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The production process of the traditional paper making process produces a large amount of waste water, known as paper black liquor. It is needed to explore new ways of reusing this waste and replacing part of the base bitumen to reduce the consumption of non-renewable resources, such as petroleum, thus obtaining better environmental, economic, and social benefits. This paper analyses the feasibility of using paper black liquor, which contains a large amount of lignin, as a modifier for bitumen in the paper industry. Samples of modified bitumen were prepared with 15%, 30%, and 45% of the base bitumen replaced by paper black liquor, and a control group of base bitumen was prepared for testing. The samples were subjected to an 85 min short-term ageing test, FTIR scanning test, thermogravimetric test, frequency scanning test, MSCR test, and LAS test. The analysis of the FTIR and thermogravimetric tests showed that the paper black liquor was mainly composed of lignin and some cellulose, and contained a small amount of salts with Na ions; based on the results of the frequency scan, the compatibility analysis of the vGP curve showed that the modified bitumen was more compatible in the high-temperature range after short-term ageing, thus inferring that the water content of the concentrate had an influence on the compatibility, making it necessary to further investigate different optimum water contents to achieve the best performance and benefit. The incorporation of paper black liquor improved the rutting resistance and fatigue resistance of the modified bitumen, and also gave the paper-black-liquor-modified bitumen a better ageing resistance than the base bitumen. While demonstrating the feasibility of using paper black liquor as an bitumen modifier, this study also helps to provide a basis for theoretical applications of biomass materials in the field of road engineering. [ABSTRACT FROM AUTHOR]

Scientists have effectively demonstrated that the introduction of a waste product comprising cementitious chemical compositions can enhance the mechanical properties and durability of cold bitumen emulsion mixes (CBEMs). On the other hand, the high air void content of the CBEM mix remains a challenge that is considered unsatisfactory by paving engineers. As a result, this investigation highlights two major changes that were made. The first is the use of waste paper sludge ash (PSA) as a filler in CBEM instead of the conventional mineral filler (CMF). The second change was made to further improve the mixture by reducing the amount of CBEM air voids using microwave (MW) heating energy as a post-treatment method. When compared to typical hot mix asphalt (HMA), the new CBEMs showed great mechanical properties and durability. Moreover, the proposed method, using CBEMs, has lower environmental risks, is safer, and is more cost-effective than existing paving mix technologies. This study presents a method for controlling air voids within pavement specifications without affecting mechanical behaviour or generating additional environmental or economic considerations. When compared to typical mixtures, laboratory test results showed that MW-heating can enhance both the stiffness modulus and the air void content. Furthermore, these results revealed a minor reduction in creep stiffness and water sensitivity. Nevertheless, in terms of mechanical, volumetric, and economic properties, the suggested post-mix treatment was comparable to HMA. The findings point to the need to adopt CBEM post-heating approaches, particularly the MW treatment procedure. [ABSTRACT FROM AUTHOR]

In this study, a critical evaluation and the benefits of using a waste and a virgin polymer in an asphalt mixture are presented. The present paper is the result of a three-year research effort to find a suitable recyclate compatible with asphalt binder and setting reaction conditions in the preparation of asphalt mixtures with the mentioned recyclate. This suitable candidate was recycled low-density polyethylene (LDPE), which was produced by recycling old, worn-out bags and films. An amount of 6% of LDPE by the weight of the binder content was suggested as the best amount of the modifier. Physical tests, including penetration, softening point, and kinematic viscosity have been carried out to prove the effectiveness of the modification on the binder properties. The effectiveness of the blending process and the appropriate concentration of additives led to a homogeneous polymer-modified bitumen without any imperfections in the structure. After successful preparation under laboratory conditions, this paper describes the preparation of asphalt mixtures directly in an asphalt-mixing plant and the subsequent implementation of a verification section. The overall composition of prepared polymer-modified asphalt mixtures has been studied. An important result of this study is the preparation of the asphalt mixture with waste LDPE that meets all the technical requirements. Moreover, it has been proven that this type of waste PE is fully applicable in asphalt-mixing plants in Slovakia, with zero or minimal financial burden on construction companies to complete the construction of their production facilities. Using such a technology, we can reduce the amount of waste plastics that otherwise end up in landfill. [ABSTRACT FROM AUTHOR]

Bitumen membranes have a primarily waterproofing function in the construction industry. The waterproofing function in bitumen membranes is provided by the mas of bitumen. The amount of bitumen mass can be determined by various methods. This paper deals with the determination of the bitumen mass in bitumen membranes by means of extraction and calcination. In the current legislation, the quantity of bitumen mass can only be determined by extraction. The calcination method is specified in the forthcoming EN 544, which is used for bitumen shingles. Previous research by the author has shown that the methodology from this standard cannot be used. The aim of this paper is to provide a practical verification of the extraction and calcination methods from previous author's research on a set of selected bitumen membranes. A total of 6 bitumen membranes were used for comparison. The bitumen membranes were of the same type from different manufacturers. The bitumen membranes were extracted in xylene. Calcination was carried out at 600°C. Two claims were made that confirmed the results of previous research on the bitumen coating and bitumen membranes. The first claim was that the calcination method is as time consuming or faster. This claim was confirmed. The second claim was that the results between extraction and calcination would differ by a maximum of 1.3%. The second claim was only partially met because the two asphalt strips contained insoluble but burnable parts. The results therefore differed by more than 1,3 %. [ABSTRACT FROM AUTHOR]

Physical and chemical indicators of bitumen quality of grade BND 70/100 with the added carbon nanopowder 2% by weight have been studied by laboratory test methods and analysis. High reaction ability of nanopowder particles and concentration of excess surface and internal energy in them have been determined, which provide the increase of low-temperature resistance, aggregate strength, and improvement of rheological properties of nanostructured bitumen. Essential structure variation has been proved: the increase of asphaltenes and oils content for 9% and 7.2% respectively due to the decrease of resins for 16.2% by weight. Methods have been discussed for preparing a liquid nanocarbon mix, adding of the mix into bitumen and homogenization of the bitumen. Some economic indicators have been represented which influence essentially the reduction for the cost value of the nanostructure bitumen. [ABSTRACT FROM AUTHOR]

