Bitumen Recovery Research Articles

Enhanced bitumen extraction from oil sands using CO2-responsive surfactant combined with low-salinity brine: Toward cleaner production via CO2 utilization

With a recent concern on more sustainable production, oil sands as an affordable energy resource requires more efficient and cleaner technology to extract bitumen from its deposits. Recent study conceptualized the combination of greener bitumen recovery and CO2 utilization, which shows promising potential. Using CO2-responsive surfactants that could ‘switch’ the bitumen-water interfacial behavior, oil-water separation process can be greatly improved, although its workability in bitumen aeration stage and co-presence with brines are not yet fully examined. In the current study, influence of a combination of CO2-responsive surfactant and NaCl brine fluids to bitumen liberation and aeration stages were investigated. Two interfacial phenomena (i.e., bitumen-water interfacial tension and bitumen-water-substrate contact angle) were studied as dominant parameters to oil sands processing. Although an ultra-low interfacial tension at high mixture concentration (6 mM surfactant + 500 mM NaCl) promises an advantage for bitumen extraction via a spontaneous bitumen pinch-off, some bitumen residual was left unproduced on substrate. While the low-salinity brine at the same surfactant concentration (6 mM surfactant + 10 mM NaCl) resulted in a much-reduced bitumen-substate contact area, which could practically enhance bitumen liberation. Furthermore, CO2-responsive surfactant suggests a good switchability in such a high-salinity environment for bitumen-water demulsification, owing to the CO2-induced acidification. In aeration stage, CO2 bubble was found a greater ‘attachability’ to bitumen surface compared to typical air bubble. This observation suggests a promising CO2 utilization as an alternative flotation gas carrier for bitumen aeration. The findings in the current study provide fundamental guidance on bitumen extraction process enhanced by both surfactant and brine fluids. The study also confirms a holistic improvement for the whole extraction process with CO2 utilization toward a cleaner production that couples both climate action and affordable energy sustainable goals.

Carbon Dioxide Huff and Puff as Environmentally Friendly Method for Enhanced Heavy Oil Recovery

Heavy oil and bitumen are making up approximately 70 percent of the remaining estimated hydrocarbon reserves. Many Enhanced Oil Recovery (EOR) methods such as chemical flooding, thermal recovery, gas injection, etc., were developed to make advances in the production of unconventional oil. Among all the variety of EOR methods, thermal recovery produces practically all of the heavy oil and bitumen among the various EOR methods. But at the same time, throughout its application, there are several disadvantages were revealed such as it is an expensive and not environmentally friendly process, heat loss in surface facilities and distribution lines, the efficiency is low after injection, increases in the extracted oil’s surface viscosity have caused polymerization reactions of free radicals created during the steam injection process, and the requirement for continuous steam injection is attempting to keep a hot oil-water interface at the front of the flow. For these reasons, the solvent-based non-thermal recovery method can be used to enhance heavy oil and bitumen recovery in unconventional reservoirs (thin or deep reservoirs) to prevent or reduce unwanted effects as described above. Toluene, carbon dioxide (CO2), ethane, propane, normal butane, and mixture solvents, among others, can be used as the injection solvent for the solvent-based non-thermal recovery method. That is why the researchers have concentrated on carbon dioxide as a solvent with Huff & Puff method to develop the production of heavy oil and bitumen to overcome all these negative issues because CO2 has several characteristics that make it an excellent option for this application. In this paper, the CO2 Huff and Puff method is reviewed. The CO2 Huff and Puff method’s viscosity reduction and oil swelling procedures have been the most significant factors in increasing heavy oil production. As a results, impacts of oil swelling at various temperatures and pressures as well as the viscosity reduction ratio with CO2 injection have been studied.

Enhanced accumulation of bitumen residue in a highly concentrated tailings flow by microbubbles from in-situ catalytic decomposition of hydrogen peroxide

