Hydrocarbonization flowsheet

Figure 3.24 shows the process flowsheet for an ethylene/ethylbenzene plant, Gas oil is cracked with steam in a pyrolysis furnace to form ethylene, low BTU gases, hexane, heptane, and heavier hydrocarbons. The ethylene is then reacted with benzene to form ethylbenzene (Stanley and El-Halwagi, 1995). Two wastewater streams are formed R ... 

Draw carefully a flowsheet for the recovery of isoprene from a mixture of C5 hydrocarbons by extractive distillation with aqueous acetonitrile according to the following description. 

The solvent comprised of 0.5 M DMDOHEMA and 0.3 M HDEHP in total petroleum hydrocarbon (TPH) diluent was used for separation of Am and Cm from lanthanides and fission products. A proposed technological flowsheet (PALADIN process) was tested in 2000.56 The flowsheet of this process is given in Figure 6.2. 

Hydrocarbon Processing excellent flowsheets, thermodynamic data series, and major articles. 

Figure 6.14 provides an example of the type of decision that a process designer would face in flowsheet evaluation. In this simple example, absorption with a regenera-ble solvent is used to capture (and recycle or sell) toluene and ethyl acetate, which might otherwise be emitted into the atmosphere. To increase the fraction of the hydrocarbons that are absorbed, the circulation rate of the... 

Another advantage is that a prereformer may be preferred in flowsheets for processing heavier feedstocks. The prereformer converts heavier hydrocarbons to methane before they are fed to the steam reformer. This allows the steam reformer to be designed for methane service. The prereforming catalysts are very sensitive to poisons. Therefore a good feed purification section is essential.70... 

The 10 lb/hr bench-scale hydrocarbonization facility at ORNL is shown in Figure 1 the equipment flowsheet is presented in Figure 2. With this apparatus, yield data have been generated for the mild hydrocarbonization of Wyodak subbituminous coal. Table I summarizes the proximate and ultimate analyses of this coal. When Wyodak coal is hydrocarbonized at 1040°F under a hydrogen pressure of 300 psi (315 psia total pressure), the yields obtained (expressed as wt % of MAF coal fed) were as follows oil, 20 gas, 21 water, 13 and char, 46. Figure 3 shows the variation of oil yield with temperature at a hydrogen pressure of 300 psi as observed, a gentle maximum occurs at about 1040°F. The steady-state, make gas composition under these conditions is presented in Table II. 

Extractive Distillation Recovery of Isoprene. A typical flow-sketch and material balance of distillation and solvent recovery towers for extracting isoprene from a mixture of cracked products with aqueous acetonitrile appears in Figure 13.25. A description of the flowsheet of a complete plant is given in Example 2.9. In spite of the fact that several trays for washing by reflux are provided, some volatilization of solvent still occurs so that the complete plant also has water wash columns on both hydrocarbon product streams. A further complication is that acetonitrile and water form an azeotrope containing about 69 mol % solvent. Excess water enters the process in the form of a solution to control poly-... 

FIGURE 18.1 Flowsheet for the main steps involved in chemical desalting. (From Hydrocarbon Processing [8] with permission.)... 

Typically the selectivity is above 99%. The following impurities may be found higher alcohols, hydrocarbons and waxes, esters, di-methyl-ether, ketones. With these elements we may proceed with the flowsheet description. 

Fig. 7.20 presents the final flowsheet. Firstly, the landfill gas enters an equilibrium adsorption unit, where the trace impurities HjS, aromatics and halo-hydrocarbons are removed. The next step is the separation of COj by physical or chemical absorption. 

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