Mist and Spray

Fuels such as diesel and kerosene readily absorb hydrocarbon vapors, the total uptake and absorption rate depending on both chemical and physical factors. If a soluble test gas is introduced above a charged test oil the concentration of flammable test gas therefore decreases with time. Liquid mist and spray produced by charged liquid increase the absorption rate relative to a quiescent liquid surface. As discussed in A-5-4, absorption could lead to an underestimation of test gas MIE near the liquid surface unless the rate of test gas introduction is sufficiently high to offset the rate of removal. Table 3-8.1.2 shows solubilities of a selection of gases in a mineral-based transformer oil at ambient temperature and pressure [200]. 

The complexity of equipment required to arrest mists and sprays also increases with a reduction... 

Mists and Sprays - There are numerous industrial chemical operations which involve liquid-in-gas dispersions. These operations generate mists and sprays that consist of particles in diameter ranges of 0.1 to 5,000 fim. Engineers most commonly encounter spray droplets which are particles often formed unintentionally in chemical plant operations. For example, vapors or fumes may condense onto piping, ducts, or stack walls. Under such conditions liquid films form. 

Burgoyne, J. H. 1963. The flammability of mists and sprays. Second Symposium on Chemical Process Hazards. 

Mist and spray humidifiers, unless the water is pure, will leave a powder deposit of these salts in the conditioned space. 

Mists and sprays also affect flammability limits.12 For suspensions with drop diameters less than 0.01 mm, the LFL is virtually the same as the substance in vapor form. This is true even at low temperatures where the liquid is nonvolatile and no vapor is present. Mists of this type are formed by condensation. 

J. H. Borgoyne, The Flammability of Mists and Sprays, Chemical Process Hazards (1965), 2 1. 

Gas Sampling The sampling of gases containing mists and sprays may be necessary to obtain data for collection-device design, in which case particle-size distribution, total mass loading, and gas volume,... 

Serves as a guard against the hazards of impact, splashes from chemicals or molten metal, liquid droplets (chemical mists and sprays), dust, gases and welding arcs. Eye protectors include safety spectacles, eye-shields, goggles, welding filters, face shields and hoods (Fig. 1.7). 

Mist is composed of suspended hquid droplets generated by condensation from the gaseous to the hquid state as by atomizing, foaming, or splashing. Examples of mists are oil mists, chromium trioxide mist, and sprayed paint. 

Flying n. A condition wherein a fine mist or spray of ink is thrown off rapidly moving ink rollers. Syn misting and spraying. 

Vac-All tracks are not vacuum tracks. They convey solid material with a high-velocity air stream. Trucks of this type should not be used for liquid hydrocarbons or flammable liquids because the high velocity of the air can create ignitable mists and sprays.)... 

Uses Drift controi agent for improving deposition and retarding mist and spraying operations... 

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