Catoctin clarion. [volume] (Mechanicstown, Md.) 1871-1940, 1920-08-05
EVAPORATION OF
OIL HEAVY LOSS
$27, 900, 900 a Year Lost in Mid
Continent Field Alone.
IT ESCAPES AS GASOLINE

From Two-Thirds to Four-Fifths of
the Loss Gould Be Saved by Protect
ing the Oil From the Air, Says Pc
troIeum Engineer in Report to the
Government Bureau of Mines
Problem Taken Up at Experiment
Stations.
In report sent to the United States
bureau of mines, j. III. Virgins, as
siStant petroleum engineer, says that
the evaporation of crude oil causes
one of the largest single losses to
which the oil is subjected aSer il is
taken from the ground. The few days
which crude oil is stored on the lease
before being taken by the pipe line
causes an aggregate loss per year
from evaporation estimated at ID
10000 gallons of gasoline in the mid.
continent field alone. This has a value.
at % cents per gallon, of $26, 10000
and represents about 8 per cent Of the
total gasoline produced in the United
States from all fields and all sources.
This problem Is now being taken up
at the Bartlesville experimental sta
tion and at the San Francisco office
of the bureau of mines. Mr.. Virgins
In preparing his report covered only
the mid-cOntinent field, whose output
represents more than one-half the
United States production. Some Of
the important features of his report
are as follows:
Features Of Report.
1.-THE rate at which oil OF given
quality and under given temperature
conditions will evaporate depends
chiefly on the way 1t Is handled. The
ordinary method IS to pump the oil
from the well, force it through pipe
line gathering system, and then into
tank by means of Oversh0t connec-
tons In this tank, called flow tank,
any free water is separated by gray
ity, then the oil is led by another pipe
to the lease storage tank. The latter
Is also filed by overShot connections
which permit the oil to fall 8 to ID
feet and splash into the tank, causing
spray. After standing In sthis tank
perhaps two to ten days the oil Is
run by the pipeline company by
means of pumps and pipe lines To the
large steel storage tanks. These have
bottom connections and nearly gas
tight roofs. The oil is run from here
TO large tank farms, or directly to the
refinery by pipe lines or tank cars.
Each Of these steps constitutes
different class as regards rate Of evap-
Grafton. These classes may be divided
as follows: Cd Filling tank by over
shot connection; (2) filling tank
by bottom connecti"n&; (O storage in
small unprotected tanks on the lease:
(4) storage In small tanks on the
lease which have some protection such
as shading or an alright jacket, and
90 storage in $1,000 or $1,000 barrel
steel tanks which have so-called gas
tight roofs.
"Filling the tank by overshot con
nections Is the cause of the most rap
id loss. The amount of this loss de-
ponds on several variableS, such as
the height from which the oil falls,
the velocity and size OF the stream,
and the size of the tank as compared
with the time required to fill it. 'Sev
eral tests were made which show that
the loss in "a hours from such condi-
tons ranges from l to 2k per cent of
the original volume In the summer
time. Evaporation during the storage
on the lease in unprotected tanks
shows high rate. Data obtained
from some of the largest independent
producing companies in the md-conti-
nent field show that the average period
of storage Is five days. In that time
oil stored in a 25O-barrel steel tank,
unprotected, will lose 90 to 81 per
cent by volume; oil stored in 5OO-bar-
rel steel unprotected tanks about 2
per cent; 1,600-barrel wooden tank,
which is protected by house that
acts both as a shade and windbreak,
will lose about IL per cent. The above
figures are for summer conditions, but
tests covering this phase Of the sub
ject were run for summer, autumn and
winter.
Conclusions Drawn.
"Data were kept on semi-monthly
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