Oil Mass Research Articles

Numerical optimization of guaco leaves extraction based on pre‐heat treatment

AbstractThe mass yield of the extraction is influenced directly by the pre‐treatment conditions of the raw material. In the case of leaves, drying is required to ensure their biological stability and is a pre‐processing step that demands large amounts of thermal energy. In the present study, the oil extraction process was numerically optimized, considering the influence of the pre‐heat treatment of the guaco leaves. An operating range between 30°C and 70°C, 1.0 and 5.0 m/s, and recirculation between 0 and 1 was evaluated. The minimum ratio of energy consumption of drying by the amount of oil obtained after extraction (4.05 × 105 kWh/kg) was obtained under the optimal conditions of 30.02°C, 1.0 m/s, and .129 of air recycling flow rate. With our results, it is possible to guarantee safety in the storage of guaco leaves, in addition to optimizing the extraction process, maximizing the obtaining of the oil mass, and reducing energy consumption in the drying step.Practical applicationsTea is one of the most consumed beverages in the world and is obtained by extraction. Between tea leaves, guaco (Mikania glomerata Sprengel) is mainly applied to obtain therapeutic properties as an expectorant and bronchodilator. While guaco leaves are perishable, they must be dried to ensure their biological stability. As others heat and mass transfer processes, the efficient design is mandatory to reduce energy consumption. One of the more efficient drying processes is the operation under exhaust air recirculation. Thus, there is a need to evaluate optimal drying operation conditions to understand the effects of exhaust air recirculation on the energy consumption of drying and the amount of extract obtained in the extraction. Our numerical results indicated that it is possible to guarantee safety in storing guaco leaves and optimize its extraction process.

Biodiesel Synthesis from Coconut Oil Using Calcined Scallop Shell Waste as the Heterogeneous Catalysts

Several efforts have been performed to make the biodiesel price more competitive with fossil fuels, such as using low price raw materials, including coconut oil and the use of heterogenous catalyst. In this research, the Calcined Scallop Shell was applied as a heterogeneous catalyst for synthesizing biodiesel from coconut oil. The catalyst was obtained from calcination of scallop shell waste. The catalytic activities of Calcined Scallop Shell catalyst during transesterification reaction was influenced by several reaction conditions including methanol to oil mole ratio, reaction temperature, and concentration of catalyst. The biodiesel yield of 91.7% was obtained at a methanol to coconut oil mass ratio of 12:1, 60 °C reaction temperature, and catalyst concentration of 10% wt. of oil.

Optimization and analysis of bioenergy production using machine learning modeling: Multi-layer perceptron, Gaussian processes regression, K-nearest neighbors, and Artificial neural network models

Since fossil fuels are slowly depleting, bio and renewable energies are now given more attention. The main purpose of this research is to investigate and optimize the influencing parameters of bioenergy production through transesterification process. The application of artificial intelligence (AI) in bioenergy production studies has become increasingly popular due to its capability of interpreting nonlinear relationships between inputs and outputs for complex systems. Here, after conducting library studies and carefully reviewing the existing methods, the multi-layer perceptron (MLP), K-nearest neighbors (KNN), Artificial neural network (ANN), and Gaussian processes regression (GPR) models were selected for simulation and prediction of the efficiency of fatty acid methyl ester (FAME) production. The main effective transesterification parameters on production of biodiesel including the temperature of reaction (°C), catalyst mass to oil mass ratio (wt.%), and the molar ratio of methanol to oil were set as the input variables in all studied models. For reaction between oil and short chain alcohols, wollastonite (a calcium metasilicate, CaSiO3) was utilized as a phase boundary catalyst. By carefully selecting the execution conditions of the algorithms in the model selection phase, all three models reached a result above 0.99 and close to 1 with the square R criterion. Also, the RMSE values for the studied models were 3.95 for MLP, 1.09 for KNN, 0.13 for ANN and 3.60 for GPR models. Therefore, it can be concluded that although the ANN model was to be a better model in process efficiency prediction in terms of error, but all three algorithms had high accuracy because of different generality types. The optimum yield of 97.8% for FAME production was observed at optimum methanol to oil molar ratio, reaction temperature, and catalyst mass to oil mass ratio 65°C, 15, and 9.21 wt%, respectively.

