Corky’s VAMCorky’s VAM--RABRAB

David Cork David Cork –– Technical Director Technical Director –– The Corky’s GroupThe Corky’s GroupPeter Bergin Peter Bergin –– Group Manager Business Improvement Group Manager Business Improvement –– Centennial CoalCentennial Coal117-Nov-11

AcknowledgementAcknowledgementAcknowledgement Acknowledgement • Corky’s are the designers, constructors and maintainers of the VAM RAB y g ,

demonstration plant to be developed at Mandalong

• Centennial Coal are the owners of the site on which the demonstration plant• Centennial Coal are the owners of the site on which the demonstration plant will operate.

• The project is jointly funded by NSW Department of Trade & Investment, Regional Infrastructure & Services through the Clean Coal Fund, which is administered by the Minister for Resources & Energy, Centennial Coal and y gy,Corky’s.

A i d h i d il fl h i f NSW• Any views expressed herein do not necessarily reflect the views of NSW DT&IRI&S or the NSW Government.

217-Nov-11

Indentifying the ProblemIndentifying the ProblemIndentifying the ProblemIndentifying the ProblemWorldwide ventilation air methane (VAM) emissions contributesWorldwide, ventilation air methane (VAM) emissions contributesto 17% of manmade greenhouse gas pollution (Mallett & Su, 2004).

These fugitive emissions are heading towards 10% of Australia’semissions by 2020. (Department of Climate Change, 2011)

With a carbon tax proposed to come into effect in July, 2012 inp p yAustralia, it has become a poignant issue to treat and reducethese emissions. The carbon tax in Australia is sufficiently high tol d d l i hi h ld h iclose some underground coal mines which would otherwise

have a long and profitable life.

317-Nov-11

Indentifying the ProblemIndentifying the ProblemIndentifying the ProblemIndentifying the ProblemIf Ventilation Air Methane (VAM) is such a large issue why has it notIf Ventilation Air Methane (VAM) is such a large issue why has it not been solved before:• Has been difficult to capture and use due to p

– Large airflows – (50 to 500 m3/s)– Low concentrations – 0.1 to 1.0%, typically 0.3 to 0.5%– Highly Variable methane concentrationHighly Variable methane concentration

• Technical restraints on technology– Safety – must manage system so there is no flame path between mine and reactor – Dust from coal mine reacts with bricks in fluxing reactor– Maintaining reactor temperature, VAM does not sustain oxidation easily, which is good for safety but poor for abatement – Temperature Control, occasionally the reactor can overheat – Management of heat/ energy recovery – there are large amounts of highly variable

waste heat

417-Nov-11

Application of TechnologyApplication of TechnologyApplication of TechnologyApplication of TechnologyLeading edge technologyOne size does not fit allChallenges to overcome:• Legislation• Safety levels• Technical issue – ongoing research• Efficiency of technology• Up scaling • Long term reliability and stability

617-Nov-11

Centennial CoalCentennial CoalCentennial CoalCentennial Coal• Proactive and supportive of VAM abatement

• Started VAM abatement discussions with Corky’s in early 2008

• Mandalong - host mine - located near Morisset, in the Newcastle Coalfield of NSW.

• VAM emission that are potentially abatable of 600 - 700 kt pa

717-Nov-11

Centennial MandalongCentennial MandalongCentennial MandalongCentennial Mandalong

817-Nov-11

Centennial MandalongCentennial MandalongCentennial MandalongCentennial MandalongVentilation Air Flow 300 m3/sVAM concentration 0.60 %

Methane flow 1.80 m3/s6 480 m3/h6,480 m /h

155,520 m3/day56,764,800 m3/y

37 147 t/y37,147 t/y

CH4 + 2O2 ⇒ CO2 + 2H2O

Global Warming Potential 21abatement GWP 20

abatement benefit 742,934 t/y CO2 equ

917-Nov-11

Corky’s TechnologyCorky’s TechnologyCorky s TechnologyCorky s TechnologyBased on Traditional Coke Battery Design y gPrinciples• 100 years plus of history• Ver large thermal mass• Very large thermal mass• Low pressure drop (open chequers)• Gas Gun fired as top-up fuel• Known brick and refractory methods• Known reversal patterns• Kno n performance ith et and d st Blast• Known performance with wet and dusty Blast

furnace gas• One must control Temperature

1017-Nov-11

Ventilation Air Methane Ventilation Air Methane R ti Aft BR ti Aft BRegenerative After Burner Regenerative After Burner VAMVAM--RABRABNov 09

