Classifications

• • G—PHYSICS
  • G08—SIGNALLING
  • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
  • G08B17/00—Fire alarms; Alarms responsive to explosion
  • G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
  • G08B17/117—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means by using a detection device for specific gases, e.g. combustion products, produced by the fire

Definitions

• the invention relates to a method for the detection of smoldering fires in containers containing lignite dust, with the aid of which certain gases which form in the lignite dust and possibly escape therefrom are measured with a suitable detector and used as "indicator gases" for early smoldering fire detection can.
• H 2 and CH * only appear when a smoldering fire has occurred in the bed.
• This detection of a smoldering fire by detection of H 4 and CH 4 is, in addition to the previous early detection via CO, a further developed method for the detection of smoldering fires in lignite dust.
• a limit concentration is given for H 2 and CH. not absolutely necessary, since these gases are specific for the presence of a smoldering fire.
• the measurement of CH 4 is particularly suitable for the detection of smoldering fires.
• a detector for detecting the gases in question is attached to the container containing lignite dust in such a way that it either probes into the emptying nozzle of the loading device. engages container or into the interior above the emptying nozzle, the probe being able to reach both in the region of the dumping height and in the gas space above the dumping height.
• a plurality of such probes can also be provided spaced apart from one another and / or distributed in the circumferential direction over the length of the container.
• the probes can either have detectors themselves or can be provided with connections which feed a mostly small amount of gas required for the measurement to a suitable device, for example a gas chromatograph or other gas analyzer.
• a suitable device for example a gas chromatograph or other gas analyzer.
• the method according to the invention was first tested in the laboratory.
• smoldering fires were generated in a dust bed by heating the bed and introducing air.
• the laboratory ässige method for target the composition of the gebil ⁇ by a smoldering brown coal dust Deten gases had to be compared with isti ⁇ gas which then forms ge # is when there is no smoldering is present.
• the temperature in the bed was measured using thermocouples. After the above-mentioned temperatures had been reached in the bed, preheated air was introduced into the BK dust bed over a period of approximately 7.5 hours. The air flow rate was approximately 0.1 l / min.
• the composition of the gas leaving the test apparatus was determined by gas chromatography with respect to H 2 , CH. , CO and CO- determined.
• FIG. 1 The results of the tests are shown in a diagram in FIG. 1.
• the representation is not to scale, in fact with regard to the relatively low values for hydrogen and methane.
• the diagram shows the proportions of the individual gas components H 2 , CH., CO and C0 2 in volume percent (vol.%) Depending on the test temperature.
• a lignite dust bunker 1 narrows in its lower part to form a funnel 2 which opens into an outlet element 3.
• This outlet member 3 consists in particular of a cellular wheel 4 with drive 5 and a bellows 6 for adaptation to different customers.
• the dust bunker 1 at the level of its funnel 2 has a ring line 7 for supplying compressed air, so that the bed inside the dust bunker can be loosened if necessary.
• a CH 4 -IR gas analyzer engages with a probe 8 in the emptying neck of the container.
• three identical probes 9 are attached over the axial length of the container at almost the same distance and possibly distributed in the circumferential direction, the probes projecting both into the area of the dust bed 10 and into the gas space 11 above the bed.
• probes are also connected to a CH 4 ⁇ IR gas analyzer. Dust filters (not shown) are installed between the probe 8 or the probes 9 and the CH ⁇ -IR gas analyzers to protect the measuring devices.
• Dust filters (not shown) are installed between the probe 8 or the probes 9 and the CH ⁇ -IR gas analyzers to protect the measuring devices.
• In the course of the individual experiments of CH determined using the probe 9 was 4 ⁇ basic value in the bunker 5-33 measured through the probe 8 ppm CH 4 -Grundwert during the emptying of the hopper is about 10 ppm.

Landscapes

• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Sampling And Sample Adjustment (AREA)
• Investigating Or Analyzing Materials Using Thermal Means (AREA)
• Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
• Investigating Or Analysing Materials By Optical Means (AREA)
• Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
• Processing Of Solid Wastes (AREA)
• Solid Fuels And Fuel-Associated Substances (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6136361

Family Applications (1)

Country Status (8)

Cited By (1)

Families Citing this family (4)

Citations (7)

• 1981
  • 1981-07-08 DE DE3126864A patent/DE3126864C2/de not_active Expired
• 1982
  • 1982-06-04 CS CS824164A patent/CS245771B2/cs unknown
  • 1982-07-06 DD DD82241440A patent/DD207438A1/de not_active IP Right Cessation
  • 1982-07-07 WO PCT/DE1982/000142 patent/WO1983000247A1/de not_active Ceased
  • 1982-07-07 AU AU86886/82A patent/AU557814B2/en not_active Ceased
  • 1982-07-07 AT AT82106076T patent/ATE16429T1/de not_active IP Right Cessation
  • 1982-07-07 CA CA000406836A patent/CA1187718A/en not_active Expired
  • 1982-07-07 EP EP82902156A patent/EP0082867A1/de active Pending
  • 1982-07-07 EP EP82106076A patent/EP0069393B1/de not_active Expired
  • 1982-07-07 DE DE8282106076T patent/DE3267275D1/de not_active Expired

Patent Citations (7)

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