Asphaltite Samples Research Articles

Asphaltite Pyrolysis in Fluidized Bed Reactor

In this study, the pyrolysis properties of asphaltite samples taken from Şırnak and Hakkari regions in a fluidized bed reactor under catalyst and non-catalyst conditions were determined by rapid and batch pyrolysis. Basic analysis, FTIR and XRF analyses were performed for the raw material. GC-MS analysis methods were used for liquid pyrolysis products and FTIR were used for solids. In order to acquire the condition of the highest liquid product yield in pyrolysis, several effective variables such as particle diameter, vacuum, nitrogen flow rate, temperature, raw material feed rate, catalyst type, raw material type and duration were experimented and the results were evaluated. In general, the vacuum effect has led to an increase in liquid product yield and a decrease in gas product yield. Liquid product yield increased at 700°C pyrolysis temperature in continuous feed system and 550 - 650°C in batch system. In the pyrolysis studies carried out, a maximum liquid product yield of 16.5% was achieved in the continuous fed reactor at 700°C temperature, 400 mmHg vacuum, 2 g/min feed rate and 500 µm particle size.

Radiochemical Procedure for Measurement Specific Activities of Uranium Isotopes in Asphaltite Bioleaching Liquor by Alpha-Particle Spectrometry

An analytical procedure for the alpha-source preparation is investigated in the study to determine uranium radioisotopes specific activities in the bioleaching liquor leach from asphaltite samples taken from the Silopi region in Türkiye. The purpose is to develop a new radiochemical method that can provide the alpha-particle spectrometry requirements. The proposed analytical procedure includes sample preparation, radiochemical purification of uranium from bioleaching liquor, alpha-source preparation on a substrate and alpha-particle spectrometric analysis of isolated uranium. The method is valid for availability using the z-test, relative bias, and relative uncertainty outlier tests. The results show that the proposed analytical procedure is successfully implemented for measuring the activity concentration of uranium with high accuracy and precision in the bioleaching liquor.

Investigation of the cleanability of asphaltite by flotation

Southeastern Anatolia Region of Turkey/Sirnak asphaltites centers are located in and around large reserves in coal mines. Due to the high ash and sulfur content of asphaltite coal, it is important to use it by cleaning with enrichment methods, in terms of solving environmental problems and increasing energy quality. In this study; the main characteristics (chemical analysis, ICP-OES, XRD, SEM analysis) of the asphaltite samples taken from the Avgamasya quarry operating in the center of Sirnak province were determined after the crushing and grinding processes. Later, the asphaltite coal sample was subjected to the flotation enrichment method, which is widely used in fine particle size coal enrichment methods. In the flotation method, the effects of kerosene, fuel oil, and aerophine3418A reagents in different amounts were investigated. Accordingly, the best ash results in the A1(50 g/t kerosene + 0.1 g/t MIBC) experiment; were obtained by adding 50 g/t kerosene reagent and the ash content was determined as 30.80% with an ash content reduction from 46.08% to 33.16%. Best result for reducing the sulfur ratio; in the B2(100 g/t fuel oil + 0.1 g/t MIBC) experiment, it was determined by the addition of 100 g/t fuel oil reagent. Here, the total sulfur content was reduced from 6.46% to 5.71% with a sulfur content reduction of 11.61%.

Comparison of Three Sequential Extraction Methods for the Determination of Iron, Manganese, and Thallium in Asphaltite Samples

Comparison of Three Sequential Extraction Methods for the Determination of Iron, Manganese, and Thallium in Asphaltite Samples