Nov 10

1117-Nov-11

Project StageProject Stage Demonstration PlantDemonstration PlantProject Stage Project Stage –– Demonstration PlantDemonstration Plant

P f b i ti d f t tPre fabrication and safety systems testing at Carrington

1217-Nov-11

Regenerative HeatingRegenerative HeatingRegenerative Heating Regenerative Heating R d id fi i G id fi iRed side firing Green side firing

Air out at

VAM in at 25oC

85oC

1317-Nov-11

High Thermal MassHigh Thermal MassHigh Thermal MassHigh Thermal MassThe chequer height, hence thermal mass, is approximately 3 times what is required for stable methane concentration operation.

Tall structure leads to low fraction of RAB beingTall structure leads to low fraction of RAB being filled with VAM. The VAM filled portion is between 29 to 34%.

Very slow rise in pressure resulting from a methanespike event due to heat being absorbed by the Chequers low gas turbulence and by the lowChequers, low gas turbulence and by the low VAM fraction of total volume.

No fire observed in duct when operating above LEL

Air filled volumeVAM filled volume

1417-Nov-11

Energy BalanceEnergy Balance3.0

energy per 10 m3/s MWt

Energy BalanceEnergy Balance2 0

2.5

t

energy per 10 m3/s, MWtsupplementary energy, MWtexcess energy, MWt

1.5

2.0

rgy

MW

t gy,electricity, MWe (gross)

0 5

1.0Ener

For example:

0.0

0.5

0 1% 0 3% 0 5% 0 7% 0 9%

300m3/s at 0.6% methaneIs 66.6MWt heat input with 37 2MW potentially recoverable0.1% 0.3% 0.5% 0.7% 0.9%

Methane Content37.2MWt potentially recoverable

1517-Nov-11

Why Potentially Recoverable?Why Potentially Recoverable?3.0

energy per 10 m3/s MWt

Why Potentially Recoverable?Why Potentially Recoverable?2 0

2.5

t

energy per 10 m3/s, MWtsupplementary energy, MWtexcess energy, MWt

Typical methane distribution

1.5

2.0

rgy

MW

t gy,electricity, MWe (gross)

VAM does not exist as a single point:

0 5

1.0Ener VAM does not exist as a single point:

• Graph shows average of 0.5% and std 0.13%

• 16% of time (methane below 0 23%) and

0.0

0.5

0 1% 0 3% 0 5% 0 7% 0 9%

• 16% of time (methane below 0.23%) and you will need to add heat

• 16% of time (methane above 0.77%) and ill d t d h t0.1% 0.3% 0.5% 0.7% 0.9%

Methane Contentyou will need to dump heat

• Confident to recovery only 68% of heat even with high thermal mass

1617-Nov-11

Two Heat Recovery OptionsTwo Heat Recovery OptionsTwo Heat Recovery OptionsTwo Heat Recovery OptionsLow grade heat recovery using y gheat transfer oil at low pressure. Bigger heat High grade heat

recovery using exchanger and more refractory brick at top but

recovery using steam at high pressure. Smaller heat exchanger cheaper to operate

and maintain.

heat exchanger but more expensive to operate andoperate and maintain.

Honeycomb brick at base

1717-Nov-11

Thermal Energy AvailableThermal Energy AvailableThermal Energy AvailableThermal Energy AvailableAverage Methane % High Grade Heat

