Pilot-plant design objectives

The system is illustrated in Figure 1. Inputs are a data base including pilot, commercial, and literature sources. The type and extent of data are compatible with plant design objectives. Although the contribution of all data sources is significant, the role of a pilot test facility is central to the development of sound technology. 

The students then are required to go into a development laboratory for actual experimentation work to get them acquainted with materials, materials handling, and translation of laboratory procedure into equipment, and to learn how to take exact plant data. They will also learn that there are a number of points that can be best obtained later through pilot plant operation therefore, one objective of the development laboratory can be a pilot plant design. 

The other common objective for calculating the number of countercurrent theoretical stages (or mass-transfer units) is to evaluate the performance of hquid-liquid extraction test equipment in a pilot plant or to evaluate production equipment in an industrial plant. Most liq-uid-hquid extraction equipment in common use can oe designed to achieve the equivalent of 1 to 8 theoretical countercurrent stages, with some designed to achieve 10 to 12 stages. 

For this last stage, the one-at-a-time procedure may be a very poor choice. At Union Carbide, use of the one-at-a-time method increased the yield in one plant from 80 to 83% in 3 years. When one of the techniques, to be discussed later, was used in just 15 runs the yield was increased to 94%. To see why this might happen, consider a plug flow reactor where the only variables that can be manipulated are temperature and pressure. A possible response surface for this reactor is given in Figure 14-1. The response is the yield, which is also the objective function. It is plotted as a function of the two independent variables, temperature and pressure. The designer does not know the response surface. Often all he knows is the yield at point A. He wants to determine the optimum yield. The only way he usually has to obtain more information is to pick some combinations of temperature and pressure and then have a laboratory or pilot plant experimentally determine the yields at those conditions. 

The objective of scale-up in reactor design is to determine a criterion or criteria on which to base the transfer of the laboratory scale into a full-scale commercial unit. Before proceeding from a laboratory to an industrial scale, additional investigations are required. However, it is difficult to define these additional steps to gather all the information as promptly as possibe and at minimum cost. The methodology of process development leading to scale-up becomes the principal factor for the success of the operation. In achieving this purpose, experiments are classified into three main types laboratory, pilot plant, and demonstration units. 

The operations of the 250 T/D pilot plant are designed to demonstrate the operability of the EDS liquefaction section and obtain the scaleup data required for design of a commercial facility. Key objectives are demonstration of unit operability,... 

The solvent-refined coal (SRC) processes were originally developed to produce cleaner boiler fuels from coal. A 0.5t/day plant was built in 1965 and scaled up in 1974 into two separate pilot plants located at Wilsonville (SRC-I, 6t/day) and Fort Lewis, WA (SRC-I, 50t/day). The Fort Lewis plant was later converted to an SRC-II unit. Due to the more severe conditions required for SRC-II, the capacity was downgraded to about 25 t/day. The objective of the SRC-II process was to produce distillate products. Detailed designs for large-scale plant were subsequently prepared, although these plants were not built. The Wilsonville plant continued to be funded... 

Objective Receive briefings from the Assembled Chemical Weapons Alternatives (ACWA) staff and contractor representatives concerning plans for the Blue Grass Chemical Agent Destruction Pilot Plant (BGCAPP) design and secondary wastes discuss and arrive at initial approach to task meet with public stakeholders expand report outline and identify further information needed. 

Objective Receive briefings and attend selected sessions of in-process review meeting of the ACWA staff and contractor representatives concerning plans for the Pueblo Chemical Agent Dcstraction Pilot Plant (PCAPP) design and secondary wastes meet with public stakeholders review initial drafts of report chapters and discuss additional information to be sought. 

Pilot Plant Operation. The pilot plant operation was the second phase of the research program and was designed to deliver the data necessary to plan, build, and operate a commercial size demonstration plant. In order to accomplish these objectives, a pilot plant of sufficient capacity was constructed and operated for an extended period of time. 

The goal of this work was to establish a method that allowed the selection of batch size and agitation speed during scale-up, with the objective of reproducing the selectivity of the system as measured by the amount of ethanol formed. It is important to remember that in the pharmaceutical industry, scale-up often occurs using existing multipurpose equipment. In some cases, when economical factors allow, specialized pilot-plant equipment is designed. 

If possible, control strategy tests can also be conducted in the pilot plant, with the results tied into simulations and models. Time and cost constraints, however, typically limit how much design uncertainty can actually be effectively eliminated as a new process is being developed. Further, some unit operations cannot be reliably modeled or scaled up. In addition to the objectives listed above, another objective of the control system is to allow some compensation for uncertainties in the scale up of the new process design (Ref. 5). 

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