The massive volume of oil sands tailings has been one of the most challenging environmental issues. In this work, we experimentally explore a simple and effective approach to bitumen residue separation from a highly concentrated slurry flow of the artificial oil sands tailings. By utilizing microbubbles from in-situ catalytic decomposition of H2O2 at low concentrations, bitumen aggregation is enhanced on the top part of the hydrotransport pipeline. The microscopic image analysis revealed the in-situ formation of microbubbles and confirmed that magnetic particles present in the slurries contributed to the fast release of the gas products and bubble formation from hydrogen peroxide decomposition. A high-speed camera was applied to capture images of the tailings flow in the pipeline through a transparent view window. A large number of tiny bubbles were identified post to the injection of H2O2 to the slurry flow. More than 70 % bitumen could be recovered from a lab-scale pipeline loop within 30 mins after H2O2 injection. The bitumen recovery efficiency from the collected froth was quantitatively compared under seven conditions with varied dosages, the concentration of H2O2, and the amount of magnetic solids in the slurries. Our results confirmed that the total dosage of H2O2 is the dominant factor in in-situ microbubble formation for enhanced bitumen aggregation in the flow. Importantly, microbubbles were generated rapidly in the real mature fine tailings. The results from our study provide insights into the preferential distribution of oil residue in the flow during hydrotransport without the requirement for an additional device. Removal of oily residues from concentrated slurries may bring economical and environmental advantages.

Disposal From In Situ Bitumen Recovery Induced the ML 5.6 Peace River Earthquake

AbstractEarthquakes induced by human activities can impede the development of underground resources. Significant induced events (M5) have caused both economic and human losses. The recent ML 5.6 (MW 5.1) event near Peace River, Alberta occurs in a region of in situ bitumen recovery. We find that 3.4 cm of ground deformation was caused by reverse fault slip (∼29 cm), possibly related to Peace River Arch faulting. Events are located within the shallow basement, nearby to significant wastewater injection into Paleozoic strata. We find a statistical relationship between earthquakes and injection operations. These events were likely related to the in situ bitumen development: dominantly from wastewater disposal induced pore pressure increases, with smaller poroelastic contributions from bitumen recovery. The assessment of this earthquake as induced will likely have implications for future energy development, management, and regulation—including carbon capture and blue hydrogen.

Measurements and modeling of the exsolution and dissolution kinetics of methane and bitumen system at T = (353.15–433.15 K)

We present the first experimentally measured data set on the exsolution/dissolution kinetics of methane and bitumen system at the test temperature range of 80–160 °C, and a pressure difference of 0.69 MPa, between 1.81 MPa and 2.5 MPa. An analytical model is used to estimate the exsolution and dissolution diffusion coefficients for the methane/bitumen system from the acquired data set. The results revealed faster exsolution kinetics compared to dissolution for the methane-bitumen system. The exsolution and dissolution diffusion coefficients were found to be in the range of (1.13–14.2) × 10−8 m2/s and (1.95–56.9) × 10−9 m2/s, respectively. Furthermore, the experimentally measured diffusivity measurements were modeled using the Arrhenius-type relationship, and the analysis indicated higher activation energy for the dissolution of methane in bitumen compared to the exsolution. The reported exsolution and dissolution diffusivity measurements have applications in the design and simulation of the solvent-assisted thermal recovery of bitumen and heavy oil.

The impact of permeability barriers on steam-solvent coinjection – A mechanistic study using a physical model

Coinjection of steam and condensate has been studied for improving the energy efficiency of steam-assisted gravity drainage (SAGD) as solvent-assisted SAGD or SA-SAGD. However, it is not well understood how tortuous hydraulic paths under heterogeneous permeability can influence the compositional and thermal flow characteristics in SA-SAGD. We addressed this question by performing an experiment of the coinjection of steam and condensate for bitumen recovery. This paper discusses the experimental results and gives our mechanistic analysis of how the tortuous hydraulic paths affected the thermal and compositional flow and the properties of the produced bitumen in the experiment.The physical model was a cylindrical pressure vessel with a diameter of 0.425 m and a length of 1.2 m, which was filled with unconsolidated sands. Two shale plates were horizontally installed above the well pair at different elevations so that they could represent permeability barriers to cause tortuous flow paths during the SA-SAGD experiment. The porosity and permeability of the sandpack was 0.34 and 5.6 D, respectively. Initially, the oil and water saturations were 95% and 5%, respectively.After preheating for 1 day, a mixture of 98.2 mol% steam and 2.8 mol% condensate was injected at 3500 kPa for 4 days (35 cm3/min of steam, cold water equivalent). The injection and production histories along with the real-time temperature distribution were recorded during the experiment. Produced oil samples were frequently taken and analyzed for density and asphaltene content. After the experiment, the sandpack was excavated and sampled from different locations to analyze the saturation and asphaltene content of the remaining oil. The experimental results in this paper were compared with the previous SAGD and SA-SAGD experiments that used the same experimental set up with a homogeneous sandpack.Results showed that, in comparison to the homogeneous SAGD case, SA-SAGD was able to lower the cumulative steam-oil ratio (SOR) by a factor of two to three even in the presence of shale plates. Analysis of the temperature profiles indicated that the steam chamber vertically expanded from the lower part to the upper part through tortuous paths at lower temperatures. An emerging steam chamber above the shale plates occurred by convective heat from the injection well through lower-temperature flow paths between shale plates, involving light to intermediate solvent components that enabled the steam chamber to expand away from the injection well. This highlights the important role of volatile solvent components in the growth of a steam chamber in SA-SAGD under heterogeneity. The produced bitumen density in this research was closer to the original bitumen than in the homogeneous SA-SAGD case because the bitumen dilution and the solvent retention increased by the tortuous flow regime resulted in efficient drainage of oil at lower temperature.

