Experimental investigation and simplistic geochemical modeling of CO2 mineral carbonation using the mount tawai peridotite

In this work, the potential of CO2 mineral carbonation of brucite (Mg(OH)2) derived from the Mount Tawai peridotite (forsterite based (Mg)2SiO4) to produce thermodynamically stable magnesium carbonate (MgCO3) was evaluated. The effect of three main factors (reaction temperature, particle size, and water vapor) were investigated in a sequence of experiments consisting of aqueous acid leaching, evaporation to dryness of the slurry mass, and then gas-solid carbonation under pressurized CO2. The maximum amount of Mg converted to MgCO3 is ∼99%, which occurred at temperatures between 150 and 175 °C. It was also found that the reduction of particle size range from >200 to <75 μm enhanced the leaching rate significantly. In addition, the results showed the essential role of water vapor in promoting effective carbonation. By increasing water vapor concentration from 5 to 10 vol %, the mineral carbonation rate increased by 30%. This work has also numerically modeled the process by which CO2 gas may be sequestered, by reaction with forsterite in the presence of moisture. In both experimental analysis and geochemical modeling, the results showed that the reaction is favored and of high yield; going almost to completion (within about one year) with the bulk of the carbon partitioning into magnesite and that very little remains in solution

Flow pattern, pressure drop and inclination analysis on liquid-liquid two phase flow of waxy crude oil in pipelines using PIPESIM

Produced water is a water that comes out with the crude oil during the production of the well. It contains non-soluble and soluble oil or organics, dissolved and suspended solids with different chemicals used during production process. Thus, it must be properly accounted as it affects the economical productivity of crude oil and separation efficiency as a result of stubborn emulsions between crude oil and water. Thus, a simulation study was conducted using PIPESIM to predict the flow pattern and pressure drop of waxy crude oil and water flow in horizontal and inclined pipelines (i.e., -15° from horizontal). In this simulation study, water cuts were ranging from 0% to 90% while the flow rates were ranging from 2.03 to 16.21 cm3/s. The study comprised fluid modelling, physical modelling and running the simulation with the most suitable multiphase flow correlation in PIPESIM. This simulation study used the waxy crude oil has 16.15% of wax content and simulation was performed at 30°C. The validity of the simulation results was accomplished by comparing the published findings. There were only two types of flow patterns that can be identified by PIPESIM; stratified wavy and dispersed flow. The investigations proved that pressure drop was greatly influenced by flow rates and flow patterns. By decreasing the inclination angle, the boundary between the stratified and dispersed flow regimes shifted to the upper left of the flow pattern map while showing a higher pressure drop than horizontal pipeline due to the combined effect of pressure difference and gravity. The simulation results can be used as a platform for better understanding on more complex cases of gas, oil and water concurrent flow in pipelines

Treated Rhizophora mucronata tannin as a corrosion inhibitor in chloride solution

Treated Rhizopora mucronata tannin (RMT) as a corrosion inhibitor for carbon steel and copper in oil and gas facilities was investigated. Corrosion rate of carbon-steel and copper in 3wt% NaCl solution by RMT was studied using chemical (weight loss method) and spectroscopic (FTIR) techniques at various temperatures in the ranges of 26–90C. The weight loss data was compared to the electrochemical by the application of Faraday’s law for the conversion of corrosion rate data from one system to another. The inhibitive efficiency of RMT was compared with commercial inhibitor sodium benzotriazole (BTA-S). The best concentration of RMT was 20% (w/v), increase in concentration of RMT decreased the corrosion rate and increased the inhibitive efficiency. Increase in temperature increased the corrosion rate and decreased the inhibitive efficiency but, the rate of corrosion was mild with RMT. The FTIR result shows the presence of hydroxyl group, aromatic group, esters and the substituted benzene group indicating the purity of the tannin. The trend of RMT was similar to that of BTA-S, but its inhibitive efficiency for carbon-steel was poor (6%) compared to RMT (59%). BTA-S was efficient for copper (76%) compared to RMT (74%) at 40% (w/v) and 20% (w/v) concentration respectively. RMT was efficient even at low concentration therefore, the use of RMT as a cost effective and environmentally friendly corrosion inhibiting agent for carbon steel and copper is herein proposed

