Process Flexibility

The foregoing comparison of different valve arrangements for both full main air blower trains and TPG trains emphasizes its importance. The range of desired regenerator control, expected modes of operation, and system constraints all influence the choice of valve aiTangements. The selected arrangement depends on safety consciousness, cost considerations, and desired process flexibility. 

The processing flexibility of plastic-cellulose networks gives rise to products in various thickness, from a material only a few millimeters thick to structural panels up to several centimeters thick, that include [14] ... 

Electropolishing techniques utilise anodic potentials and currents to aid dissolution and passivation and thus to promote the polishing process in solutions akin to those used in chemical polishing. The solutions have the same basic constitution with three mechanistic requirements—oxidant (A), contaminater (B) and diffusion layer promoter (C) —but, by using anodic currents, less concentrated acid solutions can be used and an additional variable for process flexibility and control is available. 

In most industrial control applications, a process has already been almost completely defined and a tailored control system is built around that process. Our application is different. Because we wish to develop a consistent control approach for many, varied processes, flexibility is exceptionally important to us. 

Typical properties (Table 1.2) of these micro reactors preserved the basic characteristics of the existing processes, reduced the reactor volume with even slightly increased output and distinctively reduced residence time, thereby having a very large specific output [50]. In addition, the quality of the final product was improved, a high process flexibility was achieved, less raw material and catalyst were needed, specific expenses were reduced, and gains in economy of the process were achieved. Fewer staff members were needed for process operation. 

There is a real opportunity to reduce biodiesel production costs and environmental impact by applying modem catalyst technology, which will allow increased process flexibility to incorporate the use of low-cost high-FFA feedstock, and reduce water and energy requirement. Solid catalysts such as synthetic polymeric catalysts, zeolites and superacids like sulfated zirconia and niobic acid have the strong potential to replace liquid acids, eliminating separation, corrosion and environmental problems. Lotero et al. recently published a review that elaborates the importance of solid acids for biodiesel production. ... 

Pistikopoulos, E. N. and I. E. Grossmann. Optimal Retrofit Design for Improving Process Flexibility in Nonlinear Systems—I. Fixed Degree of Flexibility. Comput Chem Eng 13 1003-1016 (1989). 

Short residence time, minimal downstream separation, energy efficient, zero waste, low inventory, improved intrinsic safety, improved process flexibility, reduced area required, rapid product grade change, rapid response to market needs, improved control. 

Tm = 115 °C, lower than HDPE and LLDPE Specifc gravity = 0.91-0.94, lower than HDPE Easily processed Flexible without plasticizers... 

The use of mathematical programming models on an enterprise-wide scale to address strategic decisions considering various process integration alternatives yields substantial benefits. These benefits not only materialize in terms of economic considerations, but also in terms of process flexibility and improvements in the understanding of the process interactions and systems limitations. 

Norton, L.C. and Grossmann, I.E. (1994) Strategic planning model for complete process flexibility. Industrial el Engineering Chemistry Research, 33, 69. 

Properties. Shell s two-step SMDS technology allows for process flexibility and varied product slates. The liquid product obtained consists of naphtha, kerosene, and gas oil in ratios from 15 25 60 to 25 50 25, depending on process conditions. Of particular note are the high quality gas oil and kerosene. Table 2 gives SMDS product qualities for these fractions. 

Both air and oxygen processes can be designed to be comparable in the following areas product quality, process flexibility for operation at reduced rates, and on-stream reliability (97,182). For both processes, an on-stream value of 8000 h/yr is typical (196). The reliability of the oxygen-based system is closely linked to the reliability of the air-separation plant, and in the air process, operation of the multistage air compressor and power recovery from the vent gas is crucial (97). 

Reactions of organics are very rapid and occur in less than a second, thereby allowing a continuous flow-through system with good process flexibility at full scale when flows vary with time. The absorption dosage of radiation as a function of the penetration depth is shown in Figure 12.4. Clearly, the penetration depth increases with the applied voltage of electrons. Because an electron is able to penetrate as deep as 1 cm, a continuous flow reactor can be used. 

Jordan WC, Graves SC (1995) Principles on the Benefits of Manufacturing Process Flexibility. Management Science 41 577-594 Jung H (2004) Allgemeine Betriebswirtschaftslehre, 9th edn. R. Oldenburg, Munchen, Wien... 

A bunker reactor provides extra process flexibility if it is used upstream from the desulfurization reactor, especially with reference to the processing of... 

Mild chemical treatments are used to soften the wood chips and increase the amount of whole fibers. Some of the wood cell components are solubilized and the lignin is made more hydrophilic. The penalty paid for chemical addition is a reduction in yield, to levels of 80 to 90%. The benefits of chemical addition pulps are the increased ability to utilize hardwoods, lower energy requirements, stronger pulps, and increased process flexibility. Some of these pulps have been found to be suitable for products that generally require full chemical pulps. 

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