Residual Hydrocarbons Research Articles

Contamination presence and dynamics at a polluted site: Spatial analysis of integrated data and joint conceptual modeling approach

Contaminated sites are complex systems posing challenges for their characterization as both contaminant distribution and hydrogeological properties vary markedly at the metric scale, yet may extend over broad areas, with serious issues of spatial under-sampling in the space. Characterization with sufficient spatial resolution is thus, one of the main concerns and still open areas of research. To this end, the joint use of direct and indirect (i.e., geophysical) investigation methods is a very promising approach. This paper presents a case study aspiring to demonstrate the benefit of a multidisciplinary approach in the characterization of a hydrocarbon-contaminated site. Detailed multi-source data, collected via stratigraphic boreholes, laser-induced fluorescence (LIF) surveys, electrical resistivity tomography (ERT) prospecting, groundwater hydrochemical monitoring, and gas chromatography–mass spectrometry (GC–MS) analyses were compiled into an interactive big-data package for modeling activities. The final product is a comprehensive conceptual hydro-geophysical model overlapping multi-modality data and capturing hydrogeological and geophysical structures, as well as contamination distribution in space and dynamics in time. The convergence of knowledge in the joint model verifies the possibility of discriminating geophysical findings based on lithological features and contamination effects, unmasking the real characteristics of the pollutant, the contamination mechanisms, and the residual phase hydrocarbon sequestration linked to the hydrogeological dynamics and adopted remediation actions. The emerging conceptual site model (CSM), emphasizing the necessity of a large amount of multi-source data for its reliable, high-resolution reconstruction, appears as the necessary tool for the design of remedial actions, as well as for the monitoring of remediation performance.

Natural gas origin of Langgu Sag in Jizhong Depression, Bohai Bay Basin: Insight from hydrous pyrolysis experiments of gold tube

Two mudstone samples in low-maturity from the E2s3 source rock interval were used to hydrous pyrolysis experiments of gold tube with isothermal heating in order to better understand natural gas origins of Langgu Sag. The results displayed that the E2s source rocks in Langgu Sag attained the peak yield of nearly 350 mg/g TOC at about 0.9% of Ro for C6+ compounds due to thermal cracking occurrence of them if Ro higher than 0.9%, and C6-14 compounds would reach the maximum yield at about 1.3% of Ro owed to C14+ compounds preferentially cracking to them. Hydrocarbon gases were dominated by kerogen cracking gases at Ro lower than about 1.3% (referred to oil associated gases) and higher than about 1.8% (interpreted to residual kerogen cracking gases) but by secondary gases (belonged to early-generated liquid hydrocarbon cracking gases) if Ro at about 1.3%–1.8% for E2s source rocks. Furthermore, the yield of kerogen cracking gases would reach 90–100 ml/g TOC at 1.3% of Ro, far greater than 20 ml/g TOC as the lower limit standard of an effective gas source rock, even the kerogen cracking gas yield could reach 20 ml/g TOC if Ro at about 0.8%, therefore, as long as the E2s source rocks in Langgu Sag reach mature level, they can become effective gas source rocks.Considering their calculated Ro mainly distributing between 1.0% and 1.3% except Ordovician buried-hill reservoirs of the D2 oil-gas field, the proved natural gases in Langgu Sag mainly originated from kerogen cracking gases at Ro lower than 1.3%. And the gases from Ordovician buried-hill reservoirs of the D2 oil-gas field, with calculated Ro ranging about 1.3%–1.6%, essentially derived from residual liquid hydrocarbon cracking gases of the E2s4 source rocks, because the Ro of E2s3 source rock is mainly lower than 1.1% but it reaches about 1.8% for E2s4 source rock at present. The natural gases in shallow reservoirs experienced different degrees of bacterial degradation and formed methane-dominated gas reservoirs, consequently, the C1/C1-5 values displayed a range of 0.96–0.99 for bacterial degradation gas reservoirs and of 0.67–0.89 for natural gas reservoirs without bacterial reworking.

