Bubble caps Subject

Adsorbers, distillation colunuis, and packed lowers are more complicated vessels and as a result, the potential exists for more serious hazards. These vessels are subject to tlie same potential haz. uds discussed previously in relation to leaks, corrosion, and stress. However, llicse separation columns contain a wide variety of internals or separation devices. Adsorbers or strippers usually contain packing, packing supports, liquid distributors, hold-down plates, and weirs. Depending on tlie physical and chemical properties of the fluids being passed tlirough tlie tower, potential liazards may result if incompatible materials are used for llie internals. Reactivity with llie metals used may cause undesirable reactions, which may lead to elevated temperatures and pressures and, ullinialely, to vessel rupture. Distillation columns may contain internals such as sieve trays, bubble caps, and valve plates, wliicli are also in conlacl with tlie... 

Other Types of Wet Scrubbers. Plate towers, like sieve, valve, and bubble cap towers, and packed beds have been used in the past for dust collection but these are all subject to plugging. 

Alloy 400 exhibits excellent resistance to hydrofluoric acid solutions at all concentrations and temperatures, as shown in Figure 15.1. Again, aeration or the presence of oxidizing salts increases the corrosion rate. This alloy is widely used in HF alkylation, is comparatively insensitive to velocity effects, and is widely used for critical parts such as bubble caps or valves that are in contact with flowing acid. Monel 400 is subject to stress corrosion cracking in moist, aerated hydrofluoric or hydrofluorosilicic acid vapor. However, cracking is imlikely if the metal is completely immersed in the acid. 

One easily understands why, in this experiment, the bubbles of air which go up on the surface of mercury are not restricted to develop film segments of a sphere, but continue their upward progress by forming complete film spheres each bubble of air, after having formed a mercnrial cap, remains subjected, on behalf of the water, to an upwards push which is transmitted to it by the intermediary of mercury, and makes it overcome the capillary pressure exerted on it from top to bottom by the raised cap the... 

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