The proportion of reclaimed asphalt pavement (RAP) bitumen that gets activated and coats the virgin aggregate during the initial stage of plant production of RAP mixes, in which the RAP material is initially mixed with superheated virgin aggregate, designated as the degree of RAP bitumen activity (DoA), is an important parameter influencing the quality and performance of the RAP mix. DoA is influenced by a variety of mix and process parameters. This paper presents an empirical model, developed using the results from a previous experimental investigation and those obtained from the additional experiments conducted in the present investigation, for prediction of the DoA of RAP binder under varying combinations of mix and process variables. The experimental investigation involved mixing separately identifiable size fractions of RAP material (1.18 to 4.75 mm) and virgin aggregate (9.5 to 26.5 mm) and measuring the quantity of RAP bitumen transferred to virgin aggregate to estimate the DoA. The 41 sets of experimental data considered for the development of the empirical model covered different RAP material proportions (15% to 75%), RAP binder quality (softening point of 69°C to 78°C), RAP binder content (4.0% to 6.0%), mixing duration (0.5 to 3 min), mixing temperature (70°C to 180°C), and superheating temperature of virgin aggregate (155°C to 197.5°C). The gradation and shape of the RAP material used in different coating experiments were also different. Additional experiments were carried out in the present investigation to study the effect of superheating temperature of virgin aggregates. DoA decreased exponentially with RAP bitumen stiffness and RAP content, whereas it increased with mixing temperature, mixing time, RAP bitumen content, and the proportion of coarser RAP material. The superheating temperature of virgin aggregate did not affect DoA significantly. A regression model was developed for estimation of DoA with reasonable accuracy without having to carry out the coating experiments. Such a predictive model is useful for obtaining inputs for the estimation of the quality of final binder blend in the RAP mix. [ABSTRACT FROM AUTHOR]

New requirements for the operational reliability of roads make the utilization of polymer-modified bitumen (PMB) more common in road construction. The application of polymer-modified bitumen based on traditional technology for the production of asphalt mixtures is associated with technological and economic difficulties and does not provide proper adhesion to the mixture's mineral components. In addition, the method of producing a binder over a long time at high process temperatures leads to increased aging, which significantly reduces the service life of the material in the pavement. This paper presents the results of studies on the effect of polymer–bitumen concentrate (PBC) consisting of styrene–butadiene–styrene, plasticizer, and surfactant on the bitumen characteristics. It has been established that the use of PBC in the bitumen binder leads to an increase in the temperature range of plasticity, softening temperature, elasticity, and cohesive strength with a decrease in the viscosity of the modified bitumen. With a complex modifier rational content of 8% by weight of bitumen, the temperature range of plasticity is 79 °C, and elasticity is 82%, which exceeds the parameters of the factory PMB-60 based on SBS polymer. Tests of binders using the Superpave method allow classifying the modified binder to the PG 64-28, which shows an increase in the temperature range of viscoelastic properties by 6 °C compared with the binder produced by traditional methods. Thus, the expediency of using a complex additive containing a polymer and surface-active substances (surfactants) that can be distributed in bitumen without the use of a colloid agitator and plasticizer has been proven to improve the quality of an organic binder. [ABSTRACT FROM AUTHOR]

Thermal recovery techniques for producing oil sands have substantial environmental impacts. Surfactants can efficiently improve thermal bitumen recovery and reduce the required amount of steam. Such a technique requires solid knowledge about the interaction mechanism between surfactants, bitumen, water, and rock at the nanoscale level. In particular, oil sands ores have extremely complex mineralogy as they contain many clay minerals (montmorillonite, illite, kaolinite). In this study, molecular dynamics simulation is carried out to elucidate the unclear mechanisms of clay minerals contributing to the bitumen recovery under a steameanionic surfactant co-injection process. We found that the clay content significantly influenced an oil detachment process from hydrophobic quartz surfaces. Results reveal that the presence of montmorillonite, illite, and the siloxane surface of kaolinite in nanopores can enhance the oil detachment process from the hydrophobic surfaces because surfactant molecules have a stronger tendency to interact with bitumen and quartz. Conversely, the gibbsite surfaces of kaolinite curb the oil detachment process. Through interaction energy analysis, the siloxane surfaces of kaolinite result in the most straightforward oil detachment process. In addition, we found that the clay type presented in nanopores affected the wettability of the quartz surfaces. The quartz surfaces associated with the gibbsite surfaces of kaolinite show the strongest hydrophilicity. By comparing previous experimental findings with the results of molecular dynamics (MD) simulations, we observed consistent wetting characteristics. This alignment serves to validate the reliability of the simulation outcomes. The outcome of this paper makes up for the lack of knowledge of a surfactant-assisted bitumen recovery process and provides insights for further in-situ bitumen production engineering designs. [ABSTRACT FROM AUTHOR]

This paper evaluates the strength performance of hot mix asphalt produced with High Density Polyethylene (HDPE)-modified bitumen and Reclaimed Asphalt Pavement (RAP) which is partially replacing virgin aggregates. Asphalt Institute blending chart was used to determine the quantity of Reclaimed Asphalt Pavement (RAP) incorporated into the mixture. Thermo-gravimetric Analysis and Differential Thermal Analysis (TGA/DTA) were used to determine thermal stability of the High Density Polyethylene (HDPE). Fourier Transform Infrared (FTIR) was used for characterization of the HDPE, bitumen and modified bitumen. Physical test conducted on the RAP and virgin aggregates in accordance with American Society of Testing Materials (ASTM) standards revealed that the aggregates are adequate for use in asphalt production. Marshall method of mix design was adopted for the hot mix asphalt production and testing. With respect to the threshold, the results of Marshall stability showed a 6% increase in the strength of the asphaltic mixture modified with 10% High Density Polyethylene (HDPE). Other Marshall properties tested also showed improvements. Scanning Electron Microscopy and Energy Dispersive X-ray Spectrometry (SEM/EDS) were used for micro-structural examination and composing elements analysis of the asphaltic mixture, respectively. Fibermetric analysis was used to explore the fiber content and pores within the mixture. [ABSTRACT FROM AUTHOR]