Separation of m-cresol from model oil by pyridinium-based ionic liquids: COSMO-RS screening, experimental study, and process simulation

The separation of phenolic compounds from low-temperature coal tar is conducive to the rational utilization of resources and environmental protection. In this work, pyridinium-based ionic liquids (ILs) were used as extractants for m-cresol/cumene separation. 70 pyridinium-based ILs formed by 10 cations and 7 anions were screened combining the calculation of the extraction ability of ILs for m-cresol and the mutual solubility of ILs with cumene by COSMO-RS model. The influences of cation and anion structures were studied and further explored by σ-profile and σ-potential. Among 70 ILs, the IL 1-ethyl-pyridinium dicyanamide ([C2py][N(CN)2]) was finally identified. Then [C2py][N(CN)2] was synthesized and used to separate m-cresol from model oil. The influences of stirring time, temperature, IL: model oil mass ratio, and initial m-cresol content on the separation performance of [C2py][N(CN)2] were investigated. The regeneration of [C2py][N(CN)2] was carried out and was characterized by FT-IR. The formation of hydrogen bond between [C2py][N(CN)2] and m-cresol was confirmed by FT-IR. Moreover, the process simulation and optimization were investigated by Aspen Plus based on the NRTL model. For the separation process using [C2py][N(CN)2], products with high recovery ratio (99.97% for m-cresol and 99.99% for cumene) and high mass purity (99.97 wt% for m-cresol and 99.80 wt% for cumene) were obtained. The simulation results could provide a guidance for industrial application.

Biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing

A solid catalyst was prepared from waste filter cake (WFC) from a sugar beet processing plant and used, after calcination at 900 °C within 2 h, for biodiesel production from rapeseed oil and methanol. The calcined WFC (CFC) catalyst was characterized by XRF, FTIR, XRD, TGA/DTG, TPDe, TPD-CO2, SEM, N2 physisorption, and Hg porosimetry. The CFC is a CaO-based catalyst with a rigid, sustainable macroporous structure with the largest particles of 2.0 × 0.5 µm, a specific surface area of 7.3 m2/g, and a basicity of 0.27 mmol/g. It provides high conversion of 97.9% in 1 h at the methanol-to-oil molar ratio of 9:1, the temperature of 60 °C, and the catalyst loading of 10% of the oil mass. Its catalytic efficiency is comparable to the WFC-based nanocatalysts and CaO-based catalysts from natural sources. CFC was reused twice with a negligible decrease in catalytic activity, ensuring a FAME content above 97% in 1 h. The biodiesel produced from rapeseed oil over the CFC catalyst has good fuel properties that fulfill most of EN 14214. Therefore, WFC is a promising source of a low-cost, highly active, basic, and environmentally friendly CFC catalyst, which could reduce biodiesel production costs. From this point of view, this catalyst has great potential for developing the process at the commercial level.

Simulation separation of triglycerides from Calophyllum inophyllum oil with continuous countercurrent extraction process using Aspen HYSYS

The trends of industry 4.0 transform a process design to a cost-effective development with digital simulation. The objective of this study was to simulate the separation and purification of triglycerides from crude Calophyllum inophyllum oil with a continuous countercurrent extraction method using Aspen HYSYS V.11 to find the appropriate binary parameter coefficients and predict the optimal conditions. It is expected that the oil’s purity suitable with the edible oil standards (minimum 96% triglycerides and 0.3% free fatty acids). The variables used are the flow rate (n-hexane + oil) to methanol and the total mass ratio of solvent to oil. The C. inophyllum oil used contains 63.91% triglycerides, 15.76% free fatty acids, 12.25% diglycerides, and 4.66% monoglycerides. It was evaluated by applying NRTL (Non-Random Two Liquid) and UNIQUAC (Universal Quasi Chemical) fluid packages with binary interaction parameters of UNIFAC-VLE, UNIFAC-LLE, Immiscible, and Modified (fitting parameters). The most suitable fluid package and binary interaction parameter pairing was achieved by combining NRTL fluid package with Modified binary interaction. The highest purity of triglycerides was 92.86%alongside a simulation error of 0.01% while the free fatty acid was 2.17% and 0.91%, respectively, at solvents (hexane and methanol) to oil mass ratio of 6:1 with a hexane-oil to methanol flow rate ratio of 6:15 (LPH/LPH). By upscaling the n number in the extractor, this model can predict the best result of separation and purification of triglycerides with the highest purity of triglycerides and free fatty acids were 96.736% and 0,0001%, respectively. Thus, the edible oil standards can be met.