MWt at 400oCLower Grade Heat

MWt at 200oC

0 3% 1 9 2 70.3% 1.9 2.7

0.4% 11.0 15.4

0.5% 18.2 25.4

0.6% 25.3 35.3

0.7% 32.4 45.3

0.8% 39.7 55.5

0.9% 46.7 65.3

A i VAM fl f 300 3/Assuming average VAM flow of 300m3/s

1817-Nov-11

Connection to MineConnection to Mine -- ScopeScopeConnection to Mine Connection to Mine ScopeScopeProposed Solution• Passive safety design where combustion is in the chequersy g q• Have five independent layers of protection• Three layers to stop VAM spike reaching RAB• Two layers to stop deflagration flashback reaching mine fanTwo layers to stop deflagration flashback reaching mine fan• Solution is scalable to full commercial implementation• Independent layers mutually supportive

eg barriers work in both directioneg. barriers work in both directioneg. dilution door also act as pressure relief

ibl

Bypass

Frangible Pressure Relief System

Bypass System

Dilution System

1917-Nov-11

Connection to MineConnection to Mine CHCH measurementmeasurementConnection to Mine Connection to Mine –– CHCH44 measurementmeasurementMineMine

ventilation fan

10 m3/s along 4 m duct of CSA 1.5m2ILP 2 and 5 10 m /s along 4 m duct of CSA 1.5mVelocity along duct 6.6 m/s10 m3/s along 10 m duct of CSA 3.0m2

Velocity along duct 3.3 m/s

ILP 2 and 5 O2 sil 2

ILP 1 CH4 sil 2

y g /Warning time: 0.6+3.0 = 3.6 seconds

ILP 2 CH4 sil 2

ILP 4 CH4 sil 2

310 m3/s up a 240 m shaft of diameter 5.5mVelocity up shaft 13.0 m/sWarning time 18.4 seconds

2017-Nov-11

Connection to MineConnection to Mine Safety SystemsSafety SystemsConnection to Mine Connection to Mine –– Safety SystemsSafety SystemsILP 1

un mitigated risk

ILP 1

ILP 2 LOP Corky’s Others

ILP 3

ILP 4

ILP1 SIL rated bypass no

ILP2 SIL rate dilution doors

noILP 4

ILP 5

doors

ILP3 Passive design no flames at base

no

ILP 6 other systems like flame arrestors, fire fighting

foams, sprinklers, etcILP4 SIL rated isolation no

ILP 5 SIL rated frangible design

no

Fully mitigated risk

design

2117-Nov-11

Modular DesignModular DesignModular DesignModular Design

F RAB ll h k RAB kFour RAB cells together to make a RAB pack. Each RAB pack has two reversal patterns. The

pilot RAB is a full scale RAB cell.

2217-Nov-11

How is Four Pack Different to How is Four Pack Different to D t ti Pl tD t ti Pl tDemonstration PlantsDemonstration PlantsA four pack has:p

• Lower cost per volume of VAM abated.

• Less heat lost due to reduced surface area per reaction volume. Therefore will work better at 0.3%.

• More surface area in bottom half and this will result lower exhaust temperature. Therefore it will work better at 0.3%

• More refractory mass per reaction volume. Therefore more steady operation.p

• And is designed for low grade heat recovery (fitting HE is optional)

2317-Nov-11

Large Scale RAB Installation Large Scale RAB Installation 160 to 200 m160 to 200 m33/s/s -- 4 four packs4 four packs160 to 200 m160 to 200 m /s /s -- 4 four packs4 four packs240 to 300 m240 to 300 m33/s /s -- 6 four packs6 four packsF i

10 di

Footprint 66 m by 57 m

24 m2/m3 of VAM10 m radius hemisphere

exclusion zoneVentilation

Frangible duct

Dilution doors

Ventilation Fans

100m3/s each

duct

Barriers

doors

Bypass vents

VAM RAB tower identical between applications

2417-Nov-11

Large Scale RAB Large Scale RAB --4 four packs4 four packsgg pp

Dilution doors

Dilution doors

Dilution doors

Vent Louvers

Frangible

Frangible duct

doors duct Frangible duct

Isolation Louvers/ curtains

2517-Nov-11

Large Scale RAB Large Scale RAB –– 12 four packs12 four packsgg ppFootprint Ventilation

15 m radius hemisphere

l i

112 m by 112 m26 m2/m3 of VAM

Fans

240m3/s eachexclusion zone

Bypass

BarriersDilution

Bypass vents

Dilution doors

Frangibleduct

VAM RAB tower identical between applications

2617-Nov-11

pp

QuestionsQuestionsQuestionsQuestions

2717-Nov-11