підручник

Міграційне право України: підручник / [ Гусаров С. М., Безпалова О. І., Грохольський В. Л. та інш.], за заг. ред. В.В. Ковальської; МОН України, Міжнар. ун-т бізнесу і права. – Херсон: ФОП Грінь, 2016 – 476 с. – ISBN 978-966-930-098-0.У підручнику викладені основні принципи міграційного права України як самостійної галузі права. У ньому розкрито понятійний апарат міграційного права, проблеми управління міграційними процесами, статус суб'єктів міграційного права, сутність міграційного режиму, принципи відповідальності за міграційні правопорушення. Для студентів, курсантів, аспірантів, ад'юнктів, докторантів, викладачів юридичних спеціальностей вищих навчальних закладів та працівників правоохоронних органів України.The textbook sets out the basic principles of migration law in Ukraine as an independent branch of law. It discloses the conceptual apparatus of migration law, the problems of managing migration processes, the status of subjects of migration law, the essence of the migration regime, principles of responsibility for migration offenses. For students, cadets, graduate students, adjuncts, doctoral students, teachers of legal specialties of higher educational institutions and law enforcement officers of Ukraine.В учебнике изложены основные принципы миграционного права Украины как самостоятельной отрасли права. В нем раскрыты понятийный аппарат миграционного права, проблемы управления миграционными процессами, статус субъектов миграционного права, сущность миграционного режима, принципы ответственности за миграционные правонарушения. Для студентов, курсантов, аспирантов, адъюнктов, докторантов, преподавателей юридических специальностей высших учебных заведений и работников правоохранительных органов Украины

Potential of anionic-nonionic surfactant mixtures for oilwell contaminated drillcuttings washing

Surfactant-enhanced washing is being considered with increasing frequency to achieve contaminant removal. However, sorption of nonionic surfactants by soil surfaces such as clay minerals and/or organic matter content and abstraction of anionic surfactant by multivalent cations may negate their contaminant extraction efficiency. In this research anionic (SDS), nonionic (TX100) and their mixtures (1:1, 1:2, 2:1; TX100:SDS volumetric ratios) were evaluated for the washing enhancement of oilwell contaminated drillcuttings. Evaluation of surfactants are based on examining the ability of the surfactant to maintain lower surface tensions (ST), lower interfacial tensions (IFT) between Sarapar l47 and water, satisfying lower critical micelle concentrations (CMCs), and sustaining lower sorption to drillcuttings. Interaction between binary surfactant mixtures were studied by surface and interfacial tensions. The composition of mixed micelles and the interaction parameter, β evaluated from the CMC data obtained by both surface and interfacial tensions for different systems using Rubingh’s theory were discussed. Using IFTs to determine CMCs before and after equilibration with shale (drillcuttings surrogate) gave different results than using ST technique. Considering ST technique, it has been concluded that presence of SDS do not reduce sorption of TX 100 to shale and that the binary mixtures of SDS and TX 100 do not show any synergism. However, IFT technique measurements allow opposite conclusions, i.e., sorption of TX 100 was significantly reduced by addition of SDS at all molar ratios used in this study. Furthermore, SDS: TX100 mixtures showed a strong synergism particularly in CMCs. The estimated interaction parameters indicate an overall attractive interaction in the mixed micelles

Potential of surfactant washing to solve drilling waste environmental problems offshore

