Heavy Hydrocarbon Fractions Research Articles

Indirect effects of oil products on the environment

The article is focused on chemical and radioactive contamination of the environment during hydrocarbon production. The objective of the research is to present relatively unknown facts of indirect long-term environmental effects of hydrocarbon production. Traces of radioactive contamination of soils, ground- and surface water were studied, and also in drinking water in the Republic of Bashkortostan. The authors’ own field and laboratory studies were used. They were performed as part of the preparation of geochemical base map (GHO-1000) of 1:1000000 scale in the Republic of Bashkortostan and in the Ukhto-Izhemsky oil and gas bearing region. The methods applied for laboratory research were inductively coupled plasma mass spectrometry (ICP-MS) for soil and bottom sediment samples and atomic emission spectrometry (ICP-AMS) for ground- and surface waters. It has been determined that in the areas affected by oil production the chemical pollution aspects include deterioration of the groundwater quality caused by associated water and oil products ingress into aquifers due to violation of the oil and gas well drilling techniques, and soil salination caused by frequent equipment breaks during oil production. Aspects of radiation contamination of the environment during oil production include the intake of radionuclides with associated water, and sometimes with heavy hydrocarbon fractions, as well as the consequences of underground nuclear explosions. It is concluded that the territories of hydrocarbon exploration, production and storage should be classified as areas of potential risk for radioactive contamination and chemical pollution (by inorganic compounds, including heavy metal salts). Uranium concentration in drinking water was determined by the INAA method (instrumental neutron activation analysis).

TECTONOSTRATIGRAPHIC EVOLUTION AND HYDROCARBON PROSPECTIVITY SOUTH OF GWADAR BAY, MAKRAN ACCRETIONARY WEDGE, OFFSHORE SW PAKISTAN

The Makran accretionary wedge developed as a result of subduction of the Arabian Plate beneath the southern margin of Eurasia since the Eocene. Interpretation of 2D seismic profiles calibrated to offshore well data in a study area to the south of Gwadar Bay (SW Pakistan) indicates a major period of accretion from the mid‐Miocene, as evidenced by the occurrence of thick growth strata associated with large‐scale imbricate thrusts. The thrust faults originate from a deep detachment within the mud‐rich Oligocene interval, and well‐developed piggy‐back basin successions occur in thrust hanging walls. In the study area, the thrust structures are sealed by a thick, progradational Pliocene to Recent interval in which the presence of submarine canyons, up to 2.5 km across, indicate that sedimentary transport was from the north.Fluid escape pipes and associated amplitude anomalies are observed in the seismic profiles studied and may be related to upward migration of thermogenic hydrocarbons from depth, as heavy hydrocarbon fractions <C3 have been reported from nearby wells. The hydrocarbons are believed to have been sourced from the Oligocene Hoshab Shale and to have then migrated up through a sedimentary succession in which permeability barriers are largely absent. Hanging wall anticlines mapped in the study area could provide structural traps, and turbidites in the Lower Miocene Panjgur Formation may represent a potential reservoir. Amplitude anomalies are also observed adjacent to shallow fluid escape pipes within the topsets of clinoforms in the Pleistocene Chatti and Omara Formations, and probably indicate the presence of biogenic hydrocarbons sourced from distal mudstones in bottomset strata.

