Flowsheets simplified

Figure 21.2 Combination of gravity-flotation beneficiation flowsheet (simplified), Wheal Jane...

Figure 4.2. Flowsheet simplified nitric acid process.

Where possible, introducing extraneous materials into the process should be avoided, and a material already present in the process should be used. Figure 4.6h illustrates use of the product as the heat carrier. This simplifies the recycle structure of the flowsheet and removes the need for one of the separators (see Fig. 4.66). Use of the product as a heat carrier is obviously restricted to situations where the product does not undergo secondary reactions to unwanted byproducts. Note that the unconverted feed which is recycled also acts as a heat carrier itself. Thus, rather than relying on recycled product to limit the temperature rise (or fall), simply opt for a low conversion, a high recycle of feed, and a resulting small temperature change. 

Figure 14.8a shows a simplified flowsheet for the manufacture of acetic anhydride as presented by Jeffries. Acetone feed is cracked in a furnace to ketene and the byproduct methane. The methane is used as furnace fuel. A second reactor forms acetic anhydride by the reaction between ketene from the first reaction and acetic acid. 

The preceding definitions of economic potential and total annual cost can be simplified if it is accepted that they will be used to compare the relative merits of difierent structural options in the flowsheet and difierent settings of the operating parameters. Thus items which will be common to the options being compared can be neglected. 

Ethyl chloride (C2H5CI) can be manufactured by catalytically reacting ethanol and hydrochloric acid (El-Halwagi et al., 1996). Figiu 7.7 is a simplified flowsheet of... 

Fi ire 8.7 Simplified flowsheet for viscose rayon production (from El-Halwagi and Srinivas, Synthesis of reactive mass-exchange networks, Chem. Eng. Set., 47(8), p. 2116, Copyright 1992, with kind permission from Elsevier Science Ltd., The Boulevard, Langford Lane, Kidlington 0X5 1GB, UK). 

Figure 8.8 A simplified flowsheet of the Kraft pulping process (Dunn and ETHalwagi, 1993).

In some cases, they may be anticipated by a knowledge of the status of the process data prior to the start of engineering acthity. The larger projects are somewhat easier to group than the smaller ones. Process engineering is not always handled as completely for the small jobs. This is to say that flowsheets may be simplified, detailed equipment and line schedules may not be required, and the over-all project can be completely visualized at the outset, which is not the case with large projects. 

Figure 2.33 (A) A simplified flowsheet of beach sand processing ...

The employment of charcoal adsorption in hydrometallurgical processes offers several advantages (i) the process flowsheet is simplified, since thickening, washing, and filtration steps are avoided this implies a reduction in the capital as well as the operating costs, and... 

Figure 28.3a shows a simplified flowsheet for the production of isopropyl alcohol by the direct hydration of propylene3. Different reactor technologies are available for the process and separation and recycle systems vary, but Figure 28.3a is representative. Propylene containing propane as an impurity is reacted with water according to the reaction ... 

Figure 3 A simplified flowsheet for the hydrometallurgical recovery of base metals using metal...

Figure 5 A simplified flowsheet and materials balance for the recovery of copper from oxidic and transition ores by heap leaching, solvent extraction and electrowinning.

Figure El5.1 shows a simplified flowsheet for the conversion of N2 and H2 to ammonia (NH3) when argon (A) is present in the feed. After the reaction of N2 and H2...

A simplified process flowsheet for Example 2.1 (from Madron, 1985). 

Let us introduce a simple example to illustrate the previous concepts. The simplified process flowsheet presented in Fig. 1 (Madron, 1985) consists of four units interconnected by eight streams. We are interested in the estimation of the total flowrates of the system. If these variables are measured for streams 1, 7, and 8, then the measurement matrix C is of dimension (Z x g), where Z = 3 and g = 8. 

Typical reaction conditions of the RCH/RP process37,38,336 are T=120°C P=50 bar / =1.01 P/Rh=50-100 aqueous/organic phase=6 concentration of rhodium 10-1000 ppm pH of the aqueous phase 4-10. The RhH(CO)(tppts)3 catalyst345 is prepared in situ from rhodium-2-ethylhexanoate, for example, by addition of tppts in water. The process engineering is enormously simplified in comparison to classical oxo plants. Figure 1 shows the flowsheet of the RCH/RP oxo process.38,424... 

Figure 2. Simplified flowsheet of 500-lb/hr pulverized-fuel-fired furnace...

Fig. 8. Simplified flowsheets of operations required in preparation of (ai dried fruit and Ibl dried vegetable products. Operations 111 and (2) are required only tor certain fruits, such as prunes. Operation (3) is required only for certain vegetables, such as potatoes. Operation (4 is required only for certain end products...

Fie I. Simplified flowsheet ol operations involved in preparing mall... 

A simplified flowsheet of cryogenic upgrading plant is given in Fig. 6. The plant, consisting of two identical trains, is capable of processing 260... 

Fig. 1. Simplified flowsheet of incineration main in a hazardous waste treatment complex. (After Tillman)...

Minor experimental modifications, such as the use of hydrophilic complex-ants to ease the scrubbing and stripping of the loaded solvents and simplify the flowsheets. 

The conceptual development of a typical chemical process remains somewhat of an art. Usually, experience with similar process plants leads to an initial process flowsheet. Parameter optimization on that flowsheet can be used to determine the best economic design. Other flowsheets can be generated by adding/removing unit operations and process streams and changing the structure of the process flowsheet. A simplified depiction of this synthesis process is shown in Fig. 5. 

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