Heat radiation drying

Heat loss, dry The heat exchange that fakes place from the human body to the surroundings by convection, radiation, and conduction but not by evaporation. 

WTien steam is injected at a rate of approximately 0.3 pounds of steam per pound of flare gas, the fraction of heat radiated is decreased by 20%. T is based on hydrocarbon flame at 2240°F, 80 °F dry buib air, relative humidity > 10%, distance from flame between 100 and 500 feet, and is acceptable to estimate under wide conditions. 

Pharmaceuticals for injection must be presented in a sterile form. Sterility may be achieved by filtration through 0.22 pm filters under aseptic conditions, or by steam, dry heat, radiation or gas sterilisation methods, which may be applied to packaged products. Irrespective of the method, the process must be validated and monitored to assure its effectiveness. As discussed in Chapter 2, this is an example of a process that cannot be assured by verification testing because of its destructive nature. 

Parenteral drug products are required to be sterile. There are principally five different ways to sterilize a product. These are steam, dry heat, radiation, gas. 

Fig. 4.2. Waste heat boiler for a copper smelting flash furnace (Peippo et al, 1999). Note, left to right (i) flash furnace gas offtake (ii) boiler radiation section with water tubes in walls (iii) suspended water tube baffles in radiation section to evenly distribute gas flow (iv) convection section with hanging water tubes. Steam from the boiler is used to generate electricity, to power the acid plant s main blower and for general heating and drying.

Description A tray or compartment dryer is an enclosed, insulated housing in which solids are placed upon tiers of trays in the case of particulate solids or stacked in piles or upon shelves in the case of large objects. Heat transfer may be direct from gas to sohds by circulation of large volumes of hot gas or indirect by use of heated shelves, radiator coils, or refractory wmls inside the housing. In indirect-heat units, excepting vacuum-shelf equipment, circulation of a small quantity of gas is usually necessary to sweep moisture vapor from the compartment and prevent gas saturation and condensation. Compartment units are employed for the heating and drying of lumber, ceramics, sheet materms (supported on poles), painted and metal objects, and all forms of particulate solids. 

The best approach to assessing problems with respect to a terminal sterilization method (i.e., moist heat, dry heat, radiation, and chemical methods) is to first establish the qualification, validation and stability of the pharmaceutical process prior to conducting a given sterilization procedure. 

Parenteral drug products are required to be sterile. There are principally five different ways to sterilize a product. These are steam, dry heat, radiation, gas and filtration. Selection of which method to use is based on the product that requires sterilization. For example, protein-based drugs are heat-sensitive, so the normal means for sterilizing these products is filtration. The rationale for sterilization validation is to show the reduction in microbial load or destruction of biological indicators. 

Mackey, B.M. and Derrick, C.M. 1982. The effect of sublethal injury by heating, freezing, drying and gamma-radiation on the duration of the lag phase of Salmonella typhimurium. Journal of Applied Bacteriology 53 243-251. 

Another alternate involves the post-drying of the film via crosslinking. Any number of reactions can be used, including double bonds pendent to the chain, or condensable groups. Heat, radiation, or high temperature peroxides might be used. If two different latexes, or core-shell stmctures are present, then the product will be an IPN. 

XRD patterns were recorded on a Philips PW 1710 instrument using Cu K i radiation (A. = 0.15418 A, 40 kW, 25 mA). N2 sorption experiments at 77 K were carried out with a Sorpty 1750 instrument (Carlo Erba Strumentazione) and specific surface areas (SS) calculated using the BET method (Table 1). Absorption/transmission IR spectra were run at RT on a Perkin-Elmer FT-IR 1760-X spectrophotometer equipped with a Hg-Cd-Te cryodetector. For IR analysis powders were pelletted in self-supporting discs (10-15 mg cm ), activated in vacuo at increasing temperature up to 823 K, heated in dry O2 at the same temperature and cooled down in oxygen or subsequently reduced in H2 at 623 K and outgassed at the same temperature. CO and NO (Matheson C.P.) were used as probes. 

Sterilization in place—Closed systems such as process vessels, dryers, centrifuges, isolators, and other items should be subjected to a validated sterilization procedure, which assures that all internal surfaces have been rendered free of microorganisms. Sterilization-in-place (SIP) procedures reduce the number of aseptic manipulations necessary to ready the equipment for use in the aseptic production processes and as such are considered preferable to aseptic assembly of systems from individually sterilized components (25). The SIP procedure should allow the system to maintain sterility until ready for use without aseptic manipulations. Sterilization-in-place procedures could employ steam, gas, dry heat, radiation, chemical agents, or other validateable sterilization procedure. 

Deng, Y., Y. Liu, B. Qian, S. Su, J. Wu, X. Song, and H. Yang, 2011b. Impact of far-infrared radiation-assisted heat pump drying on chemical compositions and physical properties of squid (Hlex illecebrosus) fillets. European Food Research and Technology, 232(5), 761-768. 

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