Bottle Test Method Research Articles

MPEG grafted quaternized carboxymethyl chitosan for demulsification of crude oil emulsions

ABSTRACTFour novel environmentally friendly and highly branched crude oil demulsifiers were prepared by using different molecular weight (Mn = 350, 750, 1000, 1900 g/mol) of methoxy poly(ethylene glycol) to modify quaternized N,O‐carboxymethyl chitosan. Fourier transform infrared and 1H‐nuclear magnetic resonance were employed to confirm the structure of the demulsifiers. The surface tension of demulsifies was determined and hydrophile–lipophile balance value was calculated at the critical micelle concentration. The demulsification performance was evaluated by the bottle test method against water‐in‐oil emulsions simulated in the laboratory and it was found that the dehydration rate of four demulsifiers can come to 74.2%–80.4%, which have better demulsification performance than the commercial demulsifier JL‐1. Demulsification mechanism was discussed, and it was encouraging to find that the tiny water droplets in the emulsion coalesced to form the water phase and separated with the water from the polarization microscope. Results show that methoxy poly(ethylene glycol) grafted quaternized carboxymethyl chitosan has a promising application as a demulsifiers for dealing with W/O crude oil emulsions. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45867.

Population Balance Equation Modeling of Crude Oil Demulsification Considering Demulsifier: Modification of Collision Frequency Function Based on Thermodynamic Model

A theoretical model is developed to consider the effect of demulsifier agent on demulsification of water-in-crude oil emulsion. A thermodynamic approach is considered to correlate the critical micelle concentration of a demulsifier to the collision frequency function in population balance equation (PBE). Based on the proposed correlation, the collision frequency function is modified to account the effect of demulsifier agent on water droplets coalescence. The water separation capability of a selected group of demulsifiers is investigated via the conventional bottle test method to obtain the adjustable parameter of the developed equation so that the absolute relative error of predicted demulsification efficiency and experimental data are considered as objective. Comparison between the model simulated results and the experimental data showed that the proposed model could appropriately reproduce the experimental data at different agent concentrations.

A study of the effects of phenolic de-emulsifier solutions in xylene on the de-emulsification of a Nigerian crude oil emulsion

Abstract The research and development of de-emulsifiers for separating water from crude oil emulsions usually result in varying degrees of success, depending on the location and the type of crude being treated. This makes de-emulsifiers crude oil specific and thus gives rise to the continuous search for more and effective de-emulsifiers that can meet the specific needs of each locality. In this study, base-catalyzed phenol formaldehyde resins were formulated at varying formaldehyde to phenol ratios (1.2:1–1.8:1); the assessment was carried out by the bottle test method at varied de-emulsifier concentrations (vol/vol) in xylene acting as solvent diluent. The bottle test was carried out at an optimum temperature of 70 °C, dosage of 50 ppm and residence times of 10 and 20 min. A factorial design was done to determine the best combination of the de-emulsification conditions for the resolution of the Nigerian crude oil emulsion. The results were analyzed and optimized using Minitab 16 utilizing a Pareto chart, normal effects, main effects and interaction plots. From the analysis carried out, it was found that the most effective formulated de-emulsifier was obtained at formaldehyde to phenol (F:P) mole ratio of 1.8:1, 80% de-emulsifier concentration in xylene and residence time of 20 min. This de-emulsifier obtained a water separation efficiency of 79% compared to the commercial de-emulsifier which gave 71% efficiency. Thus the solution of P:F de-emulsifiers in xylene enhances the de-emulsification of the Nigerian crude oil emulsions.

