paraffin wax deposition and fouling

and surface proueriez reapectlvely_ ‘dcn invcattating the cect
ann comuare :ug. 2..3.2). Uhen derosittng on a surlace wtan an
- 25
in nature on which anot:uer deposit did not form (see fig. 2.3.5.
as time went on, leaving a very thin film of wax auparently granular
Itered the deuoaitior behaviour. Taen depositing on a i’rcshly
diatillation residua to the hostane—wax solution drnnticrilly
—
oil inaustry, Th is defined as the formation of any rrcddhnctt;lg
paraffin wan—kerosene—toluene solution prevented the formation of a
struc:z’al la;ice of raraffin crystals.
addition, the occlusion of additive molecules in a deposit resulto
tao :o:c.ae: cu Dara:1:: auos::uo:: ts o: _on; smun_ng
(_..
::uravev et al i-euoried -:ha; asuhaitenes (3.5 er cent) in a
firmly anchored and may be swept off by the flowing fluid. :n
a paraffin crystal may nucleate on the film, it is no; as
irg the paraffin molecules from penetrating the film. Then, even
it is capable 0f maintaining any :ore—adsorbed film, thus prevent—
failure. Thrthermore, when an additive is rresent in a solu;ic::
in diminishing the cohesive strength of the deposit and allows
the snielding effect of the paraffin derosit itself, ‘out succeens
to result in the formation of a detectable adsorbed film because oi
any adsorbed film the presence of an additive in a solution fails
Patton and Jessen :oostulated that when the surface is free oi
in one riece.
to the rre—adsorbed film. The deposit simply slid off the specimen
was removed from the arraratus; in no case did the denosit adhere
that observed without an adsorbed film
1 except when the specimen
in decreased cohesive s:ren;h and thus encouroges cohesive dha:e.
of additives they found that the addition of a smai amount of
adsorbed distillation residua film the deposition was identical to
:oolichcd surface an opaque cienosit was formed whica neeled off