Cleaning of fine asphaltite by oil agglomeration process

ABSTRACT In Turkey, asphaltite deposits are located in the Southeastern Anatolia region in the form of fleets around the Sirnak province and its environs. According to the research, although the lower thermal values of Sirnak asphaltites are between about 11–24 MJ/Kg, the ash contents are between 35% and 55% and the total sulfur rates are between 3% and 8%. Asphaltite with high-ash content ratios can be cleaned by applying coal preparation and enrichment methods and made into high-quality energy raw materials with higher calorific value. Most fine-grained coals are disposed of without use or any economic consideration and cause environmental pollution. The oil agglomeration method, which is one of the methods of ore enrichment used to clean very fine coals, can be applied for coal samples. In this study, chemical and sieve analyzes of asphaltite samples taken from the Seguruk and Avgamasya mine sites operating within the borders of the Sirnak province were carried out and oil agglomeration enrichment method was applied with different types of oil and ash content were reduced. Under the conditions determined, the ash content of the Seguruk asphaltite sample called sample-A was reduced from 45.14% to 19.91% and the ash content of the Avgamasya asphaltite sample called Sample-B was reduced from 43.65% to 18.72%.

Geological and physical-chemistry characterization of asphaltite from Colombian Middle Magdalena region

The massive consumption of fossil hydrocarbons and the absence of new conventional oil reserves, research on unconventional resources is prevalent. The Asphaltite is a substance with high energy value thanks to its composition of high molecular weight hydrocarbons, becomes an energy alternative in the future. In Middle Magdalena region of Colombia, Luna formation emerges with its members Salada, Pujamana, and Galembo of Upper Cretaceous age, which contains a deposit of this type of substances, which can become an economic and energy engine for the region. A representative sample of this asphaltite was taken in the Galembo Member (Top of Luna formation) and a geological description was made about its formation and occurrence in the area. The solubility of asphaltite was evaluated in two characteristic solvents for hydrocarbons, toluene and heptane, the first of aromatic character, with which it was possible to solubilize probably corresponding to the light fractions, while solubilization with heptane generated a precipitate Asphaltene, a nature that was corroborated by tests of visible infrared and ultraviolet spectroscopy, additionally an elementary analysis was performed to determine the concentrations of carbon, hydrogen, sulphur and oxygen. Finally, by means of thermogravimetry and differential scanning calorimetry an analysis was carried out to evaluate its energy potential, according to the results obtained, asphaltite samples are a promising energy resource.

AN INTRODUCTION TO THE PRECAMBRIAN PETROLEUM SYSTEM IN THE SANKURU‐MBUJI‐MAYI‐LOMAMI‐LOVOY BASIN, SOUTH‐CENTRAL DEMOCRATIC REPUBLIC OF CONGO

This study presents a preliminary assessment of the petroleum potential of the Meso‐Neoproterozoic Mbuji‐Mayi Supergroup in the Sankuru‐Mbuji‐Mayi‐Lomami‐Lovoy Basin in the southern‐central Democratic Republic of Congo. This basin is one of the least explored in Central Africa and is a valuable resource for the evaluation of the petroleum system in the greater Congo Basin area. Highly altered carbonates (potential reservoir rocks) and black shales (potential source rocks) are present in the Mbuji‐Mayi Supergroup, which can be divided into the BI and overlying BII groups (Stenian and Tonian, respectively). For this study, samples of the BIe to BIIe subgroups from five boreholes and two outcrops were evaluated with petrographic, petrophysical and geochemical analyses.Carbonates in the BIe to BIIe subgroups with reservoir potential include oolitic packstones and grainstones, stromatolitic packstones and boundstones, various dolostones, and brecciated and zoned limestones. Thin section studies showed that porosity in samples of these carbonates is mainly vuggy and mouldic with well‐developed fractures, and secondary porosity is up to 12%. Black shales in the BIIc subgroup have TOC contents of 0.5–1%, and the organic matter is interpreted to have been derived from precursor Type I / II kerogen. The thermal maturity of asphaltite in carbonate samples is indicated by Raman spectroscopy‐derived palaeo‐temperatures which range from ∼150 to ∼260°C, which is typical of low‐grade metamorphism. Raman reflectance (RmcRo%) values on asphaltite samples were between 1.0 and 2.7%, indicating mature organic matter corresponding to the oil and wet gas windows. Source rock maturation and primary oil migration are interpreted to have occurred during Lufilian deformation (650–530 Ma). The solid asphaltite present in fractures in the dolostones of the BIIc subgroup may represent biodegraded light oil from an as‐yet unknown source which probably migrated during the Cambrian‐Ordovician (∼540–480 Ma). This migration event may have been related to the effects of the peak phase of Lufilian deformation in the Katanga Basin to the SE.This study is intended to provide a starting‐point for more detailed evaluations of potential hydrocarbon systems in the Sankuru‐Mbuji‐Mayi‐Lomami‐Lovoy Basin and the adjacent greater Congo Basin area.