Transition towards Sustainable Carwash Wastewater Management: Trends and Enabling Technologies at Global Scale

Carwash wastewater (CWW) contains grease, oil, hydrocarbon residues, heavy metals, and surfactants, posing severe impacts to the environment and human health. Accordingly, various physical, chemical, and biological processes for CWW treatment have been demonstrated in recent research. In this study, a bibliometric approach was performed to comprehensively illustrate the recent progress, current direction, and future perspectives of CWW-related research. A keyword co-occurrence network was used to represent the results of the bibliometric analysis and to show the major pollutants in CWW effluents and the common systems for treating CWW via coagulation/flocculation, electrochemical, oxidation, membrane, adsorption, biological, and hybrid methods. An integrated anaerobic digestion/oxidation process has been reported to degrade CWW-associated pollutants and help develop an energy-efficient approach for waste management. The results demonstrated that the treatment of CWW has several benefits relevant to sustainable development, viz., good health and well-being, protection of life below water, bioenergy generation, and community awareness and acceptance towards wastewater reuse. Hence, these benefits could assist in meeting the environmental, economic, and social sustainable development goals (SDGs). These study outputs can encourage policymakers and stakeholders in implementing sensible regulations that control water usage and treatment in car sharing and personal vehicle services to either directly or indirectly adopt the agenda 2030 with its seventeen SDGs.

Nanoporous SiOx plasma polymer films as carrier for liquid‐infused surfaces

AbstractLiquid‐infused surfaces are based upon the infusion of a liquid phase into a porous solid material to induce slippery and repellent character. In this context, porous SiOx plasma polymer films represent a relevant candidate for a robust nanoporous carrier layer. Intermittent low‐pressure plasma etching of O2/hexamethyldisiloxane‐derived coatings is investigated to enhance the intrinsic porosity inherent to residual hydrocarbons in the silica matrix. Simulations of the resulting Si–O ring network structure using reactive molecular dynamics indicate formation of interconnected voids with Si–OH functionalized pore walls allowing water penetration with almost Fickian diffusive behavior. The corresponding porosity of up to 18%, well agreeing with simulations, Fourier‐transform infrared spectroscopy, and ellipsometry measurements, was found to be suitable for the liquid infusion of polyethylene glycol molecules into about 80 nm thick SiOx films providing ongoing lubricating properties, thus revealing their suitability as liquid‐infused surfaces.

Sexual dimorphism in cuticular hydrocarbons and their potential use in mating in a bushcricket with dynamic sex roles

Insect cuticular hydrocarbons provide desiccation resistance but may also be used in chemical signalling. Sexually dimorphic hydrocarbon blends, which may be transferred between individuals during copulation, are used especially in mate assessment. However, not all insect species produce sex-specific hydrocarbon blends, and their general utility in mate choice requires study of a broader range of species than is currently available. In the nuptial gift-giving bushcricket Kawanaphila nartee , sex roles vary depending on food availability: when food is scarce, females compete for access to males and their nuptial gifts, and when food is abundant, males compete for access to females. Given the scope for both male and female mate choice in the species, we hypothesized that their cuticular hydrocarbon profiles would differ. We characterized the cuticular hydrocarbon profiles of male and female K. nartee and found significant differences between them. Given the costly nutrient gifts provided by males at mating, we further hypothesized that males might use hydrocarbon residues left by rival males after mating to avoid investing in offspring sired by other males. Although females perfumed with male-derived hydrocarbon blends had lower mating success than control females, the difference was not statistically significant. We discuss the possible mechanisms that might favour the evolution of sexual dimorphism in cuticular hydrocarbon blends in this species. • Sexual dimorphism in cuticular hydrocarbons occurs in a sex role reversing insect. • Sexual dimorphism in hydrocarbons is not used by males in mate discrimination. • The dimorphism nevertheless provides a mechanism for sex discrimination. • The dimorphism may be used in mate choice by one or both sexes.

Sedimentary Environment and Enrichment of Organic Matter During the Deposition of Qiongzhusi Formation in the Upslope Areas—A Case Study of W207 Well in the Weiyuan Area, Sichuan Basin, China

