The Washington herald. [volume] (Washington, D.C.) 1906-1939, 1921-12-25
Use TWO METHODS
IN DETILATlON OF
LUBRICATINC OIL
Producers Get Best Re-
suits from Heaviest
Hydrocarbons.
LARGE = INDUSTRY
Fractional and Destructive
Processes Described
In Detail.
LARGE INDUSTRY

me manufacture of lubricating
pills from crude petroleum is a
|oranch Of q very extensive indus
fry. The great variety of hydro
faroons of which the crude oils are
composed affords material for the
nanufaeture OF numerous products.
Fhs nshtest and most volatile
hydrocarbons compose crude naph-
Fha, from which rhigolene. gasoline,
petrol or motor spirit. and SINH
ar products are obtained
These liquida which are devoid
all lubricating property, form
ighly volatile and inhammable
spirtts." useA fef driving motors,
ry cleaning. 1naking air gas, car
ureting coal ;1As. and for solvent
nd other purposes. OF these prod
cts the motar spirit. is now by
ar the most Important CONNER
ially. Hydrocarbons of higher
polling point and specific gravity
which are still too fluid and vola-
to be used for lubricating.
omposs the Illuminating oils of
fommercs known as kerosene,
Petroleum. paraffin, etc. The heav-
est and least volatile hydrocar-
Pons are alone used for the manu-
acture of lubricating oils, parafin
YAK, etc. The refner's business Is
70 separate the various pnoducts
rom the crude oil and purify them
or use, and this he does by distil-
alton and chemical treatment
DfstfIlation Methods.
The value OF distillation depends
pon the fact that the different
Constituents of the crude oil boil
md volatilize at different temper
tures, the naphtha coming over
rst. then the Illuminating oils.
hen some intermediate" oils used
Tor gas-making. or destructively
distilled so as to increase the guam
ity of Illuminating oil. leaving
he heaviest hydrocarbons. unless
he distillation Is continued to
pryness. as a residue in the still
By separate fractional distilla-
Ion the naphtha Is subsequently
3plit up int omotor spirit. gasoline,
tc., and the residuum into lubri-
ating oils of various grades. para
I'm wax. and asphalt or coke.
In practice. however, the dis
3illation. especially of the heavier
Fractions Is never a simple process
ff separation. as Is proved by the
fact that products are found In
the distillates which do not exist
| n the original liquid. During the
1istillation. the heavier hydn0car-
ions vapors partly condense on the
Upper and cooler part of the still
Ind fall back into the boiling
kauid, while. in distilling the heavy
3il, the boiling has to be very Wig
Srous to keep up the stream of
tapor issuing from the retort,
Which necessitates a strong hre
nd q high temperature at the Bit
ON and sides of the ret>rt.
Increase illuminating OIL.
The prolonged and excessive
heating to which the heavier by
krocarbons are thus subjected
kradually splits them up, partly
into permanent gases (marsh gas
Ind hydrogen), partly into lqulo
hydrocarbons of lower boiling-point
Ind viscosity. which distil over,
md partly into tarry products
which remain in the sun IL mas
Ken found, in fact, that by set
SFn1 the still so that the upper
H.rt is kept cool, and conducting
r.. distillation slowly in order to
6ronots condensation. or by dis
f1IIn9 under increased pressure and
r -aIsing the boiling temperature
n the LIQUID, the destructive dis
kTu,tJon or cracking" of tEe
6.,vI.r hydrocarbons may be pro-
6ro,.d 70 such an extent as largely
II increase the natural yield OF IL
oil at the expense OF
L. haavier fractions.
/ Trpe quantities OF cruuo
lstroleum, in which the resiouurh
|. not of special value for the
fr.,aration of lubricants, are dis
tu.d IN this way in the United
Eat.s. the illuminating distillate
{sI,g increased from a normal pro-
lor,ion OF about so per cent 10 as
b,rh a. 70 or rs per cent, and the
|. ,tsuurn reduced to as little as
err cent.
| Tbsre are two methods Of distilla-
H., known as fractional and de-
kructive distillation;
| fractional distillation may De
[.rrI.d on under a vacuum or at
hospherio pressure.
| D..tructice distillation Is carried
II AT atmospheric pressure or at
LINER pressure up to about 80
ounds.
Fractional Oscillation
In vacuum stills the distillation
W., place under a partial vacuum
|, a result OF which the tempera-
kIre Of the oil in the still during
b,,illation does not exceed $50 TO
IN degrees Fahrenheit. which Is
~ compared with the ordinary
hethod Of distillation used for or
|inary grades of cylinder stock
The crude oil Is preheated to q
of about 200 degrees by
beans of q specially designed fore
Farmer. This is a set of tubes
hrouSh which crude oil is pumped
III its way to the still. These tubes
IA jacketed. The hot yapors from
he still pass through the jacket to
be condenser, preheating the crude
I'M 70 q temperature OF about 200
(sgrees-
A part Of the lighter oils will
|yaporate at a temperature of 100
10 $50 degrees, which means that
|one Of the naphtha is given up in
his forewarmer before the crude
I'M enters the still This system of
lreheating Is very economical and
|aves hundreds OF dollars in fuel
Der year.
Burning oils (kerosene. etc.) come
In at $50 degrees to $50 degrees.
this a product known as
le-run stock comes off up to a
temperature of about 500 degrees.
This re-run Is later re-distilled to
laphtha until nothing but tar is
kft. Everything that evaporates
(bove this temperature Of 500 de-
frees and up TO the time that the
|istillation of the crude in the still