Bitumens physical properties

Modified Bitumen Membranes. These membranes were developed in Europe during the late 1950s and have been used in the United States since the late 1970s. There are two basic types of modified asphalts and two types of reinforcement used in the membranes. The two polymeric modifiers used are atactic polypropylene (APP) and styrene—butadiene—styrene (SBS). APP is a thermoplastic polymer, whereas SBS is an elastomer (see Elastomers, thermoplastic elastomers). These modified asphalts have very different physical properties that affect the reinforcements used. 

Styrene—butadiene—styrene modified bitumen is an elastomeric material mixed into an asphalt between 10 and 15%. By using high energy mixing, the SBS is uniformly dispersed throughout the asphalt to form a network, referred to as phase reversal because the minor component s (SBS) physical properties are displayed by the final mixture. A properly formulated SBS asphalt blend has an elongation of 100% or greater and is flexible down to temperatures below —6°C. 

The apparent deliberate selection and preparation of certain resources over others (birch bark tar over softwood products) is repeated throughout later European prehistory. Whilst we lack systematic comparative surveys of the physical properties of resin, heated wood and bark products, and bitumen, both choice and preference were being expressed. Yet, even if we had data of this nature, other factors are likely to have come into play. The ability to transform natural materials (such as wood or bark) into discrete organic substances then subject to myriad uses (hafting of tools and weapons just happens to be the most visibly persistent role) would have had a dramatic impact on those who made these substances. 

For many years, petroleum and heavy oil were very generally defined in terms of physical properties. For example, heavy oil was considered to be a crude oil that had gravity between 10 and 20° API. For example. Cold Lake heavy crude oil (Alberta, Canada) has an API gravity equal to 12°, but extra-heavy oil (such as tar sand bitumen), which requires recovery by nonconventional and nonenhanced methods, has an API gravity in the range 5 to 10°. Residua would vary depending on the temperature at which distillation was terminated, but vacuum residua were usually in the range 2 to 8° API. 

Recently, studies have been made to determine the properties of Utah bitumens (I, 2). Others (3-9) have studied the properties of Athabasca bitumens. The analyses of the bitumens have generally included physical properties, elemental analyses, distillation, and infrared... 

Figure 11.9 I llustration of the connection between hot water flotation efficiency and measured chemical and physical properties, including bitumen zeta potential From Schramm and Smith [250]. Copyright 1987, Canadian Society for Chemical Engineering.

Characterization of Feedstock and Catalysts. The elemental analysis and physical properties of various feedstocks used in this study are given in Table I. The data show that the virgin bitumen contains... 

To test these hypotheses, a tar sand bitumen containing 20 wt % pentane asphaltenes was characterized and processed by hydropyrolysis before and after removal of asphaltenes. Product yields and structure were determined and the influence of asphaltenes on results was determined by inferrence. Feedstocks and products were characterized according to elemental analysis, physical properties, simulated distillation, and carbon-type analysis. Inferences made in this study are discussed in the context of the reported literature. 

Feedstock Characteristics. The Sunnyside tar sand sample contains 9.3 wt % bitumen. The extracted bitumen was subjected to deasphaltening and results of three runs were 20.6, 19.9, and 21.4 wt % (20.6% average) of the total bitumen. The elemental analysis and physical properties of the bitumen,... 

Some physical properties and some distillation data for oils and bitumen are shown in Table II. Specific gravities and pour points are lower for light oils than for bitumen. Viscosities (ca. 6 cP at 77 F) for light oils are much less than the viscosity of the bitumen (ca. 3,000,000 cP at 77°F). Distillation data show that the light oils contain much more material boiling below the two cut points (275° and 425°C) than... 

Physical Properties and Distillation Data for Bitumen and Product Oils... 

This study of a test pavement using recycled HMA, in which the penetration of the old bitumen had been adjusted using new HMA, confirmed the durability of such a pavement and showed that it could maintain a comparatively good level of utility even after 15 years and 3 months of use. Also, with respect to the physical properties, we have found that the bitumen deterioration of layers of the HMA subject for public use was comparatively small and that the repeated reuse of pavement is indeed possible. Such a high evaluation of pavement recycling from the viewpoint of both utility and physical characteristics should broaden the possibilities for expansion into re-recycling. 

Physical Properties. Some properties of specific interest in the coating field are adhesion weatherability moisture permeation and absorption inertness to chemical environments color and service temperature range. Bitumens exhibit good adherence to almost any surface. Coatings with excellent weathering properties can be obtained by proper selection of the bitumen and formulation with other materials. 

The chemical and physical properties of clay suspensions produced during oil production from oil sands are described. With a composition of approximately 70 wt% water (with some unrecovered bitumen) and 30 wt%solids (>90% less than 44 gm in size)9 these clay suspensions consolidate very slowly. Clay aggregate or floe morphology has been shown to be a function of the water chemistry and can be manipulated to produce a tailings suspension that is easier to consolidate and dewater. Commercial oil sands processing has been going on in northeastern Alberta since 1967, and in that time approximately 250 million m3 of this difficult to dewater clay suspension has been produced. The reclamation options for this material (mature fine tailings) on a commercial scale are also outlined. 

