The role of fine particles in the stability of emulsion in the naphthenic froth treatment (NFT) process

This study investigates the role of fine particles in stabilizing emulsion in the naphthenic froth treatment (NFT) process. The characterization results of different types of solids collected from the diluted bitumen froth indicate that kaolinite is the dominant clay mineral in the composition of NFT solids. There were differences in the mineralogy of the fine samples depending on the phase (carrier fluid) from which the samples were collected. FTIR analysis shows that the fines that remain in the diluted bitumen even after several hours of sample retention time are mainly kaolinite, though the presence of other minerals such as siderite is very likely. Moreover, the presence of organic functional groups on the surface of the particles is confirmed for all types of solids in the FTIR analysis, regardless of the washing and drying procedures employed. Inspection of the different layers of the diluted bitumen via micrography and measurement of the solids concentration shows higher fine content and smaller particles in the top layer, a dire situation for destabilizing the emulsion in the top layer, supported by the observation that the water droplets in this layer are tiny. Solid partitioning tests revealed the solid particles migrate to the interfacial region and the aqueous phase. The concentration of particles increased in the interfacial region with the presence of asphaltene in the oil phase (dominant effect) and the increased polarity of the oil. The wettability measurements show that without the coverage of solid particles with organics (asphaltene-resin molecules), the fine particles are extremely hydrophilic. The adsorption of asphaltene-resin matter on the fine particles increased the hydrophobicity of the fines, a situation that promotes the partitioning of the fine particles at the interfacial region and the stability of the droplets. It was observed that the contact angle increased with the decreasing polarity of the oil phase. In the interfacial tension measurements, the fine solids with minimal asphaltic matter coverage did not remain suspended in the oil phase and either sedimented rapidly or migrated to the air-oil interface, unlike the organics-covered solids which remained immersed in oil. No decrease in the interfacial tension was recorded for the water-oil systems in the presence of fine solids. Interfacial rheology measurements illustrate the viscoelastic behavior of the interfacial film at lower frequencies and higher fine particle concentrations. We conclude that if not for the interaction between the asphaltic matter and the fine particles, the emulsion stability by fine particles would have been very unlikely

Gas migration through cement slurries analysis: A comparative laboratory study

Cementing is an essential part of every drilling operation. Protection of the wellbore from formation fluid invasion is one of the primary tasks of a cement job. Failure in this task results in catastrophic events, such as blow outs. Hence, in order to save the well and avoid risky and operationally difficult remedial cementing, slurry must be optimized to be resistant against gas migration phenomenon. In this paper, performances of the conventional slurries facing gas invasion were reviewed and compared with modified slurry containing special gas migration additive by using fluid migration analyzer device. The results of this study reveal the importance of proper additive utilization in slurry formulations. The rate of gas flow through the slurry in neat cement is very high; by using different types of additives, we observe obvious changes in the performance of the cement system. The rate of gas flow in neat class H cement was reported as 36000 ml/hr while the optimized cement formulation with anti-gas migration and thixotropic agents showed a gas flow rate of 13.8 ml/hr

Prediction of permeability from well logs using a new hybrid machine learning algorithm

Permeability is a measure of fluid transmissibility in the rock and is a crucial concept in the evaluation of formations and the production of hydrocarbon from the reservoirs. Various techniques such as intelligent methods have been introduced to estimate the permeability from other petrophysical features. The efficiency and convergence issues associated with artificial neural networks have motivated researchers to use hybrid techniques for the optimization of the networks, where the artificial neural network is combined with heuristic algorithms.This research combines social ski-driver (SSD) algorithm with the multilayer perception (MLP) neural network and presents a new hybrid algorithm to predict the value of rock permeability. The performance of this novel technique is compared with two previously used hybrid methods (genetic algorithm-MLP and particle swarm optimization-MLP) to examine the effectiveness of these hybrid methods in predicting the permeability of the rock.The results indicate that the hybrid models can predict rock permeability with excellent accuracy. MLP-SSD method yields the highest coefficient of determination (0.9928) among all other methods in predicting the permeability values of the test data set, followed by MLP-PSO and MLP-GA, respectively. However, the MLP-GA converged faster than the other two methods and is computationally less expensive

Evaluation of mobile phone-based tele-monitoring of cystic fibrosis patients during the COVID-19 pandemic: A 3-year experience in Iran

Background: Telemedicine has been used for cystic fibrosis (CF) in a wide range of signs and symptoms even before the COVID 19 pandemic, however, little is known about the health consequences and use of specific health care for cystic CF. This study aimed to evaluate the evolution of clinical trends and data related to mobile based monitoring activities in CF patients at home for 3 years. Methods: This is a semi experimental single group study. Forty five CF patients under 7 years' old who were referred to the Masih Daneshvari Hospital between 2018 and 2021 were selected. A mobile phone_based customized Short Message Service (SMS) application used to monitor patients. Remotely monitored variables included the amount and color of sputum, cough, wheezing, and shortness of breath at rest. SPSS using Chi square and Friedman tests. Results: The condition of patients based on the number and type of cough increased sputum, decreased appetite, fatty stool, fever and dyspnea, headache, noninvasive ventilation, and drug comfortably remained almost unchanged in the study of the 1st, 2nd, and 3rd years, and the studied parameters did not show a significant difference (P > 0.05). Of course, the number of outpatient visits decreased significantly (P value: 0.02). The respiratory rate and arterial oxygen saturation variables were almost the same in three consecutive annual measurements (P values: 0.544 and 0.639, respectively). Conclusion: Telemedicine is a method that is useful in the follow up of chronic diseases such as CF and improves the quality of life and reduces the deterioration of lung function; therefore, there is less need for invasive treatments in the long run, and a fundamental change in referral motivation brings to the hospital