This study examines the applicability of an unknown composition waste plastic bag sample as bitumen modifier. The waste components were initially characterized to identify the type of plastics and the level of impurity. Asphalt binder performance was examined for rutting, thermal, and age resistance. The results revealed that the waste plastic bags, predominantly consisted of Low-Density Polyethylene (LDPE) and Linear Low-Density Polyethylene (LLDPE) and contained 6.1% impurities. The binder tests indicated that the waste plastic bags enhanced the rutting resistance of bitumen by one grade, with its modification more similar to LLDPE, rather than LDPE. The thermal degradation and aging properties of the modified binders demonstrated that the bitumen modified by the waste plastic bags exhibited slightly lower resistance to temperature and aging compared to virgin LDPE and LLDPE. This was attributed to the impurities contained in the waste plastic. In conclusion, the analyzed waste plastic bags proved to be suitable for use in binder modification, presenting a viable alternative to virgin LLDPE. [ABSTRACT FROM AUTHOR]

In recent times, circular economy initiatives in addition to the need for sustainable biomaterials have brought about several attempts at the eco-friendly, eco-sustainable and cost-effective production of asphalt pavements. It is an increasingly common practice in the asphalt industry to improve road pavement performance using additives to enhance the physico-chemical properties of bitumen, which performs the role of the binder in the asphalt mix. This paper evaluated the potential of a bio-based additive derived from olive leaf residue as a modifier and antioxidant agent for bitumen. Samples of neat, aged and doped aged bitumen were analyzed. In this study, the two bio-based additives were characterized in terms of phenol, chlorophyll, lignin and cellulose content, which was correlated with the mechanical properties of the tested samples. The mechanical properties of the neat, modified, aged and unaged samples were evaluated via Dynamic Shear Rheology. The bio-based additives proved to be promising and can improve the properties of bitumen binder and the performance of asphalt pavements in general. [ABSTRACT FROM AUTHOR]

Improving the aging resistance of waterproof membranes is very important to extend their service life. In this paper, organic montmorillonite (OMMT) was used to enhance the aging resistance of styrene-butadiene-styrene (SBS) modified bitumen (SMB) for waterproofing. The effect of OMMT on the physical properties, chemical structure, and micromorphology of SMB membranes before and after heat aging were investigated, and the service life of the SMB membranes was predicted based on the Arrhenius model. The results indicated that the high- and low-temperature performance of SMB was improved due to the addition of OMMT, and the optimal dosage of OMMT was 3%. After 20 days of heat aging at 80°C, the alterations of softening point increment, low-temperature flexibility decrement, and viscosity aging index of OMMT/SMB decreased by 1.5°C, 3°C, and 14.7%, respectively, compared with that of SMB, which indicated that OMMT can enhance the aging resistance of SMB waterproof membranes. Fourier-transform infrared spectroscopy indicated that the change of IC═O , IS═O , and IC═C of 3% OMMT/SMB was 53.5%, 45.6%, and 53.2% less, respectively, than SMB after 20 days of heat aging at 80°C, which shows that OMMT can inhibit the change of carbonyl, sulfoxide, and butadiene double bonds of SMB. The gel permeation chromatography showed that OMMT can hinder the degradation of SBS and polycondensation of bitumen during heat aging. The fluorescence microscope showed that OMMT/SMB maintained a more complete network structure than SMB after heat aging. According to the Arrhenius model, based on the 0°C flexibility as the damage point and the temperature of waterproof materials under sunlight being 60°C for an annual sunshine time of 1,200 h, the service life of SMB and OMMT/SMB were predicted to be 16.90 and 21.32 years, respectively. [ABSTRACT FROM AUTHOR]

Non-renewable nature and continuously increased consumptions of bitumen is a serious challenge for the development of infrastructure, especially for the constructions and maintenances of asphalt pavements. To cope with this situation, some sustainable strategies are needed. Extensive efforts have been made to improve the resilience, sustainability and circularity of asphalt pavements. Among them, the utilisation of bio-based materials is one of the most promising measures. This paper systemically reviewed the state-of-theart knowledge in the development of bio-bitumen. Wood-based oils, waste cooking oils and manure-based bio-bitumen were selected as the review objectives. It was revealed that all bio-based oils currently being used are more suitable for serving as additives like softeners, rejuvenators, or modifiers rather than as alternative of binders. One of the most promising utilisations of biooils is as rejuvenators, potentially antioxidants as well. Incorporating polymers with bio-oils is another feasible practice to improve the performance of biobitumen. Causation should be taken when producing bio-based bitumen since compatibility might have some kind of influence on the performance and this issue should be addressed carefully. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to present the development of a new predictive model intended for the calculation of stiffness modulus |E*| determined by a four-point bending beam test (4PBB or 4PB-PR). The model developed, called model A, was based on the Witczak model, which was developed for the dynamic-modulus (DM) method. Most of the asphalt mixtures used to develop the model were high-modulus asphalt concrete (HMAC). The most commonly used methods for determining the stiffness modulus |E*| of asphalt mixtures were also discussed. The paper presents the results of the study for 10 asphalt mixtures but 8 of them were used to develop the predictive model. In addition, the results of complex shear modulus G* tests on neat and modified bituminous binders carried out in a dynamic shear rheometer (DSR), necessary for the development of a predictive model, are presented. The tests carried out in the dynamic shear rheometer had significant measurement uncertainties. The results of the volumetric parameters of the asphalt mixtures are also reported. The developed model A has maximum absolute errors e = 1930 MPa (p = 95%) and maximum relative errors re = 50% (p = 95%). The distribution of the absolute errors of the model, after discarding outliers, has a normal distribution as in the development of other models of this type, which was confirmed by appropriate statistical tests. On the basis of the tests and calculations carried out, it was concluded that, in order to increase the precision of the predictive models, it is advisable to reduce the measurement uncertainty of the bitumen complex shear modulus G*. For the developed model A, the limiting values of the stiffness modulus |E*| are also shown, within which the determined stiffness modulus should fall. [ABSTRACT FROM AUTHOR]

