Basic Process Technology

Heat transfer, from the hot air in the cavity and from the wall of the mold to the powder, melts the polymer which sticks to the hot cavity (Fig. 6.42). It results in the formation of an even coating on the interior wall of the cavity. The mold is cooled while it is rotated to retain the uniform wall thickness. Finally, after the polymer has solidified, the rigid part is removed from the mold. Volatile material formed during the heating period is removed from a vent port. The rotation rate, temperature, heating rate, and cooling rate are controlled throughout the process. 

The rotational molding process takes place in two stages. During the first stage the polymer melts, sinters, and densifies, while in the second stage the melt flows on the walls of the mold and fills all channels, undercuts, and other cavities in the geometry of the 

This method is ideally suited to the casting of spherical shapes, but the outer shape may be modified with the use of special techniques. Normally, metal molds are used and plastic is poured into the rotating mold that may spin about a horizontal, inclined, or vertical axis. The centrifugal force, even though minor relative to gravity, improves both homogeneity and accuracy. 

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The basic process technology in vaccine production consists of fermentation for the production of antigen, purification of antigen, and formulation of the final vaccine. In bacterial fermentation, technology is weU estabHshed. For viral vaccines, ceU culture is the standard procedure. Different variations of ceU line and process system are in use. For most of the Hve viral vaccine and other subunit vaccines, production is by direct infection of a ceU substrate with the vims. 

Chemomechanical polishing, which combines mechanical abrasion and chemical etching, is a basic processing technology for the production of flat, defect-free reflective surfaces [215], The polishing proceeds by a combination of... 

There are many variations of the basic process and the patent Hterature is extensive. Several key patents describe the technology (16). The process steps are oxidation of cumene to a concentrated hydroperoxide, cleavage of the hydroperoxide, neutralization of the cleaved products, and distillation to recover acetone. 

Fabrication technologies for ah electronic ceramic materials have the same basic process steps, regardless of the appHcation powder preparation, powder processing, green forming, and densiftcation. 

Russian Process Technology. Magnesium production ia the former Soviet Union is apparently done via molten chloride electrolysis (29,30). The basic process uses camaOite [1318-27-0], MgCl2 KCl 6H20, either from natural deposits or as a by-product of processiag natural salt deposits, as its... 

Globalization creates a need to source complex products with a high degree of consistency across the world [291], This, in turn, demands a well-defined and transferable process technology. A massive, local customization requires product availability in great variety close to the customer, demanding process intensification, modular operations, transportable plant, and fast response and product changeover. Multifunctionality demands a wider space in formulations and a chemistry set to deliver dial-in fimctionality , which needs assembly from a consistent set of basic materials. 

Integrated vapor extraction and steam vacuum stripping can simultaneously treat groundwater and soil contaminated with VOCs. The system developed by AWD Technologies consists of two basic processes a vacuum stripping tower that uses low-pressure steam to treat contaminated ground-water and a soil gas vapor extraction/reinjection process to treat contaminated soil. The two processes form a closed-loop system that provides simultaneous in situ remediation of contaminated groundwater and soil with no air emission. 

The documentation should include the basic process knowledge and design considerations that form the foundation for facility design and operation. Prior to design, it is essential that this documentation be as complete as possible, since the identification and control of chemical reactivity hazards will be developed from this information. As subsequent knowledge is obtained or developed as a result of process or technology modification, it should also be incorporated into the documentation and carefully reviewed. 

It is apparent that around 1925 distillation equipment in the petroleum industry varied in design and complexity from the simple horizontal shell stills with fractional vapor condensation to the continuous pipe stills with the progenitor of the present bubble cap fractionating columns. The basic processing principles were being rapidly extended, and the foundation was well established for the further development of distillation technology. 

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