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CASE STUDY ON DEALING FIRE AT JAWAHARKHANI MINE IN SCCL INDIA. General Information Mine Started on : 1.7.1982 Extractable reserves : 17.5 MT Mine leasehold area : 4.6 Sq. Km Workable seams ==> 1. Queen Seam
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CASE STUDY ON DEALING FIRE AT JAWAHARKHANI MINE IN SCCL INDIA
General Information • Mine Started on : 1.7.1982 • Extractable reserves : 17.5 MT • Mine leasehold area : 4.6 Sq. Km • Workable seams ==> 1. Queen Seam (thickness 16m - 22m) 2.King Seam (thickness 1.6m to 2.3m) • The partition between two seams - 65 mtrs sandstone
General Information: • The King Seam was extracted in 1940’S • Present working seam : Queen Seam (in two sections) • Thickness of Queen Seam : 16m to 22m • Working Section : Top & Bottom (3m each) with a partition of 3m-5m • Seam Gradient : I in 5.8
DESCRIPTION THICKNESS (M) BORE HOLE NO. Q/179 SECTION OF QUEEN SEAM C S S 4.10 G S S 1.05 SHALY COAL 2.22 5 - 7m 0.48 COAL 0.23 0.43 SHALY COAL 2.42 3.0m WORKING SECTION OF TOP GREY SHALE 0.31 2.90 SHALY COAL QUEEN SEAM 16 - 22 m 0.16 C S S 3 - 5m SHALY COAL 1.02 GREY SHALE 0.62 SHALY COAL 3.65 3.0m WORKING SECTION OF BOTTOM COAL 2.40 G S S 5.85
HOW WAS THE PROBLEM FOUND? • On 28.3.2005 at 1.20 PM Assistant Manager during his inspection detected traces of CO in 31 Rise Return Airway. • One team of officials inspected 51 level bottom section traveled through the staple raise ( Ventilation Door Wall) and then inspected 51 Level Top Section. • The team reported that they could not find any CO however they could not venture into 51 level junction and 31 rise/ 51 level due to roof falls.
SMELL OBSERVED AREA OF SPONTANEOUS HEATING x 46 L BUNKERS Intake Airway N Return Airway 47 L CO 900 PPM 48 L ‘0’XCUT EFFECTED AREA ‘1’XCUT 49 L GOAF OF LWP 3 Top sec. Sealed on 26.12.1994 Bot. Sec. Sealed on 7.9.2003 SP 31 D I P 50 L 30 D I P 26 D I P 52 L AS ON 28.3.2005 54 L 55 L SP GOAF OF LWP 7 Top Sec. Sealed on 5.8.1997 Bot. Sec. Sealed on 26.2.2005
VENTILATION IN 'X' DRIFTS LOOSE COAL 31 DIP 30 DIP INTAKE RETURN TOP SECTION BOT SEC 51 L TOP. SEC TG SP 51 L BOT. SEC TG GALLERY
900 ppm of CO was observed at 31dip of 47level. • Agent, Manager and other senior officials of the mine inspected the site. • It was suspected that the seat of fire is likely at 31dip between 48L & 49L of Top section of Queen Seam.
The mine officials decided to isolate the area by constructing 4 stoppings at: 1. 31dip of 51 level in top section ( Door Wall), 2. 48 LN X cut of 30dip, 3. 49LN X cut of 30dip, 4. 31dip of 47LN. • However only three stoppings could be constructed before summoning the rescue services. The 31 dip of 47 level stopping could not be completed due to presence of CO more than 1000 PPM. • Due to inability of constructing the return stopping at 31 Dip of 47 Level by mine workers Rescue Teams were summoned.
STOPPINGS CONSTRUCTED AROUND THE FIRE AREA Constructed by rescue teams LOOSE COAL INTAKE 31 DIP 30 DIP 3 AS ON 30.3.2005 TOP SECTION BOT SEC 2 51 L TOP. SEC TG 1 SP 51 L BOT. SEC TG GALLERY
Director of Mines Safety ,& Senior officers of the company were informed. • Emergency organization was put into action by calling Rescue, Medical & other essential services.
Rescue Teams inspected 31 Dip/47 Level upto 48 Level. • In 31 Dip below 48 Level inspection could not be done due to presence of roof fall. • Existing stopping in 48 Level South X cut /31 Dip was found to be collapsed and the X cut was also found to be filled up with fallen coal.
Dense smoke was observed emanating from 31 Dip below 48 Level. • There was no smoke at 48 Level X- Cut/31 Dip. • Based on the inspection of the rescue teams it was then suspected that the seat of fire is either at X cross cut in 49 Level/31 Dip or inside the Goaf of Long wall Panel No. 3
Visibility was limited, there was heavy smoke & CO was detected to be above 2, 000 PPM exceeding the limits of the hand held gas detectors. • Rescue teams then constructed the return airway stopping at 31 Dip/ 47 Level which was completed by 8: 30 A.M on 29.03.05. • The total combustibles also exceeded 3% during the final stages of construction of the stopping.
The presence of combustibles was attributed to the fact that the access of air to the area under fire has been cut-off by construction of the three stopping while the return airway being kept open. • The presence of combustibles also indicates active distillation of coal.
Yet at the out-bye of the stopping CO was found to be more than 1000 PPM. • This was attributed to access of air through bottom & sides of the coal pillar and large pressure differences. • The stoppings were further strengthened and plastered with cement.
Rescue Teams then inspected all galleries starting from 47 Level to 52 level from 35 dip to 30 Dip. • In 52 Level bottom gate road of goaved out Longwall Panel No. 3 was found to be sagging and the area near the Fire Seal was partially collapsed and height was just 3 Feet. • Further in 51 level,& 50 Level at many places the partition between the top and bottom sections were found to be collapsed.