Conventional bitumen pavement is no longer suitable for handling increasing loads and weather variations, which cause road deterioration, Thus, the modification of bitumen has been suggested to counter this issue. This study provides a detailed assessment of various additives for modifying natural rubber-modified bitumen used in road construction. This work will focus on the use of additives with cup lump natural rubber (CLNR), which has recently started to gain attention among researchers, especially in rubber-producing countries such as Malaysia, Thailand and Indonesia. Furthermore, this paper aims to briefly review how the addition of additives or modifiers helps elevate the performance of bitumen by highlighting the significant properties of modified bitumen after the addition of modifiers. Moreover, the amount and method of application of each additive are discussed further to obtain the optimum value for future implementation. On the basis of past studies, this paper will review the utilisation of several types of additives, including polyphosphoric acid, Evotherm, mangosteen powder, trimethyl-quinoline and sulphur, and the application of xylene and toluene to ensure the homogeneity of the rubberised bitumen. Numerous studies were conducted to verify the performance of various types and compositions of additives, particularly in terms of physical and rheological properties. In general, additives enhance the properties of conventional bitumen. Future research should investigate CLNR because studies on its utilisation are limited. [ABSTRACT FROM AUTHOR]

Enhanced oil recovery (EOR) processes are technologies used in the oil and gas industry to maximize the extraction of residual oil from reservoirs after primary and secondary recovery methods have been carried out. The injection into the reservoir of surface-active substances capable of reducing the surface tension between oil and the rock surface should favor its extraction with significant economic repercussions. However, the most commonly used surfactants in EOR are derived from petroleum, and their use can have negative environmental impacts, such as toxicity and persistence in the environment. Biosurfactants on the other hand, are derived from renewable resources and are biodegradable, making them potentially more sustainable and environmentally friendly. The present review intends to offer an updated overview of the most significant results available in scientific literature on the potential application of biosurfactants in the context of EOR processes. Aspects such as production strategies, techniques for characterizing the mechanisms of action and the pros and cons of the application of biosurfactants as a principal method for EOR will be illustrated and discussed in detail. Optimized concepts such as the HLD in biosurfactant choice and design for EOR are also discussed. The scientific findings that are illustrated and reviewed in this paper show why general emphasis needs to be placed on the development and adoption of biosurfactants in EOR as a substantial contribution to a more sustainable and environmentally friendly oil and gas industry. [ABSTRACT FROM AUTHOR]

This paper analyses the key findings of a study devoted to PET-modified bitumen. The research program was run according to the D-optimal experimental plan based on a factorial design. Five factors, i.e., the type of polymer (source), the type of bitumen (qualitative factors), PET amount, mixing rate, and mixing temperature (quantitative factors), controlled the bitumen–polymer mixing process. The experiment included a series of determinations of bitumen's rheological characteristics obtained by MSCR (Jnr, R) and G*/sin(δ) at 50 °C, 60 °C, and 70 °C. The low-temperature properties of the composite (critical temperature) were evaluated using a BBR test. The findings showed that bitumen modification with PET primarily reduced the creep susceptibility of the bituminous–polymer mixture. The low-temperature characteristics of the modified bitumen played a secondary but essential role. The amount of polymer and the mixing rate interacted with the temperature, significantly reducing the stiffness of the composite, while the type and amount of bitumen had a substantial effect on the results obtained in the BBR test. It is worth noting that when combining bitumen and plastomer, special attention should be paid to ensuring a high level of homogeneity of the mixture by controlling the parameters of the mixing process accordingly. The tests and analyses provided crucial models (GLM), which allowed for the prediction of the plastomer-modified bitumen's low- and high-temperature properties. The resulting relationships between factors and the identification of their impact on the bitumen properties enable a better understanding of the process of bitumen modification with PET. The conclusions presented here serve as a basis for future optimisation of the modified bitumen composition. The performed studies indicate that the use of >3% plastomer in bitumen 70/100 allows for a reduction in its susceptibility (MSCR) to below 0.5 kPa−1, making it suitable for bituminous mixtures for high-traffic roads. No significant increase in critical temperature (BBR) was observed. [ABSTRACT FROM AUTHOR]

A fast-melting styrene-butadiene-styrene-based modifier (SBS-T) was applied for rapid modification for asphalt mixtures. No relevant studies are available to support the effect of this new fast-melting modifier on asphalt-aggregate adhesion properties, and this paper is to remedy the assessment of the adhesive properties of the modified SBS modifier in asphalt mixtures. At the micro-scale, the sessile drop method is utilized to measure the contact angle of bitumen and aggregate and to compute thermodynamic parameters based on surface energy theory. Meanwhile, the effects of short-term and ultraviolet (UV) aging on the thermodynamic parameters of SBS-T modified asphalt (SBS-T-MA) were investigated. The asphalt-aggregate adhesion properties were further verified on a macro-scale scale by pull-off tests. The outcomes suggested that the higher the dosage of SBS-T modifier, the better the thermomechanical characteristics of the bitumen binder. The adhesive properties of SBS-T-MA and aggregates were promoted in short-term aging and decreased in UV aging. Statistical analysis of the pull-off test indicated a significant correlation between pull-off strength and energy ratio. It was demonstrated that adhesion damage occurred between asphalt and aggregate in the pull-off test and that the greater the energy ratio between asphalt and aggregate, the greater the asphalt-aggregate pull-off strength. [ABSTRACT FROM AUTHOR]

Petroleum asphaltenes are considered the most irritating components of various oil systems, complicating the extraction, transportation, and processing of hydrocarbons. Despite the fact that the paramagnetic properties of asphaltenes and their aggregates have been studied since the 1950s, there is still no clear understanding of the structure of stable paramagnetic centers in petroleum systems. The paper considers the possibilities of various electron paramagnetic resonance (EPR) techniques to study petroleum asphaltenes and their solubility fractions using a carbon-centered stable free radical (FR) as an intrinsic probe. The dilution of asphaltenes with deuterated toluene made it possible to refine the change in the structure at the initial stage of asphaltene disaggregation. From the measurements of samples of bitumen, a planar circumcoronene-like model of FR structure and FR-centered asphaltenes is proposed. The results show that EPR-based approaches can serve as sensitive numerical tools to follow asphaltenes' structure and their disaggregation. [ABSTRACT FROM AUTHOR]

Nowadays in the world, due to the constant desire for recycling, many countries are considering the use of recycled plastics on roads. Modification of bitumen for roads in Kazakhstan is considered one of the most suitable and popular approaches. This paper presents the results of research on the modification of bitumen by recycled plastics from waste materials. The paper describes the details of the use of plastic waste as bitumen modifiers, with a specific focus on recycled plastics and how they can potentially be used to enhance bitumen performance and the road durability. The main physical and mechanical characteristics of the modified bitumen were determined after routine tests, penetration and plasticity, softening temperature, brittleness temperature on Fraas and microscopic analysis. The morphology of the modified bitumen was studied using scanning electron microscopy. The results confirm that the modified bitumen complies with the requirements for polymer-bitumen binder of Kazakhstani standards and is suitable for the production of modified bitumen by its physical and chemical characteristics. [ABSTRACT FROM AUTHOR]

