Vol. 10 � 6, 2020 p 610-619| Science & Technologies: Oil and Oil Products Pipeline Transportation

Pages	Article name, authors, abstract and keyword
610-619	Study of the causes for wax deposition under the operating conditions of main oil pipelines Rustam Z. Sunagatullin ^a, Rinat M. Karimov ^b, Radmir R. Tashbulatov ^b, Boris N. Mastobaev ^b ^a Pipeline Transport Institute, LLC (Transneft R&D, LLC), 47a Sevastopolsky Prospect, Moscow, 117186, Russian Federation ^b Ufa State Petroleum Technological University, 1 Kosmonavtov Str., Ufa, 450062, Russian Federation DOI: 10.28999/2541-9595-2020-10-6-610-619 Abstract: The results of investigations of the main causes and the most significant factors of intensification of paraffin deposition in main oil pipelines are presented. A comprehensive analysis of the composition and properties of commercial oils and their sediments was carried out, according to which phase diagrams of equilibrium of oil dispersed systems were obtained using the example of commercial oils from Bashkir fields. Based on the phase diagrams, a curve of wax oil saturation was constructed, the analysis of which confirms that the existing thermobaric conditions during the operation of main oil pipelines do not allow transporting oil without the risk of waxing. It was noted a special influence of the value of the temperature gradient in the near-wall zone and the imbalance of the ratio of high-molecular oil components in commercial batches formed in the process of joint pumping on the intensity of waxing of sections of oil pipelines complicated by deposits, which was confirmed by statistical data on the frequency of pigging. The regularities obtained in this way are proposed to be used as an express method for predicting complications associated with intensive waxing of main oil pipelines. In order to quickly assess the risks of waxing of sections of main oil pipelines, an indicator is introduced that characterizes the ratio of the content of solid paraffins to the total content of resins and asphaltenes of oil, called the criterion of instability of a commercial oil batch. Keywords: wax deposition, oil, main pipeline, thermobaric conditions, phase diagram, temperature gradient, frequency of pigging, criterion of instability. For citation: Sunagatullin R. Z., Karimov R. M., Tashbulatov R. R., Mastobaev B. N. Study of the causes for wax deposition under the operating conditions of main oil pipelines. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2020;10(6):610�619. References: [1] Armensky �. �., Novoselov V. F., Tugunov P. I. Study on thermal effects and dynamics of paraffin deposition in pipelines. Oil and Gas. 1969(10):77�80. (In Russ.) [2] Voznyak �. P., Hazgilov I. H., Voznyak L. V. Paraffin deposits thickness change over pipeline length and time. Exploration and Development of Oil and Gas Fields. Republican inter-agency research and technology collection. 1975(12):113�116. (In Russ.) [3] Kolesnik I. S., Lukashevich I. P., Susanina �. G. Temperature influence on waxing process. Oil and Gas. 1971(2):85�88. (In Russ.) [4] Lyapin �. Y., �stakhov �. V., Mikhalyov Y. L. Study of the wax crystallization temperature in oil in order to reduce the formation of asphalt-resin-paraffin deposits. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2017;7(6):28�35. (In Russ.) [5] Sunagatullin R. Z., Karimov R. M., Tashbulatov R. R., Mastobaev B. N. Modeling the thermal-hydraulic effect of wax layer. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2019;9(2):158�162. (In Russ.) [6] Sunagatullin R. Z., Karimov R. M., Dmitriev M. E., Baykova M. I. Experimental studies of the operational properties of asphalteneresin-paraffin deposits formed in main oil pipelines. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2018;8(4):398�406. (In Russ.) [7] Kolesnik I. S., Lukashevich I. P., Susanina �. G. Study on paraffin deposits adhesiveness to steel surface. Oil Products and Raw Hydrocarbons Transportation and Storage. 1972(5):17�20. (In Russ.) [8] Tronov V. P. Theoretical evaluation of the effect of physical properties of surfaces, processing quality, and other factors on the intensity of paraffin deposition. In: Problems of Geology, Development, Drilling and Oil Production. Bugulma: TatNII Publ.; 1962. Vol. 4. P. 400�412. (In Russ.) [9] Tronov V. P. On the mechanism of effect of the nature of surfaces on their paraffinization. Issues of wells drilling, oil production and economy. 1968(11):191�200. (In Russ.) [10] Evdokimov I. N., Eliseev N. Y., Allahverdieva D. �. Influence of universal molecular mechanisms of oil systems performance change. Research report. Moscow: Gubkin Russian State University of Oil and Gas Publ.; 2002. 79 p. (In Russ.) [11] Karimov R. M., Mastobaev B. N. Rheological particularities of the West Kazakhstan oil blend. Transportation and Storage of Oil Products and Raw Hydrocarbons. 2011(2):3�7. (In Russ.) [12] Karimov R. M., Mastobaev B. N. Joint transport of high-viscosity and high-hardening oils of Western Kazakhstan through the Uzen�Atyrau�Samara oil pipeline. Transport i khraneniye nefteproduktov i uglevodorodnogo syr�ya = Transport and Storage of Oil Products and Hydrocarbons. 2012(1):3�6. (In Russ.) [13] Revel-Muroz P. A., Bakhtizin R. N., Karimov R. M., Mastobaev B. N. Joint usage of thermal and chemical stimulation tech nique for transportation of high viscosity and congealing oils. SOCAR Proceedings. 2017(2):49�55. (In Russ.) [14] Revel-Muroz P. A., Bakhtizin R. N., Karimov R. M., Mastobaev B. N. Joint transportation of heavy and wax oil blended. SOCAR Proceedings. 2018(2):65�70. (In Russ.) [15] Sunagatullin R. Z., Karimov R. M., Mastobaev B. N. Influence of the temperature gradient at the �stream-wall� interface on the paraffin deposition rate. Abstracts from the XIV International academic and research practitioner-driven conference �Pipeline transport�2019�; 2019 May 23�24; Ufa, Russian Federation. Ufa: USPTU Publ.; 2019. P. 132�133. (In Russ.)

