Journal of Chemical and Petroleum Engineering
Volume:55 Issue: 1, Jun 2021

Using a sulfonated polyacrylamide (SPAM) and Cr3+, a new colloidal dispersion gel (CDG) was prepared. The viscosity of the CDG samples in different crosslinker concentrations and brine compositions was measured. The results showed that CDGs approach a Newtonian-like behavior in high crosslinker concentrations and salinities, signifying that they possess more rigid, less flexible particles that can be used to block some of the pore throats of the high-permeability layers. Therefore, three core flood tests were performed and the retention of the polymers and the final RRF values (residual resistance factor) were determined. Although CDGs showed a lower tendency to be adsorbed onto the rocks, they caused drastically higher RRF values (caused higher permeability reductions). Thus, it can be concluded that CDGs are superior compared to normal polymer solutions in modifying the permeability. Moreover, changing the post-flood fluid from brine to distilled water caused the RRF to decrease, hence a weaker effect on the permeability.

Despite the considerable progress in the safe and effective use of renewable energy, oil is still the world's first choice as an energy source. Meanwhile, after the traditional oil recovery methods, a large quantity of crude oil remains deposited in the oil well. The chemical enhances oil recovery method implies the injection of surfactants to increase oil recovery. The basic principle of surfactant flooding is to decrease the imbalance tension force to increase the mobility ratio of oil. In this study, extensive lab work has been done to identify the synergic effect of surfactant, alkali, and salt on acidic crude oil. The design expert generated the composition of the injection fluid, and the obtained results in terms of viscosity, surface tension, pH, and conductivity are reported in this paper. Also, the optimum point or the concentration combination of surfactant, alkali, and salt generated by the design expert has the maximum effect on the acidic crude oil. A remarkable decline was noticed in the acidic crude and surface tension's viscosity at an optimum point. In contrast, an increase in pH and conductivity of acidic oil was observed. The results reported herein correspond to a significant understanding of the interaction of surfactant-alkali and salt solution with acidic crude and change in the crude oil properties.

In this paper, a mathematical model is developed to calculate the conversion and the residence time reaction for plug flow and mixed flow in the fluidized reactors filled with flat plate particles using the shrinking core model. In this modeling, the size of the particles is unchanged during the reaction. Also, the reaction rate is controlled by the gas layer resistance, the ash layer resistance, and the reaction resistance as well as the combination of them. It is also assumed that the gas diffuses from the side, whereas the effect of diffusion in the axial direction is neglected. Equations are solved by numerical methods. This paper's innovation is investigating the combination of resistances effect on the conversion of the reaction. The results for a specific time show that when the reaction rate is controlled by each of the resistances individually, the conversion rate is greater. For example when the reaction is controlled by the ash layer resistance versus when the other two resistance regimes control it. Finally, the effect of the combination of different controlling regimes on the conversion and residence time of reaction for plug flow and mixed flow of particles is studied and it is found that the overall results are similar to each other. In addition, the results that the curves for the gas film layer resistance and the chemical reaction resistance, are the same and correspond to each other. Because the equations of the conversion rate are the same.

A quantitative structure-property relationship (QSPR) in-silico study was performed to develop a mathematical model that correlates 2D and 3D descriptors of 37 antioxidant lubricant additives (compounds) with their properties. A molecular dynamics simulation study was also carried out to access these additives' binding strength on diamond-like carbon (DLC) and steel crystal surfaces. Five novel antioxidant lubricant additives were designed from the information derived from the QSPR mathematical model’s high coefficient molecular descriptors. All the novel lubricant additive’s antioxidant properties were found to be better than our previous study, with the lubricant additive (Z)-3-(4-(5-amino-1-phenyl-1H-pyrazol-3-yl)-3,5-dimethylphenyl)-2-phenyl-5-(thiophen-2-ylmethylene)-3,5-dihydro-4H-imidazol-4-one found to possessed excellent antioxidant properties of 0.850281 total acid values (T.A.V 0.1g/L) than its co-additives.  Moreover, all the designed additives dynamically bind to steel crystal surfaces excellently from our dynamic simulation study than the DLC crystal surface. The molecular dynamics simulation results were found to be better than the one reported by our previous study. This investigation will help synthesize novel and excellent antioxidant lubricant additives that will hinder the base oil from undergoing a complete oxidation cycle and meet environmental requirements as these novel additives do not contain Zinc and Phosphorus, which often rendered exhaust pipes catalytic converter inactive, thereby increasing environmental pollution.

