Fracking and Coal Bed Methane

[Wheldale]

The is a link here to the UK's governments fact sheet on fracking. A bit of a hot potato but will it help us with our energy supplies?

www.gov.uk/government/uploads/system/uploads/attachment_data/file/265972/Developing_Onshore_Shale_Gas_and_Oil__Facts_about_Fracking_131213.pdf

Heres a link to a large paper about coal bed methane. Another way to extract gas, this one from coal seams.

www.og.decc.gov.uk/UKpromote/onshore_paper/Promote_UK_CBM.pdf

[Minutor]

Thanks for the links

There are also some good links to submissions made by the Geological Society and other Institutions on shale gas here:

www.geolsoc.org.uk/shalegas

Will it work? We will only know after the exploration and trial wells have been completed but it is not without significant challenges.

With shale gas the main challenges seem to be the problem of overcoming low permeability by fracking and sourcing and managing the water required to do it. For Coal Seam Gas it is the removal of water and recycling / disposal of this water. A company I am involved with at present has a small interest in a CSG project in Australia, it is going to take a year to de-water the coal seam!

[Wheldale]

Heres a link about water used in fracking, its about the flow back water, this is water that has been used in a fracking well and been pumped out.

www.environment-agency.gov.uk/static/documents/Business/6th_Dec_-_Shale_gas_-_North_West_-_Monitoring_of_flowback_water_-_update_(3).pdf

[tygwyn]

I have been racking my brain,well what`s left anyway,How do you de-water a Coal Seam,

I`ve worked in some really wet Collieries in South Wales,mainly in the Rhondda No.2 seam,with a porous sandstone roof,but the water only came through the roof after the coal was fired,which was dry and dusty,hence why we fired the face end of shift to damp down for the following day.

[Wheldale]

I'm thinking that they just pump the area dry. Maybe some area's are better than others?

[tygwyn]

Apr 1, 2014 15:54:16 GMT -5 Wheldale said:

I'm thinking that they just pump the area dry. Maybe some area's are better than others?

If there are old workings in the area,but its only the workings that get pumped out,
Its de-watering the seam i cannot get my head around,

If water came through the coal,then that would have been obvious in the Gleision with 650,000 gallons of water behind the pillar,and that only being a few yards,

But maybe Coking coal works different,i`ve never worked that. only Anthracite and Dry Steam and the inbetween`s.

[Wheldale]

I think for coal bed methane in the UK they will be going for deeper unworked seams. I don't know Tygwyn if the places were you worked were near to the surface or aquifier but the examples that ive seen are for fairly deep seams, 1000m + so will be well under the aquifiers. From my understanding these seams will contain water but once pumped dry they will be dry for a long time as there are no other feeds of water to them. Were as the shallow seams will have quite a lot of surface water draining down to the workings etc.

Once the seams are pumped dry this apparently releases pressure on the gas in the coal seams and it then flows to the surface via a borehole, much the same as how methane drainage works on a coal face.

[tygwyn]

Yes,all the Smallmines i worked at were outcrop levels and drifts,bar one,that had around 100yds of a cross measure to reach the coal,
I have no idea of underground conditions up North,except one of the boy`s we know is working at Kellingley with contractors doing salvage,the Devil`s Arsehole he calls it,as its damn hot down there compared to Unity were he last worked,i know one of the boy`s on the Welsh Forum worked for years around the Warwickshire coalfield and he said they were dry compared to South Wales.

The Llwynypia/Glamorgan Colliery was pumping 6-8 tons of water per ton of coal daily,that`s a lot of water.