Stratification and heat transfer characteristics of partially miscible lubricating oil-refrigerant mixtures during pool boiling

• Partially miscible oil-refrigerant mixture stratifies into four layers at boiling. • Newly proposed nucleate boiling model reflects effects of mixture stratifications. • Bubble dynamics and concentration diffusion determine mass transfer among layers. • Predicted thicknesses of separated layers agree well with observation results. • Mean deviation between predicted and measured heat transfer coefficients is 15.3% Applying partially miscible lubricating oil-refrigerant mixtures instead of completely miscible ones in refrigeration systems is a promising way to avoid the refrigerant insufficiency, and the application of partially miscible oil requires the clarity of nucleate pool boiling characteristics of partially miscible mixtures. As partially miscible mixtures at boiling conditions show an entirely different stratification process compared to completely miscible mixtures or partially miscible mixtures at non-boiling conditions studied by former researchers, the existing researches cannot be directly applied to evaluate pool boiling characteristics of the partially miscible mixture. The purpose of this study is to experimentally investigate and model both stratification and heat transfer performance of nucleate pool boiling of the partially miscible oil-refrigerant mixture. The stratification phenomenon at boiling of partially miscible mixtures is observed, and up to four layers (i.e., an oil-rich micro-layer, a middle oil-poor layer, a top oil-rich layer, and a gas phase layer) are found. The boiling process of partially miscible mixtures stratifying from a single layer into four layers is modelled, and calculation methods of mass transfer rates among layers are proposed. The model validation shows that predicted thicknesses of layers accord with experimental images, which covers the conditions of heat flux ranging from 5 to 15 kW/m 2 , initial oil mass fraction ranging from 5 to 15%, and initial height ranging from 80 to 120 mm. Predicted heat transfer coefficients agree with 80% of the experimental data within the deviation of ± 25%, and the mean deviation is 15.3%.

Adsorption study of oil spill cleanup from sea water using natural sorbent

Lawsonia leaves were used as biodegradable biomass in the oil spill cleanup from seawater. Spilled oil mass, removal time, adsorbent dose, and sorption temperature are the main parameters studied in the oil/water system. At room temperature (28 °C), the optimum oil capacity reached 1.60 g/g at 2 min. Sorption system was modeled by isotherm (Freundlich, Langmuir, Redlich-Peterson) and kinetic (Pseudo-first-order, Pseudo-second-order, Elovich, and Intraparticle) models. Langmuir isotherm appeared best-fitting models with R2: 0.9541 indicating oil sorption monolayer onto Lawsonia leaves. In addition, the results are good fitting with the Pseudo-first-order kinetic model (R2: 0.9732) compared to other models representing the physical sorption of oil onto Lawsonia leaves and the sorption thermodynamic appeared an exothermic sorption system. Furthermore, the reusability of Lawsonia leaves established the economic recycled of biomass up to 4 sorption cycles.

Experimental Characterisation and Field Experience of a Reusable, Modified Polyurethane Foam for the Mechanical Clean-Up of Oil Spills on the Sea Surface

Oil spills at sea, such as the Deepwater Horizon incident in 2010, are devastating environmental hazards, especially for biodiversity in the maritime ecosystem. In order to help the restoration of coastlines, it is critical to clean the oil up quickly and efficiently with various measures, such as the use of barriers, skimmers, sorbents, dispersing agents, in situ burning, and biological agents. However, most of them still cause high remediation costs; are inefficient, non-reusable, and not environmentally friendly; lack a convenient desorption method; or are simply not yet ready to use in a real-case scenario, where high amounts of hydrocarbons must be removed. Therefore, in this work, a reusable modified polyurethane foam for oil absorption on the sea surface is presented and characterised. Due to a chemical formulation with a special co-polymer, its oleophilic properties are strongly enhanced. Laboratory soaking tests with different oils and a mixture of Louisiana sweet crude oil with artificial sea water (ASW) are conducted. To do so, a pneumatic press with adjustable pressures was used to characterise the foam’s capability to recover oil between 10 and 18 times its own weight for a period of up to 50 consecutive repetitions with a maximum saturation in less than one minute. Sequential trials with different oil mass fractions in ASW determined a decreasing content of recovered ASW with increasing amounts of crude oil, while, in all cases, the total oil recovery rate proved to be more than 90% within one’s standard deviation. Finally, practical applications of sorption methods are presented to give an idea of difficulties encountered in real remediation scenarios.