Analisis dan Optimasi Pengaruh Suhu Gas Umpan Pada Kinerja Acid Gas Removal Unit

The Gas Gathering Station (GGS) in field X processes gas from 16 (sixteen) wells before being sent as selling gas to consumers. The sixteen wells have decreased in good pressure since 2011, thus affecting the performance of the Acid Gas Removal Unit (AGRU). The GGS consists of 4 (four) main units, namely the Manifold Production/ Test, the Separation Unit, the Acid Gas Removal Unit (AGRU), the Dehydration Unit (DHU). The AGRU facility in field X is designed to reduce the acid gas content of CO2 by 21 mol% with a feed gas capacity of 85 MMSCFD. A decrease in reservoir pressure caused an increase in the feed gas temperature and an increase in the water content of the well. Based on the reconstruction of the design conditions into the simulation model, the amine composition consisting of MDEA 0.3618 and MEA 0.088 wt fraction to obtain the percentage of CO2 in the 5% mol sales gas. The increase in feed gas temperature up to 146 F caused foaming due to condensation of heavy hydrocarbon fraction, so it was necessary to modify it by adding a chiller to cool the feed gas to become 60 F. Based on the simulation, the flow rate of gas entering AGRU could reach 83.7 MMSCFD. There was an increase in gas production of 38.1 MMSCFD and condensate of 1,376 BPD. Economically, the addition of a chiller modification project was feasible with the economical parameters of NPV US$ 132,000,000, IRR 348.19%, POT 0.31 year and PV ratio 19.06.

Integrating Thermal Analysis and Reaction Modeling for Rational Design of Pyrolytic Processes to Remediate Soils Contaminated with Heavy Crude Oil.

We developed a novel methodology that combines thermo-analytical measurements and mathematical methods to inform the reliable pyrolytic treatment of specific soil/contaminant systems. Our approach improves upon current "black-box" design methods that may overestimate the required treatment intensity and hinder cost efficacy. We used thermogravimetry and evolved gas analysis to characterize the complex network of soil mineral transformations, contaminant desorption, and pyrolytic reactions occurring when contaminated soils are heated in an anoxic atmosphere. The kinetics of these reactions were quantified using a distributed activation energy (DAE) approach with six pseudocomponents and used in a mathematical model for continuous-flow reactors to predict the removal of hydrocarbon contaminants without other fitting parameters. This model was tested with pilot-scale data from pyrolytic treatment of soils contaminated with crude oil and found to be a good predictor of the total petroleum hydrocarbon (TPH) removal for temperatures between 370 and 470 °C and residence times from 15 to 60 min. The light hydrocarbon fraction desorbed quickly, and over 99.7% removal was achieved at 420 °C and 15 min residence time. However, 95% removal of the heavy hydrocarbon fraction, which is a good proxy for polyaromatic hydrocarbons (PAHs), required 470 °C with 15 min residence time. This model can be employed to select operating conditions (e.g., reactor size, treatment time, and temperature) to reliably achieve remediation objectives for specific hydrocarbon/soil mixtures without inflating energy requirements, which would lower operating costs and decrease the process carbon footprint on a system-specific basis.

Bioaugmentation of Native Fungi, an Efficient Strategy for the Bioremediation of an Aged Industrially Polluted Soil With Heavy Hydrocarbons.

The concurrence of structurally complex petroleum-associated contaminants at relatively high concentrations, with diverse climatic conditions and textural soil characteristics, hinders conventional bioremediation processes. Recalcitrant compounds such as high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) and heavy alkanes commonly remain after standard soil bioremediation at concentrations above regulatory limits. The present study assessed the potential of native fungal bioaugmentation as a strategy to promote the bioremediation of an aged industrially polluted soil enriched with heavy hydrocarbon fractions. Microcosms assays were performed by means of biostimulation and bioaugmentation, by inoculating a defined consortium of six potentially hydrocarbonoclastic fungi belonging to the genera Penicillium, Ulocladium, Aspergillus, and Fusarium, which were isolated previously from the polluted soil. The biodegradation performance of fungal bioaugmentation was compared with soil biostimulation (water and nutrient addition) and with untreated soil as a control. Fungal bioaugmentation resulted in a higher biodegradation of total petroleum hydrocarbons (TPH) and of HMW-PAHs than with biostimulation. TPH (C14-C35) decreased by a 39.90 ± 1.99% in bioaugmented microcosms vs. a 24.17 ± 1.31% in biostimulated microcosms. As for the effect of fungal bioaugmentation on HMW-PAHs, the 5-ringed benzo(a)fluoranthene and benzo(a)pyrene were reduced by a 36% and 46%, respectively, while the 6-ringed benzoperylene decreased by a 28%, after 120 days of treatment. Biostimulated microcosm exhibited a significantly lower reduction of 5- and 6-ringed PAHs (8% and 5% respectively). Higher TPH and HMW-PAHs biodegradation levels in bioaugmented microcosms were also associated to a significant decrease in acute ecotoxicity (EC50) by Vibrio fischeri bioluminiscence inhibition assays. Molecular profiling and counting of viable hydrocarbon-degrading bacteria from soil microcosms revealed that fungal bioaugmentation promoted the growth of autochthonous active hydrocarbon-degrading bacteria. The implementation of such an approach to enhance hydrocarbon biodegradation should be considered as a novel bioremediation strategy for the treatment of the most recalcitrant and highly genotoxic hydrocarbons in aged industrially polluted soils.

