Petroleum asphalt base

In pipelining, the trend is towards all-welded steel for long lines, and since the wall thickness is less than that of cast iron, protection is the more important. Many types of coating are used, from thick concrete to thin paint films, and each has its own particular suitability, but the majority of pipelines throughout the world today are coated with hot-applied coal tar or petroleum asphalt-base-filled pipeline enamels, into which reinforcing wraps, such as glass fibre are applied. 

A widely used classification of petroleum distinguishes between crude oils either on a paraffin base or on an asphalt base and arose because paraffin wax separates from some crude oils on cooling, whereas other oils show no separation of paraffin wax on cooling. The terms paraffin base and asphalt base were introduced and have remained in common use (van Nes and van Westen, 1951). 

The production of carbon fibres is based on the pyrolysis of organic fibres or precursors. The main starting materials are polyacrylonitrile (PAN) and pitch (coal tar or petroleum asphalt). They can be classified according to their mechanical performances ... 

Uses/Sources. Asphalt fumes arise from asphalt used for road construction, roofing, and coating of construction materials and in association with the production of asphalt from petroleum in asphalt-based paints... 

Petroleum crude oils, which are divided for the purposes of conventional classification into three main types—asphalt (or naphthenic)-base, paraffin-base, and mixed-base—contain varying amounts of hydrocarbons which readily solidify and are identified as wax. The asphalt-base crudes may contain only a trace of wax, while the wax content of the paraffin-base crudes and the mixed-base crudes may be as high as 15% or higher (73). Crude oils with a wax content as high as 35% are known. 

Naphthene oils are heavier and higher in viscous, volatile lubricating oils. Naphthene oils have an asphalt base since distillation produces solid and semi-solid asphalt residues. Lower densities and residues of petroleum or paraffin wax are a characteristic of paraffin oils. 

The chemical classification of petroleum that distinguishes between oils of a paraffin base from those of an asphaltene base was introduced into petroleum chemistry to distinguish the oils that separate paraffin on cooling from those that separate asphaltenes. The presence of paraffins is usually reflected in the paraffinic nature of the constituent fractions whereas a high asphaltic content corresponds with the naphthenic properties of the fractions. This could lead to the misconception that paraffin-base petroleum consists mainly of paraffins and that asphalt-base petroleum consists mainly of cyclic (or naphthenic) hydrocarbons. In order to avoid confusion, a mixed base has been introduced for those oils that leave a mixture of asphaltic petroleum and paraffins as residue from nondestruc-... 

The first step in the manufacture of asphalt-based coatings consists of the distillation of crude petroleum, which results in distillate fractions (gasoline, naptha, kerosene, diesel fuel, and gas oil). The fraction of crude oil that boils above approximately 300 C is not distilled, but is withdrawn from the bottom of the distillation... 

Asphaltic bitumens n. May be either naturally occurring materials or otherwise obtained from the distillation of asphaltic base petroleum they are readily soluble in aliphatic and aromatic hydrocarbons and have good film-forming properties. Usmani AM (1997) Asphalt science and technology. Marcel Dekker, New York. 

Over the years, multilayers of tar-based waterproofers replaced the hot asphalt used in roofing. In early 1900, asphalt became available from petroleum refining, and it was followed by oxidized bitumen interlaid with roofing felt and then alternated with a mineral base sheet, l" Asphalt-based materials are used extensively as binders, sealants, and waterproof coatings in diverse applications because of their low cost, inherent cohesive nature, weather-resistant properties, and ease of processing in the molten state. 

Several Pseudomonas spp. have been documented in the literature as common contaminants and derivatives of petroleum fluids (aromatic and paraffinic hydrocarbons, kerosene fuels, cutting oil emulsions), as well as, asphalt and asphalt-based coatings. Generally, their presence produces an alteration of fuel quality which leads to slime formation and subsequent blockages of filters and injection systems. In addition, several types of corrosion processes have been demonstrated which primarily involve pitting (Genner and Hill, 1981). Occasionally, the presence of marcescens has been reported in association with... 

Although distillation and elemental analysis of the fractions provide a good evaluation of the qualities of a crude oil, they are nevertheless insufficient. Indeed, the numerous uses of petroleum demand a detailed molecular analysis. This is true for all distillation fractions, certain crude oils being valued essentially for their light fractions used in motor fuels, others because they make quality lubricating oils and still others because they make excellent base stocks for paving asphalt. 

In this chapter, we will discuss petroleum products used for energy purposes, that is, motor fuels and heating fuels. Chapter 6 will be devoted to other products such as special gasolines, lubricants, petrochemical bases, and asphalts. 

The major portion of sait is found in residues as these streams serve as the bases for fuels, or as feeds for asphalt and petroleum coke production, the presence of salt in these products causes fouling of burners, the alteration of asphalt emulsions, and the deterioration of coke quality. Furthermore, calcium and magnesium chlorides begin to hydrolyze at 120°C. This hydrolysis occurs rapidly as the temperature increases (Figure 8.1) according to the reaction i. ... 

The market for tar-based road binders has declined considerably for a variety of reasons. Less cmde tar is available and the profits from the sales of electrode pitch and wood-preservation creosote or creosote as carbon-black feedstock are higher than those from road tar. In most industrial countries, road constmction in more recent years has been concentrated on high speed motorways. Concrete, petroleum bitumen, or lake asphalt are used in the constmction of these motorways. In the United Kingdom, for example, the use of tar products in road making and maintenance had fallen from 330,000 t in 1960 to 100,000 t in 1975 and is less than 100 t in 1994, mainly based on low temperature pitch which is not suitable for electrode or briquetting binders, but which is perfectly satisfactory as the basis for road binders. 

Pyrogels used by the US armed forces include (1) PT1, which is a complex mixt based on a paste of Mg and an oxidizer, bound with petroleum distillate and asphalt. Isobutyl methacrylate is used as a thickener. (2) PT2, which contains 5% isobutyl methacrylate as a thickener, together with Ba nitrate and a small quantity of asphalt. (3) PTV, which is described as an improved oil and metal incendiary mixt composed of 5% poly butadiene, 6% Na nitrate, 28% Mg, and a trace of p-aminophenol in 60% gasoline (Ref 5)... 

The classic definition of asphaltenes is based on the solution properties of petroleum residua in various solvents. The word asphaltene was coined in France by J.B. Boussingault in 1837. Boussingault described the constituents of some bitumens (asphalts) found at that time in eastern France and in Peru. He named the alcohol insoluble, essence of turpentine soluble solid obtained from the distillation residue "asphaltene", since it resembled the original asphalt. 

Three broad classes of crude petroleum exist the paraffin types, the asphaltic types, and the mixed-base types. The paraffin types are composed of molecules in which the number of hydrogen atoms is always two more than twice the number of carbon atoms. The characteristic molecules in the asphaltic types are naphthenes, composed of twice as many hydrogen atoms as carbon atoms. In the mixed-base group are both paraffin hydrocarbons and naphthenes. 

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