A novel alternative to free oil remediation and recovery: Foamy absorbents designed from low molecular paraffinic waste

This study focuses on preparing porous, hydrophobic, and oleophilic hydrocarbon-based foams applicable for removing free oils from water surfaces. Paraffinic waste material generated during industrial production of low-density polyethylene (Qatar Petrochemical Company) was used for the preparation of foamy, elastic structures through crosslinking of short aliphatic chains by dicumyl peroxide and foaming by 1,1′-azobiscarbamide. The porosity of the foam determined by computer microtomography was 58.9%, and the bulk density was 0.42 g.cm−3. The sorption ability of the foam was tested using diesel oil, motor oil, and heavy crude oil. The absorption capacity of foam was characterized as the ratio between the mass of oil absorbed by the foam and the mass of a neat foam (Sw) and as the ratio between the volume of oil absorbed by the foam and the volume of a neat foam (Sv). The absorption capacities of the new foam reported in this study (referred to here as Qwax foam) are 6.6 ± 0.3 g/g, or 3.3 ± 0.2 cm3/cm3 for diesel oil, 3.9 ± 0.4 g/g or 1.9 ± 0.3 cm3/cm3 for motor oil, and 3.4 ± 0.2 g/g or 1.4 ± 0.4 cm3/cm3 for crude oil. To compare the sorption ability of Qwax foam with some standard foams, the absorption capacities of highly porous commercial polyurethane (PU) and melamine (MA) foams were investigated under the same conditions. These foams showed much higher sorption capacity considering the Sw parameter as a reference; however, there was a lower sorption capacity compared to parameter Sv. In the last paragraph, the suitability and the relevancy of parameters Sw and Sv for a comparison of the absorption capacity of foams were theoretically analyzed.

Combustion of crude oil during in-situ burning can introduce polycyclic aromatic compounds (PACs) into small-scale freshwater systems

In-situ burning (ISB) is the controlled combustion of an oil slick to remove large quantities of spilled oil from the aquatic environment. Prior to employing ISB as a remediation technique, an oil slick must often be corralled by physical or chemical means to achieve a sufficient thickness (typically >1 mm) for ignition. While ISB is an effective means to remove oil mass, less is known about the potential for ISB to mobilize polycyclic aromatic compounds (PACs) into the aquatic environment. The PACs are primary contaminants of concern in crude oil due to their environmental persistence and toxicity. We examined the potential for ISB to mobilize PACs into underlying waters in a series of small-scale burns conducted across a gradient of oil slick thicknesses (0–7 mm). Concentrations of PACs in underlying waters were evaluated and compared to reference conditions using an equivalent gradient of oil slick thicknesses that were not ignited. At thinner slick thicknesses (i.e. 0 – 4 mm) ISB enhanced the mobilization of total PACs, likely a result of heat transfer to underlying waters; this effect increased as slick thickness increased. Among thicker slicks (i.e. 4 – 7 mm), pyrogenic PACs became more prevalent and greater concentrations of 4-ring PACs were detected in underlying waters. The potential for PAC mobilization needs to be considered in scenarios where ISB may be the only viable oil spill remediation option (e.g. wetlands, marshes, or where oil is entrained) and in shallow systems susceptible to temperature changes.

PRODUKSI BIODIESEL DARI MINYAK KELAPA SAWIT DENGAN CO-SOLVENT FAME (FATTY ACID METHYL ESTERS) DAN APLIKASINYA PADA MOTOR BAKAR

The process of transesterification is slow due to the low solubility of triglycerides in methanol. The limitation of mass transfer can be overcome by adding a co-solvent. Co-solvent FAME is the right choice because it is the product of the reaction itself so that it does not require a separation process. The purpose of this study was to examine the use of FAME as a co-solvent in the transesterification of palm oil and its application to the combustion engine. The operating conditions were palm oil mass of 250 gr, NaOH catalyst 1.2% wt, stirring speed 100 rpm, reaction temperature 70oC, ratio molar of oil:methanol =1:6, reaction time (5,10,15,20,25,30 minutes), and co-solvent (0,5,10,15% wt). After the optimum conditions are obtained, the next step is to make biodiesel on a semi pilot plant scale. Oil, methanol, NaOH and co-solvent were put into a stirred reactor and heated at a reaction temperature of 70⁰C. After the reaction is complete then it is flowed into the separator for separation by adding hot water to form 2 layers. The top layer is biodiesel which was analyzed and performance test on the combustion engine. The optimum condition of the process is a reaction time of 10 minutes and the addition of 10% co-solvent, with a yield of 76.7783%. The results of the analysis of SNI 7182:2012 states that biodiesel meets almost all requirements. From the biodiesel performance test on the combustion engine, B10 got quite satisfactory results for the torque and opacity test parameters.