Co-processing of Bituminous Coal with Heavy Hydrocarbon Fractions of Coal and Petroleum Origins into Pitch-Like Products

Co-processing of Bituminous Coal with Heavy Hydrocarbon Fractions of Coal and Petroleum Origins into Pitch-Like Products

Co-processing of Bituminous Coal with Heavy Hydrocarbon Fractions of Coal and Petroleum Origins into Pitch-Like Products

Co-processing of Bituminous Coal with Heavy Hydrocarbon Fractions of Coal and Petroleum Origins into Pitch-Like Products

Hydrogen enhanced biofuels for transport via fast pyrolysis of biomass: A conceptual assessment

The potential to increase biofuel output from a fast pyrolysis-based biorefinery through hydrogen enhancement is assessed for thermal fast pyrolysis (TFP) and catalytic pyrolysis (CAT) processes featuring bio-oil upgrade into gasoline, diesel and heavy hydrocarbon fractions. Results show that utilizing pyrolysis process off-gases to produce synthetic natural gas with an external hydrogen source could provide up to 48.2% (TFP) and 61.2% (CAT) reductions in biomass resource utilization. These savings are enabled by significantly improved carbon efficiency of the hydrogen enhanced designs, with efficiencies increasing from 40.5% to 66.3% for TFP and from 28.9% to 58.6% for CAT. Although the CAT process has a lower biofuel yield than the TFP process, it has a higher potential for hydrogen enhancement and achieves a higher biofuel output than TFP when fully enhanced with external hydrogen. The trade-off to the improved biofuel yield (higher carbon efficiency) is the substantial need for electricity to produce hydrogen via electrolysis, as for every megajoule (MJ) of biomass feedstock, 0.65–0.66 MJ of electricity is needed for the electrolyser.

Co-pyrolysis of oil sludge with polyolefins: Evaluation of different Y zeolites to obtain paraffinic products

One of the most hazardous contaminants, and the most significant waste by weight in the oil industry, is crude oil sludge. Oil sludge contains many toxic substances, posing risks to human health and the environment. Co-pyrolysis of petroleum sludge was carried out with polyolefins (HDPE, LDPE and PP) in the presence of different Y zeolites, to investigate the influence of these materials on obtaining a paraffin-rich pyrolytic liquid. Assays were performed in a fixed bed reactor at 450 °C for 15 min. The catalysts used have the same faujasite structure with similar textural properties and different acidity. The different polyolefins and catalysts had representative influences on product yield and composition. GCMS analysis allowed evaluating light (C9-C24) and heavy (≥C25) hydrocarbon fractions as well as detecting the presence of aromatic, paraffinic and cyclic compounds. The presence of polyolefins in oil sludge pyrolysis generated oily products with varied yields and compositions, directly related to the polymeric structure. The CBV720 catalyst allowed obtaining paraffinic products with a reduction of aromatic and cyclic compounds in petroleum sludge pyrolysis tests using linear structural chain polyolefins.