Organic geochemistry of the asphaltite occurrences in the Gümüşhacıköy (Amasya) Area, Northern Turkey

The asphaltites are exposed in three different locations (Gökçukur Plato, Kağnıcı, and Saraycık villages) in NW Gümüşhacıköy (Amasya), Northern Turkey. In this study, organic geochemical characteristics of the asphaltite occurrences were investigated and correlated with each other.The Saraycık asphaltite occurrences are found in the Eosen unit that consists of mainly sandstone, siltstone, claystone, and limestone. The asphaltites are located in the joint systems of this unit and porosity of sandstone and siltstone. Kağnıcı asphaltite occurrences are found in agglomerates and tuffs of the Eocene age. The asphaltite occurrences in agglomerates and tuffs fill primary porosity and have an irregular and patchy distribution. Gökçukur asphaltites are found in the ophiolitic mélange of the Upper Cretaceous age. The asphaltite occurrences are located in the joint systems of this formation. TOC values of Saraycık, Kağnıcı and Gökçukur asphaltite samples are 1.16%, 9.35% and 21.22% and respective HI values are 757, 92 and 306mg HC/g TOC.The δ13C values of saturated and aromatic fractions from the asphaltites are similar, but the aromatic fraction of Gökçukur asphaltite sample is enrichment in δ13C compared with the others. n-Alkane, isoprenoid, and aromatic fractions were almost completely depleted in the gas chromatograms of Saraycık and Kağnıcı asphaltite samples. n-Alkanes and isoprenoids are recorded in a low amount in gas chromatograms of Gökçukur asphaltites.The asphaltite samples from Kağnıcı, Saraycık, and Gökçukur locations show similar diasterane and sterane distributions in the m/z 217 mass chromatograms. These asphaltite samples have lower diasterane and higher sterane abundances. In all the asphaltite samples, C27, C28, and C29 sterane distributions are similar. Regarding the sterane abundances, there is a general ranking of C29>C28>C27. Iso-, normal-, and dia-sterane abundances of Kağnıcı and Gökçukur asphaltites are ranked as normal->iso->dia-sterane. Iso-sterane contents of the Saraycık asphaltites are significantly greater, and normal sterane abundance is lower than the others. Gökçukur and Kağnıcı asphaltite samples have similar tricyclic terpane, hopane, and homohopane distributions in m/z 191 mass chromatograms. In m/z 191 mass chromatogram of Saraycık asphaltite sample, tricyclic terpanes were recorded in high abundances, whereas hopanes and homohopanes were recorded in lower abundances. Kağnıcı and Gökçukrur asphaltites have lower tricyclic terpane and higher hopane distributions. ββ/(ββ+αα) sterane, 22S/(22S+22R) homohopane, and the low moretane/hopane ratios show that all the asphaltites are mature.

Occurrences and origin of oils and asphaltites from South East Anatolia (Turkey): Implications from organic geochemistry

