Laboratory pilot unit

Pfizer had been cooperating with the Bureau of Mines on the process since its scale-up to the Arizona pilot plant. The company decided to take a more active role in the investigation and development of the process when the copper smelter demonstration was completed in 1971. Working closely with the Bureau of Mines, Pfizer constructed a laboratory pilot unit in which the viability of the process was confirmed. This was followed by a two-phase laboratory program consisting of an exhaustive study of potentially competitive absorption systems and elucidation of the process chemistry. 

Specific reactor characteristics depend on the particular use of the reactor as a laboratory, pilot plant, or industrial unit. AH reactors have in common selected characteristics of four basic reactor types the weH-stirred batch reactor, the semibatch reactor, the continuous-flow stirred-tank reactor, and the tubular reactor (Fig. 1). A reactor may be represented by or modeled after one or a combination of these. SuitabHity of a model depends on the extent to which the impacts of the reactions, and thermal and transport processes, are predicted for conditions outside of the database used in developing the model (1-4). 

Economy of time and resources dictate using the smallest sized faciHty possible to assure that projected larger scale performance is within tolerable levels of risk and uncertainty. Minimum sizes of such laboratory and pilot units often are set by operabiHty factors not directly involving internal reactor features. These include feed and product transfer line diameters, inventory control in feed and product separation systems, and preheat and temperature maintenance requirements. Most of these extraneous factors favor large units. Large industrial plants can be operated with high service factors for years, whereas it is not unusual for pilot units to operate at sustained conditions for only days or even hours. 

The intrinsic rejection and maximum obtainable water flux of different membranes can be easily evaluated in a stirred batch system. A typical batch unit (42) is shown in Figure 5. A continuous system is needed for full-scale system design and to determine the effects of hydrodynamic variables and fouling in different module configurations. A typical laboratory/pilot-scale continuous unit using computer control and on-line data acquisition is shown in Figure 6. 

One can to outline a general approach for medium selection along with a test sequence applicable to a large group of filter media of the same type. There are three methods of filter media tests laboratory- or bench-scale pilot-unit, and plant tests. The laboratory-scale test is especially rapid and economical, but the results obtained are often not entirely reliable and should only be considered preliminary. Pilot-unit tests provide results that approach plant data. The most reliable results are often obtained from plant trials. 

The objeetive of seale-up in reaetor design is to determine a eri-terion or eriteria on whieh to base the transfer of the laboratory seale into a full-seale eommereial unit. Before proeeeding from a laboratory to an industrial seale, additional investigations are required. However, it is diffieult to define these additional steps to gather all the information as promptly as possibe and at minimum eost. The mediodology of proeess development leading to seale-up beeomes die prineipal faetor for die sueeess of die operation. In aehieving diis purpose, experiments are elassified into diree main types laboratory, pilot plant, and demonstration units. 

The mill has been developed, partly at the University of Toronto, Canada1-20 21) and commercialised by General Comminution Inc. in Toronto. Capacities range from 20 kg to 10 tonnes of dry material per hour. A small laboratory pilot mill has an inside diameter of 160 mm and fits on a bench. The large, 640 mm diameter unit has external dimensions of about 2mx2mxlmin terms of height, length and width. 

The increase in octane observed using dealuminated faujasite compared to high cell size rare earth exchanged faujasite has been correlated with the Si/AI ratio of the sieve and with the sodium content (3). While the relationship between Si/Al ratio as measured by unit cell is confirmed by pilot unit studies in our laboratory. Figure 1, the relationship with sodium content is more complicated. Figure 2. Sodium added to the catalyst after hydrothermal dealumination reduces activity but does not affect octane, while sodium present before hydrothermal dealumination increases activity but does reduce octane. This result implies that selectivity for octane is related to structures formed during... 

The test at M. W. Kellogg s and the test in the ARCO pilot nnit were done with different feeds, with different catalysts and in different pilot nnits, so it was not expected that the yields should be identical. The feed to the M. W. Kellogg s pilot unit was a synthetic Statfjord atmospheric residne and the catalyst used was a Filtrol 900 catalyst containing nickel and vanadinm contaminants [1]. This pilot unit was also pressurized. In the ARCO pilot unit at Chalmers the feed was a laboratory distilled Statfjord atmospheric residue and the catalyst was an almost metal-free EKZ eqnilibrinm catalyst from Katalistiks. The ARCO nnit is working at atmospheric pressnre. 

