Pilot Plant Quality Control

In the EU Project JOR3-CT95 0025, co-ordinated by VTT Energy, i.a. the quality of pyrolysis oil of pilot plants was controlled, using Swedish pine as raw material [12]. The oils produced were used in combustion tests at Oilon Oy. 

If the product is to be used for pharmaceuticals the GMP rules must be obeyed during plant operation. All chemicals to be tested in clinical studies with humans must be prepared according to GMP. This leads to very detailed documentation since if you haven t documented it, you haven t done it . All procedures for manufacturing and changes in procedures are subject to approval by quality control departments. This decreases the flexibility in process development. Products that are contaminated too much must be reprocessed according to the GMP guidelines. All equipment to be used in the pilot plant must be validated before use. 

The electric furnace process (Fig. 11) for the conversion of phosphate rock into phosphorus was described by Horton et al. [15] in a paper that also presented the results of a pilot plant study of treating the wastes produced. The process, as well as the handling of the various waste streams for pollution control, are discussed in Section 9.5.2. In processing the phosphate, the major source of wastewater is the condenser water bleedoff from the reduction furnace, the flow of which varies from 10 to 100 gpm (2.3-22.7 m /hour) and its quality characteristics are presented in Table 7. 

The physical properties and specifications for the manufactured formulations should match those established earlier by the product formulator, the pilot plant staff, and the quality control department. Therefore, the product manufactured on a large scale should possess the appropriate quality properties. 

Abatement by the California Regional Water Quality Control Board, Central Valley Region, has included ditches to divert surface water from the mine workings, a seal at the mine adit, and operation of a pilot mine wastewater treatment plant to remove residual toxic heavy metals as part of contingency planning. 

Anon, "Pilot Plant Treatment of Mine Drainage, Walker Mine, Plumas County, Callfomle," Draft Report prepared for California Regional Water Quality Control Board, Central Velley Region, by Pearson and Associates, Richmond, California, Regional Board Project 1-043-150-0, March 1983. 

High quality optical fibers obtained using the PCVD method demonstrate that the plasma activated deposition fulfills the extreme requirements for optical fibers almost ideally. This is underlined by the optical properties of a large number of fibers prepared under the same PCVD conditions on a pilot plant scale which show a narrow distribution in their attenuation and pulse broadening values. This in turn is directly correlated with the good process control which is achievable. 

Besides analyzing and correlating data by statistical means, the chemical engineer also uses statistics in the development of quality control to establish acceptable limits of process variables and in the design of laboratory, pilot plant, and process plant (evolutionary operation) experiments. In the latter application, statistical strategy in the design of experiments enables the engineer to set experimental variables at levels that will yield maximum information with a minimum amount of data. 

Few mechanisms of liquid/liquid reactions have been established, although some related work such as on droplet sizes and power input has been done. Small contents of surface-active and other impurities in reactants of commercial quality can distort a reactor s predicted performance. Diffusivities in liquids are comparatively low, a factor of 10 less than in gases, so it is probable in most industrial examples that they are diffusion controlled. One consequence is that L/L reactions may not be as temperature sensitive as ordinary chemical reactions, although the effect of temperature rise on viscosity and droplet size can result in substantial rate increases. L/L reactions will exhibit behavior of homogeneous reactions only when they are very slow, nonionic reactions being the most likely ones. On the whole, in the present state of the art, the design of L/L reactors must depend on scale-up from laboratory or pilot plant work. 

Kim, W. H., et al. (1997). Pilot plant study on ozonation and biological activated carbon process for drinking water treatment. Water Science Technol, Proc. 1995 5th lAWQ Asian Regional Conf. on Water Quality and Pollut. Control, Eeb. 7-9, 1995, Manila, Philippines, 35, 8, 21-28. Elsevier Science Ltd., Oxford, England. 

Often the analysis of a compound is best left to specialists. Analytical chemists may be very helpful in developing an in-process assay for the laboratory or pilot plant and in purifying an impurity. Quality control (QC) chemists may be key in recognizing a new impurity in a manufacturing batch. Spectroscopists know how to get the best performance from their instruments. Good teamwork among the analysts and other chemists is essential to the efficient development of a process. 

Chemical synthesis can work beautifully on a small scale in the laboratory where the conditions can be meticulously controlled and the course of a reaction monitored in great detail, but it is not until a scale-up to the plant has been conducted that data on its robustness and sensitivity to various parameters will become obvious. Thus in parallel with the efforts put in to developing and optimizing the asymmetric step, comprehensive resources were invested in conducting trial runs on various scales in the pilot plant. A compilation of significant batches is shown in Tab. 1 together with conditions of operation and comments on the outcome. It is worth noting the increase in process performance quality over time as a result of development and optimizations exemplified, e.g., by a steady improvement in yield and % ee. 

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