For a more in-depth analysis on the marine chemical condition during the earliest Cambrian, mechanism of organic matter enrichment and exploration potential of shale gas resources, based on the petrology, organic geochemistry, and elemental characteristics of the W207 Well, this study discuss the Early Cambrian paleo-ocean environment and factors controlling of organic matter enrichment during the deposition of black strata Qiongzhusi Formation in the upslope areas, southwestern Sichuan Basin, Yangtze Block, China. The sedimentary cycles show that during the depositon of fine-grained Qiongzhusi Fm, interactive cycles of multiple deep-water and shallow-water shelf developed, and were controlled by the rise and fall in sea level. In particular, the slope turbidite (fan) and gravity flow sediments indicate that the shallow-water shelf facies were dominant in the upslope area (SW Sichuan Basin), where not in deep water for a long time, and the sedimentary thickness of the organic rich black shale was limited. Evidence from organic geochemistry indicates that the organic matter of the Qiongzhusi Fm from the W207 Well was mainly of type I kerogen, with a high degree of thermal evolution, little residual hydrocarbon, and low capacity for hydrocarbon generation. The redox parameters indicate that the marine environment on the upslope was medium restrictive, with some upwelling. The seawater had undergone a transformation according to anoxic–oxidic. Therefore, paleo-ocean productivity in the upslope area was generally low, and exhibited a prominent downward trend from bottom to top. Given its high risk of exploration, the authors suggest that the direction of shale gas resource evaluation should change to the intracratonic sag (downslope) area, which is characterized by deep-water shelf facies.

Status of oil pollution in water and sediment from Shatt Al-Arab Estuary and North-West Arabian Gulf

In the present study, an attempt was made to study the levels of petroleum hydrocarbon residues in Water and Sediment samples collected from ten stations at the region of Shatt Al-Arab Estuary and North-West of the Arabian Gulf. The water and sediment samples were analyzed by utilizing the spectrofluorometry technique. The results of the present research obviously indicated a degree of oil pollution, however, still lower in magnitude when compared with status in some other regional sites. The obtained levels of petroleum hydrocarbons in water was ranged from (3.09 µg/l) at station 7 to (30.87 µg/l) at station 9 while in sediment ranged from (19.43 µg/g) dry weight at station 4 to (49.09 µg/g) dry weight at station 9. In order to give a better evaluation of the petroleum hydrocarbon levels in the sediments, the Total Organic Carbon (TOC) percentage and grain size analyses were done by granulometry technique on selected slips of the bulk sediments obtained for this purpose. The mean percent TOC estimations ranged from 0.1 at Station 4 to 1.34 at Station 9. The mean values obtained in this study indicated that the petroleum hydrocarbon levels in the sediment samples are lower than the levels in sediment samples obtained with similar methodology and analyses in some of the Gulf States and countries in close vicinity of the region. The major pollution sources may involve tanker and boat discharges and activities, municipal sewage and rural runoff from land. Also, discharges and effluents from oil refineries, electricity generating station and industrial activities into the Basrah city are obvious.

Levels of Polycyclic Aromatic Hydrocarbons (PAHs) in muscles of commercial fishes from Iraqi waters

The concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in the muscles of eight kind of fishes from National Iraqi Waters, Five marine species viz., Euryglossa orientalis, Otolithes ruber, Lethvinus nebulosus, Epinephelus coioides and Johnieops sina which were collected from Iraqi marine waters, and three species viz, Cyprinus carpio, Carasobarbus luteus and Plantiliza abu which were collected from Shatt Al-Arab river fresh water. All fishes were collected during spring and autumn seasons within the year 2015. Recorded total polycyclic aromatic hydrocarbons in fish species from Iraqi national waters were varied between 0.054 and 155.44 ng/g, while for individual fishes: Anthracene recorded the highest values varied between 17.629 and 155.44 ng/g dry wet. Lower total PAHs value recorded was 197.54 ng/g dry wet. in O. ruber and higher total PAHs value recorded was 381.415 ng/g dry wet. in E. coioides, followed by P. abu which recorded higher total PAHs value of 275.938 ng/g dry wet. Large differences in the values of PAHs recorded during autumn 2015 were achieved which were lower than those recorded during spring. According to the ratios between low and high molecular weight PAHs, there are two sources for PAHs in the investigated fishes, the first was pyrogenic which was appeared in the fishes L. nebulosus and E. orientalis only for 0.355 and 0.274 ng/g respectively during spring 2015 and second anthrapogenic which appeared in all fishes except L. nebulosus and E. orientalis. Therefore during spring season the dominated source was the anthropogenic one. For the results of Autumn season, the ratios indicate predominant the values which were lower than 1 for mostly all studied fishes except that for E. orientalis which was equal to 1.040 indicating that most of the PAHs were from anthropogenic source. Although, concentration of petroleum hydrocarbons (PAHs) in fishes from national Iraqi waters along North West Arabian Gulf were recorded in most studied fishes, but they markedly higher than that in the background and previously reported studies in the same and nearby areas. From a public health point, petroleum hydrocarbon residue levels, especially the carcinogenic ones, in all fish samples analyzed in this study are considerably lower than the hazardous levels and doesn’t exert any health effect upon human being upon consumption.

