<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1390-0129</journal-id>
<journal-title><![CDATA[Revista Politécnica]]></journal-title>
<abbrev-journal-title><![CDATA[Rev Politéc. (Quito)]]></abbrev-journal-title>
<issn>1390-0129</issn>
<publisher>
<publisher-name><![CDATA[Escuela Politécnica Nacional]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1390-01292018000200029</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Evaluación de la Disminución del Depósito de Parafinas Empleando Modificadores de Cristales en Petróleo Liviano]]></article-title>
<article-title xml:lang="en"><![CDATA[Paraffin Deposit Decrease Evaluation Using Crystal Modifiers in Light Crude Oil]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Heredia]]></surname>
<given-names><![CDATA[Francisco]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vera]]></surname>
<given-names><![CDATA[Edwin]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Guzmán-Beckmann]]></surname>
<given-names><![CDATA[Liliana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Escuela Politécnica Nacional  ]]></institution>
<addr-line><![CDATA[ Quito]]></addr-line>
<country>Ecuador</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<volume>41</volume>
<numero>1</numero>
<fpage>29</fpage>
<lpage>38</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_arttext&amp;pid=S1390-01292018000200029&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_abstract&amp;pid=S1390-01292018000200029&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_pdf&amp;pid=S1390-01292018000200029&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: La presencia de depósitos de parafinas en las paredes de tuberías de transporte de crudo puede ocasionar pérdidas de producción de petróleo debido al bloqueo parcial o total que estos pueden causar, la posibilidad de prevenir la formación de incrustaciones es importante para la industria petrolera. En esta investigación se evaluó mediante el método del dedo frío la relación del perfil de temperatura de la capa límite térmica (formada entre una superficie fría y el crudo caliente) con la cantidad obtenida de depósitos, la eficiencia de cuatro modificadores de cristales (M.C.) y la severidad de los depósitos de parafinas. El equipo dedo frío se construyó en los laboratorios de la Escuela Politécnica Nacional. Se trabajó con petróleo proporcionado por Tecpetrol, empresa operadora del Bloque 49 de la Amazonía Ecuatoriana, al caracterizar este crudo se determinó que tiene 31,2 ºAPI y una temperatura de enturbiamiento de 28,7 ºC. Los resultados de la investigación fueron obtenidos al mantener la temperatura de la muestra de crudo a 60,0 ºC y temperaturas de la pared fría de 20,0 ºC y 12,0 ºC. La reducción de la temperatura de la superficie fría ocasionó una mayor región a temperatura inferior a la de enturbiamiento que favoreció el aumento de la cantidad de depósitos. El incremento de la velocidad inicial de deposición debido a la reducción de temperatura fue de 4,1×10-3 g/cm2×h a 4,9×10-3 g/cm2×h. El M.C.2 a 3.000 ppm en 100 mL de crudo deshidratado alcanzó eficiencias en la reducción de los depósitos superiores al 90,0 %.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: Paraffin deposits on the oil transport tubing surface can produce losses due to partial or total blocking of the pipes. The possibility of preventing the scurf appearance is of interest to oil industry. This research evaluates the relationship between the thermic boundary layer temperature profile (border between a cold surface and the hot oil) and the amount of deposits using the cold finger method. As well, it evaluates four crystal modifyers (C.M.) efficiency and their effects on the paraffin deposits. Cold finger equipment was built at Escuela Politécnica Nacional University. And, the oil was obtained from Tecpetrol (an oil enterprise) which operates at Bloque 49 in the amazon region of Ecuador. This oil measured 31,2 °API and a cloud point of 28,7 °C. The experiments with the cold finger were obtained maintaining the sample oil at 60,0 °C and the cold surface either at 20,0 °C or 12,0 °C. The low temperature of the cold finger surface generated a region where the temperature was lower than the cloud point which stimulated the increase of the amount of paraffins deposited. The low temperature increased the initial deposit velocity from 4,1×10-3 g/cm2×h to 4,9×10-3 g/cm2×h. The most efficient method was C.M.2. at 3.000 ppm over 100 mL of oil reaching a deposit reduction efficiency more than 90,0 %.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[depósitos de parafinas]]></kwd>
<kwd lng="es"><![CDATA[inhibidores de parafinas]]></kwd>
<kwd lng="es"><![CDATA[eficiencia del modificador de cristal]]></kwd>
<kwd lng="es"><![CDATA[dedo frío]]></kwd>
<kwd lng="en"><![CDATA[paraffin deposition]]></kwd>
<kwd lng="en"><![CDATA[paraffin inhibitors]]></kwd>
<kwd lng="en"><![CDATA[crystal modifier efficiency]]></kwd>
<kwd lng="en"><![CDATA[cold finger]]></kwd>
</kwd-group>
</article-meta>
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