The operating conditions for the three processes are very similar— only temperatures are somewhat dissimilar. The Shell Development system, employing a modified Friedel-Crafts system, operates at a lower temperature—150°-210°F vs. 250°-400°F for the other two processes. However, the equilibrium effects of the temperature differences are minimized as shown by the similarity in n-C4 and n-C5 yields shown in Table VI. Unleaded octane numbers for C5/C6 isomerate, obtained from a pure C5/C6 straight-run fraction, could not be found in the literature for the Shell process. However, pilot unit operations charging laboratory blends of n-C5, n-C6, and C6 naphthenes have been reported (26, 45). In the Shell process the use of antimony trichloride and hydrogen has considerably reduced the amount of side reactions for a Friedel-Crafts system so that the yield for this process is quite close to the yield structure for the other two processes. 

After the (1 x) laboratory batch is determined to be both physically and chemically stable based on accelerated, elevated temperature testing (e.g., 1 month at 45°C or 3 months at 40°C or 40°C/80% RH), the next step in the scale-up process is the preparation of the (10 x) laboratory pilot batch. The (10 x) laboratory pilot batch represents the first replicated scale-up of the designated formula. The size of the laboratory pilot batch is usually 30-100 kg, 30-100 liters, or 30,000 to 100,000 units. 

This chapter concerns the most important reactive separation processes reactive absorption, reactive distillation, and reactive extraction. These operations combining the separation and reaction steps inside a single column are advantageous as compared to traditional unit operations. The three considered processes are similar and at the same time very different. Therefore, their common modeling basis is discussed and their peculiarities are illustrated with a number of industrially relevant case studies. The theoretical description is supported by the results of laboratory-, pilot-, and industrial-scale experimental investigations. Both steady-state and dynamic issues are treated in addition, the design of column internals is addressed. 

The simple prototype unit discussed here is capable of continuously monitoring a process stream with rapid response to surface tension changes, and accuracy within 1-2%. Initial investigations indicate that a commercial unit based on this design would be capable of data acquisition, alarm monitoring, and/or closed-loop control of a process variable in a laboratory, pilot plant or production scale installation. A commercial instrument based on the work done in this laboratory is being developed and marketed. 

A number of different types of laboratory scale units have been developed to simulate commercial catalytic crackers. These include fixed bed (MAT), fluidized bed, and riser units.(1,2,3) In particular, for simulating commercial riser FCC units which process residue, a riser pilot plant is the preferred choice. 

Total (15) reports that operation of their pilot plant is not satisfactory for feedstocks with a viscosity greater than 80 cSt at 100 C. They state that thermal shock simulation and feedstock atomizing and evaporation are unsatisfactory in their laboratory scale unit. 

Mobile units for photocatalytic treatment have been constructed (126,127). The European Joint Research Center laboratory pilot plant, placed on a truck, includes Ti02 loaded on membranes in UV-irradiated tubular reactors behind microfiltration and ultrafiltration modules. The waste water flow rate for this unit was typically 40 L hr-1, and hydrogen peroxide was added to the photocatalytic process (134). 

Building supercritical fluid extraction units for an ever growing number of new products it was realized that for laboratory and pilot units only one standard equipment programme was no longer sufficient. 

The required heat of reaction is supplied by external heating of the reaction vessel, or, for laboratory-scale or pilot units, by electrical heating. Full-scale plant is either directly fired, or heated by circulating reacting liquids through an external pipe still. Some... 

A raw gas concentration of between 10-2000 mgW was selected so as the tests in the laboratory adsorption unit and pilot plant could be conducted in an acceptable time span. Flow velocity during adsorption was 0.1-0.5 m/s while relative humidity was set at between 20% and 70%. Each of the measurements was performed at room temperature (20°C to 25°C). The number of ACC layers used in the tests varied between 2 and 10 layers, depending on the parameter to be measured. Table 1 contains specific data on the plant as well as the test conditions. 

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