Water has been recognized as the most fundamental factor in organisms' lives and the most widely used element in industries, while currently, the world is dealing with water scarcity in many areas. This emphasizes the importance of preventing water contamination as well as returning contaminated water produced by industries to the production and consumption cycle. Yet, the need for environmental protection is a certain principle that is generalized in today's world. This necessity has become more important with the growth of industries and technologies and subsequent contamination. Advanced oxidation technology has been substantially developed in recent decades, becoming increasingly important in the treatment process of industrial wastewaters containing resistant organic materials that cannot be removed through conventional treatment methods to reduce water quality parameters. The present study has examined the chemical oxygen demand (COD) in the synthetic monoethyl amine wastewater prepared by the solar Photo-Fenton process. Principal effective parameters in the advanced oxidation technology, including the processing time, the concentration of hydrogen peroxide ion, the concentration of iron (II) ion, and pH, were investigated by the response surface methodology (RSM) through 30 random experiments using central composite design method (CCD) to optimize reaction conditions. The most sufficient operational conditions were achieved at pH=4, [Fe2+] =2 mM, [H2O2] =20 mM, and t=90 min for the COD removal rate of 77.08%.

Effective pretreatment of lignocellulosic biomass could be used to produce fermentable sugar for renewable energy production, which reduces problems related to nonrenewable fuel. Therefore, the purpose of this study was to produce monosaccharide sugar for renewable energy from agricultural waste via ammonia pretreatment optimization using response surface methodology (RSM) and artificial neural network (ANN). Cornstover was collected and mechanically pre-treated. RSM and ANNwere applied for experimental design and optimum parameters estimation. Cornstover was converted into simple sugars with a combination of ammonia treatment subsequently enzymatic hydrolysis.The maximum yield of glucose (87.46%), xylose (77.5%), and total sugar (442.0g/Kg) were all accomplished at 20 min of residence time, 4.0 g/g of ammonia loading, 132.5 0C of temperature, and 0.5 g/g of water loading experimentally. While 86.998% of glucose, 76.789% of xylose, and 439.323(g/Kg) of total sugar were achieved by prediction of the ANN model. It was shown that cornstover has a massive potential sugar for the production of renewable fuel.  Ammonia loading had a highly significant effect on the yield of all sugars compared to other parameters.  Interactively, ammonia loading and residence time had a significant impact on the yield of glucose, while water loading and residence time, had a significant effect on the yield of xylose. The accuracy and prediction of an artificial neural network are better than that of the response surface methodology.

The salt can reason severe difficulties like fouling, corrosion using salt deposition, and catalyst poisoning in the downstream parts. This study presents a modification process for improving the efficiency of dehydration in a desalting unit. The main purpose of this investigation is to substitute the mixing valve with an electrical mixing system. Process configuration was modeled in addition to the electrostatic desalting drum. Based on this model, it is affirmed that modification is capable to increase the efficiency of dehydration. The models are designed according to the population balance technique to predict water cut in treated crude oil. To improve the considered model accuracy, the consequences are compared to industrial data of the mixing valve. The comparison between the results gained by the mixing valve and the electric mixing system proves the superiority of the suggested tool. Furthermore, the results indicate the electric field strength optimum value in the mixing step to attaining minimum water cut in treated crude oil.

It was shown that the concept of drag-reducing in the pipe flow with the aid of macromolecules is of great importance in practical engineering applications. In this study, the drag-reducing the performance of three biological macromolecules including guar gum (GG), xanthan gum (XG), and carboxymethyl cellulose (CMC) was compared with three synthetic macromolecules including polyethylene oxide (PEO), polyacrylamide (PAM), and polyacrylic acid (PAA). Results showed that all the macromolecules enhanced the DR% except for GG. DR% for almost all of the macromolecules deteriorated with increasing fluid flow rate. On the other hand, DR% enhanced with increasing the pipe diameter for the synthetic polymers but this effect is not obvious for biological polymeric solutions. Maximum DR was 44%, which occur at 1000 ppm concentration of XG at 30 °C and flow rate of 6 l/min and diameter ½ inch. Finally, a new correlation was developed for the prediction of friction coefficient based on the Prandtl-Karman relation with the newly adjusted slope which is a linear function of polymer concentration. This correlation was in excellent agreement with the experimental data.