C Guzman, G Montero, MI Briceno, ML Chirinos, I Layrisse. Physical properties and characterization of Venezuelan heavy and extra heavy crudes and bitumens. Fuel Sci Technol Int 7 571—598, 1989. 

Solvent extraction is very pertinent to the liquefaction of coal in the presence of a solvent and especially to the more recent concept of coprocessing coal with a variety of other feedstocks snch as heavy oils, tar sand bitumen, and residua (Chapters 18 and 19) (Speight, 2007,2008). There have been many attempts to define solvent behavior in terms of one or more physical properties of the solvent and not without some degree of success. However, it is essential to note that the properties of the coal also play an important role in defining behavior of a solvent, and it has been reported that the relative solvent powers of two solvents may be reversed from one coal type to another. 

The soap contains cationic surfactant as well as hydrochloric, or less usually, acetic or phosphoric acids. The acids are needed to convert amine-type emulsifiers to their protonated cationic forms but also to inhibit the ionization of acid groups in the bitumen. Cationic soaps typically contain 0.5-2.0% cationic surfactant, acid to pH 1 to 5, and optional additives such as water-soluble thickeners, electrolytes, latex, stabilizers and adhesion promoters which modify the physical properties or reactivity of the emulsion, or the properties of the bitumen film when cured. Some typical emulsion recipes are shown in Table 14.10. 

There have been a number of not particularly successful attempts to correlate asphalt physical properties to chemical properties, including SEC (10,19,35-40). Chollar et al. (41) attempted to relate a number of chemical and physical properties, including percentage LMS, with poor results. Huynh et al. (42) divided asphalt into a number of fractions by preparatory SEC and showed that the glass transition temperature (not precisely defined for asphalts), in moving from one fraction to the next, first decreased with increasing molecular size and then increased. Beazly et al. (43) used SEC and nuclear magnetic resonance (NMR) to estimate asphalt yields and viscosity from crude oil Woods et al. (44) used SEC fractions to study differences in maltenes from tar sand bitumens. 

Petroleum consists of four hydrocarbon-t3 es (saturates, aromatics, resins, and asphaltenes) that may be defined in terms of solubility, polarity, and MW. Of these structural t)q)es, asphaltenes have markedly adverse effects on the processability of petroleum and play a significant role in the physical properties of heavy oils and bitumen. Because of these effects, in this chapter, asphaltenes will be discussed in detail in terms of their properties, composition, and thermal chemistry during upgrading, as well as their influence on instability/incompatibility during the production, transportation and upgrading of petroleum. 

The effect of asphaltenes on the physical properties of heavy oils and bitumen has been studied extensively. It has been demonstrated that the viscosity of petroleum is significantly influenced by the presence and concentration of asphaltenes. Storm et al. demonstrated that when the relative viscosity of heavy oils was plotted versus asphaltenes concentration in both toluene (at room temperature) and vacuum residue (at 93°C), a straight line resulted. Thus, it was concluded that toluene is as good a solvent for asphaltenes as for vacuum resid. However, the amount of solvation is temperature dependent. By analyzing the temperature dependency of solvation. Storm et al. showed that the forces holding asphaltenes in the resid are very weak. Moreover, the fact that the solvation constant is the same for toluene at 25 °C as in a vacuum resid at 93°C implies that the forces between asphaltene colloidal particles and toluene are weaker. 

Petroleum is a complex mixture of hydrocarbons which is located in the Earth s crust in liquid, gaseous, and solid forms. Natural gas, heavy viscous oil and bitumens are forms of petroleum . This definition provided by a British encyclopedia is somewhat limited. Current scientific knowledge affords a more correct description of petroleum as a system containing numerous hydrocarbon components with different chemical natures. Such a correct definition allows a variety of physical properties and states related to internal structuring. 

Stockholm, or wood, tar as well as coal tar and bitumen, pitch or asphalt could be used alone or in admixture with other ingredients and fillers to give a range of sealants exhibiting differing physical properties. 

Cement-based waterproofing slurries are easy to use, non toxic, provide a fully bound and monoHthic surface without joints and can be easily applied on substrates with complex surface shapes. In contrast to other systems, cementitious waterproofing slurries can even be used on damp and wet mineral surfaces. Their physical properties are also less temperature dependent compared to bitumen based materials. 

However, to define conventional petroleum, heavy oil, and bitumen, the use of a single physical parameter such as API gravity or viscosity is not sufficient and is only a general indicator of the nature of the material. Other properties, such as the method of recovery, composition, and most of all, the properties of the bnlk deposit, must also be included in any definition of these materials. Only then will it be possible to classify petroleum and its derivatives (Speight, 1999). 

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