Other Types of Equipment

probes, and cup-horns are common laboratory equipment. For large-scale uses, other types of emitters are preferred. Whistles (Fig. 9) can be used for processing liquid mixtures or suspensions. The principle consists of injecting the mixture under a few bar overpressure through a variable slit onto a vibrating blade located in a resonant cavity. The advantage is the simplicity and the compatibility with a flow process the inconvenience is the erosion undergone by the blade. 

Equipment involving parallel vibrating plates is probably the best option for online use, the product being treated homogeneously during its transfer through the reactor whose walls are vibrating (Fig. 10).25 

When the plates are close together, the attenuation of the sound is minimal (Fig. 11) and the rules followed in regular sonicated systems (baths, cup horns) involving large volumes and standing wave patterns are not valid in this case. 

The RUM (Reverberating Ultrasonic Mixer), with its two frequencies of 16 and 20 kHz produces a beat frequency of 4 kHzThe two different waves create a larger number of different cavitating bubbles than a single one. 

Where the plants distilled grow wild it is usually necessary to move the stills from place to place as the plant supply is e.xhausted. Such itinerant stills are usually of the simplest types. They are probably less efficient than the commercial stills used for widely cultivated volatile-oil crops, but appear to serve best the purpose for which they are designed. 

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Product Quality Considerations of product quahty may require low holdup time and low-temperature operation to avoid thermal degradation. The low holdup time eliminates some types of evaporators, and some types are also eliminated because of poor heat-transfer charac teristics at low temperature. Product quality may also dic tate special materials of construction to avoid met hc contamination or a catalytic effect on decomposition of the product. Corrosion may also influence evaporator selection, since the advantages of evaporators having high heat-transfer coefficients are more apparent when expensive materials of construction are indicated. Corrosion and erosion are frequently more severe in evaporators than in other types of equipment because of the high hquid and vapor velocities used, the frequent presence of sohds in suspension, and the necessary concentration differences. 

The sequencing of distillation columns and other types of equipment for the separation of multicomponent mixtures has received much attention in recent years. Although one separator of complex design can sometimes be devised to produce more than two produc ts, more... 

Like any other type of equipment, clutches require regular inspection and maintenance. The sections to follow describe the general maintenance practices that are required to keep positive and friction clutches functioning properly. 

Relief system The network of components around a relief device, including the pipe to the relief, the relief device, discharge pipelines, knockout drum, scrubber, flare, or other types of equipment that assist in the safe relief process. 

Other types of equipment available to investigate the gas evolution are various autoclave tests (Section 2.3.3.2), isoperibolic autoclave tests (Section 2.3.1.2), and closed Dewar tests (Section 2.3.2.2). Mass flux data are also required in designing any vent facilities (Chapter 3). 

Automatic, mechanical, or electronic equipment, or other types of equipment or related systems that perform a function satisfactorily may be used in the eompounding of drug products. If such equipment is used, it shall be routinely inspeeted, ealibrated (if neeessary), or checked to assure proper performance. 

Other types of equipment that can yield even higher efficiency values are roller and flow coating machines (90 to 98%) and electrocoating systems (90 to 99%). Roller and flow coating machines, however, are limited in their applicability based on the shape of the parts. Electrocoating systems require a shift from solvent-based to waterbased paint. 

Consider general ways in which the design criteria can be achieved, specification of other types of equipment, manufacturer s data, economic considerations, materials and fabrication requirements for the design, etc. 

In collaboration with Alexander Gorbach, NIH, we have initiated a study of the spatial patterns in the nephron synchronization. This study involves the use of infrared cameras or other types of equipment that can measure variations in the blood supply by small (0.01°C) fluctuations in the temperature at the surface of the kidney. It is also of interest to study how the large amplitude oscillations in pressure, fluid flow, and salt concentration at the entrance of the distal tubule influence the delicate hormonal processes in that part of the kidney, to establish a more quantitative description of some of the mechanisms involved in the development of hypertension, and to examine the effects of various drugs. 

The earliest agglomeration equipment consisted simply of solid-liquid mixers and, in common with newer designs, provided the mechanical means by which particles were brought into contact and densified into larger entities as the cohesive forces came into operation. Various other types of equip-... 

Valves. It is desirable and inherently safer to use fire-tested valves whenever it is necessary to isolate flammable or combustible fluids in a pipeline or tank or other type of equipment. Fire-tested valves were formerly called fire-safe valves. They were not really firesafe, and the name has been changed to fire-tested valves. Fire-tested valves should be considered for handling most fluids that are highly flammable, highly toxic, or highly corrosive and that cannot be permitted to escape into the environment. 

If other types of equipment and experimental procedures are used, one may also have to take into account ... 

Heat transfer is more of a problem in batch reactors than in other types of equipment because of their small surface-to-volume ratio and because rates are high initially. Effective stirring is essential. If the reaction is highly exothermic or endothermic, cooling or heating coils are usually needed. 

Labor costs vs. capital costs—Some types of equipment are very labor intensive, but the capital costs for installation are relatively cheap. Other types of equipment have low labor requirements but are more expensive. The trade-offs between labor and capital costs need to be carefully analyzed when selecting the appropriate equipment. 

Their results, using the three test criteria, are summarized in Table V. The large rotating cubes are seen to have given the best results. However, since several sizes were not tried for the other types of equipment, no positive conclusions can be made on the basis of the data presented. 

Corrosion—Corrosion may influence the selection of the evaporator type, since expensive materials of construction usually dictate that evaporator designs allowing high rates of heat transfer are more cost effective. Corrosion and erosion are frequently more severe in evaporators than in other types of equipment, because of the high liquid and vapor velocities, the frequent presence of suspended solids, and the high concentrations encountered. 

Other types of equipment such as static (motionless) mixers, rotor-stator mixers, and impingement mixers are used to create dispersions (see Section 9.9). 

Such collection systems were initiated on a national level in Sweden and Germany. In other countries, private initiatives were leading to the opening of collection systems for cordless power tools and other types of equipment ECOELIT (Italy), BOSCH (Germany), REBAT (UK), ECOVOLT (France) are representatives of these initiatives. 

Automatic, mechanical, or electronic processing equipment, or other types of equipment induding computers, used in the manufacture of APIs and intermediates should be routinely calibrated, inspected, and checked to ensure proper performance. Written records of those calibration checks and inspections should be maintained. 

Other types of equipment than motors are often chosen with type n enclosmes, e.g. luminaries, junction boxes, terminal boxes, if the designer can be sure that they will be located in a Zone 2 or non-hazardous area. 

Absorption processes are often technically realized in packed columns or, more scarcely, in tray columns. For chemical absorption, however, many other types of equipment are used in industiy, e.g., spray tower, venturi scmbber, bubble columns, etc. 

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