Effect of H atoms and UV wideband radiation on cured low-k OSG films

Effects of hydrogen atoms and UV radiation (λ > 210 nm) on nanoporous organosilicate glass (OSG) low-k films are studied in the temperature range from 20 °C to 300 °C. The purpose of the study is to understand the mechanisms of low-k films modification that can happen during the cleaning from carbon containing residues formed from sacrificial porogen and accumulated during the air storage. It is shown that exposure of low-k films to hydrogen atoms at low temperature leads to slight modification of hydrocarbon bonds in hydrocarbon residues not bonded to Si. At high temperature (T ⩾ 300 °C), the relative concentration of –CH x bonds changes in a complex way and depends on the amount and structure of the carbon-containing compounds. The general trend is relatively rapid decrease of –CH2 bonds concentration, while the terminal –CH3 groups are more stable. Temperature also initiates the reaction of hydrogen atoms with low-k with partial modification of low-k matrix breaking Si–O bonds. The destruction of Si–O and Si–CH2 groups leads to the formation of oxygen-deficient centers, followed by the formation of Si–(CH3)2 groups due to their interaction with methyl groups. At 300 °C, the total number of Si–CH3 + Si–(CH3)2 groups starts to decrease indicating on partial removal of the methyl groups bonded to silicon. Besides with increasing temperature a slight modification of the structure of matrix under exposure to H atoms is also observed. UV radiation has almost no effect on these processes in the studied conditions. Thus, there exist the ‘optimal’ conditions for H atom impact on OSG low-k films which allows improving film performance by removing porogen residue without damage.

Hazard Analysis of Fixed‐Tube‐Sheet Shell‐and‐Tube Heat Exchangers

AbstractFixed‐tube‐sheet shell‐and‐tube heat exchangers (FTHEs) are widely used in process plants to enhance energy efficiency and to control temperature levels of unit operations. Even moderate temperature differences between shell and tube bundle of FTHEs can lead to failure mechanisms induced by thermal stress. To avoid equipment failure, design codes require an analysis of the transient response of an FTHE during special operating conditions. This work presents a modular‐hierarchical approach for the dynamic simulation of FTHEs, which is applied to special operating scenarios such as a loss of tube‐side flow, a shell‐side steaming‐out (cleaning procedure to remove hydrocarbon residues with steam) and a reactor trip (sudden stop of exothermic reaction).

Water Vapor Adsorption Capacity Loss of Molecular Sieves 4A, 5A, and 13X Resulting from Methanol and Heptane Exposure.

Zeolite-based molecular sieves are applied in industrial dehydration units for their high water uptake capacities and extremely low equilibrium pressure of water vapor. During their operational life, they tend to lose their water vapor adsorption capacity slowly. To optimize the usage of molecular sieves in dryer units, it is vital to understand the mechanism(s) leading to deactivation. In this work, the capacity loss was studied by exposing LTA- and FAU-type zeolites to methanol and heptane vapors under relatively harsh conditions using repetitive adsorption/regeneration cycles. A simple microflow unit was designed and used for the deactivation experiments. The water vapor adsorption capacity of the resulting samples was measured using a gravimetric analyzer. In addition, they were characterized by classic XRD, 13C NMR, and TGA techniques. The crystallinity of fresh and spent zeolite XRD patterns was not drastically affected even after exposure to the contaminants. It was found that methanol easily gave rise to a severe loss of water vapor adsorption capacity, much more so than heptane. Water vapor uptake in the methanol exposed samples is ∼50% lower than that for the fresh zeolites. This is attributed to nonvolatile, residual hydrocarbons.

Modelling of Bioremediation of Oil-Contaminated Soil Using Chicken Droppings as Biostimulant

The suitability of poultry droppings as a biostimulant for the remediation of crude oil-contaminated soil has been investigated. Four equal-sized containers, each containing 400g of soil were each contaminated 20 ml of crude oil after which they were thoroughly mixed. To first three containers, A,B and C were respectively added 20 g, 60 and 100 g of poultry droppings which were previously dried and pulverised. To the fourth container which served as control, was added no poultry droppings. The degradation of oil in the samples were monitored for 7 weeks by observing the residual hydrocarbon content (RHC) and pH of samples. The RHC of the samples over the seven-week period were then modelled using artificial neural network (ANN) in the MATLAB Neural Network Toolbox. The RHC values decreased for all samples, with the highest reduction of 100 mg/kg obtained in sample C and the least reduction of 1000 mg/kg in sample D. The PH values were observed to increase slightly from the acidic region of 5.5 to a range of 7.8 to 8.3. The best and most suitable training algorithm of RHC of the samples was TRAINSCG since it had the least mean square error (MSE) value of 0.00183 as well as the highest R-squared value of 0.99808.

