paraffin wax deposition and fouling
paraffin wax deposition and fouling
paraffin wax deposition and fouling
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
-<br />
iuctoov <strong>and</strong> dorov concluded<br />
hat terrncrature affectecj<br />
cortuosition of uaraffin deoosits; also that bocauae there is a<br />
range of <strong>paraffin</strong>s dissolved in crude oils, t:cese will scuarate out<br />
according to their melting ooint. As the temuerature difference<br />
between the tube wall <strong>and</strong> the oil increases the deposits become<br />
looser since on r<strong>and</strong> cooling both high <strong>and</strong> low melting noint <strong>paraffin</strong>s<br />
wI crystallize simultaneously lorming a weak porous structure wtn<br />
cavities full of oil.<br />
Tinally, the rapid fall in the quantity <strong>and</strong><br />
meting point, as the oii temoerature decreases, confirms that the<br />
mechanism of <strong>paraffin</strong> denosition is one of crystal growth directly<br />
on a surface.<br />
o_esni et a... stucaen tae e:ec. 0... crune oi... temperature<br />
on :Daraf:nn c.euostcn. The exper1menta nrocemure conssuen 0:<br />
pouring a tca_ desalled cruae oil tnto a steel tuoe (O cm<br />
_ong<br />
1.5 cm diameter) rlaced in a constant temperature bath. The oi. uas<br />
kept stirred for the duration of the exueriment, which was one hour.<br />
At the end of each experiment the oil was poured off the tube <strong>and</strong><br />
the tube weited to record the amount of uaraffin deoosited. :n<br />
exueraents a; success1vey<br />
temneratures tne para::in aepcsl;ec.<br />
in the previous exreriment was left in the tube. See fi. 2.5.2.—.<br />
Above 25°C evidently no <strong>deposition</strong> occurred, but a ZLll o<br />
adhered to the tube wall.<br />
At 25°C <strong>deposition</strong> started when the oil<br />
ter:er;ure fell oeow tne c_oum point. e.ow 5°C meros;;oa<br />
mown,<br />
acaarent_y cecause ot consmeraoe increase ifl Oi VSCDSiy.<br />
elow —5°Z demosition increased, nrobally because the <strong>paraffin</strong><br />
nartices a;lomera;ed e.ad because more <strong>and</strong> more low melliaf noini<br />
parafffns crysta..;zen.<br />
-. .. -<br />
.essen arm :C.1eu<br />
-<br />
staten ;nat tne ....css o: temoera;ure o: tue<br />
(30)<br />
came c: was tue razor :nctor rvo..ved ;n tue :orzat;or C..<br />
At lo,er terteratures <strong>paraffin</strong> deposits are acre crt:Z_ine<br />
arc. ;nere:ore narc..er ann more tign;y ne...c. tofetner. non coo.:rg C:
Change language