Dusting of solids

Grade E Mg powd and BkPdr dust when exposed in layers. Dust of solid proplnts can also be ignited from the spark that can accumulate on a person, and conductive floors Sc shoes must be used when the dust is present. In addn, dust-air mixts of Amm Picrate, Tetryl, Tetrytol dust of solid proplnts are sensitive to static elec discharges. Many flammable liquids Sc air mixts ( ether, ethyl alcohol, ethyl acetate, acetone gasoline) can also be ignited by static discharge from a person (Refs 1 3)... 

The dispersal of material by spraying or by dusting of solid particles plays an important role in combustion technology. Large industrial boilers or furnaces employ oil fuel... 

Preparation - Avoid dusting of solid substances 11 In-process controls ... 

Dust Separation It is usuaUy necessaiy to recover the solids carried by the gas leaving the disengaging space or freeboard of the fluidized becl GeneraUy, cyclones are used to remove the major portion of these sohds (see Gas-Sohds Separation ). However, in a few cases, usuaUy on small-scale units, filters are employed without the use of cyclones to reduce the loading of solids in the gas. For high-temperature usage, either porous ceramic or sintered metal has been employed. Multiple units must be provided so that one unit can be blown back with clean gas while one or more are filtering. 

Dust collection is concerned with the removal or collection of solid dispersoids in gases for purposes of ... 

Moisture or liquid content of solids. Often a small amount of liquid is added for dust reduc tion or special requirements (such as oils for cosmetics). The resultant material may still have the appearance of a diy solid rather than a paste. 

Contact Electrification This form of charging involves the contact and separation of solid-sohd, sohd-hquid, or hquid-liqmd surfaces. Pure gases do not cause charging unless they cany droplets or dust particles. 

Dusts from solid Design operation to minimize/eliminate dusts or filling, vapors vapors from liquid filling., proper personal protective equipment Ensure proper design of local ventilation ACGIH 1986 CCPS G-3 CCPS G-22 CCPS G-23 CCPS G-29... 

Certain oxidizing/redueing eompounds and salts whieh, in the form of solid (bulk or dust) or as solution, ean produee iiTitation by thermal burns. 

Particle Sampler an instrument to measure particulate matter in ambient air. Particulate Matter dust, soot, other tiny bits of solid materials that are released into and move around in the air. See also fine particle, PM,o. 

Dust The solid particulate matter formed by the breaking up of larger particulates by mechanical action. The particles range up to 75 pm in diameter larger particles are classified as grit. 

Most everyone knows that dusts—fine particles of solid—can explode, but not everyone is aware that mists—fine droplets of liquid—can explode just as easily and that they can explode at temperatures fai below the flash point of the bulk liquid or vapor [19]. 

Separatory operations may isolate the more hazardous components from tlie diluent or inert. Screening of solids, in effect, separates tlie more hazardous dusts (small particles and fines) from the less liazardous larger pieces of material. Centrifuges, like all liigh-speed equipment, must be securely positioned to provide protection to all persomiel working in the vicinity. 

Vei y small solid fuel particles such as sawdust, agricultural grains, or coal dust can sustain flames when they are suspended in air. In fact, very serious fires have occurred in grain storage towers and coal mines because of the flammability of suspended dusts. The combustion of the individual particles follows the usual pattern of solid particle burning— devolatization and char burning. The combustion of the whole cloud of particles is similar to spray combustion and its characteristics depend on the nature of the fuel, size of the particles, and the number of particles in a given volume. 

These operations may sometimes be better kno Ti as mist entrainment, decantation, dust collection, filtration, centrifugation, sedimentation, screening, classification, scrubbing, etc. They often involve handling relatively large quantities of one phase in order to collect or separate the other. Therefore the size of the equipment may become very large. For the sake of space and cost it is important that the equipment be specified and rated to Operate as efficiently as possible [9]. This subject will be limited here to the removal or separation of liquid or solid particles from a vapor or gas carrier stream (1. and 3. above) or separation of solid particles from a liquid (item 4j. Reference [56] is a helpful review. 

There are two types self-induced spray and pressure spray. Many designs have been developed to suit specific dust or fume problems, and it is now possible to use wet collectors on the treatment of solids and fumes down to very small particle sizes. 

Now is the time to dust off the algebra and put it to work. Suppose we designate the solubility of cuprous chloride in water by a symbol, s. This symbol s equals the number of moles of solid cuprous chloride that dissolve in one liter of water. Remembering equation (23), we see that s moles of solid cuprous chloride will produce s moles of cuprous ion, Cu+, and s moles of chloride ion, Cl-. Hence these concentrations must be equal, as shown below. 

Dust content, of solid fuels Dutch oven furnace DVGW Guidelines... 

For the evaluation of preparations to be used against pathogenic fungi, suitable cultures of these pathogens should be used. To test substances intended to inhibit general contaminants, cultures of common fungi obtained conveniently by exposing Petri dishes of solid media to the atmosphere may be used, or alternatively dust or soil may be used as a source of a mixed inoculum. 

Many mechanical separations involve the movement of solid particles or liquid drops through a fluid. The fluid may be gas or liquid, and it may be flowing or static. As some assortment of examples mention may be made of the removal of dust and fumes from air or flue gas, the removal of solids from liquid wastes to permit discharge into public domain, and of the recovery of acid mists from an acid plant gaseous wastes. 

Solid effluents arising from metallurgical operations occur principally in two forms fine particulate solids or dusts, and solid wastes. As an example, blast furnace gas may contain up to 170 kg of dust per ton of pig iron produced. Suitable methods must be devised for processing the solid effluents for two reasons (i) to prevent pollution of the environment and (ii) to recover their valuable content, if any. As far as the latter is concerned, reference may be drawn, as an example, to the recovery of rhenium from the exit gas from molybdenite roasting in a multiple-hearth furnace. 

Wear dust- and splash-proof safety goggles where there is any possibility of solid CN or liquids containing CN may contact the eyes wear face shield wear appropriate protective mask. 

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