UNCONVENTIONAL
FRACKING of GAS FROM SHALE
SUMMARY OF THIS LECTURE BELOW - 2012
(Shows Fracturing of shale for gas in the US)
(Shale oil is not known to be found in the Kimberley)
Shale is sedimentary rock
Shale oil is an unconventional oil produced
from oil shale rock fragments by pyrolysis, hydrogenation, or
thermal dissolution. These processes convert the organic matter within the rock
(kerogen) into synthetic oil and gas. ... The
refined products can be used for the same purposes as those derived from
crude oil.
Shale oil is a substitute for conventional crude
oil; however, extracting shale oil from oil shale is
more costly than the production of conventional crude
oil both financially and in terms of its environmental impact.
Deposits of oil shale occur around the world, including major
deposits in the United States.
Environmental
impact of the oil shale industry includes
the consideration of issues such as land use, waste management, and water and air pollution caused by the extraction and
processing of oil shale. Surface mining of oil shale
deposits causes the usual
environmental impacts of open-pit mining. In addition, the combustion and thermal
processing generate waste
material, which must be disposed of, and harmful atmospheric emissions,
including carbon dioxide, a major greenhouse gas. Experimental in-situ conversion processes
and carbon
capture and storage technologies
may reduce some of these concerns in future, but may raise others, such as the
pollution of groundwater.[1][2]
What is the difference
between unconventional and conventional gas?
Because they are
easier and less expensive to produce, conventional (one Well /one path) oil and gas were
the first targets of industry activity using low pressure ... By
contrast, unconventional (multi Wells and path) resources
are trapped in reservoirs with low permeability, meaning little to no ability
for the oil or natural gas to flow through the rock and into a
wellbore. It requires 4 technologies to
retrieve the gas using high pressure.
The layer of shale might be 1500 metres down to the shale
layer which might only be 30 metres thick.
The drilling then goes horizontally to follow the shale in either
direction. The lateral is at least as
long at the vertical and often longer.
The longest lateral drilling is about 3000 metres. The casing is about 6 inches diameter.
Fluid is used to fracture the rock. HYDRAULIC means FLUID.
You need an incredible amount of pressure to force 6
million gallons of fluid through the 6 inch casing. This creates friction by the water flow so
chemical is added to reduce the friction to make it ‘slick water’ which flows
more easily.
Showing drilling laterally and then fracturing left and right
vertically and horizontally. The spacing
in only a foot or two between the yellow fracture lines.
Fractured using water, chemical and sand
Convention gas uses 10’s of 1000’s of gallons of fracturing
fluid but with unconventional fracking it uses millions of gallons of fluid.
SHALE GAS MEANS YOU DRILL EVERYWHERE RIGHT ALONG AND ACROSS
THE LAYER OF SHALE
· FRACKING
HAS BEEN DONE SINCE 1947 BUT ONLY ONE PART OF IT – MODERN FRACKING IS JUST
RECENT TECHNOLOGY
· THE FIRST
HORIZONTAL DRILLING WAS 1991
· SLICK WATER
1996
· MULTI
SLICK WATER FRACTURING 2002
· MULTI
WELLS AND CLUSTER DRILLING 2007
SUBSEQUENT ISSUES WERE NOT PLANNED FOR:
· REGULATIONS
WERE NOT READY
· THE REGULATORS
WEREN’T READY
· WASTE FACILITIES
WERE NOT IN PLACE
· NOT
ENOUGH TIME TO CONSIDER THE IMPACTS ON THE ENVIRONMENT AND OUR OWN HEALTH.
· A DATA
BASE NEEDED TO BE DONE OF WHERE THE WELLS WERE BEING DRILLED
· A DATA
BASE TO DOCUMENT VIOLATIONS
· A DATA
BASE FOR WASTE DISPOSAL
· WHAT IS
THE IMPACT OF 100,000 UNCONVENTIONAL SHALE GAS
FREQUENCY OF ACCIDENTS OF FAULTY WELLS (SAID TO BE ‘RARE’)
· GAS
MIGRATION OUTSIDE THE CASING OF THE WELL CAN COME IN CONTACT WITH DRINKING
WATER IN THE LAYERS ABOVE THE SHALE – ‘METHANE’ CONTAMINATION OF WATER WELLS
ETC. METHANE ALSO MIGRATES INTO THE
ATMOSPHERE WHERE IT BECOMES A POTENT GREENHOUSE GAS.
· METHANE
GAS WAS FOUND BUBBLING UP IN TROUT RIVERS COMING FROM OVER 1 KILOMETRE AWAY.
· THE METHANE
GAS AND OTHER HYDROCARBONS DON’T JUST BUBBLE UP IN RIVERS – IT BUBBLES UP ANY
PLACE AND YOU WON’T KNOW. YOU CAN’T SMELL
IT. YOU CAN MEASURE IT IN THE ATMOSPHERE
AND IT WAS FOUND TO BE A LOT.
WHY DO WELLS FAIL?
· THE
CASING CAN FAIL
· THE
CONCRETE SURROUNDING THE CASING CAN FAIL
· NEW WELLS
HAVE A FAILURE RATE OF 1 OUT OF 20
· OFSHORE: THE
OLDER THE WELLS THE MORE LEAKAGE UP TO 1 OUT OF 2. EVENTUALLY ALL WELLS LOOSE THEIR INTEGRITY.
· ONSHORE 4
- 5% LEAK – for 100,000 Wells drilled, that’s 5000 LEAKING WELLS WHICH IS
SIGNIFICANT.
· CONTAMINATION
OF DRINKING WATER BY METHANE, HAUDRAULIC FLUIDS, HYDROCARBONS
·
A typical large
Frack job (16 Wells on one pad of 1 to 2 square miles underneath the surface)
requires
o 417 million gallons of water,
o 78,000 tons of sand
o 8 million gallons of fracking chemicals
o 500 frack intervals
o 10,000 foot laterals
o 40,000 HP for fracking pumps
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