In recent years, the research on bitumen has reached the nanometer level, but there are still some problems in the study of the relationship between the atomic force microscope (AFM) nano-morphology and ageing of bitumen. The purpose of this paper is to find out the effect of thermal oxygen ageing on the nano-morphology of bitumen. Atomic force microscope (AFM) test sample of bitumen was prepared in this paper. Area ratio of bee-like structure, roughness, and maximum amplitude were selected as the nano-morphological parameters of the bitumen. The calculation method of nano-parameters was also proposed. Bitumen with different ageing degrees was prepared by thin film oven test (TFOT). Nano-morphological parameters of bitumen with different ageing degrees were obtained by AFM and analyzed with NanoScope Analysis, and the relationships between nano-morphological parameters and bitumen technical indexes after ageing, such as penetration, ductility, softening point, and viscosity were analyzed. The test results show that the wave crests and wave troughs of the bee-like structure on the surface of the bitumen alternate, while the other areas are relatively flat. The bee-like structure continues to develop as the ageing time prolongs, and the number of bee-like structures decreases, but the volume and the undulation degree increase. With the ageing time prolonging, the nano-parameters of bitumen, such as the area ratio of bee-like structure, roughness, and maximum amplitude, show a trend of increasing gradually, but the increasing rates become smaller and smaller. During the ageing process of bitumen, with the increase of nano-morphological parameters (area ratio of bee-like structure, roughness, and maximum amplitude), penetration at 25 °C and ductility at 15 °C of the bitumen decrease, and softening point and viscosity at 60 °C increase. AFM testing technology and image analysis method in this paper can be used for a reference in the nano-scale study of bitumen. [ABSTRACT FROM AUTHOR]

Two years ago, the Alberta government put in place a temporary oil-production quota. However, the quota's impact could well be felt in the province's oil production for years to come. The quota applied only to firms producing more than 10,000 barrels of oil per day and was instituted as a response to pipeline constraints that caused Alberta oil prices to be much lower than prices elsewhere. Production from both oilsands mines and oil wells dropped as soon as the government announced the quotas. The media warned that the quotas would force production to transfer to Saskatchewan, but the research for this paper found that this never occurred. The quota policy was announced in December 2018 and a week later, the price of Alberta oil had jumped from $29.09/bbl to $50.08 bbl, a 72 per cent rise. When the quota policy actually took effect the first of January 2019, the price increased again, but by much less. The anticipation of the quota alone was enough to create the desired price increase. The quota, which set limits for the total combined crude oil and bitumen permitted to be produced, was assigned to individual operators and designed to provide an 8.5 per cent reduction in oil production. The total quota was fixed at 3.56 million barrels a day in January 2019, but individual quotas could be traded across eligible operators, minimizing the overall costs of achieving the total goal. However, total production continued falling even when the quota was eventually relaxed; the market and a low world price created a scenario in which production fell below the amount permitted by the quota. All the oil companies reduced their production regardless of whether they fell within the quota's guidelines or not; however, the firms that were subject to the quota reduced their production more than the others. The quota was lifted in December 2020 when export capacity again became sufficient. While curtailing production had the desired result of raising Alberta oil prices and resolving the differential between local prices and the world benchmark, its ripple effects may well be felt in the longer term. This paper finds that fewer wells are being drilled and more wells are suspending production. Tradition dictates that when a well becomes inactive, it is rarely returned to a productive state. Those firms that resorted to low levels of drilling in order to meet the quota have created a situation that could affect Alberta oil production in the years ahead. [ABSTRACT FROM AUTHOR]

The oily fraction allows expansion and dissolution of the polymer particles within the bituminous matrix. This contribution studies the effects of adding a small quantity of a used engine oil (UEO) to bag waste plastic-modified 40/50 grade bitumen. The objective is to investigate the possibility of using the used oil as a plastic-bitumen compatibilizing agent. Penetration, softening point, Rolling Thin Film Oven Test (RTFOT), and Fourier transform infrared spectroscopy (FTIR) tests were used in this paper to characterize the waste plastic-modified bitumen (WPmB) and the used engine oil plastic-modified bitumen (UEOPmB). The Van Der Poal nomograph is used to complete the characterization of the studied binders. It was observed that adding used engine oil allowed incorporating greater plastic quantities into the pure bitumen. Moreover, both the WPmB and the UEOPmB have shown improved mechanical properties compared with pure bitumen. Obtained results demonstrated that oil addition enhances the aging resistance and reduces the low temperature cracking resistance of the UEOPmB. [ABSTRACT FROM AUTHOR]

This review paper shows several sections of bitumen, asphalt mixtures, polymers, and waste plastic in pavement engineering. The paper reviews and evaluates the influence of using waste polymer in improving the rheological and engineering properties of the modified binder and mixtures. Evaluation of properties and design of stone mastic asphalt mixtures are reviewed. Reports and studies had investigated the advantages and importance of using polymer in bitumen modification; however, they yet show a gap in research in terms of the role of waste polymer in improving the durability, aging, and fatigue life in the long term of service. [ABSTRACT FROM AUTHOR]

Copyright of Maintenance & Reliability / Eksploatacja i Niezawodność is the property of Polish Scientific & Technical Society Consumables, Polish Maintenance Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The interaction between bitumen colloidal and mineral aggregate is complicated owing to an intricate interplay of bitumen chemistry, aggregate mineralogy, and surface topography. Identifying the adsorption configuration of bitumen-aggregate interface has been a longstanding challenge in interface science and material engineering. In this paper, we report a mechanistic study using molecular dynamics simulation to uncover the adsorption configuration of bitumen-aggregate interface at the molecular scale and how aggregate mineralogy affects it. The results show that the adsorbed bitumen layer is densely distributed compared to bulk bitumen, and its structure is a superposition of two configurations: the layered configuration in the near-surface region arising from aggregation and parallel orientation of the bitumen molecules, and the gradient descent configuration in the region further away from the surface. The degree of concentration and radius of influence are significantly impacted by the mineral surface. Distributions of the individual bitumen fractions were also probed for the nearest bitumen layer to test the assumption of selective adsorption. The results suggest that the hypothese of selective adsorption is invalid for bitumen-aggregate interface systems investigated in this paper. The findings from the current study provide molecular insights into the topography of the adsorbed bitumen layer on the aggregate surface. [ABSTRACT FROM AUTHOR]