Effect of intermediate wettability nanoparticles on oil-water emulsion stability

Emulsions are ubiquitous in oil production operations and in general undesirable for various reasons. These include increased pressure losses leading to reduced oil productivity, pipeline and other equipment corrosion, as well as separation difficulties resulting in increased production costs. Surface active agents (also known as surfactants, like asphaltenes, resins, etc.) and solid particles (for example clays) are naturally present in crude oils. These components can act as stabilizers for oil and water emulsions. Therefore in order to mitigate the aforementioned problems related to emulsions, a better understanding of how emulsions are formed and stabilized is essential. This study focuses on nanoparticle stabilized emulsions and aims to contribute to a deeper understanding as it pertains to the effect of solid nanoparticles on the stability of oil and water emulsions.More specifically, the objective of this research is to investigate the separation kinetics of oil-water emulsions stabilized by spherical silica nanoparticles of intermediate wettability and its dependence on solid particle concentration, initial dispersion phase, water-cut, and shearing time. A novel, state-of-the-art, Portable Dispersion Characterization Rig (P-DCR) is used to run the experiments (as compared to the conventional bottle test method) and the relevant software for accurate data acquisition. All tests are conducted at ambient pressure and temperature conditions. Mineral oil and distilled water are used as the test fluids. The initial oil to water ratio in the batch separator is an important parameter. Therefore a broad range of water-cuts is tested. Starting with a 25% water-cut the experimental results indicate that in most cases no emulsion forms and complete phase separation takes place fast. However, when the water-cut increases to 50% and 75% a stable emulsion rag layer phase is always formed and full separation is not achieved within the experimental time frame. For the stirring times examined, faster separation takes place when the nanoparticles are initially dispersed in the oil phase. Using the specific type of nanoparticles, the formation of multiple emulsions (oil in water in oil, O/W/O) is observed. In general, as the nanoparticle concentration increases the rate of the separation process decreases. The size of the solid nanoparticles is also a critical factor and although not studied intentionally, it is inferred from the results that larger particles do not stabilize the formed emulsions as efficiently as smaller particles do.

Demulsifier performance at low temperature in a low permeability reservoir

ABSTRACTThe crude oil in Longdong area is produced in the form of emulsion containing associated oil and water, which needs to be separated before dispatch to end user. Chemical demulsification under high temperature is the most widely used technology to break the emulsions. In this study a rheological method was used to determine the curve of viscosity-temperature and lower limit of temperature was determined. A series of experiments on low-temperature commercial demulsifies were implemented for studying demulsification performance by bottle test method. Mechanism of low-temperature demulsifier was studied by using spinning drop interfacial tensiometer to determine interfacial tension between the crude oil and demulsifier solution by considering the concentration. Turbiscan stability analyzer was used to study the effect of water content, temperature, and demulsifier concentration on emulsion stability. The corresponding relationship between interfacial tension and demulsification was verified through the study of low-temperature demulsifier effect on interfacial tension. Efficient low-temperature demulsifiers AR102, AR901, PR929, and PRC06 were selected. PRC06 was chosen to be the best at 40°C, and when the optimal concentration was 200 mg/L, dehydration rate was 99.51%.

Water distribution network quality model calibration: a case study – Ahar

In water distribution network calibration of quality models, bulk and wall decay coefficients are considered to be the adjustable parameters. The bulk decay coefficient is usually gained by using a laboratory bottle test method, but the wall decay coefficient is calibrated with field data of residual chlorine at nodes. This paper aims to present a method to adjust the wall decay coefficients of pipes. A metamodelling approach is developed by the combination of an Ant Colony Optimization (ACO) algorithm and an artificial neural network (ANN) with the EPANET simulator. The proposed method is applied on a two-loop test example and real water distribution network. Results showed that the proposed method can increase the speed of solution 58 times more rapidly than the simple method in the two-loop network. In the real network, the classification based on the average flow velocity produced the best results among all categories, and the classification based on material, diameter, and age of pipes produced the best results among the physical criteria. Also, comparison of results between the measured and calculated data for testing data showed an average error of 3.85% and the calibration model gave good performance.

