Petroleum preparation

Several attempts have been made to investigate anaerobic pathways for desulfurization. Mixed cultures of sulfate-reducing bacteria were used to desulfurize model compounds, thiophenes [12], organosulfides [12,13], and petroleum preparations [14-16], Production of hydrogen sulfide and biphenyl from DBT has been demonstrated in other studies [17-22],... 

These requirements and other reasons make the preparation of petroleum before processing very necessary. Petroleum preparation includes drying (removal of water or dewatering) and desalting of petroleum, and complete or partial removal of dissolved gas. 

The extraction and preparation of petroleum and gas, which begin at the opening of the oil wells and end at the preparation units, follow a uniform technological system. There are many technological schemes of petroleum preparation. However, they are usually considered together with the petroleum extraction systems at the oil wells. 

This pressure extraction system is completely hermetically sealed. Therefore it excludes loss of gas and light petroleum fractions. The pressure extraction system allows for petroleum preparation at a central processing station for oils from several oil wells located in an area up to a 100-km radius. However, long distances for petroleum transport can lead to the creation of stable emulsions. With high humidity of the petroleum, this can lead to an increase in operations and transport costs. Nevertheless, it is one of the promising systems of petroleum extraction that is widely applied. 

There are many technological schemes for petroleum preparation. However, technical and economic considerations determine which scheme is used and the location of installation. It is known that the lowest capital investment and operational costs for petroleum preparation are for installations in locations of the greatest petroleum concentration (collector stations, commodity parks, and head offices). 

The optimal technological scheme for petroleum preparation is obtained with a scheme that allows petroleum to be processed to the allowable contents of water and salts, and with the necessary depth of stabilization at the lowest costs, in the shortest possible process time. 

In the modern petroleum industry, complex petroleum preparation is carried out in areas close to the oil wells. Therefore, complex installations for petroleum preparation at the petroleum wells also integrate the processes of drying, desalting and stabilization. 

Figure 5.2 shows the basic technological scheme of the installation for the thermal chemical petroleum preparation. 

Fig. 5.2 Technological scheme of the complex for thermal chemical petroleum preparation...

The petroleum prepared at the oil well comes to the petroleum refinery and the first process at modern refineries (excluding the refineries working only with non-conventional feed) is atmospheric rectification. The first refinery, which was opened in 1861, produced only kerosene and this was possible by using simple atmospheric distillation alone. The by-products of this refinery included tar and naphtha. For the next thirty years, kerosene still remained the main product that consumers wanted. Two significant events changed this situation ... 

On the risk management and risk governance for petroleum preparations in the Barents Sea Area , Risk Analysis, 32 (9) 1561-1575. 

Secondary butyl alcohol, methylethyl car-binol, 2-butanol, CH3CH2CH(Me)OH. B.p. I00°C. Manufactured from the butane-butene fraction of the gas from the cracking of petroleum. Used to prepare butanone. 

The choice between X-ray fluorescence and the two other methods will be guided by the concentration levels and by the duration of the analytical procedure X-ray fluorescence is usually less sensitive than atomic absorption, but, at least for petroleum products, it requires less preparation after obtaining the calibration curve. Table 2.4 shows the detectable limits and accuracies of the three methods given above for the most commonly analyzed metals in petroleum products. For atomic absorption and plasma, the figures are given for analysis in an organic medium without mineralization. 

The national organizations are often relayed into each profession by a body created and financed by this profession and which undertakes all or part of the work in preparing the standards. In the petroleum industry, this role is carried out in France by the BNPet (Bureau de Normalisation du Petrole) and in Germany by the FAM (Fachausschuss Mineralol-und Brennstoffnormung), in the United Kingdom by the IP (Institute of Petroleum), and in the USA by the ASTM (American Society for Testing and Materials). In the first two cases, the standards are published only by the national organizations (AFNOR and DIN respectively), while the IP and the ASTM also publish their own documents, only some of which are adopted by the BSI and ANSI, respectively. 

To prepare a sample of the hydrochloride, add 0-5 ml. of the base to 10 ml, of dilute hydrochloric acid in an evaporating basin and evaporate to dryness, preferably in a vacuum desiccator. Recrystallise the dry residue from petroleum (b.p. 60-80°). The hydrochloride separates as white crystals, m.p. 90°. 

The hydrochloride of the amine may be prepared precisely as that of the primary amine. For recrystallisation, boil a suspension of the powdered salt in petroleum (b.p. 60-80°), and then add acetone slowly in small drops until the boiling suspension just becomes clear allow the stirred solution to cool until crystallisation starts, and then chill in ice-water before collecting the colourless plates of the hydrochloride, which after drying in a vacuum desiccator have m.p. 132-134°. 

Dinitrobenzoylation. To 0 5 g. of powdered 3,5-dinitro benzoyl chloride (preparation, p. 240) in a dry test-tube, add 2 ml. of dry methanol and warm the mixture until a clear solution is obtained. Cool and filter off the solid ester which separates. Recrystallise from petroleum (b.p. 60-80 ), and take the m.p. (M.ps., pp. 536, 537.)... 

The acid chloride is available commercially, but it is more economical to prepare it from the acid as and when required. Furthermore, 3 5-dini-trobenzoyl chloride tends to undergo hydrolysis if kept for long periods, particularly if the stock bottle is frequently opened. The substance may, however, be stored under light petroleum. 

The melting points of these esters are usually much lower than those of the corresponding 3 5 dinitrobenzoates their preparation, therefore, offers no advantages over the latter except for alcohols of high molecular weight and for polyhydroxy compounds. The reagent is, however, cheaper than 3 5 dinitrobenzoyl chloride it hydrolyses in the air so that it should either be stored under light petroleum or be prepared from the acid, when required, by the thionyl chloride or phosphorus pentachloride method. 

About 200 ml. of light petroleum is required for recrystallisation. It is therefore advisable, for the sake of economy when the preparation is conducted by a large class of students, that onl about I g. of the crude material be recrystallised from this solvent. The crude compound may be employed in the preparation of p-amino-azobonzene. 

To prepare pure anhydrous o-benzoylbenzoic acid, dissolve the air-dried (or the moist) product in about 175 ml. of benzene contained in a 500 ml. round-bottomed flask fitted with a reflux condenser and heat on a water bath. Transfer the benzene solution to a separatory funnel, run oflF any water present, and dry with anhydrous magnesium sulphate. Concentrate the benzene solution to about 75 ml. and add light petroleum, (b.p. 60-80°) to the hot solution until a slight turbidity is produced. Allow to cool spontaneously to room temperature, then cool in ice to about 5°, collect the crystals and dry. The yield of pure, anhydrous o-benzoylbenzoic acid, m.p. 128°, is 32 g. 

Ethylbenzene. Prepare a suspension of phenyl-sodium from 23 g. of sodium wire, 200 ml. of light petroleum (b.p. 40-60°) and 56 3 g. (50 9 ml.) of chlorobenzene as described above for p-Toluic acid. Add 43 -5 g. (30 ml.) of ethyl bromide during 30-45 minutes at 30° and stir the mixture for a further hour. Add water slowly to decompose the excess of sodium and work up the product as detailed for n-Butylbenzene. The yield of ethylbenzene, b.p. 135-136°, is 23 g. 

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