Selected unit process operations

Availability of material balances for selected unit process operations (Table 1.1)... 

Availability of Material Balances for Selected Unit Process Operations... 

At the heart of a leaching plant design at any level—conceptual, pre-liminaiy, firm engineering, or whatever—is unit-operations and process design of the extraction unit or hne. The major aspects that are particular for the leaching operation are the selection of process and operating conditions and the sizing of the extrac tion equipment. 

Understanding the chemistry of the process also provides the greatest opportunity in applying the principles of inherent safety at the chemical synthesis stage. Process chemistry greatly determines the potential impact of the processing facility on people and the environment. It also determines such important safety variables as inventory, ancillary unit operations, by-product disposal, etc. Creative design and selection of process chemistry can result in the use of inherently safer chemicals, a reduction in the inventories of hazardous chemicals and/or a minimization of waste treatment requirements. 

Step 1.4 Select the Subject Facility. It is important to decide on the focus of your audit during the preparation stage. You may wish to audit a complete process or you may want to concentrate on a selection of unit operations within a unit process. 

Process Flowsheet Batch vs. Continuous operation Detailed unit operations selection Control and operation philosophy Information above plus process engineering design principles and experience... 

The combination of several unit operations into a single piece of equipment can eliminate equipment and simplify a process. There may be inherent safety conflicts resulting from this strategy (see Section 2.4). Combining a number of process operations into a single device increases the complexity of that device, but it also reduces the number of vessels or other pieces of equipment required for the process. Careful evaluation of the options with respect to all hazards is necessary to select the inherently safer overall option. 

FCC feed characterization is one of the most important activities in monitoring cat cracking operation. Understanding feed properties and knowing their impact on unit performance are essential. Troubleshooting, catalyst selection, unit optimization, and subsequent process evaluation all depend on the feedstock. 

The main aims of MicroChemTec are the development of a unit construction kit for micro reactors, definition of standardized interfaces, investigations of modules on the market for their suitability for affiliation in the unit construction kit, documentation for this purpose, and demonstration of functioning of the concept with the example of selected unit operations or processes. 

DeFine [Di-olefine saturation] A process for converting di-olefins to mono-olefins by selective dehydrogenation. Developed by UOP for use with its Pacol process. First commercialized in 1986 and now incorporated in all new Pacol plants. Six units were operating in... 

Econamine A process for removing acid gases from natural gas by selective absorption in diglycolamine (also called [2-(2-aminoethoxy) ethanol], and DGA). Developed by the Fluor Corporation, the El Paso Natural Gas Company, and the Jefferson Chemical Company and widely used. Later versions, developed by Fluor Daniel International, include the Fluor Daniel Econamine and the Econamine FG processes. More than 30 units were operating in 1996. See also Aromex. 

The procedure consists of three steps. The first step is to identify all the desired product quality factors or attributes for the new product. Then what follows is the selection of the appropriate product form and microstructure, a stable surfactant system with the right performance based on phase behavior, and the appropriate active ingredients in order to realize those quality factors previously identified. Finally the process flowsheet will be created with the equipment units and process operating conditions determined. 

Some asceptic processes are developed initially in non-sterile facilities and need to be re-designed to produce a sterile product. Thus the type, size and material used for vessels, piping and tubing (particularly product contact surfaces), the selection of appropriate equipment for each unit process i.e. mixing, filtration, filling, etc., the use of disposable or re-usable equipment, the order of unit operations, the fluid transfer between unit operations and... 

Data transfers, in floating point engineering units or in status states, are requested by the expert system. Thus the distributed system does not transmit all measurements and alarms on a fixed scan basis, but rather the process data are accessed as required for inference. In a sense, the expert system is acting like an expert operator, who focuses attention or scans the process operation selectively, using expertise to determine specific areas of attention. 

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