SE Anatolia hosts the most important oilfields and asphaltite deposits in Turkey. Here, we report on the organic geochemical characteristics of crude oil samples from four wells (Yolaçan-1, Çamurlu-28, B. Kozluca-22 and D. Sınırtepe-1) located to the west of Mardin city, one oil from a well (Özlüce-1) to the north of Batman city, and asphaltite samples from the Avgamasya, Herbol and Seridahle localities.Reservoir rocks for the oils from the Özlüce-1, Çamurlu-28, B. Kozluca-22 and D. Sınırtepe-1 wells are Lower Cretaceous limestones and dolomites of the Alt Sinan Formation. At well Yolaçan-1, the oil is reservoired in the carbonates of the Lower Cretaceous Mardin Group. At Avgamasya and Seridahle, asphaltites occur in joint systems in the Upper Cretaceous–Paleocene Germav Formation; the Herbol asphaltites are located in the Eocene Gercüş Formation.Except for the Seridahle asphaltite sample, δ13C values of all other oils and asphaltites are very similar. Gas chromatograms indicate that while the Özlüce-1 oil sample predominantly contains n-alkanes with medium carbon number (C13–C20) the other oil samples predominantly contain n-alkanes with low carbon number (C4–C11).Except for the Özlüce-1 oil sample, all the other oil and asphaltite samples show similar C27, C28 and C29 sterane distributions, with C29 being the dominant sterane. Based on the C28/C29 sterane ratio, the Özlüce-1 oil derives from a younger source when compared to the other oil and asphaltites. The diasterane/sterane, Ts/(Ts+Tm), C29/C30 hopane ratios and C24 tetracylic terpane abundance indicate that all the oil and asphaltite samples are of similar character except for the Özlüce-1 oil sample, which is characterized by higher diasterane/sterane and Ts/(Ts+Tm) ratios, a lower C29/C30 hopane value and lower C24 tetracylic terpane content. The C31–R/C30 ratio indicates a marine source for all oil and asphaltite samples.Normal alkane, isoprenoid, biomarker and isotope data indicate that the all the crude oils (with the exception of that from Özlüce-1) and all the asphaltites are geochemically similar and were generated from marine carbonate source rocks. The Özlüce-1 appears to have been derived from a clay-rich source rock.Based on geology of the basin and their geochemical characteristics, it is suggested that all oils (except Özlüce-1) and asphaltites were generated from Triassic–Jurassic carbonates of the Cudi Group. The source rock of Özlüce-1 oil may be Cretaceous marl or limestone of the Karababa Formation or clay-rich limestone of the Beloka Formation.

Effect of mineral matter on the isothermal pyrolysis product of Şırnak asphaltite (Turkey)

Isothermal pyrolysis of raw and demineralized Şırnak asphaltite (SASP) was investigated to determine product yield and distribution of volatile products at different temperatures. First, asphaltite sample treated with HCl, HNO3 and HF to remove carbonates, pyrite and silicates from organic structure. Then, raw and these treated asphaltite samples were pyrolyzed in isothermal pyrolysis reactor at 450, 500, 550, 600 and 650°C. Pyrolysis products were analyzed by capillary gas chromatography. Volatile hydrocarbon recovery (VHR) and total hydrocarbon recovery (THR) were calculated. VHR and THR were increased with increasing temperature. In contrast, solid residue decreased. Removal of carbonates and pyrite decreased the volatile product yield. However, for HF treated samples gas product evolution increased. Carbon balance established around the reactor, carbon in solid residue was determined and asphaltene and pre-asphaltene fractions were calculated. In addition, n-paraffins and 1-olefins were grouped according to the carbon number.

Organic geochemical comparison of asphaltites of Şırnak area with the oils of the Raman and Dinçer fields in Southeastern Turkey

Fifty-five samples of asphaltites from 12 different veins in Şırnak area and two oil samples from Raman and Dinçer Oil fields in South East (SE) Turkey have been analyzed by organic geochemical methods (total organic carbon, rock–eval pyrolysis, gas chromatography of saturated fractions, gas chromatography-mass spectrometry and stable carbon isotope). The total organic carbon (TOC) contents in asphaltites ranged from 12% to 65%. The Tmax values range between 428°C and 465°C. The hydrogen index (HI) values vary between 270 and 531mg HC/g TOC. The levels of biodegradation of the asphaltites were studied by GC analyses of the saturated fractions and none to moderate biodegradation has been found. Maturity of the asphaltite samples were assessed biomarker ratios provided by GC-MS analysis. Stable carbon isotope (13C) analyses of Raman–Dinçer oils produced values about −27‰ and the asphaltene fractions of the asphaltite samples revealed similar values about 26.8‰. It is presumed that the asphaltites are of oil origin and has been solidified in veins close to surface and the geochemical correlation and encountering to the oil seeps in crevices suggest similarities between the Şırnak area asphaltites and Raman–Dinçer oils.