Determination of in situ hydrocarbon contents in shale oil plays. Part 2: Two-dimensional nuclear magnetic resonance (2D NMR) as a potential approach to characterize preserved cores

Determination of the in situ hydrocarbon content and occurrence characteristics of shale oil reservoirs is crucial for reserve prediction and efficient development. Although many scholars have studied the fluid saturation of conventional coring shale using solvent and thermal extraction methods, with time consuming and only volumes or mass of oil and water were given, which could not reveal the occurrence characteristics of oil and water in samples. This study proposes a two-dimensional (2D) nuclear magnetic resonance (NMR) T1–T2 mapping method to systematically assess the in situ water and oil content, distribution, and their evaporative loss laws of preserved shales. Sixty preserved shales with different maturities were selected from the first member of the Qingshankou Formation in the northern Songliao Basin, China. Each preserved sample was divided into two parts and analyzed using a high-frequency (22 MHz) NMR and Dean–Stark extraction respectively. Furthermore, a time-elapsed NMR T1–T2 mapping was performed on a preserved shale core sample after varying the exposure times in an open environment. Results show that T1–T2 mapping can be used to determine the porosity, water and oil contents, and saturations of preserved shales. Oil content measured using T1–T2 mapping was consistent with that obtained by Dean–Stark extraction, with a correlation coefficient (R2) as high as 90% when crude oils of varying maturities were used for NMR calibration.The T1/T2 of oil inpreserved shale showed a negative trend with maturity, and the T2 of oil was often higher than that of water, indicating oil is enriched in the relative macropores. After exposing the preserved shale to open air for 150–200 h, 1) the total loss ratio of oil and water was approximately 80%; 2)the fluid evaporation loss rate follows the orders: oil > water and fluids in larger pores > smaller pores; 3)the free oil content decreased by approximately 92%, whereas the absorbed oil content varied slightly. As a nondestructive, rapid, and minimal sample preparation method, 2D NMR can efficiently assess both fluids content and distribution of a core sample in only 5 min, thus displaying its great advantages and applications for preserved shales with fast fluid evaporation to determine the in situ fluid content.

Influence of different synthesis conditions on the chemo-enzymatic epoxidation of tall oil fatty acids

A side-stream of the cellulose pulping process – tall oil, was valorised for polyol precursor synthesis. The influence of various parameters on the tall oil self-epoxidation method was studied to increase the conversion towards oxirane rings while using a reduced amount of immobilised lipase catalyst – Novozym® 435 and hydrogen peroxide. The influence of synthesis time (0–7 h), process temperature (30–40 ℃), hydrogen peroxide (20–50 wt. %) and Novozym® 435 catalyst concentration (1.5–4.5 wt. % of tall oil mass) on the tall oil fatty acid self-epoxidation process was studied and optimised using response surface method. The shift in relative conversion to oxirane and ethylenic unsaturation was used to track the epoxidation process. The chemical structure change of the epoxidised tall oil was investigated using FTIR, 1H NMR and 13C NMR spectroscopies. The maximum relative conversion to oxirane of 81 % was attained at a relatively high Novozym® 435 catalyst loading of 4.5 wt. %. In comparison, the optimised relative conversion to oxirane of 73 % was achieved at a more feasible catalyst content of 3.2 wt. % after 7 h of synthesis, at hydrogen peroxide and tall oil molar ratios of 2.0/1.0, hydrogen peroxide concentration of 28 wt. % and synthesis temperature of 44 ℃.