Bioremediation of Crude Oil-Contaminated Soil using Compost as Bio-Stimulant

This study was conducted to investigate the usability of compost as a stimulant for the remediation of crude oil-contaminated soil. 2kg of porous sandy soil was measured into six different equal-sized cells and contaminated with 250 ml of sample crude oil. Masses of solid waste comprising of compost and sawdust were measured in varying amounts of 900g, 750g, 600g, 450g, 300g, and a control sample that had no compost and sawdust. The set-up was left to stand for eight weeks and the residual hydrocarbon content (RHC), pH, and total microbial count (TMC)of these samples were monitored and recorded. The percentage of hydrocarbon degradation that occurred in the treatment cells were; 33.11, 32.2, 31.2, 29.46 and 28.05 respectively, for the individual cells in the order above, while the control had a degradation rate of (0.44%) of the total hydrocarbon content after 8 weeks. pH values varied slightly within the ranges of 6.5-7.5. The TMC average values were 21, 188, 17,125, 15,000, 14,250, 13,125 and 0.1, with the highest count occurring in the sample having 900g of solid waste; followed by the other samples having lesser quantities of solid waste with the least value in the control. The resultant descent in TMC across each of the samples was due to the distribution of waste material in the samples, and the pH of the resulting mixtures remained at optimum, thereby favouring microbial growth across the samples.

Production of surface‐active sophorolipid biosurfactant and crude oil degradability by novel Rhodotorula mucilaginosa strain SKF2

AbstractBiosurfactants are produced by important types of microorganisms such as bacteria, yeast, and filamentous fungi and have been used in a variety of industries. Among the 15 crude oil‐degrading fungi, the two molds and one yeast were identified by 18S rDNA sequences as Mucor circinelloides strain SKMC, Fusarium fujikuroi strain DB2, and Rhodotorula mucilaginosa strain SKF2. These strains were isolated from crude oil–contaminated soil, diesel oil–contaminated soil, and activated sludge in the Oil Refinery Plant in Isfahan, Iran, respectively. The yeast strain was identified as a novel crude oil–degrading and biosurfactant‐producing fungi in the presence of (1% v/v) Iranian light crude oil in the minimal salt medium (MSM). The highest amount of the dry weight of produced biosurfactant was measured at 6.2 g L−1. Chemical nature of produced biosurfactant was determined as a surface‐active sophorolipid biosurfactant compound by thin‐layer chromatography, Fourier transform infra‐red spectroscopy, and gas chromatography–mass spectrometry (GC–MS) analysis. The residual hydrocarbons in the MSM were analyzed by GC–MS, and it was shown that octadecane and docosane were eliminated by this novel strain completely.

Sedimentary environment and organic matter enrichment of black mudstones from the upper Triassic Chang-7 member in the Ordos Basin, Northern China

The black mudstone of the Chang-7 Member is the most important source rock in the Ordos Basin. In order to understand the paleo-climate, weathering, redox conditions, salinity, water temperature, water depth, and primary productivity under which black mudstone of the Chang-7 Member was deposited, we have analyzed total organic carbon (TOC), rock pyrolysis parameters, major elements, and trace elements of 60 black mudstone samples from the Chang-7 Member of the Yanchang Formation in the Ordos Basin. Geochemical indicators such as TOC, volatile hydrocarbon and residual hydrocarbon (S1 + S2), hydrogen index (HI), chloroform asphalt “A”, maximum pyrolysis peak temperature (Tmax), Vitrinite reflectance (Ro), kerogen macerals, and other organic indicators, show that the kerogen type of the Chang-7 Member was type I–II1, the thermal evolution of organic matter was in the mature stage, and it has good hydrocarbon generation potential. The major and trace element characteristics, such as C-value, Sr/Cu, Rb/Sr and Mg/Ca ratios, chemical alteration index(CIA), Sr/Ba, B, Ga-B-Rb trace element triangle, B/Ga, 1000 × Rb/K2O, V/(V + Ni), pristane/phytane ratio (Pr/Ph), foraminiferal Mg/Ca, and Co values indicate that the sedimentary environment of the Chang-7 Member was semi-arid and semi-humid, with continental freshwater, a reductive sedimentary environment, and an average paleotemperature of 16 °C. Based on the analysis of Baxs and Ba/Al ratio, the Chang-7 Member has medium–high primary productivity, which together with the sedimentary environment, played an important role in the enrichment and preservation of organic matter.

