Pilot development unit scale

Controlled Fed-Batch Fermentations of Dilute-Acid Hydrolysate in Pilot Development Unit Scale... 

Index Entries Pilot development unit scale dilute-acid hydrolysate fed-batch fermentation feed rate carbon dioxide evolution rate. 

In the present work, the objective was to develop and implement a control algorithm for addition of hydrolysate, based on the total gas flow from a pilot development unit (PDU)-scale reactor. The control algorithm was tested in fed-batch fermentations of dilute-acid hydrolysate made with two different yeast strains. 

Research effort at Albany International Research Co. has developed unit processes necessary for pilot scale production of several species of reverse osmosis hollow fiber composite membranes. These processes include spin-dope preparation, a proprietary apparatus for dry-jet wet-spinning of microporous polysul-fone hollow fibers, coating of these fibers with a variety of permselective materials, bundle winding using multifilament yarns and module assembly. Modules of the membrane identified as Quantro II are in field trial against brackish and seawater feeds. Brackish water rejections of 94+% at a flux of 5-7 gfd at 400 psi have been measured. Seawater rejections of 99+% at 1-2 gfd at 1000 psi have been measured. Membrane use requires sealing of some portion of the fiber bundle for installation in a pressure shell. Much effort has been devoted to identification of potting materials which exhibit satisfactory adhesion to the fiber while... 

The pilot-production phase may be carried out either as a shared responsibility between the development laboratories and its appropriate manufacturing counterpart or as a process demonstration by a separate, designated pilot-plant or process-development function. The two organization piloting options are presented separately in Figure 1. The creation of a separate pilot-plant or process-development unit has been favored in recent years because it is ideally suited to carry out process scale-up and/or validation assignments in a timely manner. On the other hand, the joint pilot-operation option provides direct communication between the development laboratory and pharmaceutical production. 

In the EDS process development, bench scale research, operation of small pilot units, and engineering design and technology studies are being integrated with operation of a 250 T/D pilot plant and a 70 T/D FLEXICOKING prototype unit. ( Service Mark)... 

Integrated Testing. Although the individual steps of the process have been demonstrated in laboratory experiments, testing of the entire system is necessary in order to proceed along the path to commercialization. The integrated testing is currently planned to be comprised of three sequential steps, i.e., the laboratory model, the process development unit (PDU), and the "pilot-scale" unit. 

New pilot and commercial-scale equipment has been developed to blend and apply the composites and to determine total system costs (Figure 3). Several commercial-sized units based on the pilot design are now under construction. Each has a 500-gal capacity. They are fitted with a hot-oil heating system, heavy-duty mixers, and heated hoses that can deliver up to 200 lb/min of sulfur composite. They are designed to operate typically at 250°-300°F and at spray pressures of 20-100 psi. Each is self-contained except for electrical power which is provided by a stationary source or a portable generator. 

Of the various planar membrane designs that have appeared in the patent literature, development of the design from the Air Products consortium appears to have advanced the most. They have scaled up membranes from the laboratory scale to fuU commercial size as shown in Fig. 8.5 [21]. The membrane area has been scaled up by a factor of over 300 from the laboratory scale to the commercial scale membrane. Pilot scale membranes have been operated in a process development unit at pressures up to 425 psig (3 MPa) and temperatures up to 900 °C at commercial fluxes. Although other organizations have reported designs of planar membranes, there have been no reports from these organizations on the fabrication of planar membranes nor on the operation of planar membranes under commercially relevant conditions. 

Approaches used to develop gas-liquid mass dansfer correlations in bubble columns have been ported over to airlift bioreactors, and, unfortunately, they have brought some issues along with them. Airlift bioreactor correlations are highly empirical, and a unifying development method does not exist. Some correlations attempt to be very specific and use multiple inputs, which are hard to quantify in an industrial setting, or use inputs that are not independent of each other. The suggestion is similar as with the bubble column experimental units can use these more complicated correlations, but pilot or indusdial scale units will have to depend on empirical and design specific correlations. 

In this paper, we focused on the relevance of the commercial software HYSYS for the simulation of catalytic distillation columns. As in the current version of HYSYS the built-in RD module is not directly suitable for the simulation of the heterogeneous catalytic distillation process, this study is concentrated to develop a model for heterogeneous RD and to implement it in the HYSYS simulation environment. The objectives of this work are to develop a suitable simulation module for heterogeneous reactive distillation compatible with HYSYS and to apply it to an intermediary scale pilot plant unit. 

Early in the development of a new process, a productivity loss was encountered when the process was moved from the exploratory scale reactor to a larger pilot unit scale reactor. After study of many factors, the problem was resolved by installing a second impeller on the pilot reactor mixing shaft. While the action produced the desired results, it was not apparent why the one impeller system had performed below expectations. The traditional scale-up criterion of horsepower/unit voluaie for mixed vessels had been used when moving from the exploratory to pilot reactor. Historically this criteria had proved to be satisfactory. 

By control of pressure, a range of selectivities and dissolving powers can be obtained with a given solvent at given temperature. As pointed out by Stahl et aL in 1984 [25], commercial-scale fractionation operations based on this effect are possible future developments. Pilot plant units already exist [1]. 

Dry dense medium (pneumatic fluidized-bed) separation has been used, but has not received wide attention by the industry. An area of promise for future development is the use of magnetically stabilized dense medium beds by using ferro or magnetic fluids (2,10). Laboratory and pilot-scale units such as Magstream are available. In this unit, material is fed into a rotating column of water-based magnetic fluid. Particles experience centtifugal forces and... 

The need for a pilot plant is a measure of the degree of uncertainty in developing a process from the research stage to a hiU commercial plant. A modification to a weU-known process may go directiy from basic research work to design of a commercial plant using this approach for a brand new process risks a significant failure. Hence, one or more intermediate size units are usually desirable to demonstrate process feasibiUty as well as to determine safe scale-up factors. 

Scale-up is the process of developing a plant design from experimental data obtained from a unit many orders of magnitude smaller. This activity is considered successful if the commercial plant produces the product at plaimed rates, for plaimed costs, and of desired quaUty. This step from pilot plant to full-scale operation is perhaps the most precarious of all the phases of developing a new process because the highest expenses ate committed at the stages when the greatest risks occur. 

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