Experimental investigation on oil transport, heat transfer and distribution performances of R32/oil mixture in microchannel evaporators

The aim of this study is to experimentally investigate the oil influences on transport, heat transfer and distribution performances of microchannel evaporator. Mixture of R32 and PVE VG68 oil was selected as the working fluid, and two single-pass microchannel heat exchangers were used as test samples. The experiments were conducted in mass flux range of 20–50 kg·m−2·s−1, nominal oil mass fraction (OMFno) range of 0–6% and inlet local quality range of 0.1–0.16 at the saturation temperature of 12 °C. The result indicated that the oil retention volume ratio (ORVR) increases with the increments in oil mass fraction, inlet quality and decrease in mass flux. The upper outlet header tended to have remarkable oil retention and the oil transport behavior in header was analyzed. In most cases, the heat transfer was suppressed by the addition of oil. Heat transfer enhancement was observed at low oil mass fraction and high inlet quality conditions. The heat transfer factor ranged from 0.95 to 1.03, which indicated that the oil effect on heat transfer was not significant. Although the presence of oil inhibited the saturated boiling heat transfer coefficient, it could promote the heat transfer at superheat region. Struggle of inhibition and enhancement effects resulted in slight oil effect on heat transfer performance. An infrared-image-based distribution rating parameter was utilized to quantify the distribution performance. The oil effect on flow distribution was slight and the flow distribution deteriorated as the mass flux increased. A theoretical model called liquid immersion model was adopted to describe the flow regime and distribution mechanism in inlet header.

Time domain NMR: An alternative for study of the asphaltenes precipitated in petroleum.

During the oil production and processing stages, the asphaltene precipitation is one of the great operation problems of oil industry. It can precipitate in the formation, tubing, or surface, causing operating problems, such as reduction in oil recovery by changing the reservoir permeability and wettability, clogging of the pipelines, and difficulty in separations process. The quantification of asphaltenes in petroleum by ASTM D6560 standard method is very laborious and use of a larger solvent volume than necessary. The present work proposes the use of time domain nuclear magnetic resonance (TD-NMR) as new methodology to quantify the asphaltene precipitated in crude oil. Three (light, medium, and heavy) crude oils with asphaltenes content of 0.97, 1.88, and 7.00 wt% were mixed with n-heptane in different R (ml of solvent/g of oil) values and analyzed by means of transverse relaxation time (T2 ). According NMR results, the R values enough for complete asphaltene precipitation for the oils A, B, and C were, respectively, equal to 16.50, 23.00, and 39.50 ml g-1 . These outcomes represent a reduction of 58.75%, 42.50%, and 1.25% in the solvent volume per mass of oil for the oil A, B, and C, respectively, compared to the ASTM D6560 method, which imposes 40 ml g-1 . Therefore, it has been shown that TD-NMR can be applied to estimate the amount of asphaltene precipitated in petroleum and have potential to be applied in routine analysis with advantages of saving time and costs.

Highly efficient separation of phenolic compounds from low-temperature coal tar by composite extractants with low viscosity

• Imidazolium IL-solvent composite extractants were applied for separation of phenolic compounds from oil. • The suitable composite extractants were identified by COSMO-RS calculation and viscosity determination. • [Emim][HSO 4 ]:EG (1:2) was selected due to its high phenol extraction efficiency, low oil entrainment, and low viscosity. • The separation mechanism was investigated by σ -profile, σ -potential, and FT-IR. Highly efficient separation of phenolic compounds from low-temperature coal tar (LTCT) is significant in the industry. In this work, composite extractants composed of imidazolium-based ionic liquids (ILs) and solvents were used to separate phenolic compounds from model oil and LTCT. First, the COSMO-RS model was used to screen composite extractants that combined the infinite dilution thermodynamic indexes and liquid–liquid equilibria (LLE) calculations. Meanwhile, the separation mechanism was analyzed by σ -profile and σ -potential. Then, the reliability of the COSMO-RS model was validated by LLE experiments and FT-IR. The viscosity of composite extractants with high separation performance was further determined. Among the composite extractants, 1-ethyl-3-methyl-imidazolium hydrogen sulfate ([emim][HSO 4 ])/ethylene glycol (EG) was selected as the most suitable extractant in the separation process. The m -cresol extraction efficiency and cumene entrainment were 98.1% and 8.3%, respectively, at a [emim][HSO 4 ]:EG molar ratio of 1:2, a temperature of 25 ℃, and a composite extractant: model oil mass ratio of 1:1. Moreover, the viscosity of [emim][HSO 4 ]:EG (1:2) was only 51.8 cP at 25 ℃ and decreased by 95.6% compared with pure [emim][HSO 4 ], which enhanced the mass transfer in the separation process. The [emim][HSO 4 ]:EG (1:2) could be regenerated and reused without significant reduction in separation performance. Finally, [emim][HSO 4 ]:EG (1:2) was applied to separate phenolic compounds from LTCT with a phenol extraction efficiency of more than 99.9% and a neutral oil entrainment of 8.3%, providing a promising prospect for the separation of phenolic compounds.