Based on this inspection report of rescue teams it was decided to isolate a wider area encompassing the area where the partitions have collapsed allowing access of air into the goaved out area of Longwall Panel No.3. • Isolating this area required 16 stoppings to be constructed. • However this job could not be taken up as the total combustibles inside the sealed-off area increased to more than 6% by 12: 30 PM on 29.03.05.
The mine was laid-off from 2nd shift of 29.03.05. Only the essential manpower required for recovery operations were engaged. • The 4 temporary stoppings were strengthened by 1.0 m thick sand bag stoppings by Rescue Personnel. • The atmosphere inside the stoppings was regularly monitored every hour.
SEALS 48 L 30 DIP 51L TG 31 DIP FIRE SEALS BOT TG PRO. BHs 49 L SP TOP SECTION GALLERIES GOAF OF LWP 3 50 L 55L MG BOT MG 52 L
Air samples every four hours shall be collected and analyzed, spot air samples shall be recorded hourly at the main return with due safety precautions. • These instructions shall be recorded in the instructions register at the control room and all officers, supervisors concerned shall be made aware.
31 DIP LOOSE COAL PRO. BHs 30 DIP TOP SECTION BOT SEC BHs POSITION IN 'X' DRIFTS 51 L TOP. SEC TG 51 L BOT. SEC TG GALLERY
BHs DRILLED IN ‘X’ DRIFTS 48L X DRIFT BHs 30 DIP 49L X DRIFT 31 DIP
CO2 GAS FILLING THROUGH BH No 1A 48L X DRIFT BHs 30 DIP AS ON 7.4.2005 1A 49L X DRIFT 31 DIP
CO2 GAS FILLING THROUGH BH No 1B 48L X DRIFT BHs 30 DIP 1B AS ON 10.4.2005 1A 49L X DRIFT 31 DIP
CO2 GAS FILLING THROUGH BH No 2A 48L X DRIFT BHs 4 30 DIP 1B AS ON 10.4.2005 1A 3B 5A 49L X DRIFT 31 DIP 2A
CEMENT INJECTION CEMENT SLURRY INJECTION THROUGH BH No. 1A 48L X DRIFT PUMP BHs CEMENT SLURRY 4 30 DIP 1B AS ON 10.4.2005 1A 3B 5A 49L X DRIFT 31 DIP 2A
CEMENT INJECTION CO2 GAS FILLING THROUGH BH No 3B 48L X DRIFT BHs 4 30 DIP 1B 1A 3B 5A 49L X DRIFT 31 DIP 2A
CEMENT INJECTION CEMENT SLURRY INJECTION 48L X DRIFT BHs 4 30 DIP 1B 1A 3B 5A 49L X DRIFT 31 DIP 2A
CEMENT INJECTION FIRE AREA FILLED WITH CEMENT SLURRY 48L X DRIFT BHs 4 30 DIP 1B AS ON 22.4.2005 1A 3B 5A 49L X DRIFT 31 DIP 2A
Surface fan was started and operated for 1 hr at 9.30PM with doors open. • In third shift rescue teams were sent to under ground again after stopping the surface fan. • The rescue team collected air samples and inspected the 26dip area in bottom section where stoppings were proposed and returned to surface by 6.10am on 23.4.2005.
LOOSE COAL On 23.4.2005 in first shift rescue teams went to under ground extended sampling pipe at 51LN of 30dip bottom section fire seal upto 46L through 30rise. 31 DIP 30 DIP AS ON 30.3.2005 BOT SEC TOP SECTION 51 L TOP. SEC TG SP Sampling pipe 51 L BOT. SEC TG GALLERY
FOAM TYPE STOPPING Construction of 16Nos of foam type stoppings was started in 2nd shift of 23.4.2005 and completed by 4.30PM on 24.4.2005WITH IN THREE SHIFTS
FOAM TYPE STOPPING CONSTRUCTION VENT SEAL WITH FOAM FOAM TYPE STOPPING
POSITION OF VENT SEALS BUNKERS N VENT SEAL 47 L BOT SEC TOP SEC 48 L 30 D I P ‘0’XCUT ‘1’XCUT 49 L GOAF OF LWP 3 Top sec. Sealed on 26.12.1994 Bot. Sec. Sealed on 7.9.2003 SP 31 D I P 50 L 26 D I P 52 L AS ON 24.4.2005 54 L 55 L SP GOAF OF LWP 7 Top Sec. Sealed on 5.8.1997 Bot. Sec. Sealed on 26.2.2005
POSITION OF FINAL STOPPINGS VENT SEAL BUNKERS N STOPPINGS 47 L AREA ISOLATED IN BOT. SEC AREA ISOLATED IN TOP. SEC 48 L 30 D I P ‘0’XCUT ‘1’XCUT 49 L GOAF OF LWP 3 Top sec. Sealed on 26.12.1994 Bot. Sec. Sealed on 7.9.2003 SP 31 D I P 50 L 26 D I P 52 L AS ON 26.4.2005 54 L 55 L SP GOAF OF LWP 7 Top Sec. Sealed on 5.8.1997 Bot. Sec. Sealed on 26.2.2005
AS PER THE ADVICE OF DDMS THE SURFACE AREA OVER THE LW PANEL No. 3 NEAR THE BARRIER HAS BEEN FILLED WITH OB AND DOZED FOR COMPACTNESS TO ARREST BREATHING OF AIR FROM SURFACE LONGWALL PANEL No. 3 SUBSIDENCE AREA FILLED WITH OB