Molecular Dynamics Investigation of Wettability Alteration of Quartz Surface under Thermal Recovery Processes.

One of the primary methods for bitumen and heavy oil recovery is a steam-assisted gravity drainage (SAGD) process. However, the mechanisms related to wettability alteration under the SAGD process still need to be fully understood. In this study, we used MD simulation to evaluate the wettability alteration under a steam injection process for bitumen and heavy oil recovery. Various oil droplets with different asphaltene contents were considered to determine the effect of an asphaltene content on the adsorption of the oil droplets onto quartz surfaces and wettability alteration. Based on the MD simulation outputs, the higher the asphaltene content, the higher the adsorption energy between the bitumen/heavy oil and quartz surfaces due to coulombic interactions. Additionally, the quartz surfaces became more oil-wet at temperatures well beyond the water boiling temperature; however, they were extremely water-wet at ambient conditions. The results of this work provide in-depth information regarding wettability alteration during in situ thermal processes for bitumen and heavy oil recovery. Furthermore, they provide helpful information for optimizing the in situ thermal processes for successful operations.

Gravity Drainage of Bitumen Induced by Solvent Leaching.

Steam-based thermal recovery processes are energy-intensive and pose environmental concerns due to their high greenhouse gas emissions. The application of solvents has shown promise in reducing the environmental impact of these processes. In this work, the solvent chamber theory is used to study the gravity drainage of bitumen. The results reveal that the drainage rate can be scaled using the thermophysical properties of solvents. The drainage rate is shown to be directly related to the density difference between bitumen and solvent and inversely proportional to the mixture viscosity. A universal scaling relation between the Sherwood number, as a measure of the mass transfer, and Rayleigh number, as a measure of the natural convection, in the form of Sh = βRa is presented using the experimental data of various solvents. This linear relationship is consistent with the theoretical studies of buoyancy-driven convection. Moreover, the scaling prefactor β is found to decrease with increasing natural log of the mobility ratio (α), which results in a lower rate of convective mass transfer. Furthermore, a new critical Rayleigh number equation based on the power-law mixing rule (PLMR) is derived, and the results are compared with the available theories in the literature based on the exponential mixing rule (EMR). The findings provide insights into understanding the convective dissolution with large viscosity contrast. Furthermore, the developed scaling relation provides a useful tool to predict the convective mixing of different bitumen/solvent systems. The results find application in the design of the solvent-based bitumen recovery processes.

Effect and Mechanism of Rejuvenation of Field-Aged Bitumen Extracted from Reclaimed Asphalt Pavement

Due to wear and exposure to atmospheric agents, road pavements are subject to an inevitable aging process. Asphalt rejuvenating agents implement the reorganization of the colloidal structure of aged bitumen as well as the restoration of the correct asphaltene/maltene ratio. In recent years, several incentives have been put in place regarding conservation of resources and safeguarding the environment by avoiding waste and promoting a circular economy. Reclaimed Asphalt Pavement (RAP) is one of the ways to promote and implement circular economy practices. Recovery of bitumen from RAP conglomerate is a viable way of recycling aged bitumen for use in new pavements. Aged bitumen binder from RAP however needs to be rejuvenated in order to restore its virgin properties for it to be suitable for new paving operations. This paper evaluates the effectiveness of a rejuvenating agent on reclaimed asphalt pavement through both the analysis of the mechanical modulus and the inner micro- structural of the samples. These were conducted through Dynamic Shear Rheology (DSR), Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC) and light microscopy.