Lifting and yellow tip characteristics of small-scale partially premixed combustor burning pipeline natural gas and liquefied natural gas

In this article, a small-scale partially premixed combustor was designed with 1.5 kW heat input rate. Through altering premixing ratio of gas and air, the lifting and yellow tip characteristics were experimentally tested with the burner head material of cast-iron and copper–aluminum respectively. Combined with burner head temperature influences, the lifting and yellow tip characteristics of small-scale partially premixed combustor are discussed when natural gas is substituted. It is found that when lifting and yellow tip occur, the cast-iron burner shows a slow tendency of temperature change, but the temperature of copper–aluminum burner fluctuates sharply. Yellow tip is related to gas properties and burner structure, and is more likely to appear with the increase of the Wobbe index and heavy hydrocarbon fraction, while lifting is very likely to appear when temperature fluctuates. Yellow tip characteristic can be predicted by Wobbe index, but this method is unsuitable for lifting prediction.

Microbial treatment of waxy crude oil for mitigating wax precipitation and improving liquidity

The wax deposition of crude oil during transportation reduces the inner diameter, blocks the pipeline, and eventually increases the cost of petroleum production. This study reports a paraffin-degrading bacterial strain DG2 isolated from petroleum-contaminated soil. The effect of this strain on the removal of paraffin in crude oil was investigated. DG2, identified as Pseudomonas, produced biosurfactant that reduced the surface tension to 35.7 mN/m−1 and exhibited high emulsification activity. Results of gas chromatography–mass spectrometry analysis of the waxy crude oil treated by DG2 showed decreased heavy hydrocarbon fractions (C25 and C32). The degradation test revealed that DG2 reduced the wax appearance temperature by 4.16 °C and the viscosity by 23% of the waxy crude oil. These findings indicate that paraffin-degradation strain DG2 may be used for effective paraffin biodegradation.

Laboratory characterization of residual sludge from natural gas extraction by hydraulic fracturing in the Burgos Basin, Mexico

Pollutants and microbiota present in the residual sludge of hydraulic fracturing were determined and characterized physicochemically. Analyses included determination of pH, electric conductivity, organic matter percentage, as well as total carbonates, inorganic nitrogen and extractable phosphorous. In addition, presence of hydrocarbons by gas chromatography, potentially toxic elements (PTEs) by atomic absorption and presence of radioactive isotopes by gamma spectrometry were determined. Moreover, fungi and bacteria present in the residual sludge were classified taxonomically to the level of genus. Medium and heavy hydrocarbon fractions were found in concentrations above the maximum limits permitted (MLP) by Mexican environmental norms. Cu, Pb, Zn, Fe and Mg, however, were below the MLP. Likewise, gamma spectrometry analysis revealed naturally occurring Ac228, Ra226 and K40. The microbiological analysis found presence of the bacteria Bacillus spp., Micrococcus sp., Diplococcus sp. and Staphylococcus sp. and the fungi Trichoderma sp., Aspergillus sp. and Penicillium spp.

Isolation of Indigenous Hydrocarbon Transforming Bacteria from Oil Contaminated Soils in Libya: Selection for Use as Potential Inocula for Soil Bioremediation

The Libyan oil industry has left a significant legacy of contamination and methods are required to remediate oil-contaminated soils in the area. In this work hydrocarbon utilizing microorganisms were isolated and identified from contaminated soil samples obtained from an oil Refinery (Zawia, Libya). After initial screening of eleven isolates capable of growth on hexadecane, the five most promising hydrocarbon–utilizing bacteria were isolated and tested for biosurfactant production and emulsification activity. They were identified (using 16S rRNA sequence analysis) as Pseudomonas putida, Pseudomonas species, Betaproteobacterium, Actinomyces species, and Bacillus species. Among the five species tested, Pseudomonas putida showed superior performance in terms of growth on hydrocarbons (1.0×1010 CFU (ml)), E24 emulsifying activity (86%) and ability to transform hydrocarbons in pure culture. Interestingly, gas chromatographic analysis of crude oil treated with P. putida showed a decrease in heavy hydrocarbon fractions demonstrating a clear potential for this microbe to be used as a soil inoculant in bioremediation.