Mineralogy, organic geochemistry, and microstructural characterization of lacustrine Shahejie Formation, Qikou Sag, Bohai Bay Basin: Contribution to understanding microcosmic storage mechanism of shale oil

Shale samples of lacustrine Shahejie Formation from the Well F39X1 drilled in Qikou sag were used to study microstructures, mineralogy, and organic geochemistry and their impacts on oil storage response. Samples are quartz and clay rich and contain a variable amount of calcite, dolomite, plagioclase, and pyrite minerals. The TOC content ranges between 0.33 and 2.59 wt %, Rock-Eval S 1 and S 2 values range from 0.05 to 1.07 mg/g and 0.12–9.57 mg/g, respectively. The maximum yield temperature (T max ) of pyrolysate ranges from 440 °C to 467 °C, and vitrinite reflectance calculated based on T max between 0.76 and 1.25%. High frequency 2D nuclear magnetic resonance (NMR) results show free oil contents are 1.176–1.909 μl/g, with an average of 1.542 μl/g. Mineral-related pores are dominant and volumetrically significant with a multimodal pore-throat size distribution, they could provide significant storage space and have good microstructural connectivity. Their roles in microscopic storage of oil molecules mainly depends on two mechanisms: (1) rigid mineral grains preserve large pore networks, within which residing a very large volume of free oil, and (2) clay particles existed within large interparticle pores alter pore throat size distribution, resulting in a slight increasing of adsorbed oil onto pore walls. The Well F39X1 is an important shale oil exploration well for Shahejie Formation. To reduce exploration risk and determine economic feasibility, knowledge of liquid hydrocarbon molecule microscopic storage mechanism is required so producible shale oil resources can be quantified. The investigation of oil-bearing shale mineralogy, organic geochemistry, and microstructures is an important step in better understanding of the pore network development and their related microscopic storage mechanism for oil in lacustrine shale. We suggested that siliceous Shahejie shales in Qikou sag with moderate TOC and suitable thermal maturity have well-developed pore networks and high residual hydrocarbons, which should be the important target for lacustrine shale oil exploration. Also, the well-developed mineral-related pore networks should be included in attempts to build realistic microscopic storage models of shales. • Four typical pore types in Shahejie Formation of Well F39X1 are identified. • Mineral-related pores are dominant and volumetrically significant in pore networks. • Oil molecule type, distribution, and content are identified by high-frequency 2D NMR. • Two microstructural models are proposed to reveal shale oil storage mechanism.

Обнаружение остатков и установление состава горючих компонентов при взрывах парогазовоздушных смесей

Introduction. Liquefied hydrocarbon gases (LHG) are widely used in various fields. The main components of LHG are: propane, isobutane and n-butane, which are not only combustible, but also explosive gases capable of detonation combustion. The detection of LHG in the air is a very urgent task in expert studies. To determine the component composition of various flammable liquids, for the purpose of their identification, chromatographs equipped with a capillary quartz column with a phase that allows detecting saturated hydrocarbons of the homologous series from pentane to pentatetracontane inclusive are used in the Forensic Expertise Institutions of Federal Fire Service of EMERCOM of Russia. However, it is not possible to analyze the component composition of lighter hydrocarbons according to the previously proposed and used in expert practice method for detecting and studying flammable liquids/high liquids under these conditions. To solve the problem of unification of the use of the instrumental base for the detection of residues of flammable liquids, liquid liquids and light hydrocarbons, new chromatography conditions were selected using the existing equipment set. Goals and objectives. The aim of the study is to select the analysis conditions for detecting the remains of liquefied hydrocarbon gases after explosions of steam-air mixtures on the basis of the instrumental gas chromatographic complex in service with the Forensic Expertise Institutions of Federal Fire Service of EMERCOM of Russia. Research methods. To detect and determine the composition of residues of combustible components during explosions of vapor-gas-air mixtures, a hardware-software instrumental complex based on a gas-liquid chromatograph equipped with a flame ionization detector, a ZB-50 capillary column, and an attachment from a two-stage thermal desorber was used. Results and its discussion. In the course of the study, the optimal conditions for conducting gas chromatographic analysis were defined and selected in order to detect liquefied hydrocarbon gases. Recommended pressures are given for various carrier gases. It is shown that, by varying the pressure and inlet temperature, light hydrocarbons propane, butane, isobutane is fairly well separated on a gas-liquid chromatograph with a flame ionization detector and on a ZB-50 capillary column 30 meters long. Conclusion. The research shows that the problem of combining a hardware-software instrumental complex based on a gas chromatograph with an attachment from a two-stage thermal desorber used for the analysis of two groups of substances (liquefied hydrocarbons and flammable liquids, gas liquids) is solved by varying the pressure and temperature of the input. Keywords: gas-liquid chromatography, thermal desorption, liquefied petroleum gases, light hydrocarbons, air-fuel mixtures, vapor-gas-air mixtures, explosion, fire examination.