Computational fluid dynamics investigation of bitumen residues in oil sands tailings transport in an industrial horizontal pipe

Pipeline transport is commonly used in the oil sand industry to convey crushed oil sand ores and tailings. Bitumen residues in the oil sand tailings can be a threat to the environment that separating them from tailings before disposal is crucial. However, low bitumen concentration in the tailing slurry and the complex transport characteristics of the four-phase mixture make the process difficult. This study establishes an Eulerian–Eulerian (E–E) computational fluid dynamics model for an industrial-scale oil sand tailings pipeline. A comprehensive sensitivity analysis was conducted on the selection of carrier-solid and solid-bitumen drag models. The combination of small and large particle sizes (i.e., 75 and 700 μm) and bitumen droplet size (i.e., 400 μm) provided good agreement with field data in velocity profiles and pressure drop. The validated model was subsequently extended to investigate the influence of the secondary phase (i.e., bitumen droplets and bubbles) on flow characteristics in a tailing pipeline. The investigation covered a range of bitumen droplet size (100–400 μm), bitumen fraction (0.0025–0.1), bubble size (5–1000 μm), and bubble fraction (0.0025–0.3) and their influences on the velocity, solids, and bitumen distribution are revealed. For an optimum bubble size of 500 μm, a maximum recovery of 59% from the top 50% and 83% from the top 75% of the pipe cross section was obtained. The present study demonstrates the preferential distribution of bitumen and provides valuable insight into bitumen recovery from an industrial-scale tailing pipeline.

Measurements and Modeling of the Dissolution and Exsolution Kinetics of the Ethane/n-Heptane System

Solvent-aided thermal recovery processes have been suggested and implemented to reduce the environmental impact of steam-based heavy oil and bitumen production. The injected solvents often undergo dissolution (exsolution) into (from) the oil phase throughout the heavy oil and bitumen recovery processes. New experimental data at elevated pressures and temperatures are essential to better understand the dissolution and dissolution kinetics of various solvents. To eliminate this gap, a new experimental setup was developed to study the kinetics of exsolution and dissolution of gases. The developed setup was used to study the exsolution of ethane from ethane-saturated heptane and the dissolution of ethane in heptane in a temperature range of 60 to 120 °C. An analytical model was adapted to model the experiments and estimate the diffusion coefficients of exsolution and dissolution of the ethane/heptane system. The results indicate that the exsolution of ethane from heptane is much faster compared to its dissolution. The molecular diffusion coefficients for exsolution and dissolution were found to be in the range of (2.02–5.44) × 10–6 and (1.76–11.80) × 10–8 m2/s, respectively. The measured experimental data were modeled using the Arrhenius-type kinetics. The results revealed lower activation energy for the exsolution of ethane from ethane-saturated heptane compared to its dissolution. The reported dissolution and exsolution data sets find applications in the design, simulation, and optimization of solvent-aided thermal recovery of bitumen/heavy oil and various chemical processes.

The effect of clay type and solid wettability on bitumen extraction from Canadian oil sands

Clays (<2 μm) in oil sands ores have a significant impact on the processability of the ores. The present study aims at understanding the effects of the type and wettability of clays on the performance of bitumen extraction from mined oil sands. The results from batch extraction tests showed a detrimental effect of doping with hydrophilic clays (kaolinite, illite and montmorillonite), with montmorillonite being the worst. The crucial role of clays in bitumen slime-coating was studied through atomic force microscopy and clay deposition tests. For the hydrophilic clays, clay concentration was an essential parameter in determining the bitumen-clay hetero-coagulation process. Strong slime-coating of clay particles on bitumen droplets occurred only above a critical clay concentration. This critical concentration varied with clay type and water chemistry. Compared with earlier studies, kaolinite was found to deposit strongly on bitumen surfaces for the first time in this study. Hydrophilic clays were contaminated by soaking in toluene-diluted-bitumen solutions to investigate the effect of solid hydrophobicity on bitumen extraction. Hydrophobic clays had a less significant depression on bitumen recovery but a more significant deterioration on froth quality than hydrophilic clays. Similar slime-coating was observed for the different clays once contaminated by diluted bitumen. Furthermore, the presence of a large content of clays in bitumen extraction could result in excessive emulsification of bitumen into small droplets, leading to low bitumen recovery. This work provides useful insights into the fundamental interactions of clays and bitumen, with implications for developing a viable solution in dealing with clays in oil sands operations.

Swelled Mechanism of Crumb Rubber and Technical Properties of Crumb Rubber Modified Bitumen.