BIODEGRADACIÓN AEROBIA DE FRACCIONES DE HIDROCARBUROS PROVENIENTES DE LA ACTIVIDAD PETROLERA EN UN SUELO DE LA REGIÓN PATAGONIA NORTE, ARGENTINA

Recent techniques for assessing hydrocarbon contaminated sites are mainly based on risk analysis methodology. The effects of chemicals present in contaminated sites on the human health and the ecosystem are usually estimated as the addition of individual risks. In this sense, the hydrocarbon concentration is a relevant data. Bioremediation is a sustainable technology that accelerates the full or partial degradation of petroleum in contaminated soils and it shows a suitable cost-benefit ratio over other remediation methods. This work describes a laboratory scale study of the degradation rate for petroleum fractions by the incorporation of “biosolids” (sewage sludge) in an oil contaminated Patagonian soil. The determination of the total hydrocarbon concentration and the count of microorganisms in soil were performed both at the beginning and the end of the bioremediation process. The hydrocarbon degradation was analyzed at regular intervals during the study. The observed results showed that alkanes and lower molecular weight aromatic hydrocarbon concentrations were negligible after 14 days of treatment. The heavy hydrocarbon fraction, considered recalcitrant to biodegradation, was also significantly reduced during the biodegradation process. Since heavy hydrocarbons have low volatility and scarse migration by leaching, the observed decrease indicates that heavy hydrocarbon elimination could be mainly due to the native microorganism activity in the north Patagonian soils. Comparison with conventional treatment indicates that addition of “biosolids” enhances hydrocarbon remediation and that the biodiversity of microorganisms in soils is an important factor in achieving significant petroleum degradation.

1-3-1 重質炭化水素中の酸素のタイプ分析(1-3 構造・物性等,Session 1 石炭・重質油等)

1-3-1 重質炭化水素中の酸素のタイプ分析(1-3 構造・物性等,Session 1 石炭・重質油等)

Diesel-like hydrocarbon fuels by catalytic cracking of fat, oils, and grease (FOG) from grease traps