Pages

Article name, authors, abstract and keyword

610-619

Study of the causes for wax deposition under the operating conditions of main oil pipelines

Rustam Z. Sunagatullin ^a, Rinat M. Karimov ^b, Radmir R. Tashbulatov ^b, Boris N. Mastobaev ^b

^a Pipeline Transport Institute, LLC (Transneft R&D, LLC), 47a Sevastopolsky Prospect, Moscow, 117186, Russian Federation
^b Ufa State Petroleum Technological University, 1 Kosmonavtov Str., Ufa, 450062, Russian Federation

DOI: 10.28999/2541-9595-2020-10-6-610-619

Abstract: The results of investigations of the main causes and the most significant factors of intensification of paraffin deposition in main oil pipelines are presented. A comprehensive analysis of the composition and properties of commercial oils and their sediments was carried out, according to which phase diagrams of equilibrium of oil dispersed systems were obtained using the example of commercial oils from Bashkir fields. Based on the phase diagrams, a curve of wax oil saturation was constructed, the analysis of which confirms that the existing thermobaric conditions during the operation of main oil pipelines do not allow transporting oil without the risk of waxing. It was noted a special influence of the value of the temperature gradient in the near-wall zone and the imbalance of the ratio of high-molecular oil components in commercial batches formed in the process of joint pumping on the intensity of waxing of sections of oil pipelines complicated by deposits, which was confirmed by statistical data on the frequency of pigging. The regularities obtained in this way are proposed to be used as an express method for predicting complications associated with intensive waxing of main oil pipelines. In order to quickly assess the risks of waxing of sections of main oil pipelines, an indicator is introduced that characterizes the ratio of the content of solid paraffins to the total content of resins and asphaltenes of oil, called the criterion of instability of a commercial oil batch.

Keywords: wax deposition, oil, main pipeline, thermobaric conditions, phase diagram, temperature gradient, frequency of pigging, criterion of instability.

For citation:
Sunagatullin R. Z., Karimov R. M., Tashbulatov R. R., Mastobaev B. N. Study of the causes for wax deposition under the operating conditions of main oil pipelines. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2020;10(6):610�619.

