Industrial Flowsheet

Characteristics of batch fluid bed spray granulators to produce tablet granulations in the pharmaceutical industry. Flowsheet given in Fig. 7.9. 

Figure 2 shows an existing industrial flowsheet for the manufacture of the product and figure 3 shows the optimal flowsheet as generated by the synthesis software. The basic structure of the two flowsheets is the same but Jacaranda suggested the cell concentration step uses microfiltration instead of a centrifuge which is certainly a feasible option. Results for an intracellular product also produced similar flowsheets to those used in practice (Steffens et al 2000a). 

Fig 2. Industrial Flowsheet for the purification of BST (dotted area shows final... 

Again most of the best solutions were very similar to the industrial flowsheets which include rotary drum filtration, solvent extraction, crystallization, filtration and drying. However when LCA or CWTM environmental criteria are used the solvent extraction process is replaced by cross flow filtration and ion exchange with other potential small changes. This is an expensive option but has clear environmental advantages. The... 

Kraft pulping is a common process in the paper industry. Figure 8.4 shows a simplifled flowsheet of the process. In this process, wood chips are reacted (cooked) with white liquor in a digester. White liquor (which contains primarily NaOH, NaiS, Na2C03 and water) is employed to dissolve lignin from the wood chips. The cooked pulp and liquor are passed to a blow tank where the pulp is separated from the spent liquor weak black liquor which is fed to a recovery system for... 

Rossiter and Douglas (1986) state that the first step in process design is to generate a basic structure for the flowsheet i.e. the choice of unit operations and interconnections which can be analysed, refined and costed, and then compared to alternatives. Thus, the generation of an industrial crystallization flowsheet gives rise to a number of optimization problems for which a systematic hierarchical decision process for particulate systems was proposed ... 

The electrostatic separation method is the exclusive choice in some specific situations, for example in the cases of rutile and ilmenite deposits. These deposits generally contain minerals of similar specific gravities and similar surface properties so that processes such as flotation are unsuitable for concentration. The major application of electrostatic separation is in the processing of beach sands and alluvial deposits containing titanium minerals. Almost all the beach sand plants in the world use electrostatic separation to separate rutile and ilmenite from zircon and monazite. In this context the flowsheet given later (see Figure 2.35 A) may be referred to. Electrostatic separation is also used with regard to a number of other minerals. Some reported commercial separations include those of cassiterite from scheelite, wolframite from quartz, cassiterite from columbite, feldspar from quartz and mica, and diamond from heavy associated minerals. Electrostatic separation is also used in industrial waste recovery. 

Commercial-scale application of solvents coming under the category of neutral reagents is largely found as applied to the nuclear industry materials, as in example, for the separation and refining of uranium, plutonium, thorium, zirconium, and niobium. A process flowsheet for extracting niobium and tantalum from various resources is shown in Figure 5.23. It will... 

A monthly publication of the Gulf Publishing Company. Another excellent publication that devotes itself to the process and project engineering of refineries and petrochemical operations. It has a flowsheet in every issue its yearly handbook issue gives over 100 processes flowsheets, and its NG, LNG, SNG Handbook issue gives more. It also has very good product studies and an excellent thermodynamics data series. Three times a year it lists all new worldwide construction in the petroleum and petrochemical industry. 

Problem description Figure 2.10 is the flowsheet for the industrial case study used to illustrate the application of the SSN based approach. Figure 2.11 is the corresponding SSN. 

The second mathematical formulation presented, is a design model based on the PIS operational philosophy. This formulation is an MINLP model due to the capital cost objective function. The model is applied to a literature example and an improved design is achieved when compared to the flowsheet. The design model is then applied to an industrial case study from the phenols production facility to determine its effectiveness. The data for the case study are subject to a secrecy agreement and as such the names and details of the case study are altered. 

Another widely used safety analysis method in process industry is the Hazard and Operability Analysis, better known as Hazop (Kletz, 1992). The conventional Hazop is developed to identify probable process disturbances when complete process and instrumentation diagrams are available. Therefore it is not very applicable to conceptual process design. Kletz has also mentioned a Hazop of a flowsheet, which can be used in preliminary process design, but it is not widely used. More usable method in preliminary process design is PIIS (Edwards and Lawrence, 1993), which has been developed to select safe process routes. 

Typical Processing Steps. The range of treatment processes is also quite variable. A generalized flowsheet of the unit operations that represents the state-of-the-art in the treatment of industrial wastewater from the petroleum/petrochemical industry is shown in Figure 9 (29,32). The unit operations included in this system are as follows ... 

The second part deals with applications of solvent extraction in industry, and begins with a general chapter (Chapter 7) that involves both equipment, flowsheet development, economic factors, and environmental aspects. Chapter 8 is concerned with fundamental engineering concepts for multistage extraction. Chapter 9 describes contactor design. It is followed by the industrial extraction of organic and biochemical compounds for purification and pharmaceutical uses (Chapter 10), recovery of metals for industrial production (Chapter 11), applications in the nuclear fuel cycle (Chapter 12), and recycling or waste treatment (Chapter 14). Analytical applications are briefly summarized in Chapter 13. The last chapters, Chapters 15 and 16, describe some newer developments in which the principle of solvent extraction has or may come into use, and theoretical developments. 

Figure 21 Composite flowsheet of waste treatment in soap and detergent industry (from Ref. 13).

The chemical processing techniques considered for synfuels flowsheet for the removal and recovery of sulfur are similar to those employed in other industries - notably natural gas sweetening, petroleum hydrodesulfurization, and coke oven gas treatment -but with certain significant differences attributable to the operating conditions encountered in synfuels processing. 

In principle, the flowsheet of an industrial facility is similar to those of the different hydrotreating processes (Figure 5.2-42) [61]. The feedstock C4 cut rid of water is pressurized to about 15 to 20 bar by pumping, injected with a hydrogen-rich gas and then, preheated by heat exchange with the reaction effluent and by steam. In a downflow stream, it then enters the reactor, which operates in a gas-liquid mixed phase with one or more catalyst beds (palladium, rhodium on inert alumina). After cooling, the isomerization products are flashed... 

TBP is a sufficiently powerful extractant for actinides that it may be used in diluted form. Dilution improves the hydrodynamic properties of the solvent, allowing more complete and rapid phase disengagement. Typically concentrations of 20-30 v/o TBP in OK are used in process flowsheets. Although TBP is relatively stable as an extractant, radiolysis does lead to the formation of some acidic phosphate esters, HDBP and H2MBP, which can impair process performance.289 An aqueous alkali wash of the recycled solvent is usually carried out to remove those by products. Radiolytic degradation of the diluent in the presence of nitric acid can result in the formation of hydroxamic acids,290 which can lead to fission product retention by the organic phase. Again the solvent wash is used to prevent the accumulation of such species. A comprehensive account of the industrial utilization of TBP has recently been published.291... 

Jenkins, J.A., Mills, A.L., Thompson, P.J., Jubin, R.T. 1993. Performance of centrifugal contactors on uranium and plutonium active PUREX flowsheets. In Solvent Extraction in the Process Industries ISEC 93, York, UK, September 16-21. Logsdail, D.H., Slater, M.J. Eds. Elsevier Applied Science, London and New York. 

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