Effect of Molten Caustic Leaching on Demineralization and Desulfurization of Asphaltite

Molten caustic leaching process is effective in reducing significant amounts of ash-forming minerals, pyritic sulfur, and organic sulfur from solid fossil fuels. The effect of leaching asphaltite samples from Seguruk and Harbul collieries of Sirnak and Silopi asphaltite fields (situated in the Southeast Anatolia region of Turkey) with molten sodium hydroxide and followed by mild acid on demineralization and desulfurization was investigated. The effects of alkali/asphaltite ratio, time, and temperature on the leaching efficiency were detailed, and the experimental results are presented here. Chemical demineralization and desulfurization of asphaltite samples using molten sodium hydroxide were investigated in the temperature range of 200°C–400°C. The percentage of demineralization and desulfurization increased with the increase in alkali/asphaltite ratio. The removal of total sulfur and ash increased with increasing leaching temperature and time. Most of the inorganic sulfur and a significant portion of the organic sulfur were removed.

Flash pyrolysis of Silopi asphaltite in a free-fall reactor under vacuum

Flash pyrolysis experiments on asphaltite samples were performed in a free-fall reactor under vacuum to determine the effects of pyrolysis temperature, feed rate and particle size. Maximum liquid yield of 13 wt.% was obtained in free-fall reactor under vacuum when the pyrolysis temperature was 700 °C, feed rate was 0.4 g min −1 and particle sizes were between 0.075 and 0.250 mm. The liquid products obtained at various pyrolysis conditions were analyzed by gas chromatography/mass spectrometer (GC/MS) and liquid products were classified as following: C5–C10, C11–C15, C16–C20 and C20+. The amount of saturated hydrocarbons decreased while the amount of unsaturated hydrocarbons increased with increase of temperature. While percent of C5–C10 unsaturated hydrocarbons continuously increased with increase of temperature, the percent of C11–C15 unsaturated hydrocarbons increased up to 750 °C and then started to diminish. Functional group analysis of solid residue was carried out using Fourier transform infrared spectrometry (FT-IR). The proximate analysis of solid residue indicated that percent of fixed carbon and ash increased with temperature.

Non-isothermal DSC and TG/DTG analysis of the combustion of Si̇lopi̇ asphaltites

In this research, non-isothermal combustion and kinetics of Silopi (Turkey) asphaltite samples were investigated by differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). A sample size of 10 mg, heating rates of 5, 10, 15 and 20°C min−1 were used in the temperature range of 20–600°C, under air atmosphere. Two reaction regions were observed in DSC curves. The first region is due to the evaporation of moisture in asphaltite sample whereas, release of volatile matter and burning of carbon is called the second region.

The Effect of Aqueous Caustic and Various Acid Treatments on the Removal of Mineral Matter in Asphaltite

In this present study, high mineral matter (ash) asphaltites from Silopi, Southeastern Anatolia, Turkey were investigated using aqueous sodium hydroxide followed by various mineral acids such as HNO3, HCl, H2SO4, and HF. The extraction with 5% NaOH followed by leaching with 10% H2SO4 plus 40% HF was the optimum approach for chemical cleaning of the asphaltite and the maximum degree of the demineralization was found as 59.56%. At the same time, the calorific value increased to 20.86% according to the original sample. In addition, the spectrometric analyses of treated asphaltite samples were performed by FTIR and X-ray diffraction.

DESULFURIZATION AND DEMINERALIZATION OF ASPHALTITE BY AQUEOUS CAUSTIC LEACHING

The method of desulfurization and demineralization by aqueous caustic leaching (ACL) was used for treatment of asphaltite samples from Seguruk collieries of Sirnak asphaltite fields, situated in Southeast Anatolia region of Turkey. The effect of different parameters such as alkali concentration, time and temperature on leaching efficiency was studied, and the experimental results are presented here. The concentration of caustic was varied from 0.1 to 1.0 M, temperature from 100 to 180 °C, and leaching time from 4 to 16 h. Elevation of alkali concentration, leaching temperature and prolongation of time increase the removal of total sulfur and ash. As a result of ACL, ash content of asphaltite was reduced from 40.08 to 22.14%, and 75% of combustible was recovered. Total sulfur and volatile matter content was reduced from 6.74 to 2.49% and from 33.72 to 19.10%, respectively.