Preparation, Characterization and Coreflood Investigation of Polyacrylamide/Clay Nanocomposite Hydrogel System for Enhanced Oil Recovery

ABSTRACTThe synthesis and characterization of polyacrylamide/clay nanocomposites for the development of hydrogel system used in enhanced oil recovery is described. The synthesized nanocomposite copolymer was crosslinked with Chromium (III) acetate to form the hydrogel which exhibited an acceptable gel strength, gelation time and gel stability. The nanocomposite gels prepared with low crosslinker concentration (2000 ppm chromium acetate) showed higher gel strength and required longer gelation time than the conventional polyacrylamide (PAAm) gel; these are desirable properties for the effective placement of gel during enhanced oil recovery operations. The effects of various parameters, such as polymer and crosslinker concentration, on the gelation time and gel strength were evaluated using the bottle testing method. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM) revealed the formation of intercalated and exfoliated clay morphologies. The effects of the clay content on the thermal stability and gel strength of the gel network were also investigated by thermogravimetric analysis (TGA) and rheological measurements (oscillatory time sweep profiles), respectively. Also, in-situ gelation and core flooding experiments revealed that a significant permeability reduction of the sand pack cores could be achieved at reservoir conditions when they were treated with the developed nanocomposite gel formulation. Hence, this nanocomposite gel system with low crosslinker concentration (10,000 ppm of nanocomposite polymer concentration containing 2000 ppm of clay with 2000 ppm chromium acetate crosslinker) may be suitable in water shut-off treatments required for enhanced oil recovery from the oil fields.

Demulsification of water in oil emulsion using ionic liquids: Statistical modeling and optimization

In this research, the performance of three ionic liquids namely Trioctylmethylammonium chloride, Trioctylmethylammonium bromide and 1-Hexadecyltrimethylammonium bromide are evaluated as the demulsifier agents to break crude oil emulsion through the bottle test method. Then, the response surface method (RSM) is applied to investigate the effect of demulsifier concentration, temperature, pH and fresh water ratio on the dehydration efficiency of the prepared agents. The experiments are designed based on the central composite design method (CCD). To find the optimum conditions of input variables, an accurate model is developed to predict the dehydration efficiency of agents based on the statistical testing of various models by the analysis of variance (ANOVA). The results shows that temperature and pH of aqueous phase are two main parameters in the demulsification process and the maximum dehydration is attained at neutral value of pH and nearly the maximum temperature in the all samples. Then, the optimum operating conditions of agents are determined by RSM.

Optimization of Phenolic Based De-Emulsifiers

The de-emulsification of a Nigerian crude oil emulsion has been investigated using locally formulated base and acid catalyzed phenol formaldehyde resins with varied formaldehyde to phenol molar ratios. The bottle test method was used for the screening process and the best de-emulsifier was chosen based on the largest volume of water removed from the crude oil emulsion. The screening process was done at temperatures of 50 and 70°C and de-emulsifier concentrations of 20 and 50 part per million (ppm), respectively. A factorial design was done to determine the best combination of de-emulsification conditions for optimal performance. The results were optimized and analyzed using software called Minitab 16 utilizing pareto chart, normal effects, main effects and interactions plots. From the analysis, it was found that the optimum set of conditions for best performance of the resole de-emulsifier were 50 ppm, 70°C and 1.8:1 concentration, screening temperature and formaldehyde to phenol molar ratio, respectively. While for novolak de-emulsifiers, they were 50 ppm, 70°C and 0.1:1. Increasing temperature and concentrations were found to enhance de-emulsification performance with all the resole and novolak de-emulsifiers.

OPTIMIZATION OF DEMULSIFIER FORMULATION FOR SEPARATION OF WATER FROM CRUDE OIL EMULSIONS

In this study, various water-soluble and oil-soluble demulsifiers were selected for separation of water from crude oil emulsions and their productivity measured using the Bottle-test method at 70 °C and 10 ppm concentration. The best ones among 23 demulsifiers examined through the screening process were fatty alcohol ethoxylate, triethanol amine and urea from the water-soluble group and Basororol E2032, Basorol PDB 9935 and TOMAC from the oil-soluble category. Furthermore, the present study investigated the factors effective for demulsification such as temperature, concentration, pH, salinity and modifiers. It was found that the separation improves with increasing demulsifier concentration, increasing salt content, increasing temperature up to 80 °C, keeping the pH values between 5-9. Adding solvent modifiers proved unnecessary. Two formulations were prepared based on suggested optimal concentrations of demulsifier content by experimental design using Qualitec 4 and these proved to be highly effective in treating real and synthetic emulsions.