To investigate the effect of recycled engine oil bottoms (REOB) as a compatibilizer on the properties of styrene–butadiene–styrene-modified bitumen (SBS-PMB), this paper studied the preparation method, properties, and micro-mechanism of composite modification of matrix bitumen with SBS and REOB. Firstly, a multi-factor orthogonal experiment determined the optimal preparation scheme of REOB/SBS composite-modified bitumen (REOB/SBS-PMB). Then, the high-temperature stability rheological properties, and anti-aging performance of REOB-PMB were studied by testing Brookfield viscosity, elasticity recovery, and dynamic shear rheology (DSR) and by short-term aging simulation (TFOT). Finally, the microstructure, fraction content, and SBS particle dispersion of 70# matrix bitumen (70-MB), SBS-PMB, and REOB/SBS-PMB were compared and analyzed by tests of Fourier transform infrared spectroscopy (FTIR), rod-shaped thin-layer chromatography, and fluorescence microscopy to reveal the micro-mechanism of REOB improving SBS and bitumen compatibility. The research results showed that the mixing form of SBS and REOB in bitumen was mainly physical swelling and blending, with chemical changes also present that have a minor impact. The light fraction in REOB increased the flowability of bitumen, promoted the swelling of SBS, improved the compatibility between SBS and bitumen, and improved the high-temperature stability and rheological properties while reducing the impact of aging. [ABSTRACT FROM AUTHOR]

This paper aims at using a dilatant or shear thickening fluid (STF) [a non-Newtonian fluid consisting of particles of nano-silica suspended in a liquid medium, i.e., ethylene glycol (EG), which acts as a carrier fluid; proportion 40:60] as additive or modifier of bitumen in order to enhance its viscoelastic properties. A commonly-used performance grading (PG) system, storage stability test, and different conventional and rheological tests were carried out to optimize the dosage of the STF into the bitumen (investigating the influence of 2%, 4%, and 6% of STF on the bitumen) and to define the related properties. The results show that using 4% STF by weight of the binder (an asphalt binder with an 80/100 penetration grade) improves high-temperature viscoelastic properties and bitumen performance grading. [ABSTRACT FROM AUTHOR]

The strength growth of a bitumen emulsion-based cold in-place recycling asphalt mixture (BE-CIR) is time-dependent and time-consuming due to the addition of water. There is a great difference between the curing conditions of specification in the laboratory and the in situ conditions, which often leads to a great discrepancy between the results of lab specimens and the field cores. The main objective of this paper is to evaluate the curing effect on laboratory BE-CIR considering field-water evaporation and heat-transfer conditions. Four different curing methods were designed by using different combinations of waterproof layers, heat insulation layers, and variable temperature modes. The variations in temperature indexes, moisture content, air void, and indirect tensile strength (ITS) with curing time were tested, and the mutual influence of these indicators was analyzed. Furthermore, the results of the laboratory samples were compared with the field cores. Testing results show that the performance of the BE-CIR mixture is significantly different from that with no treatment, which is manifested as higher moisture content and lower air void and ITS under the same curing time. The internal temperature of the mixture is the main factor affecting the variation of moisture content, especially on the first curing day. The air void of the mixture has a strong linear relationship with the moisture content. Moisture content and ITS under different curing methods showed similar trends and could be divided into two stages. Taking the field cores as a benchmark, it can be concluded that the field-water evaporation condition should be considered in the setting of indoor curing methods, while the heat transfer could not. [ABSTRACT FROM AUTHOR]

Although archaeological excavations have recovered a large number of vessels used to hold perfumes or ointments in ancient Rome, little is known about the chemical composition or origin of the substances they contained. Most available information pertains to ointment and/or cosmetic bases rather than to essences. The discovery in 2019 of an ointment jar (unguentarium) made of rock crystal (quartz) that was sealed with a stopper and contained a solid mass in a Roman tomb in Carmona (Seville, Spain) was a rather unusual finding. This paper reports the results of an archaeometric study of the unguentarium stopper and its contents. Based on them, and on comparisons with commercially available patchouli and nard oil standards, the perfume held in the unguentarium was probably patchouli. To our knowledge, this may be the first time a perfume from Roman times has been identified, which is a major advance in this field. The unguentarium stopper consisted of dolomite, a material also unknown in this type of use, and bitumen was used to seal the unguentarium with the stopper. [ABSTRACT FROM AUTHOR]

With the aim to understand the effect of thermal condition on phase separation in polymer-modified bitumen (PMB), this paper numerically investigates four PMB binders under five thermal conditions between 140 and 180 °C. Based on a phase-field model previously developed by the authors for PMB phase separation, the updated model presented in this paper uses temperature-dependent parameters in order to approach the concerned temperature range, including mobility coefficients, interaction and dilution parameters. The model is implemented in a finite element software package and calibrated with the experimental observations of the four PMBs. The experimental results are well reproduced by the model, and it is thus believed that the calibrated parameters can represent the four PMBs. The simulation results indicate that the model proposed in this paper is capable of capturing the stability differences among the four PMBs and their distinct microstructures at different temperatures. Due to the transition of some PMBs from the thermodynamically stable state at 180 °C to the unstable state at 140 °C, a homogenization process may occur during the cooling applied numerically. After the transition, the PMBs start to separate into two phases and gradually form the binary structures controlled by the temperature. It is indicated that the cooling rate slightly affects the final pattern of the PMB binary microstructure, although the process can be more complicated in reality due to the potential dynamic reasons. [ABSTRACT FROM AUTHOR]

