Bitumen content

This measurement provides a definition of the bitumen content in bitumen materials as the portion soluble in carbon disulfide (in France, in trichloroethylene, carbon tetrachloride or tetrachloroethylene). The method is defined by AFNOR NF T 66-012 or IP 47, or ASTM D 4 (the latter is not equivalent to the others). 

By far the most widespread use of NMR in an on-line production environment is the utilization of downhole exploration tools by petroleum service companies such as Schlumberger, Halliburton, and Baker Hughes. Articles on these unilateral NMR systems are found in the patent databases, " academic literature, and on-line resources provided by the exploration companies. The references provided here are just a few examples in a very prolific field. The technique is applied in high-temperature and pressure situations and currently is used down to a depth of about 10 km (6 miles) to produce a picture of water/oil content in the adjacent rock formations as well as to derive permeability, diffusivity, and hydrocarbon chemistry information. Mobile unilateral NMR systems such as the NMR-MOUSE are also being developed in order to take benchtop NMR systems into the field to perform analysis of geological core samples at the drill site. NMR analyzers are also being developed to determine the bitumen content and properties in tar sand production and processing. " " ... 

The final two techniques do not involve water as the separating media, and depend less on the surface chemistry considerations of the aqueous processes. The bitumen content of an oil sand is normally determined by extraction with an organic solvent, and a scale-up of this technique for commercial operation has been proposed. 

Statement 1. This is still an accurate description of the oil sand system. The clay is largely kaolinite and illite, with essentially no evidence of montmorillonite (2). The viscosity of the bitumen ranges from 5000 to about 75,000 cS at 100 °F, with the higher values being observed near the bottom of the deposit (2). As the bitumen content of an oil sand increases, its water and clay content decrease (7). 

Other factors indicated m the data of Tables 1 and 2 include Pour Point—defined as the lowest temperature at which the material will pour and a function of the composition of the oil in terms of waxiness and bitumen content Salt Content—which is not confined to sodium chloride, but usually is interpreted in terms of NaCl Salt is undesirable because of the tendency to obstruct fluid flow, to accumulate as an undesirable constituent of residual oils and asphalts, and a tendency of certain salt compounds to decompose when heated, causing corrosion of refining equipment Metals Content—heavy metals, such as vanadium, nickel, and iron, tend to accumulate in the heavier gas oil and residuum fractions where the metals may interfere with refining operations, particularly by poisoning catalysts. The heavy metals also contribute to the formation of deposits on heated surfaces in furnaces and boiler fireboxes, leading to permanent failure of equrpment, interference with heat-transfer efficiency, and increased maintenance. 

Post-impact sediments were penetrated by research well Nordlingen-1973 near the center of the basin and described in detail by Jankowski (8). They consist of a "basal unit" overlying the suevite, a 140 m thick laminite series, 60 m of marl and a clay layer at the top. Bituminous sediments mainly occur in the laminite series (Figure 1). In the Nordlingen-1973 well, in which the laminite series was recovered between 256 and 111m depth, Jankowski (8) distinguished four subunits a basal clinoptilolite subunit very rich in organic matter (256-244 m), an analcime subunit with low bitumen concentration (244-195 m), a bituminous subunit (195-145 m) and a diatomaceous subunit with lower bitumen content (145-111 m). Deposition of these sediments was estimated to have extended over a period of 0.3 to 2 Ma (8). 

Early analyses for 14 archaeological asphalts from various sources are collected in Table II. The late R. J. Forbes of the Shell Laboratories in Amsterdam contributed most, with samples from Ur and Babylon as well as from Mohenjo Daro in the Indus Valley far to the east (3). Analytical methods were not described clearly, yet several similarities in the results of diflEerent analysts are evident. The bitumen content of nine... 

Four asphalts from highland sites were atypically high in bitumen the two from Farukhabad mentioned above and two others from Djaffara-bad in Table VI. One of each pair had a bitumen content near 33%, only moderately higher than typical asphalts, but the other two had 48 and 61%, two or three times the typical percentages. They were probably raw or hardened seepages, an indication supported by the presence of vegetal matter. They provide direct evidence that at least some asphalts... 

All other sources in Table VIII are from Zagros locations, especially the foothills and valleys from Ain Gir to Bebehan from which multiple samples were obtained. The seepages of Ain Gir contained more bitumen and less sand than the dried and rock asphalts, which are much alike. Weathered and unweathered rock asphalts from Mordeh Pel were hardly distinguishable, as were the Bebehan samples in other respects than bitumen content. The samples from M-i-S, Mordeh Pel, and Rijab are probably too lean to have been used as source materials. But the similarities at Ain Gir and Mordeh Pel suggest that the bitumen in any seepages at other sites would have resembled that in the asphalts there. 

These results support the idea that re-recycling is possible if (1) a RAP mixing ratio of 50% is used, (2) the penetration of old bitumen is adjusted using only for new HMA, and (3) the bitumen content is set using a reiterative... 

Fig. 14 Relationship between bitumen content and dynamic stability...

L/t samples, respectively. These values are consistent with previous determinations of the bitumen content of Green River oil shales. (11)... 

The bitumen content of the tar sand of the U.S.A and Canada varies from zero to as much as 22% by weight. There are, however, noted relationships between the bitumen, water, fines, and mineral contents for the Canadian tar sands. Similar relationships may also exist for the U.S.A. tar sands, but an overall lack of study has prevented the uncovering of such data. 

For the Canadian tar sands, bitumen contents from 8% to 14% by weight may be considered as normal (or average). Bitumen contents above or below this range have been ascribed to factors that influence impregnation of the sand with the bitumen (or the bitumen precursor). There are also instances where bitumen contents in excess of 12% by weight have been ascribed to gravity settling. 

The lumenescic method is based on an investigation of the bitumen dispersion area. The bitumen content in a layer rises above the crude oil or gas deposits. Samples from the layer are selected from shallow depths, and investigated using ultra-violet light. 

The model accounts for the dramatic change in oil production rate which is observed. The fast initial rate is governed by the rate constant k (first order in kerogen content). The latter slow rate is governed by the sum of the two bitumen reactions, which are assumed first order in the intraparticle bitumen content and have rate constants k2 and kc At the temperatures of interest, k is much greater than k2 + kc so that the first step of the reaction goes virtually to completion before there is any appreciable conversion of the bitumen. 

Tar sands containing as low as 8 percent bitumen can be thermally processed without external energy input to get satisfactory yields of oil. Tar sand with even lower bitumen content can be processed with good oil yield if a portion of the gas or oil products or some cheaper external fuel, such as coal, can... 

Flexibility and Fatigue Resistance. The data presented in Figure 4 indicate that a given mix stability level may be attained using a variety of bitumen contents with the corresponding sulfur contents. For example, 1000-lb stability mixes may be made with asphalt contents of 2-10%. The major component influencing mix flexibility is the asphalt content. Thus, a lean mix composition, with only 2% asphalt, would be very brittle whereas the mix with 10% asphalt would be quite flexible and able to conform to roadway deformations without cracking. 

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