Pilot plant data on processing

Cany out reactions (Rl) and (R4) consecutively over a Ag-gauze catalyst by reacting ethylene in a stream containing oxygen and carbon monoxide. To consider this as an alternative processing concept, laboratory or pilot-plant data on the rates of reaction are necessary. 

During process development, a model can be developed as soon as a conceptual flow sheet has been formulated. This model can be updated as more information about the process is obtained. Even at an early stage in the project, the model can be used to assess the preliminary economics of the process and the effect of technological changes on these economics. The model can aid in interpreting pilot-plant data and allows the study of many process alternatives. 

According to Bisio (62), scale-up can be achieved by maintaining the dimensionless groups characterizing the phenomena of interest constant from small scale to large scale. However, for complex phenomena, this may not be possible. Alternatively, dimensionless numbers can be weighted so that the untoward influence of unwieldy variables can be minimized. On the other hand, this camouflaging of variables could lead to an inadequate characterization of a process and a false interpretation of laboratory or pilot plant data. 

Conventional Fixed-Bed Hydroforming. Pilot plant results on Hastings, California, East Texas, West Texas, and mid-continent heavy naphthas for the fixed-bed process are summarized in Table V the feed stock inspections are presented as Table VI. Yield-octane curves based on these data are on Figure 2, where the wide variation from naphthas of different compositions is apparent. The following tabulation shows the relative yields at two octane levels ... 

In many cases, the preliminary feasibility survey indicates that additional research, laboratory, or pilot-plant data are necessary, and a program to obtain this information may be initiated. Process development on, a pilot-plant or semiworks scale is usually desirable in order to obtain accurate design data. 

We begin the analysis by collecting all the information that is known about the process from the technical Uterature - joiunals, books, and patents. Also we can obtain information from company brochvues on plant operations, pilot plant data, and laboratory data. Table 3.5.1 contains some of these data, operating conditions, and specifications. 

Both Bayer and InfraServ Knapsack carry out similar projects in their design departments. A project can include conceptual process design as well as basic and detail engineering. For the modeling, simulation, and optimization of chemical processes, several tools like CHEMCAD [592] or Aspen Plus [516] are used. In addition, laboratory experiments may be required to determine reaction parameters or other physicochemical data. A project can also include the planning, construction, operation, and analysis of a pilot plant. Depending on the customer s demands, not all of these project phases are executed. 

The MTG process is one of several processes based on ZSM-5 catalysts which are currently licensed by Mobil to the petroleum and petrochemical industry. Over 25 commercial plants have been commissioned using these catalysts. All of these applications use fixed-bed reactors and, very importantly, all were scaled-up from bench-scale pilot plant data (ref. 2). The major advantage of fixed-bed technology is that it can be relatively simple and requires minimum scale-up studies. This successful scale-up experience with ZSM-5 catalyst was an important consideration in the MTG process development for the New Zealand plant. 

A heavy-oil stream at 320 K is used in an absorber to remove dilute quantities of pollutant A from an airstream. The heavy oil is then recycled back to the process, where A is stripped. The process is being run on a pilot plan basis, and information for scale-up is desired. The current absorber is a 16-plate sieve-tray column. Pilot plant data are as follows ... 

As mentioned throughout the discussion of preliminary process synthesis and the creation of the process flow diagram, the process simulator usually plays an important role, even if a simulation model is not prepared for the entire flowsheet. When parts of a simulation model exist, it is common for the design team to assemble a more comprehensive model, one that enables the team to examine the effect of parametric changes on the entire process. In other cases, when the process simulators have not been used for design, a simulation model is often created for comparison with the pilot-plant data and for parametric studies. 

Your R D department has done substantial pilot plant work on this new process and has determined the following correlations to assist you in designing the HDS reactor. You also have processing data available from an older HDS unit within your company to use as a baseline. 

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