Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1936-10-31
lcontIued from - onel

covered by acidlzing, over and above the
expected recovery.
II Is safe to assume that the ecOnomi-
cal lives Of these wells have been ex-
tended from to years and that the
Increased recovery from this group oi
wells Will be approximately SO,000 bar
rels. However, treatment OF additional
wells and Entertainments probably Will
increase this figure materially.
Early and intelligent use OF acids Is
indicated as one OF the best means OF
securing the greatest ultimate recovery.
The logic back OF this IL easily under
stood When a well Is drilled In, all
producig horizons viii be under more
nearly the same pressure, allowing FOR
Is operated. most OF the oil and gas
viii be removed from the permeaule
sections. II the acldixing program is
delayed. the acid viii lend TO penetrate
these more permeahle sections because
the reservoir pressure viii be less and
the resistance to flow also less. BY early
acidizing, Il is possible to more eff
GENTLY direct the acid into all parts Of
the pay and the penetration will be more
GAs/OIL RATIO
The lowering OF gas/oil ratio is also
problem OF extreme Importance to
engineers wherever oil Is produced. be-
cause this Is really the problem Of Ill
innate recovery expressed In different
terms. Everyone now realizes that the
energy OF the reservoir Is the principal
moving oil through the formation TO the
well. Its conservation WILL therefore,
result In greater financial return to the
operator.
Many mechanical methods OF cOntroll-
ing excessive gas/or ratios have been
developed; some at tremendous cost.
1t has been found that the use Of ehemi-
calls will materially aid ia reducing
the production OF the oil-bearing for
nation.
The treatment for gas /oil ratio control
usually takes a different form than the
tS fom tS Il e 6oT
lion without altering the conditions Of
the gas horizon. Testimony as presented
before the OH Conservation Commission
out that such treatments DO produce
results. There is was definitely stated
that the production on a ceratin we'll
was trebled without affecting the gas
potential In any major way. AS a result
the well produced its allowable follow
ing treatment with a greatly improved
gas Loii ratio. Other wells treated IN
Hobbs have shown a decline In gas FOIL
ratio following treatment from 1900
cubic feet per barrel 20 ! 800 feet and
from 5000 or 6, feet TO 1900 feet
WATER /OIL RATIO
Another factor In the economics OF oil
produced with the oil and must be
lifted TO the surface to be separated
from the oil. This becomes even more
important u the water has to be dis.
posed Of In a nIaner to avoid surface
The lifting cost for a barrel Of water
is at least as much as for a barrel Of
the Well can be made TO produce more
oil per barrel OF water viii automatically
Increase the revenue from the well and
At the same time lower the lifting cost
per barrel.
BY Introducing acid into that part Of
lie formation which does not make water
{ Is possible 10 lower the water /OTf
alto by making the oil zone more pro-
iuetive. Water Is usually found in the
'ottom OF the producing section and by
certain chemicals known TO
he trade as Blankets, Jelly Seals, and
cid opposite the OIL producing zone and
hus Keep the solvents from entering
he water horizon.
The accompanying graph clearly shows
treatment OF a we'll producing consid.
rable percentages Of water when the
II and water are produced from distinct
orizons In the formation.
Graph b is a representative treatment
asuH made from production data on a
ell eight years old producing from the
swego lime OF Oklahoma, showing that
lis Wen was producing u barrel oil
nd barrel Of water before treatment.
urlng the period represented by this
raph, the wei produced 5000 barerls OF
- aHA SLOW DANEtl1 or wafer. inc In .
resting feature OF this curve A that
ie water production declined at q very
IPid rae until at the end OF eight
onths when Il began producing the
.he amount Oh water as before acidiz-
GAS WELL INCREASES
The treatment OF gas wells has become
accepted production practice in many
cas- An example is given in produc-
On records OF ten gas wells located IA
e oklahoma City Field and producing
ON the Oswego lime
Before aeidizing, the average open flow
'tentlal on these wells was apDroxf-
ately 2.75OO00 cubic feet per day. Since
ny %oso OF the open flow can be pro-
100 cubic feet OF gas were available
consumption. After acldizlng, how
er. these same wells had an average
en- HOW potential In excess OF 12O00,OUO
urther analysis reveals that during
100 days covered by this study, the
erage well produced a total OF Dog
Ia FnnN -.