose · CPC title

• F23G2209/141

  Explosive gases · CPC title

• A62C3/06 Primary

  of highly inflammable material, e.g. light metals, petroleum products · CPC title