Calculation and controlled factors of hydrocarbon expulsion efficiency using corrected pyrolysis parameters: A Songliao case study

In recent years, rock pyrolysis parameters combined with a mass balance method have been used to calculate the hydrocarbon expulsion efficiency. However, due to the experimental procedure of rock pyrolysis, the residual hydrocarbon amount (S1) is underestimated, and the hydrocarbon-generation potential of kerogen (S2) is overestimated, so that the hydrocarbon expulsion efficiency calculated from the pyrolysis parameters before correction is higher than the actual value. In this paper, the pyrolysis parameters were corrected by performing pyrolysis before and after the extraction of source rocks, and the hydrocarbon expulsion efficiency of the mudstone of the Qing 1 member of the Ha14 well in Songliao basin was calculated using the chemical kinetics method. The hydrocarbon expulsion efficiencies before and after the correction were considerably different, the hydrocarbon expulsion efficiency of the Ha14 well after correction was 17.5% lower than that before correction. The study show that the higher the abundance and maturity of source rock are, the higher the hydrocarbon expulsion efficiency is; the oil-type organic matter has a higher hydrocarbon-expulsion efficiency than the gas-type organic matter; the interbedded sand and mud type source-reservoir configuration relationship is beneficial to hydrocarbon expulsion; the underwater diversion channel phase has the highest hydrocarbon expulsion efficiency.

Analysis of Residual Hydrocarbons and Methanol in n-Butane on a Porous-Layer Capillary Column with Poly(1-Trimethylsilyl-1-Propyne)

Analysis of Residual Hydrocarbons and Methanol in n-Butane on a Porous-Layer Capillary Column with Poly(1-Trimethylsilyl-1-Propyne)

Technologies for capturing carbon dioxide and prospects of its utilization in depleted oil and gas fields

The problem of global warming and climate change requires global efforts to reduce the negative impact on the atmosphere. Capturing carbon dioxide is a key strategy in achieving pollution reduction targets. Reducing air pollution can be achieved by reducing the share of fossil fuels in the energy balance, introducing technologies for generating electricity from renewable sources and increasing the energy efficiency of production. An important step towards decarbonization is the introduction of carbon dioxide capture technologies in large industrial plants. These technologies involve capturing carbon dioxide during the combustion of coal or gas and transporting it to a disposal site with its subsequent storage without contact with the atmosphere. The most common technologies are post-combustion, pre-combustion, and combustion of oxygen-enriched fuels for carbon dioxide capture. Carbon dioxide emitted from flue gases can be used commercially, as a raw material for the food and chemical industries. A promi-sing direction for the utilization of large volumes of carbon dioxide is its injection into depleted oil and gas fields in order to increase the recovery factors of hydrocarbons. Using the main tools of hydrodynamic modeling, studies were carried out to increase hydrocarbon recovery of the Hadyach oil and gas condensate field in the conditions of the manifestation of a water drive. Based on the results of the studies carried out, it was found that in the case of introducing the technology of injecting carbon dioxide into the reservoir of the V-16 horizon, an increase in the final gas recovery factor is achieved by 2.95%, and condensate - by 1.24% of the residual hydrocarbon reserves. The results of the studies carried out indicate significant prospects for the use of carbon dioxide in the oil and gas sector of Ukraine within the framework of the entire process of decarbonization of energy-intensive production.