This work aims to investigate systematically the catalytic cracking of residual fat, oils, and grease (FOG) from grease traps to produce heavy diesel-like hydrocarbon fuels. The experiments were carried out in batch mode at 450 °C and 1.0 atm, with 5, 10, and 15% (wt.) Na2CO3 using a laboratory scale borosilicate-glass reactor of 143 ml, and with 10% (wt.) Na2CO3 in a pilot scale stirred tank slurry reactor of 143 l. The organic liquid products (OLP) were physical chemistry analyzed for acid and saponification values, density, kinematic viscosity, refractive index, flash point, and copper strip corrosion. FT-IR provided the qualitative chemical composition of OLP and heavy diesel-like fraction. The chemical compositions of OLP and heavy diesel-like hydrocarbon fuel determined by RMN and GC–MS. The laboratory experimental data showed an OLP yield ranging from 60.50 to 65.40% (wt.), a coke yield ranging between 7.50 and 9.80% (wt.), and a gas yield ranging from 16.30 to 22.06% (wt.), while pilot scale data showed an OLP yield of 66.57% (wt.), a coke yield of 9.73% (wt.), and a gas yield of 18.24% (wt.). In addition, the yield of OLP obtained in laboratory scale shows a slight increase with Na2CO3 content, while the density, kinematic viscosity, acid value, and saponification value decreases in an exponential fashion with Na2CO3 content. The OLP acid values varied from 19.08 to 71.50 mg KOH/g, the density between 0.827 and 0.867 g/cm3, and the kinematic viscosity from 3.90 to 6.35 mm2 s−1 for laboratory data, while in pilot scale, the OLP acid value was 14.97 mg KOH/g, density of 0.820 g/cm3, and the kinematic viscosity of 3.485 mm2 s−1. The yield of heavy diesel-like hydrocarbon fraction average 19.35% (wt.) with an acid value of 7.27 mg KOH/g, density of 0.812 g/cm3, and kinematic viscosity of 3.51 mm2 s−1. FT-IR, RMN, and GC–MS analysis of OLP and heavy diesel-like hydrocarbon fraction confirms the presence of functional groups characteristic of hydrocarbons (alkenes, alkanes, ring-containing alkenes, and ring-containing alkanes, cycloalkenes, cycloalkanes, and aromatics) and oxygenates (carboxylic acids, ketones, fatty alcohols, and dienes). The GC–MS analysis of OLP and heavy diesel-like hydrocarbon fraction obtained in pilot scale with 10% (wt.) Na2CO3 identified in OLP 76.97% hydrocarbons (39.44% alkenes, 31.91% alkanes, 4.12% ring-containing alkenes, and 1.50% ring-containing alkenes) and 23.03% oxygenates (12.14% carboxylic acids, 6.98% ketones, 1.90% fatty alcohols, and 2.01% dienes). The heavy diesel-like hydrocarbon fuel is composed by 69.27% (area) hydrocarbons (32.04% alkenes, 25.62% alkanes, 3.93% ring-containing alkenes, 0.98% ring-containing alkanes, 1.35% cycloalkanes, 4.88% cycloalkanes, and 0.47% aromatics) and 31.75% (area) oxygenates (4.80% carboxylic acids, 4.85% ketones, and 21.08% fatty alcohols). The physical-chemistry properties and chemical composition of heavy diesel-like hydrocarbon fuel obtained by catalytic cracking of residual fat, oils, and grease (FOG) from grease traps with 10% (wt.) Na2CO3 shows the process is technically feasible.

Identification of the medicinal plant species with the potential for remediation of hydrocarbons contaminated soils

In this work we describe several plants identified in a field site within 91,659 m radius of influence of a former refinery contaminated with benzene, toluene, ethylbenzene and xylenes (BTEX), as well as light hydrocarbon fraction (C5–C10, LHF), middle hydrocarbon fraction (C10–C28, MHF) and heavy hydrocarbon fraction (C28–C40, HHF). Nine medicinal plant species were identified at the site and the number of individuals of each was determined as Sida rhombifolia (166), grasses (133), Baccharis salicifolia-Senecia salignus (115), Fraxinus sp (67), Wigandia orens (39), Buddleia cordata (27), Nicotiana glauca (26) and Phytolacca icosandra (13). An important feature of the identified plants was their medicinal properties, in addition to their survival at field conditions with high hydrocarbon concentrations (LHF, MHF, HHF and BTEX), that make them suitable species for soil phytoremediation.

Effects of mass transfer resistance and coking on yield during fluid catalytic cracking of heavy hydrocarbon fractions

A transient model for an industrial fluid catalytic cracking (FCC) riser is here presented. The FCC riser models of previous researchers were mostly based on the assumption of negligible mass transfer resistance. This assumption reduced the accuracy of the models. In this work, the effects of mass transfer resistance and coking on the yield of FCC reactions were modeled and simulated. A five-lump reaction scheme was used to model the cracking reactions. Catalyst deactivation was modeled based on the exponential decay function. The mass transfer coefficient and the catalyst effectiveness factor were estimated from empirical correlations obtained from literature. The model parameters that were used in this investigation were sourced from the field as well as from literature. The reaction model was solved using COMSOL Multiphysics 4.0. The major difficulty encountered in this investigation was the unavailability of experimental data from which the mass transfer resistance, catalyst effectiveness factor, kinetic constants of the cracking reactions and effective diffusivities of species could be determined. This challenge was overcome by using empirical correlations from literature to estimate the terms. Model data which could not be obtained from the plant were sourced from literature and duly referenced. The proposed model vividly showed that mass transfer resistance significantly affects FCC reactions. Previous models over-predicted the residence time of the riser while under-predicting the over-cracking point of gasoline (the key product). A residence time of 2s and a gasoline yield of 45% were predicted by this model. Key words: Fluid catalytic cracking (FCC), Transient model, mass transfer resistance, catalyst deactivation, Riser models.