References:
[1] Armensky �. �., Novoselov V. F., Tugunov P. I. Study on thermal effects and dynamics of paraffin deposition in pipelines. Oil and Gas. 1969(10):77�80. (In Russ.)
[2] Voznyak �. P., Hazgilov I. H., Voznyak L. V. Paraffin deposits thickness change over pipeline length and time. Exploration and Development of Oil and Gas Fields. Republican inter-agency research and technology collection. 1975(12):113�116. (In Russ.)
[3] Kolesnik I. S., Lukashevich I. P., Susanina �. G. Temperature influence on waxing process. Oil and Gas. 1971(2):85�88. (In Russ.)
[4] Lyapin �. Y., �stakhov �. V., Mikhalyov Y. L. Study of the wax crystallization temperature in oil in order to reduce the formation of asphalt-resin-paraffin deposits. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2017;7(6):28�35. (In Russ.)
[5] Sunagatullin R. Z., Karimov R. M., Tashbulatov R. R., Mastobaev B. N. Modeling the thermal-hydraulic effect of wax layer. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2019;9(2):158�162. (In Russ.)
[6] Sunagatullin R. Z., Karimov R. M., Dmitriev M. E., Baykova M. I. Experimental studies of the operational properties of asphalteneresin-paraffin deposits formed in main oil pipelines. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov�Science & Technologies: Oil and Oil Products Pipeline Transportation. 2018;8(4):398�406. (In Russ.)
[7] Kolesnik I. S., Lukashevich I. P., Susanina �. G. Study on paraffin deposits adhesiveness to steel surface. Oil Products and Raw Hydrocarbons Transportation and Storage. 1972(5):17�20. (In Russ.)
[8] Tronov V. P. Theoretical evaluation of the effect of physical properties of surfaces, processing quality, and other factors on the intensity of paraffin deposition. In: Problems of Geology, Development, Drilling and Oil Production. Bugulma: TatNII Publ.; 1962. Vol. 4. P. 400�412. (In Russ.)
[9] Tronov V. P. On the mechanism of effect of the nature of surfaces on their paraffinization. Issues of wells drilling, oil production and economy. 1968(11):191�200. (In Russ.)
[10] Evdokimov I. N., Eliseev N. Y., Allahverdieva D. �. Influence of universal molecular mechanisms of oil systems performance change. Research report. Moscow: Gubkin Russian State University of Oil and Gas Publ.; 2002. 79 p. (In Russ.)
[11] Karimov R. M., Mastobaev B. N. Rheological particularities of the West Kazakhstan oil blend. Transportation and Storage of Oil Products and Raw Hydrocarbons. 2011(2):3�7. (In Russ.)
[12] Karimov R. M., Mastobaev B. N. Joint transport of high-viscosity and high-hardening oils of Western Kazakhstan through the Uzen�Atyrau�Samara oil pipeline. Transport i khraneniye nefteproduktov i uglevodorodnogo syr�ya = Transport and Storage of Oil Products and Hydrocarbons. 2012(1):3�6. (In Russ.)
[13] Revel-Muroz P. A., Bakhtizin R. N., Karimov R. M., Mastobaev B. N. Joint usage of thermal and chemical stimulation tech nique for transportation of high viscosity and congealing oils. SOCAR Proceedings. 2017(2):49�55. (In Russ.)
[14] Revel-Muroz P. A., Bakhtizin R. N., Karimov R. M., Mastobaev B. N. Joint transportation of heavy and wax oil blended. SOCAR Proceedings. 2018(2):65�70. (In Russ.)
[15] Sunagatullin R. Z., Karimov R. M., Mastobaev B. N. Influence of the temperature gradient at the �stream-wall� interface on the paraffin deposition rate. Abstracts from the XIV International academic and research practitioner-driven conference �Pipeline transport�2019�; 2019 May 23�24; Ufa, Russian Federation. Ufa: USPTU Publ.; 2019. P. 132�133. (In Russ.)