Crumb rubber modified bitumen (CRMB) has excellent high-temperature performance and fatigue resistance, and is widely used in asphalt pavement to cope with increasing traffic axle load and changing climate. Under conventional preparation conditions, the swelling degree of CR can directly impact the comprehensive properties of CRMB; however, physical and chemical properties research on swelling crumb rubber (SCR) and crumb rubber recycled bitumen (CRRB) in CRMB is relatively lacking. In this paper, the working performance of CRMB and CRRB in high-temperature and low-temperature conditions were studied through physical and working performance testing of bitumen. The CR and SCR were tested by scanning electron microscope (SEM), Fourier transform infrared spectrometer (FTIR), gel permeation chromatography (GPC), and particle size distribution (PSD) tests to study the physicochemical behavior and microscopic effects before and after CR swelling. The results showed that CR dosage was in the range of 10%, 15%, and 20%, as well as that CR dosages have a positive effect on the high- and low-temperature performance, storage stability, and elastic recovery of bitumen. The high-temperature PG grades of bitumen were directly improved by four grades, and the elastic recovery rate increased by 339.9%. CR improved the ultra-low temperature crack resistance of bitumen. Due to the absorption of lighter components by CR, the relative content of the heavy component of bitumen increased; however, its low-temperature performance decreased significantly. After swelling, the CR particle size increased and the range became wider, the surface complexity of CR became higher, and the specific surface area was larger. At the same time, CR carried out the transformation process from large and medium molecules to small molecules. During the swelling process, a new benzene ring structure appeared in the CR, and the C-C bond and C-S bond of CR broke, forming part of the C=C bond.

Design and construction of a continuous pilot flotation facility: A case study for water-based oil sand extraction

In this work, the design and construction of a continuous and pilot-scale flotation facility are demonstrated. The performance of the new facility was evaluated from series of pilot flotation tests, carried out using oil sands slurry to extract bitumen—an extra-heavy form of petroleum. Results indicated that bitumen recoveries of the new pilot plant for an identical ore and water chemistry were largely dependent on air injection method, slurry conditioning time, flotation residence time, and slurry temperature. Importantly, when compared with those of bitumen extraction tests using a bench-scale Batch Extraction Unit (BEU) operated at the most optimal conditions, it was suggested that the new pilot plant produced flotation recoveries of bitumen and froth qualities at a level as good as, or even higher than, the level accomplished using the BEU at an identical ore, water chemistry and operating temperature. This continuous, pilot flotation plant could potentially serve as a pre-commercial production system that verifies a new processing aid, or as an alternative extraction technology for oil sand, coal, and mineral processing.

A semi-compositional approach to model asphaltene precipitation and deposition in solvent-based bitumen recovery processes

Steam assisted gravity drainage (SAGD), as a commercially proven high ultimate recovery process for heavy oil and bitumen is energy intensive and may be limited by high usage of water. In the recent years, numerous methods to combine solvent and heat have been proposed for the in-situ recovery of bitumen. Among these methods, N-Solv (heated solvent vapor injection) and EBRT (enhanced bitumen recovery technology) utilize heated solvent vapor to extract heavy crudes under in situ conditions. These methods take the advantage of partial in situ upgrading of oil with much lower consumptions of water and natural gas and have the potential to reduce greenhouse gas (GHG) emissions. However, with the current knowledge relevant to solvent/heat-assisted recovery processes, it still remained uncertain how the in-situ upgrading could impact ultimate recovery and the efficiency of these processes. This study, thus, aims at providing insights about these processes with a numerical model. The study develops a simulation model that captures important mechanisms involved in the processes such as diffusion/dispersion, solvent dissolution, asphaltene precipitation and potential deposition. The complexity of modelling such processes is due to interrelation of oil–gas phase behavior and fluid transport mechanisms combined with in situ upgrading of oil. The intention is not to only identify factors important to the modeling of these processes, but also find how robust simulation models can be developed to replicate observed field behavior. A semi-compositional approach, based on liquid–liquid equilibrium, is proposed to properly capture the asphaltene precipitation in thermal numerical simulators using direct lab measured data. Our analysis will be presented regarding upgrading mechanisms that should be implemented, their effect on the oil production rate, and techniques to model them.

