Refinery processing, simplified

Isomerization. Isomerization of any of the butylene isomers to increase supply of another isomer is not practiced commercially. However, their isomerization has been studied extensively because formation and isomerization accompany many refinery processes maximization of 2-butene content maximizes octane number when isobutane is alkylated with butene streams using HF as catalyst and isomerization of high concentrations of 1-butene to 2-butene in mixtures with isobutylene could simplify subsequent separations (22). One plant (Phillips) is now being operated for this latter purpose (23,24). The general topic of isomerization has been covered in detail (25—27). Isomer distribution at thermodynamic equiUbrium in the range 300—1000 Kis summarized in Table 4 (25). 

Data Acquisition As part or the understanding, the measurements that can be taken must be understood. A useful procedure to prepare for this is to develop a tag sheet for the process (Lieberman, N.P., Troubleshooting Refinery Processes, PennWell Books, Tulsa, 1981, 360 pp). An example of a simplified sheet is given in Fig. 30-5. 

Figure 4.12 Products and simplified product streams of oil refinery processes. The yellow color indicates processes using zeolite catalysts.

Figure 1.1 Simplified refinery process flow diagram.1...

A simplified flow diagram of the refinery process is shown in Figure 13.17. The initial crude separation is accomplished by two stages of fractionation. An... 

Figure 9-8 shows the simplified P ID of the oil refinery process, while the CGU representation in UML can be shown in figure 9-9. Detailed model of the oil storage CGU (CGU-Cl) is shown in figure 9-10. Generic safety procedures are defined as associated with Tank, Pump, connection point, while more specified safety procedures are specified in the level of Pump-1-1, Tank-1-1, etc. 

These processes are discussed in more detail in the following subsections. A simplified flow diagram of the various refinery processes and products is provided in Fig. R-1. 

FIG. R-1 Simplified petroleum refinery process flow diagram. (Source Environment Canada.)... 

The methods employed neeessarily vary widely from one refinery to another, depending on the crude processed, the nature and location of the market, the type of equipment available, and many other factors. However, for simplifieation, it may be considered that all refining processes fall into one of four basic categories. 

Figure 9.1. Simplified processing scheme of an oil refinery. [Adapted from J.W. Gosselink, CatTech, 4 (1998) 127.]...

Sulphuric acid is the largest volume chemical in the world with an annual production of about 180 mill, t/year which is used primarily for phosphate fertilizers, petroleum alkylation, copper ore leaching and in smaller quantities for a number of other purposes (pulp and paper, other acids, aluminium, titanium dioxide, plastics, synthetic fibres, dyestuffs, sulphonation etc.). The major sulphur sources for sulphuric acid production are sulphur recovered from hydrocarbon processing in the refineries and from desulphurisation of natural gas, SO2 from metallurgical smelter operations, spent alkylation acid, and to a minor extent mined elemental sulphur and pyrites. A simplified flow sheet of a modem double-absorption plant for sulphuric acid production from sulphur is shown in Fig. 1. 

The first step in good pretreatment practice is the segregation of major wastewater streams. This frequently simplifies waste treating problems as well as reducing treatment facility costs. Treatment at the source is also helpful in recovering byproducts that otherwise would not be economically recovered from combined wastes downstream [35]. Four major pretreatment processes that are applicable to individual process effluents or groups of effluents within a refinery are sour water stripping, spent caustics treatment, ballast water separation, and slop oil recovery. These are discussed below. 

In this section, we use a simplified refinery model in order to demonstrate the concept of using mathematical programming for the planning of process-yield-based... 

Understanding refining chemistry not only allows an explanation of the means by which these products can be formed from crude oil but also offers the luxury of predictability. This is very necessary when the different types of crude oil accepted by refineries are considered. And the major processes by which these products are produced from crude oil constituents involves thermal decomposition. There have been many simplified efforts to represent refining chemistry (Figure 4-4) that, under certain circumstances, are adequate to the task. However, refining is much more complicated than such representations would indicate (Speight, 1999). 

Figure 5.28 Simplified flow schemes of (a) a conventional and (b) Mobil Oil s membrane solvent dewaxing processes. Refrigeration economizers are not shown. The first 3 million gallon/day commercial unit was installed at Mobil s Beaumont refinery in 1998. Polyimide membranes in spiral-wound modules were used [41-43]...

Figure 1.6 indicates where a lubricant base oil plant fits into the process flow scheme of a typical refinery - if ever there is such a thing. Although the scheme is simplified, the inter-relationship between the base oil plant and other process units and product streams is evident. In a sense, the base oil plant and the fuel-upgrading plant, such as the catalytic cracker, compete for feedstock from vacuum distillation. These interactions are very important to the logistics and production economics of producing base oils. 

Compared to SMDS, this simplified process employs a different catalyst in the synthesis stage and does not include a Heavy Paraffinic Conversion stage for producing the finished middle distillate fractions. The syncrude product is a broad boiling range of hydrocarbons (Table 4), and the relative amounts of individual products can be varied by adjusting the reaction conditions. Alternatively, syncrude products can be processed in existing refineries into finished transportation fuels. 

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