Offshore direct discharge is a simple and economically feasible method in which the contaminated drill cuttings are released to the environment onsite. Recently, disposal of oily drilling waste is strictly regulated. Allowable oil on cuttings particularly offshore is set at limits far difficult for current cleaning technologies to deal with. Therefore there is an urgent need to develop cost-effective methods for cleaning oilwell contaminated drill cuttings and grant their direct discharge offshore. Surfactant-enhanced washing is being considered with increasing frequency to actually achieve contaminant removal. This paper reviews most important factors affecting contaminant removal by surfactants. It has been shown that enhanced surfactant washing normally occurred at surfactant concentrations below and above the CMC indicating the occurrence of both oil drop rollup and/or snapoff and solubilization mechanisms. The later mechanism is greatly enhanced with lower CMC surfactants and the first mechanism with surfactants possessing lower interfacial tensions. In certain cases the lower CMC of nonionic surfactants made them attractive candidates while in other cases the lower sorption and higher solubilization potential of selected anionic surfactants made them the preferred choice. Evaluation of surfactants are based on examining the ability of the surfactant to maintain lower interfacial tension between target contaminant and water, satisfying lower CMCs, and sustaining lower sorption and precipitation to target substrate. Surfactant mixtures of anionic and nonionic surfactant are shown to be excellent candidates for robust surfactant cleaners

Transport properties of slurries in simulated fracture channels

This paper presents the results of a laboratory study of the transport properties of simulated ground drilling waste slurries in vertical channels. The effects of variables such as bulk velocity, solids concentration, particle size, fluid rheological properties and fracture width are presented. The most significant variable are particle size and fluid rheological properties. Bulk velocity and solids concentration were moderately influential and slot width was found to be the less significant

The utilization of Malaysian local bentonite as an extender and free water controller in oil-well cement technology

This paper presents the result of experimental studies for Malaysian bentonite from Sabah (Lahad Datu and Tawau areas) application in oil-well cementing as compared to world wide commercially used Wyoming bentonite of USA. Samples were dried, grounded and sieved into particle size of 75μm. The experiments include XRD & XRF techniques to determine the chemical compositions and mineralogical contentc of bentonite. Methylene blue tests were carried out to estimate the value of cation exchange capacity (CEC) in order to determine the approximate montmorillonite content. In the cement performance tests, class-G cement slurry mixed with bentonite in the range of 2%-6% BWOC. The cement slurries were tested in accordance of API Specification 10. Dry and wet treatment processes were also conducted for the Malaysian bentonite to upgrade its performance. From laboratory investigations, it showed that Malaysian bentonite has less content of montmorillonite mineral and more impurity materials such as quartz, kaolinite, illite, muscovite and hematite, while Wyoming bentonite considered as high-quality bentonite. Malaysian bentonite has low values of CEC which had been improved after treatment processes. Malaysian bentonite has low degree of swelling. The free water of the cement slurry increased with the increase of bentonite concentrations as compared to Wyoming bentonite. On the other hand, after treatment processes, the free water decreases in the cement slurry with bentonite concentrations increased. The Lahad Datu's bentonite had lowered slurry density after the treatments than the Tawau's bentonite

Micellization and synergistic effect in an aqueous solution of an AOS-TX100 mixture: before and after equilibrium in the presence of clay

In this research, a novel surfactant mixture consisting of anionic (alpha olefin sulfonate [AOS]) and nonionic (TX100) type was developed. Possible synergistic effect in micelle formation in different mass ratios of the mixture (1:2, 1:1, and 2:1) was studied by surface tension measurement method. Rubingh's Regular Solution theory was used to evaluate the interaction parameters (β) and activity coefficient (f) for both binary mixture and single surfactants, before and after equilibrium in the presence of clay minerals (kaolinite and illite). The differences between experimentally obtained CMC values and ideally calculated values, showed nonideality of the mixtures. In addition, the lower CMC values of mixtures in comparison with individual surfactants were an indication of synergism. The synergistic effect was maintained before and after equilibrium with clay minerals. The β values of the mixture before equilibrium were in the range -1.5 to -2.6. However, after equilibrium with kaolinite, the values were in the range of -1.9 to -3.9 while after equilibrium with illite they were in the range -1 to -3. For the mixture, before and after equilibrium, the synergism became more severe as mole fractions of AOS increased in the mixture