Plant Studies

After years of bench-scale and pilot-plant studies, constmction was begun on a gca 1600 m /d (10,000 bbl/d) unit in Sarawak, Malaysia, by Shell in a... 

E. B. Fred, I. L. Baldwin, and E. McCoy, Root Nodule Bacteria andEeguminous Plants, Studies in Science No. 5, University of Wisconsin Press, Madison, Wis., 1932. 

Pilot-plant studies have been conducted by Petrobras on many of the different oil shales from around the world. Tests indicate that many oil shales could be processed using the PETROSIX retorting technology (67) (Fig. 12). 

Boron is found in two underground ores, ulexite and colemanite. Research and pilot-plant studies have been completed to solution mine these ores, but as yet it is not done commercially. Boron is found in many different evaporite deposits (17). 

R. E. Horvath, Pioneer Plants Study User s Manual, Rept. R-2569/1-DOE, Rand Corp., SantaMonica, Calif., June 1983. 

For complex reac tions and with multistage CSTRs, more than three steady states can exist (as in Fig. 23-17c). Most of the work on multi-phcities and instabilities has been done only on paper. No plant studies and a very few laboratoiy studies are mentioned in the comprehensive reviews of Razon and Schmitz Chem. Eng. Sci., 42, 1,005-1,047 [1987]) and Morbidelli et al. (in Carberry and Varma, Chemical Reaction and Reactor Engineering, Dekker, 1987, pp. 973-1,054). 

Figure 14-12 illustrates the influence of system composition and degree of reaetant eonversion upon the numerical values of for the absorption of CO9 into sodium hydroxide solutions at constant conditions of temperature, pressure, and type of packing. An excellent experimental study of the influence of operating variables upon overall values is that of Field et al. (Pilot-Plant Studie.s of the Hot Carbonate Proce.s.s for Removing Carbon Dioxide and Hydrogen Sulfide, U.S. Bureau of Mines Bulletin 597, 1962). 

Figure 1.3.2 gives another perspective for scale-down to recycle reactor studies. In this actual case, after preliminary studies in a recycle reactor, a 5-stage adiabatic reactor was envisioned (Betty 1979.) Scaling down the proposed commercial reactor, a 3 diameter tube was designed with elaborate temperature compensation (heating and insulation) for pilot-plant studies (Betty 1968, 1969.) Small squares in the proposed reactor represent side views of cylindrical catalyst cutouts for the recycle reactor... 

Available in metal only, low pressure drop, low HETP, flooding limit probably higher than Raschig rings. Not much literature data available. Used mostly in small laboratory or semi-plant studies. 

The development of the Advanced Passive 6(K) MWe reactor began in 1985 with the EPRI Small Plant Study, and continued under DOE support to result in an NRC certifiable design by the end of 1994 (McIntyre,... 

The primary motivation of PSAs is to assess the risk of the plant to the public. The immediate purpose of the RSS was to support the Price-Anderson hearings on liability insurance (i.e., assess the financial exposure of a nuclear power reactor operator) a purpose which, even today, is beyond PSA technology. However, PSA is sufficiently precise to provide relative risk comparisons of reactor designs and sites. These uses of PSA were presented at the Indian Point hearings, and in defense of Shoreham. The PSAs for the high-population-zone plants (Limerick, Zion, and Indian Point) were prepared to show that specific features of these plants compensate for the higher population density relative to plants studied in the RSS. 

The practical implications of this experiment are that when evaluating the effects of shift work due to circadian effects, the type of task being carried out by the worker must be taken into account. For example, skill-based tasks would be expected to exhibit the performance changes characteristic of low memory load tasks, whereas performance variations in knowledge-based tasks would be expected to follow the pattern of high memory load tasks. Performance on rule-based tasks may depend on the degree of frequency of use of the rules, which in turn may determine the memory load. If these results were confirmed by further process plant studies, it would have implications for when different types of operation (involving different levels of memory load) should be scheduled to reduce circadian rhythm effects and minimize errors. 