Efficient demulsification of water-in-oil emulsion by a novel nano-titania modified chemical demulsifier

The exploration and production of crude oil are often accompanied by water in oil emulsion (W/O) formation that can pose serious problems for downstream refinery industries. Chemical demulsification and electrostatic separation are two major techniques that are commonly used to overcome the problems associated with the formation of W/O emulsions. In this study, nano-technology was employed to facilitate the demulsification process and titania was chosen as a case study. A wide variety of nano-titania particles were synthesized by sol–gel method. The prepared samples were dispersed in a conventional chemical demulsifier to verify whether it can improve the separation process. The prepared nano-titania particles were analyzed by particle size analysis (PSA), X-ray diffraction (XRD), transmission electron microscopy (TEM), bottle test, electrostatic test, and standard IP77 method. The results specified the sample with the highest water separation performance and obviously revealed that it would effectively increase the demulsification efficiency to a value greater than 90% and it would also decrease the settling time required for efficient separation.

Investigating the Effect of Several Parameters on the Gelation Behavior of Partially Hydrolyzed Polyacrylamide–Hexamine–Hydroquinone Gels

The polymer gel systems are mostly used for the control of excessive water production during enhanced oil recovery operations in mature oil fields. However, these polymer gels are not stable in the high-temperature and high-salinity reservoir. Keeping these in mind, an attempt was made to investigate the effect of several parameters on the gelation time of polymer gels for its suitable application in the oil fields. In this paper, a polymer gel comprised of partially hydrolyzed polyacrylamide as a water-soluble polymer and hydroquinone and hexamine as organic cross-linking agents of low toxicity was prepared to control excessive water production. The effect of various parameters such as polymer and cross-linker concentrations, temperature, pH, and salinity on the gelation time and gel strength was evaluated using the bottle testing method, and variations in the performance of the polymer system were analyzed under different gel compositions and environmental conditions.

Study on Demulsification of a Demulsifier at Low Temperature and Its Field Application

The demulsification performance of a demulsifier at low temperature has been investigated. Bottle testing method was used to study the effect of water content, temperature, and demulsifier concentration on the demulsification performance. Interfacial rheological method was used to understand the demulsification mechanisms. Finally, a field test was carried out using the demulsifier in an oil-water treatment centre of Fuyu oilfield. It was found that this demulsifier has excellent demulsification performance when its concentration is about 100 mg/L and the demulsification temperature can be reduced by more than 15°C. This technology can be used to greatly reduce the energy consumption, and thus to reduce the production cost.

Performance evaluation of formulated de-emulsifier samples and a commercially available sample in the de-emulsification of a Nigerian crude oil emulsion

The de-emulsification of water-in-oil emulsion of Ogharefe crude oil sample was studied by using formulated polyester based de-emulsifier sample A and a commercially available de-emulsifier sample C. The bottle test method was used to screen the de-emulsifier samples using the crude oil emulsion. The performance of the de-emulsifiers was expressed in terms of percentage of water separated from 100 ml samples of emulsions. For both the formulated and commercial deemulsifiers, the performance increased with increased concentration of the de-emulsifiers, separation time and operating temperature. The effect of the operating temperature was much higher and there was a linear relationship (R2 ranging from 0.96 to 0.99) between performance and temperature.The performance of the best of the formulated de-emulsifiers, sample A, was better than that of the commercial de-emulsifier under all the conditions of this study- the volume of water expelled by sample A was 5 times that of the commercial one at 30oC. At 70oC, this ratio increased to 14.