Analysis of a direct vapor generation system using cascade steam-organic Rankine cycle and two-tank oil storage

A direct vapor generation solar power system using cascade steam-organic Rankine cycle and two-stage oil tanks is proposed. It offers a significantly enlarged storage capacity due to the unique discharge operation mode. Synthetic oil Therminol® VP-1 is used as the heat carrier and storage medium. Compared with the direct steam generation system, the steam turbine inlet temperature is elevated from 270 °C to 311 °C. Thermodynamic analysis indicates that the optimal equivalent heat-to-power conversion efficiency (ηeq,opt) is 27.91% when benzene is used as the bottom fluid and the mass of oil is 1000 tonnes. ηeq,opt is raised by 7.72–11.60% for the selected four organic fluids as compared with the direct steam generation type. The temperature drop of oil during discharge can reach about 280 °C. Economic studies demonstrate that the proposed system is more cost-effective. Its equivalent payback period is less than 5 years for a 10 MW system with 2000 tonnes of oil. Further investigation shows that it is also more advantageous than a conventional thermal oil-based indirect solar power system due to the cost reduction in heat storage.

Biochemical composition of some <i>Melissa</i> L. and <i>Alcea</i> L. species introduced in Absheron

The article provides data on the study of the biochemical composition of the species Melissa officinalis, Alcea rugosa, A. kusariensis, A. hyrcana, A. rosea. Research were carried out in natural conditions and in Absheron, in cultural conditions on the experimental site of the Central Botanical Garden of the Azerbaijan National Academy of Sciences. The climate of Apsheron is mainly moderately hot and dry, subtropical and belongs to the semi-desert type. Gray-brown soils are widespread in the Central Botanical Garden. Of the studied species, two species, A. kusariensis and A. hyrcana, are rare species and listed in the “Red Book” of Azerbaijan. A. kusariensis is a rare endemic species of the Caucasus. A. hyrcana is a rare species in Azerbaijan. Determined primary moisture, hygroscopic moisture, the amount of dry matter, raw ash, raw fat and protein in the composition of the species. It was revealed that by the end of the growing season, the composition of the M. officinalis species decreases in crube ash, initial and hydroscopic moisture, while the amount of crude oil and protein increases. Compared to the underground part, the chemical composition of the aboveground part of the Alcea rugosa species is richer. Comparison of samples of this species growing in nature and in culture showed that the mass of raw ash and crude oil was higher in natural conditions, and the mass of protein was higher in cultured samples. Among the studied species, the prevalence of crude oil content was observed in A. hyrcana (4,35 %) and A. rosea (4,25 %) species, in A. kusariensis in terms of crude ash content (21,0 %), and in protein content in A. rugosa (22,5-28,19 %).

Development and testing of a SOSM approach to examine the natural attenuation of oil spillage on shorelines

Understanding the fate and behavior of spilled oil on the shoreline is crucial for helping decision-makers make trade-offs between natural attenuation and shoreline treatments. In this study, primary processes of oil attenuation and translocation on the shoreline, including penetration, washout, and biodegradation, have been considered to develop a numerical model, Shoreline Oil Spill Model (SOSM), for predicting the fate of spilled oil in various shoreline geological compartments. A holistic system design is employed to develop a user-friendly graphical interface system for SOSM. Global and local sensitivity analyses are used to examine the importance of the input factors on different outputs in SOSM. The results of the sensitivity analysis indicate that the input of oil spill mass correlates positively with the oil retention and surface and subsurface oil mass, while the oil concentration and penetration depth are sensitive to the grain size of the beach sediment. Subsequently, the SOSM is tested to hindcast the fate of stranded oil from the Exxon Valdez oil spill. Reasonable validation results have been obtained for the study site. It confirms the utility of the SOSM to examine and predict the level of shoreline oil contamination in the field following accidental spill events.