The occurrence and potential origin of asphaltite in bedrock fractures, Forsmark, central Sweden

Occurrences of asphaltite in fractures in the Svecofennian basement have been documented in drill cores from the site investigation for a deep repository for nuclear waste in Forsmark, central Sweden. The carbonaceous material has been found at depths down to 124 m and appears as hardened black fracture fillings. The δ13C values of the asphaltite are relatively uniform with values between -29.5 and -30.1‰ (PDB) indicating an organic origin. These results are consistent with previous analyses of asphaltite occurrences in Sweden. One sample collected from a fracture in the Ordovician limestone in Kinnekulle, south-western Sweden was analysed for comparison and shows a similar δ13C signature (-29.5‰). Biomarker analyses of the asphaltite samples confirm an organic origin and the organic-rich early Paleozoic Scandinavian Alum Shale is suggested as the source rock. This is supported by comparison of the asphaltite with published biomarker and carbon isotopic data from the Alum Shale. Downward migration of hydrocarbons into the crystalline basement due to the presence of an overpressured basin is a possible mechanism for the emplacement of the asphaltite in the bedrock fractures. It is suggested that the heat source responsible for the migration of the asphaltite was the overburden of the Caledonian foreland basin.

Improvements on combustion properties of asphaltite and correlation of activation energies with combustion results

Processing of Şırnak Asphaltite sample by gravity and flotation concentration methods was investigated to decrease its ash content. Finely disseminated inorganic constituents of asphaltite revealed the difficulty of operation. Ash content of asphaltite was reduced from 44.86% to 31.44% by gravity concentration method with a 75% combustible recovery. On the other hand, it was possible to reduce ash content to 24% by flotation with almost same combustible recovery. Combustion characterization of raw and improved asphaltites was performed by non-isothermal thermogravimetric experiments. The data obtained were analyzed for the determination of activation energy of asphaltite samples. Processing proved to improve the combustion characteristics of asphaltite where activation energies showed the same trend with ash contents of asphaltite samples and decreased from 47.75 kJ/mol of raw asphaltite to 30.24 kJ/mol. As a result, activation energies were correlated with ash contents, calorific values, burn-out temperatures and sulfur contents of processed samples.

Ion irradiation of asphaltite as an analogue of solid hydrocarbons in the interstellar medium

We present the results of experiments of low temperature ion irradiation of pure asphaltite samples and those covered with water ice layers. Asphaltite (a natural bitumen) was used as an analogue of carbonaceous interstellar grains on which water- rich icy mantles can be formed in the dense and cold phases of the interstellar medium. We simulated irradiation by cosmic ions in the laboratory to study, by in situ infrared spectroscopy, the formation of molecular species in the asphaltite samples and at the interface between the refractory solid (asphaltite) and the water ice mantle. New molecular species were formed at the expense of water molecules and atoms (mainly carbon and hydrogen) from the asphaltite substrate. The vibration modes we detected at low temperature (16 K) include: C-H stretch (carbynoids), C-H asymmetric stretch (acetylene), C-H aromatic stretch, C=O stretch in CO2 ,C ≡O stretch in CO, and C≡C stretch (carbynoids). Some of these species remain stable after warming of the irradiated samples to room temperature.

OXIDATION STUDIES ON ŞIRNAK ASPHALTITES. DETERMINATION OF KINETIC PARAMETERS

Oxidation of Sirnak asphaltite samples was investigated under isothermal conditions using a fixed-bed reactor in various temperature modes. Combustion profiles were obtained by using a continuous gas analyzer. The rate data were analyzed based on the assumptions that oxidation reaction takes place on the surface of solid asphaltite particles and decomposition of organic structures is not significant. Oxidation rates were determined and constant overall order of reaction (1.7 ± 0.3) was established. The effect of heating rate on reaching final isothermal temperatures was investigated and kinetic parameters of the overall oxidation reaction for each heating rate determined.