This manuscript provides an overview of the most commonly-produced bitumen roofing sheets, focusing on the types of reinforcements used for their production and the reinforcements' effects on the durability of tensile mechanical properties of roofing sheets under thermal loads. The paper includes the analysis of working conditions of roof coverings in the mid-European transitional climate, i.e., exposed to temperatures passing through 0 °C for three seasons in a year, periodic exposure to negative temperatures reaching −15 °C and positive temperatures up to +70 °C, justifying the above-mentioned emphasis on thermal load. It draws attention to technical problems related to the cooperation of roofing sheets with roofing substrates, with particular emphasis on concrete substrates. For the purposes of the work, the analyses were carried out with regard to the assessment of the service life of roof coverings made of various reinforcements working in conditions of variable temperatures and thus exposed to the transfer of thermal movements of substrate plates. The analyses also included the impact of different coefficients of thermal expansion of the materials in contact with other materials within roof coverings on the incidence of damage to cover layers. Particular attention was paid to the conditions resulting from the production process of roofing sheets effect on the durability of roof coverings made of these materials. Additionally, there were set directions for further work to calculate the impact of stresses, arising in layers of roof coverings during their operation in changeable negative and positive temperatures, on the incidence of mechanical damage to these coverings. [ABSTRACT FROM AUTHOR]

The study presented in this paper investigates the application of asphalt bitumen modification using a fast-reacting SBS polymer at a low modifier percentage. The hypothesis is that a fast-reacting styrene–butadiene–styrene (SBS) polymer that composes only 2% to 3% of the weight of the bitumen modification could extend the life of the pavement surfacing and pavement performance at relatively low input costs, increasing the net present value produced by the pavement during its life cycle. To confirm or refute this hypothesis, two types of road bitumens CA 35/50 and 50/70 were modified with low amounts of fast-reacting SBS polymer with the expectation of attaining properties similar to a 10/40–65 modified bitumen. For each type of unmodified bitumen, bitumen modification and comparative 10/40–65 modified bitumen, the following tests were conducted: needle penetration, softening point—ring and ball test method, and ductility test. The second part of the article focuses on a comparison of asphalt mixtures with different compositions of coarse-grain curves. For each mixture, complex modulus with varying temperatures and fatigue resistances are represented by the Wöhler diagram and compared. Based on in labo testing, the impact of the modification on pavement performance is evaluated. Life cycle changes for each type of modified and unmodified mixtures are quantified as road user costs, and attained benefits are compared with increased construction costs. [ABSTRACT FROM AUTHOR]

The objective of this paper is to assess whether existing pavement temperature prediction algorithms can be used to reliably determine Performance Grade (PG) design temperatures for Australian asphalt pavements. The results show good agreement between internationally and locally developed pavement temperature algorithms for the prediction of high pavement design temperature. There is more variability between models in the prediction of low pavement design temperature. The paper also provides a set of PG grading results for a range of Australian asphalt binders. The findings indicate that for a given design situation harder bitumen, ormore highly modified binder would be specified in Australia than in jurisdictions using the PG system. [ABSTRACT FROM AUTHOR]

In order to explore the diffusion and regeneration of bio-oil in aged bitumen, waste cooking oil (WCO), waste wood oil (WWO) and straw liquefied residue oil (SLRO) were selected in this paper. According to the surface wetting theory, the contact angle is obtained by combining laboratory experiments with molecular dynamics (MD) simulation, and the wetting parameters are calculated to evaluate the wetting behavior of bio-oil. The experimental phenomena of the wetting process and the main factors driving wetting are further analyzed. A permeation experiment is designed to obtain the permeation fusion layer (PFL). If the crossover modulus of PFLs changes compared with that of the aged bitumen, it is determined that the bio-oil penetrates the corresponding fusion layer. The results show that the motion of bio-oil included spreading and shrinking processes, and a precursor film played a pivotal role in the transportation of nanodroplets. Higher surface tension, lower viscosity and cohesion can effectively promote the wettability of bio-oil. A higher temperature and a longer permeation time are conducive to the permeation of bio-oil in aged bitumen. WCO with the strongest wettability has the weakest permeability, while WWO has superior permeability and can activate the macromolecules' surface activity, but its wettability is relatively weak. It is necessary to further modify WCO and WWO to be suitable rejuvenators. [ABSTRACT FROM AUTHOR]

This paper presents the results of an analysis of the changes in the stiffness of asphalt binders modified with a bio-flux additive and subjected to the processes of foaming and short-term ageing. The purpose of the analyses was to determine changes in the rheological properties of asphalt binder as a result of technological processes characteristic of hot and warm mix asphalt technology. Three asphalt binders with similar penetration but varying degrees of polymer modification were tested: 50/70, 45/80–55 polymer-modified bitumen, and 45/80–80 highly modified bitumen. Tests were carried out on four groups of binders: original binders, foamed binders after 14 days of storage, non-foamed binders after Rolling Thin Film Oven Test (RTFOT) ageing, and foamed binders after 14 days of storage subjected to RTFOT ageing. The master curves of the complex shear modulus G* were analysed, and three indexes of binder stiffening were determined, characterising the investigated effects. The tests showed that some of the stiffening indices significantly depended on the degree of polymer modification and the content of the bio-flux additive. Moreover, it was found that the foaming process in the case of paving-grade bitumen and polymer-modified bitumen did not contribute to the additional stiffening of the binders. [ABSTRACT FROM AUTHOR]

The present paper investigates the viscoelastic stress-strain responses of laboratory and plant produced warm mix asphalt mixtures containing basalt fiber dispersed reinforcement. The investigated processes and mixture components were evaluated for their efficacy in producing highly performing asphalt mixtures with decreased mixing and compaction temperatures. Surface course asphalt concrete (AC-S 11 mm) and high modulus asphalt concrete (HMAC 22 mm) conventionally and using a warm mix asphalt technique with foamed bitumen and a bio-derived fluxing additive. The warm mixtures included lowered production temperature (by 10 °C) and lowered compaction temperatures (by 15 °C and 30 °C). The complex stiffness moduli of the mixtures were assessed under cyclic loading tests at combinations of four temperatures and five loading frequencies. It was found that the warm produced mixtures were characterized by lower dynamic moduli than the reference mixtures in the whole spectrum of loading conditions, however, the mixtures compacted at the 30 °C lower temperature performed better than the mixtures compacted at 15 °C lower temperature, specifically when highest testing temperatures are considered. The differences in the performance of plant and laboratory produced mixtures were ascertained to be nonsignificant. It was concluded that the differences in stiffness of hot mix and warm mixtures can be attributed to the inherent properties of foamed bitumen mixtures and that these differences should shrink in time. [ABSTRACT FROM AUTHOR]

