Base Case Process

Product Type 1 Raw Materials Handling 2 Conversion 3 4 5 Quality Control 6 Packaging 

Basic chemical products Feeding, pumping, compressing Chemical reaction Purification Separation Intrinsic quaiity Physical, thermal, chemical, rheological, properties Shipped tank cars, pipelines 

Finally, before leaving this topic, the reader should note that process creation and development of a base-case process are the subjects of Part One of this book, entitled Product and Process Invention— Heuristics and Analysis (Chapters 1-5.) 

Detailed Process Synthesis Using Algorithmic Methods 

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Figure 5.22 HDA process base case process data.

U.S. Department of Energy. Texaco gasifier IGCC base cases. Process Engineering Division Topical Report PED-IGCC-98-001, July 1998. 

In addition to attempting to provide heuristic roles for choosing Ihe base case, process synthesis research attempts also (0 develop systematic methods for the evolution of the flowsheet from the base case to the... 

Using the chemical engineering literature, complete the detailed database for the detailed design of the base-case process in Figure 3.19. When appropriate, indicate the kind of data needed from a pilot plant and how this data should be regressed. 

In which case, no base case process or other prior art exists. 

The Ethylene base case process is a front-end based technology, where the separation section is led by the de-ethanizer unit, and its oveihead product is fed to the acetylene hydrogenation imit. It has a capacity of 900,000 tons of high grade ethylene per annum. 

The information required to obtain a base-case process flow diagram is discussed and categorized into the six basic elements of the generic block flow process diagrana. The need to obtain reaction kinetics, thermodynamic data, and alternative separation methods is discussed in the context of building a base-case process. Special enphasis is placed on alternative distillation schemes and the sequencing of columns needed for such separations. 

Increase the utility feed rate by 50%, and maintain the base-case process feed stream... 

This reaction is normally carried out at tenperatures of 580 ° C- 660 ° C and at pressures of 35-70 bar [1,2]. With the development of new catalysts, operating pressures as low as 25 bar may be possible 31 and are assumed to be feasible in this analysis. In the base-case process provided, the reactor consists of a single-stage adiabatic packed bed of catalyst into which a small stream of recycle gas is fed for tenperature control. Over the range of conditions considered here, there are essentially no side reactions. 

A base case process is employed to demonstrate the tuning procedure of EPC using a second order plus dead time (SOPDT) transfer function of the form Process 1 [10]... 

The initial aim of the procedure is to generate a reasonable base case design that can be used for preliminary economic evaluation of the process. This can subsequently be optimized and/or compared with any process alternatives that are identified. The complete process is always considered at each decision level, but additional fine detail is added to the structure of the flowsheet at any stage. Established heuristics and equipment selection procedures are used together with new process synthesis insights to guide each flowsheet decision. 

To evaluate the economics of this process, a cost model has been developed to estimate the separation costs for a specific racemate [68, 69]. For this purpose, the sensitivity of the separation costs for several key process parameters have been established as compared to a base-case separation in which a purity of 99 % is required at an enantioselectivity of 1.15. The maximum solubility of the drug is set... 

Metal-catalyzed hydrophosphination has been explored with only a few metals and with a limited array of substrates. Although these reactions usually proceed more quickly and with improved selectivity than their uncatalyzed counterparts, their potential for organic synthesis has not yet been exploited fully because of some drawbacks to the known reactions. The selectivity of Pt-catalyzed reactions is not sufficiently high in many cases, and only activated substrates can be used. Lanthanide-catalyzed reactions have been reported only for intramolecular cases and also sulfer from the formation of by-products. Recent studies of the mechanisms of these reactions may lead to improved selectivity and rate profiles. Further work on asymmetric hydrophosphination can be expected, since it is unlikely that good stereocontrol can be obtained in radical or acid/base-catalyzed processes. 

Both these methods require equilibrium constants for the microscopic rate determining step, and a detailed mechanism for the reaction. The approaches can be illustrated by base and acid-catalyzed carbonyl hydration. For the base-catalyzed process, the most general mechanism is written as general base catalysis by hydroxide in the case of a relatively unreactive carbonyl compound, the proton transfer is probably complete at the transition state so that the reaction is in effect a simple addition of hydroxide. By MMT this is treated as a two-dimensional reaction proton transfer and C-0 bond formation, and requires two intrinsic barriers, for proton transfer and for C-0 bond formation. By NBT this is a three-dimensional reaction proton transfer, C-0 bond formation, and geometry change at carbon, and all three are taken as having no barrier. 

In this chapter, however, our objective is more restricted. We will purposely choose simple cases and make simplifying assumptions such that the results are PID controllers. We will see how the method helps us select controller gains based on process parameters (/. e., the process model). The method provides us with a more rational controller design than the empirical tuning relations. Since the result depends on the process model, this method is what we considered a model-based design. 

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