In order to do a risk analysis properly, the analyst must understand human capabilities, including the capability to recover from errors. Human error data may be available from generic sources or from in-plant studies done previously. 

The bulk of the information in the report is included in a 317-page appendix that contains systems descriptions, station blackout fault trees, diesel generator historical data, and diesel generator common cause failure analysis results for 18 different nuclear power plants. Tables and graphs are well organized and present data correlated to each plant studied. The study also contains conclusions and recommendations for improving reliability. 

American Council for an Energy-Efficient Economy. (198fi). Residential Conservation Power Plant Study. Washington, DC ACEEE. 

Materials Hnadiing in LAP Plants. Phase li. Total Plant Study of Longhorn AAP (1974), AD-B001021L... 

Anon, Modernization of Materials Handling in LAP Plants. Phase II. Total Plant Study of Lone Star AAP , Final TR 2, Jan 23-Nov 74, Contract DAAA21-74-C-0210, Ind Tech Assoc Inc (1974) 26) Ibid,. . Total Plant Study... 

As mentioned in the introduction, various reviews over the last ten years show that many plants contain bioactive polysaccharides. Most of the plants studied were chosen due to their traditional use for different kinds of illnesses where the immune system could be involved. The following section will describe the pectic type polymers from the plants most studied for their structure, and activities related to the structure where possible. 

Perhaps the most interesting aspect of this set of studies is the question posed in the recent paper by Schmidt et al. (2004) and deals with the reality of the patterns they observed. Is the polymorphism observed a result of the calculation methods used in the study, neural network (NN), and multivariate statistical analysis (MVA) Would increased sampling result in a greater number of chemo-types It is entirely possible, of course, that the numbers obtained in this study are a true reflection of the biosynthetic capacities of the plants studied. The authors concluded—and this is a point made elsewhere in this review—that ... for a correct interpretation a good knowledge of the biosynthetic background of the components is needed. ... 

In addition to the bitter acids and essential oils, the flowers of hops offer a rich array of polyphenolic compounds, primarily chalcones and their accompanying flavanones, many of which are prenylated derivatives (Stevens et al., 1997,1999a, b). The most prominent flavonoid in all plants studied was xanthohumol [342] (3 -prenyl-6 -0-methylchalconaringenin chalconaringenin is 2, 4, 6, 4-tetrahydroxychalcone) (see Fig. 4.11 for structures 342-346). Several additional chalcones—variously adorned with 0-methyl and/or C-prenyl functions—were also encountered, along with their respective flavanones. Three new compounds were described in the Stevens et al. 

A pilot plant is built and operated in series or in parallel with studies of individual process steps if needed. There are several reasons for pilot-plant studies ... 

Tomato root growth bloassay of leaf extracts. Three hundred mg samples of fully expanded leaves were taken from each plant studied. Each sample was ground with a Polytron1 in 30 ml of distilled water and the extract was filtered. Five ml aliquots of each extract were pipetted onto three layers of germination paper in a 10 by 10 by 1.5 cm plastic petri dish. Distilled water was used as a control treatment. Twelve tomato seeds were placed in a 3x4 array in each dish, and incubated at 20C for 168 hours, prior to root measurement. The experimental design was a completely randomized design with five replications (dishes) per treatment except the control which had 10 replications. The experiment was repeated each week for 9 weeks. 

The reactor performance may be specified independently of the detailed design of the reactor. The conditions for the optimum, or near optimum, performance may be known from the operation of existing plant or from pilot plant studies. 

Collect together all the kinetic and thermodynamic data on the desired reaction and the side reactions. It is unlikely that much useful information will be gleaned from a literature search, as little is published in the open literature on commercially attractive processes. The kinetic data required for reactor design will normally be obtained from laboratory and pilot plant studies. Values will be needed for the rate of reaction over a range of operating conditions pressure, temperature, flow-rate and catalyst concentration. The design of experimental reactors and scale-up is discussed by Rase (1977). 

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