Bitumen binder is a component of asphalt mixtures that are commonly used as the materials constituting the upper layers of a pavement's structure. Its main role is to cover all the remaining constituents (aggregate, filler and other possible additives) and create a stable matrix, in which they are embedded due to the adhesion forces. The long-term performance of bitumen binder is crucial to the holistic behavior of the layer made of the asphalt mixture. In this study, we use the respective methodology to identify the parameters of the well-established Bodner–Partom material model. For the purposes of its parameters identification, we carry out a number of the uniaxial tensile tests with different strain rates. The whole process is enhanced with a digital image correlation (DIC) to capture the material response in a reliable way and to provide deeper insight into the experiment results. The obtained model parameters were used to compute numerically the material response using the Bodner–Partom model. Good agreement between the experimental and numerical results was observed. The maximum error for the elongation rates equal to 6 mm/min and 50 mm/min is of order of 10%. The novel aspects of this paper are as follows: the application of the Bodner–Partom model to the bitumen binder analysis and the DIC-enhancement of the laboratory experiment. [ABSTRACT FROM AUTHOR]

The increasing demand for water with the industrialisation of the world is becoming a major problem as there is a water shortage all over the earth. Therefore, the water problem is one of the important problems that need to be effectively solved. This paper presents the results of research on wastewater treatment of bitumen production in the Mangystau region, which after physical and chemical treatment methods is sent to natural evaporation fields. As a result of research work, a method of wastewater treatment of bitumen plant was developed, which includes two stages: distillation of water on the solar plant and ozonation in order to oxidize volatile organic matter. Distillation to obtain primary treated water of 70-75% volume was carried out at 33-37 ° ambient temperature and 15-30 kPa rarefaction, at the same time COD of water was reduced by 68%. [ABSTRACT FROM AUTHOR]

The use of solar energy to partially satisfy the demand for heat in the bitumen industry constitutes an enormous step towards industrial decarbonization. This paper investigates the effect of thermal fluctuations caused by solar energy usage in bitumen storage in the region of Rabat, Morocco. We studied different temperature ranges and storage periods, covering the most common scenarios in this region. This work inspected the impact of these studied conditions on the performance of 35/50 bitumen. After the simulation of fluctuations through thermal storage, we simulated short-term and long-term aging using RTFO and PAV tests, respectively. In addition to the needle penetration at 25 °C and the determination of softening point tests, we used a dynamic shear rheometer (DSR) and Fourier-transform infrared spectroscopy (FTIR) to assess the rheological and chemical evolutions of the samples. We found that thermal fluctuations enhanced the rheological performance of the binders by improving their rutting and fatigue cracking resistance. We observed that longer storage durations (three months) under thermal fluctuations made bitumen more prone to oxidation in the long term. We conclude that solar energy usage in bitumen storage is not detrimental as long as we avoid long storage periods (more than one month), especially when the maximum storage temperature is higher than 165 °C. [ABSTRACT FROM AUTHOR]

The paper is devoted to studying the influence of petroleum systems composition on the transformation of their resin-asphaltene substances in the process of thermal cracking. The research object included oil, natural bitumen, and their mixture at the ratio of 1:1. As a result of the study, the material balance of thermal cracking, the composition of the initial oil systems and thermolysis products were determined, and the molecular structure of resins and asphaltenes before and after the thermal treatment of oil systems was described. It has been found that bitumen cracking is accompanied by the formation of the largest amounts of gaseous (3.9%) and solid (2.3%) products, while oil cracking leads to the formation of significantly smaller amounts of gas (1.2%) and solid residue (0.1 %). The character of structural changes in resins during thermolysis is predominantly destructive due to dealkylation reactions and the destruction of cyclic systems. Asphaltene molecules are prone to condensation reactions with each other, as well as with resin molecules. Naphthenic cycles are also destroyed in asphaltenes, which leads to an increase in their aromaticity. [ABSTRACT FROM AUTHOR]

Nearly 70% of the global oil reserves are made up of unconventional oils such as heavy oils, bitumen, and tar sand. However, they are yet to be fully exploited as a result of the capital-, energy-, water-, wastewater-, and carbon-intensive nature of their development. To be in consistent with the current goals of climate crisis mitigations, technologies that are more environmentally friendly with high efficiencies are needed. This is where the toe-to-heel air injection (THAI) in situ combustion process comes in. However, experiments and semi-commercial operations have shown that THAI is a low-oil-production-rate process where there was nonlinear relationship between air injection rate and oil production rate. Therefore, to find out about the feasibility of adding an extra source of heat in order to improve oil production rates and with the second aim of testing the possibility of heating an annular catalyst layer surrounding the horizontal producer (HP) well such as in the in situ catalytic upgrading process (CAPRI™), a first-of-a-kind study of electrically-enhanced THAI (i.e. eTHAI) process is presented in this paper. The eTHAI involves surrounding the HP well with the electrical heating coils in which induced current flows so that heat is generated and released in the reservoir. Through reservoir numerical simulations using CMG STARS, it is found that it is indeed possible to electrically heat the HP well whilst conducting pre-ignition steam injection and subsequently operating in situ combustion. Regardless of the rate of heating, it is found that the shape and the stability of the combustion front are not affected by the incorporation of the electrical heating around the HP wellbore. In the eTHAI process, addition of extra heat from the electrical heating coils resulted in increased cumulative oil production to 32,000 m3 compared to 25,000 m3 in the base case model over the 834 days of process time. This is an increase in oil recovery by 28% over the same period compared to in the base case model. It is concluded that the resulting acceleration in oil production rates and recoveries implies earlier realisations of returns on investment. Moreover, it is found that the higher the rate of electrical heating, the wider the length of the HP well used for mobilised oil production (i.e. the wider the thickness of the mobile oil zone (MOZ)). It is also discovered that the higher the electrical heating rate, the less the air cooling effect and in turn the higher the quantity of heat that is distributed inside the reservoir. As a result, it is concluded that the increased distribution of higher quantity of heat by the heated air coming from the outlet zone of the VI wells of the eTHAI models results in increased oil mobilisation and production rates. However, future work should investigate the limiting electrical heating rate beyond which no appreciable increase in oil production rates is achievable. Finally, it is shown that electrically-enhanced THAI process operates stably, efficiently, and selective sectional heating of catalyst-surrounded wellbore is indeed feasible. [ABSTRACT FROM AUTHOR]