Recovery and Characterization of Oil from Waste Crude Oil Tank Bottom Sludge from Azzawiya Oil Refinery in Libya

In this work we present the results of quantitative and qualitative analyses of oil obtained from crude oil tank bottom sludge (COTBS) generated from Azzawiya oil refinery in Libya. The aim of the study was to recover and evaluate oil from waste oily sludge and to compare it with parent oil (Hamada crude oil) in order to assess the commercial potential of recycling the oil. The benefits would be two-fold, firstly to improve oil utilisation efficiency and secondly in reducing the environmental contamination associated with the petrogenic hydrocarbon industry. Oily COTBS and extracted oil were characterised and key properties were measured including water and oil content, light and heavy hydrocarbon content, solid content and organic matter content for COTBS and water content, density, specific gravity, API (American Petroleum Institute) gravity, viscosity, salt and ash content for the extracted oil. Solvent (hexane) extraction confirmed that the oily sludge contained 42.08% (± 1.1%) oil composed of light hydrocarbons (30.7 ± 0.07%) and heavy hydrocarbon (69.3 ± 0.4%) fractions. The water and solid contents were 2.9% (± 0.2%) and 55.02% (± 0.6%) respectively. The properties of the recovered oil were assessed; gas chromatograph spectrophotometer (GC-MS) results indicated that the oil contained 139 different hydrocarbon fractions with a total petroleum hydrocarbon (TPH) concentration of 29,367 mgkg-1 and a polycyclic aromatic hydrocarbons (PAH) concentration of 11,752 mgkg-1. Several parameters of the oil were measured and compared to the parent oil (Hamada crude oil) including density, specific gravity, viscosity, salt and ash content. The API of the extracted oil (33.03) was lower than the parent oil (38.8) due to a reduced light hydrocarbon (LHC) content. TGAFTIR hyphenation shows both mass loss of hydrocarbons— low, medium and high molecular mass over a range of temperatures between 60°C and 450°C. crude oil extract exhibited a non-Newtonian behaviour (shear thinning) for the shear rate sweep between 10 and 500/s. dynamic shear rheology data showed that the extracted oil exhibit more like a solid than liquid. Overall the findings of the study confirmed that COTBD has a significant amount of oil similar in properties to Hamada crude oil. This large amount can be reclaimed and recycles. Depending on this essay, a commercial process could be performed which in parallel will reduce the environmental contamination with hydrocarbons.

Protocols for the analysis of transformer oil and its degradation in soil by hydrogen peroxide

Conventional gas chromatography (GC) analysis of hydrocarbons displaying one broad peak provides limited information. Two GC analytical protocols using two-peak and three-peak approaches were developed to investigate transformer oil components and their degradation in soil by hydrogen peroxide. The two-peak method revealed transformer oil to be composed of 27 wt.% F2 fraction and 73 wt.% F3 fraction hydrocarbons. The three-peak method segregated the transformer oil into 40 wt.% light, 40 wt.% medium, and 20 wt.% heavy hydrocarbon fractions. In contrast to reports of success with several classes of lighter hydrocarbons, only limited degradations of transformer oil in soils by 15% and 30% hydrogen peroxide treatment was indicated by conventional one-peak analysis; two-peak analysis showed varying F2 and F3 fraction degradations with F2 fraction degradation being higher; three-peak analysis offered a richer understanding of the relative degradations of light, medium, and heavy fractions. The effect of a low pH environment on the degradation of transformer oil by hydrogen peroxide was evaluated using the three-peak method. It emerged that the degradation of the medium and heavier fractions of transformer oil was higher at pH 2·0.