High‐efficiency separation of oil sands using ChCl‐based deep eutectic solvents

AbstractDeep eutectic solvents (DESs) are a kind of potential lixiviant for extraction processing. Unlike conventional ionic liquids (ILs), DESs are relatively cheap and environmentally friendly. Herein, three different ChCl‐based DESs, namely, choline chloride/urea, choline chloride/ethylene glycol, as well as choline chloride/propandioic acid, were synthesized and used to enhance bitumen recovery from oil sand by petroleum ether extraction. The results showed a multiphase system formed after mixing the components at ~25°C, consisting of sands and clays, a DES layer, and a petroleum ether layer containing the bitumen. These DESs were immiscible with bitumen or petroleum ether. Coupled with a density difference, a clear phase separation was presented between the bitumen–petroleum ether mixture and DES. The DES functioned as a separating agent, keeping the petroleum ether–bitumen mixture and spent sand apart from each other. The results showed that the bitumen recovery was increased by ~12% compared with that without the DESs. We deduced that the enhancement in the separation may result from the reduction of adhesion between bitumen and sand by the DESs. The ChCl‐based DESs and petroleum ether could be readily recycled to reduce industrial costs. After 10 cycles, the bitumen recovery remained above 86%.

Asphaltene Precipitation Prediction during Bitumen Recovery: Experimental Approach versus Population Balance and Connectionist Models.

Deasphalting bitumen using paraffinic solvent injection is a commonly used technique to reduce both its viscosity and density and ease its flow through pipelines. Common modeling approaches for asphaltene precipitation prediction such as population balance model (PBM) contains complex mathematical relation and require conducting precise experiments to define initial and boundary conditions. Machine learning (ML) approach is considered as a robust, fast, and reliable alternative modeling approach. The main objective of this research work was to model the effect of paraffinic solvent injection on the amount of asphaltene precipitation using ML and PBM approaches. Five hundred and ninety (590) experimental data were collected from the literature for model development. The gathered data was processed using box plot, data scaling, and data splitting. Data pre-processing led to the use of 517 data points for modeling. Then, multilayer perceptron, random forest, decision tree, support vector machine, committee machine intelligent system optimized by annealing, and random search techniques were used for modeling. Precipitant molecular weight, injection rate, API gravity, pressure, C5 asphaltene content, and temperature were determined as the most relevant features for the process. Although the results of the PBM model are precise, the AI/ML model (CMIS) is the preferred model due to its robustness, reliability, and relative accuracy. The committee machine intelligent system is the superior model among the developed smart models with an RMSE of 1.7% for the testing dataset and prediction of asphaltene precipitation during bitumen recovery.

Ultrasonic extraction of oil shale bitumen and study of its structural features using GC-MS and NMR techniques

ABSTRACT Oil shale is a raw material that is considered to be an alternative fossil fuels and it is widely used in producing energy and chemicals. Oil shale bitumen identification are not widely described in literature. This article tackles the structural elucidation of oil shale bitumen using gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) spectroscopy with a short sample preparation step, based on ultrasonic-assisted liquid extraction. The ultrasonic-assisted extraction was examined in terms of solvent type and volume, sample size, sonication time and temperatures. A bitumen recovery of 17.7 wt% dmmf (dry-mineral-matter-free) was achieved when 0.50 g of shale was mixed with 20 mL THF and sonicated for 10 min at ultrasonic power of 120 W at 45°C. GC-MS of the bitumen showed high polar oxygenated compounds with more than 20 wt% being esters and ethers. Small concentrations of thiols and amides have been also found. The structural identification of bitumen was carried out using 1H-NMR and 13C-NMR and the results showed highly aliphatic character bitumen, consisting of aromatic, paraffinic, naphthenic and olefinic hydrogen and carbon atoms. These results suggested that ultrasonic solvent extraction could be an efficient and environment-friendly method for obtaining of bitumen from oil shale.

BIOPOSITIVE TECHNOLOGIES FOR HANDLING BITUMEN-CONTAINING CONSTRUCTION WASTE

The article discusses various biopositive technologies for handling bituminous waste based on roofing materials after the loss of their operational properties. The processes occurring during the thermal destruction of such materials in synchronous thermal analysis with the study of degradation products are considered. The effectiveness of the use of plasma technologies in the treatment of bitumen - containing waste has been studied and it has been established that the ratio of the mass of waste material to solid residue ash reaches 400:1, thus the degree of processing is more than 99,7 %. The authors proposed an alternative technology that allows the use of bitumen contained in the waste of waterproofing materials as an organic raw material for further use in the construction industry. Considered is the chemical recovery of bitumen using various organic solvents, such as technical kerosene, carbon tetrachloride, chloroform and trichlorethylene. According to the calculated indices of correspondence of the chemical composition, it was established that carbon tetrachloride is the most effective solvent. The chemical composition of the bitumen extracted with this solvent is closest to the control sample taken without the participation of solvents.

Effect of Steric Hardening on the Damage Recovery of Bitumen

Effect of Steric Hardening on the Damage Recovery of Bitumen