Synthesis, Surface‐Active Properties, and Emulsification Efficiency of Trimeric‐Type Nonionic Surfactants Derived From Tris(2‐aminoethyl)amine

AbstractTrimeric‐type nonionic surfactants based on tris(2‐aminoethyl)amine were prepared. N‐alkyl chloride (namely, octanoyl chloride, n‐decanoyl chloride, n‐dodecanoyl chloride) was reacted with tris(2‐aminoethyl)amine in the presence of toluene and triethylamine. The products were partially reduced and then ethoxylated by poly(ethylene glycol) of molecular weights 400, 1,000, and 2,000 g mol−1. The structures were confirmed by infrared (IR) and 1HNMR spectroscopy. The molecular weights of the surfactants were measured by gel permeation chromatography (GPC). The properties of the prepared compounds were investigated by the surface tension, interfacial tension, and cloud point. The emulsification power of the prepared surfactants for oil‐in‐water emulsions was also studied and the emulsion stability was monitored by an optical microscope and the bottle testing method. Some factors affecting the emulsion stability were investigated

Mechanism of stress cracking of poly(ethylene terephthalate) beverage bottles: A method for the prevention of stress cracking based on water hardness

A recently described bottle test method was used to evaluate the dependence of stress crack failure of poly(ethylene terephthalate) (PET) carbonated soft drink bottles on water hardness. Although the industry belief is that water hardness is irrelevant to stress cracking, it was found that hardness ions exert a tremendous positive impact by deactivating water alkalinity through precipitation as harmless carbonate minerals. This mitigating effect of hardness means that no complete understanding of stress cracking as a function of alkalinity is possible without also considering water hardness. A useful concept is that of excess alkalinity, which is defined as alkalinity that is not precipitated during solution evaporation. Limiting excess alkalinity by using water with sufficient hardness is an effective means of stress crack prevention in PET soft drink bottles. Evaluation of compositions which are typical of those used for lubricating PET bottles on production conveyors showed that the role of these compositions in stress cracking was that of spectators, that is, they neither cause failure if water does not otherwise cause it, nor stop failure if water otherwise causes it.

A Case History of Heavy-Oil Separation in Northern Alberta: A Singular Challenge of Demulsifier Optimization and Application

Summary This case history tracks the continual improvement cycle for the fluid-separation process of a heavy-oil/oil-sands production facility in northern Alberta over a period of 3 years. The major challenge posed by the operator of this 13 to 16°API crude oil was to move away from injection of two separate demulsifier formulations to injection of a single product. This was not an easy task because of the very different conditions that existed at the two injection locations. The first location was at a series of injection points upstream of the gathering stations before separation where temperatures could reach subzero conditions, and the second was at the battery receiving facility where heating increased temperatures to 100°C. Water cut and shear were also very different, and the operator required a very strict 0.2% basic sediments and water (BS&W) on the crude exiting any of the four treater tanks. To complicate issues further, crude-oil viscosity ranged from 500 to 5,000 cp. A unique bottle testing method was developed and used to simulate the field conditions as accurately as possible. Details are given on the chemistry of the individual components of the demulsifier determined to be so crucial to adequate performance and how this was optimized in the field after being identified from the bottle tests. Results show how careful consideration was given to the concentration of the demulsifier bases in the blends, and show the curious observation that dilution of the final product made a big difference to the final performance in the field. Elaboration is given on potential mechanisms explaining the dilution effect, and this paper will conclude with observations on how careful design of field testing followed by field implementation can indeed solve complex separation issues and address individual well, battery, and field requirements.

Polyacrylamide Gel Polymer as Water Shut-off System: Preparation and Investigation of Physical and Chemical Properties in One of the Iranian Oil Reservoirs Conditions

In this paper, polyacrylamide/chromium acetate gel polymer system was prepared as water shut-off system to control water production in one of the Iranian oil reservoirs condition. Effect of various parameters such as temperature (90 °C) and water formation from view point of salinity and divalent cations, was evaluated on the gelation kinetic and gel strength using bottle testing method. The results showed that the increase of temperature caused a decrease in the gelation time. Also, presence of divalent cations in formation water, decreased gelation time and by precipitation could cause instability in gel structure.

Modified Centrifuge Technique for Hydrolytic Stability of Neopentyl Polyol Ester Lubricants

Abstract A modification of the ASTM Test for Hydrolytic Stability of Hydraulic Fluids (Beverage Bottle Test Method) [D 2619-67 (1972)] is proposed to permit the application to fluids with specific gravities near to that of water. Data obtained in applying this modification to MIL-L-23699 “Lubricating Oil, Aircraft Turbine Engine, Synthetic Base” are presented.