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Wax deposition data for a Brazilian crude oil was investigated using a facility designed to study flow assurance problems related to waxy crude oils. This work reports the preliminary efforts behind validating the pressure drop methods in place for identifying deposition, i.e., isothermal and nonisothermal flows were evaluated, to confirm whether it was possible to differentiate between temperature gradient effects, and wax deposition. Additionally, deposition experiments show a phenomenon that is not commonly reported in the literature. Once the oil’s temperature was below the wax appearance temperature and the water temperature at 5 °C, the deposit did not start to build up immediately; it only began after a period of time. Under some conditions the pressure drop only began increasing after 1 day. These results show that, at least for highly paraffinic crudes, models based on molecular diffusion alone cannot predict when and where the deposit will form, which is a major concern in the industry. We believe that other mechanisms such as shear dispersion, Brownian diffusion, and the non-Newtonian behavior of waxy crudes at low temperatures should be considered. In this experimental setup two different ways were used to measure deposit thickness: (1) pressure drop and (2) weight of the deposit.

Magnetic hyperthermia (MH) is the phenomenon of increasing the temperature of a system with magnetic nanoparticles (NPs) subjected to an alternating magnetic field (AMF). This phenomenon occurs as the energy from the magnetic field is transformed into heat by mechanical (Brownian relaxation) and/or magnetic (Neél relaxation) magnetization reversal. In this work, we developed an experimental setup to test the use of MH for industrial applications. The liquid's viscosity decreases as the temperature increases, and liquids with high viscosity are present in several industries (e.g., O&G, pharmaceutical, chemical, and food), where a reduction in viscosity can translate into lower costs and greater profitability, for instance, in some industries, by decreasing the pressure drop and hence increasing the flow rate and in others by avoiding problems that occur at low temperature. Our pilot apparatus was built to investigate the hyperthermia effect when a mixture of viscous liquids and NPs, with an average size of 8 nm (transmission electron microscopy), flows through an AMF. In this study, three different configurations were tested, two static, with mixture samples of 1 and 100 mL, and one under dynamic flowing conditions. Two important results should be highlighted: (1) static experiments with 1 and 100 mL had similar SAR [W/g] values, demonstrating the viability of scaling up and (2) there was an increase in the temperature of the colloid flowing through the AMF. It was therefore possible to observe a clear increase in the liquid's temperature when subjected to an AMF, for all condition cases. The results suggest that this technology can be applied on an industrial scale by optimizing the coils and NP properties.