The efficiency of an antifoam consists of polydimethylsiloxane oil, hydrophobe silica particles, and either Sodium Dodecyl Sulfate (SDS) as an anionic surfactant, or Octyl phenyl deca ethylene oxide (Triton X-100) as nonionic surfactant for use in aqueous system is investigated. The performance of different combinations of oil, silica particles, and surfactant in control of foam height was determined using Bickerman Shaking test. The effect of surfactant in reducing the surface tension was determined using Wilhelmy test. The sizes of dispersed oil droplets and silica particles were determined using both optical and electronic microscopy. It was found that increasing the silica content of the antifoam mixture and using sharp-edged particles increase the performance of antifoam and decrease the foam disappearance time. This Observation was the same for both cases of using anionic and nonionic surfactants. It was also found that, as the inert gas purging rate increases, the time of deactivation decreases to less than a minute; a favorable performance for good quality antifoam.

Unwanted production of water in oil and gas reservoirs due to water coning is one of the headaches of the petroleum industry. Despite mechanical methods, some chemicals are also developed to delay or prevent this problem. Polymer gels have been proved to be a reliable and economical solution for water production. In this paper, we present a summary of tests for three different gel systems for a pre-determined reservoir condition. A metallic crosslinker (Chromium(III) Acetate), a polymeric crosslinker (Polyethylenimine), and an organic crosslinker mixture (Hexamethyleneteramine + Hydroquinone) are used for crosslinking HPAM polymer. The tests are performed for different concentrations of polymer and cross-linker. Gel strength and stability of these polymer gels are recorded over six weeks. The apparent viscosity of these gels is recoded and compared. The impact of salinity on gel strength and stability is also investigated. The results show that for the determined reservoir conditions HPAM-Chromium(III) Acetate and HPAM-Hexamethyleneteramine-Hydroquinone gels could form a stable and rigid barrier against water.

The ability to approximate the nanofluid properties such as viscosity, thermal conductivity, and specific heat capacity will greatly assist in the modeling and design of nanofluidic systems. The purpose of this study was to present an adaptive neuro-fuzzy inference system (ANFIS) model for estimating the viscosity of Water/Glycerin nanofluid-containing Cu nanoparticles. The model inputs consist of two variables of temperature and volume concentration of nanofluids which have a great influence on the nanofluid viscosity. The experimental data were divided into two categories: training (three-quarters) and testing (a quarter of the data). The grid partition and subtractive clustering approaches were employed to determine the ANFIS configuration. The mean value of the relative error of 5.18% and the root mean square error of 0.0794 were obtained by comparing the target and model output values for the testing data. Proper matching of ANFIS prediction results with the test data set indicates the validity of the model. In addition, an empirical correlation was developed based on the form presented in the literature. The constants of the equation were determined by the genetic algorithm (GA) searching technique. The comparison of the prediction accuracy of the two models showed the complete superiority of the ANFIS.

In this study, a nano-layer polydopamine (PDA) coated superparamagnetic maghemite nanoparticles (MNPs) was applied to investigate the asphaltene adsorption-desorption behavior using a model solution. In this process, Fourier-transform infrared spectrum (FT-IR) spectroscopy of the polydopamine/MNP core/shell (MNP@PDA) before and after asphaltene adsorption was indicated the attachment of asphaltene molecules on the polymeric nano-adsorbent surface. The isotherms and kinetics of the asphaltene adsorption process on the MNP@PDA were studied. The good prediction of asphaltene adsorption by the modified Langmuir model indicated that adsorption occurs on an MNP@PDA surface by multilayer adsorption. Also, within the kinetic models, the double-exponential model can fit the experimental data well. The obtained results revealed that about 90% removal for asphaltene happened within 30 min which can be acceptable. The results of this study showed that natural polymers can be used for surface modification of nanoparticles and use it successfully for asphaltene adsorption from prepared asphaltene-toluene solution.