Dry solids

Drum dryers are shown in Fig. 3.15c. his consists of a heated metal roll. As the roll rotates, a layer of liquid or slurry is dried. The final dry solid is scraped off the roll. The product comes ofiF in flaked form. Drum dryers are suitable for handling slurries or pastes of solids in fine suspension and are limited to low and moderate throughput. 

Warm concentrated H2SO4 on the dry solid HF evolved HCl evolved HBr. SO 2 and Bt2 evolved SO2, H2S. and I2 evolved... 

Dry-weight basis expresses the moisture content of wet sohd as kilograms of water per kilogram of bone-dry solid. 

FIG. 12-40 Two typ es of internal moisture gradients obtained in drying solids,... 

Material Physical form Moisture contents, kg/kg dry solid Inlet-air temperature, K Depth of bed, cm Loading, kg product/m Air velocity, m/s X 10 Experimental drying time, s X 10 ... 

Typical operating data for cocurrent rotary dryers are given in Table 12-18. (Note that the driving force AT must be based on wet-bulb depression and not on material temperatures. Use of material temperatures, particrrlariy when the dry solids are superheated after drying, will yield conservative results.)... 

Drying Fhiidized-bed units for drying solids, particularly coal, cement, rock, and limestone, are in general acceptance. Economic-considerations make these units particularly attrac tive when large tonnages of solids are to be handled. Fuel requirements are 3.3 to 4.2 MJ/kg (1500 to 1900 Btu/lb of water removed), and total power for blowers, feeders, etc., is about 0.08 kWh/kg of water removed. The maximum-sized feed is 6 cm (IV2 in) X 0 coal. One of the major advantages of this type of dryer is the close control of conditions so that a predeterminea amount of free moisture may be left with the solids to... 

Coating Fluidized beds of thermoplastic resins have been used to facilitate the coating of metallic parts. A properly prepared, heated metal part is dipped into the fluidized bea, which permits complete immersion in the dry solids. The heated metal fuses the thermoplastic, forming a continuous uniform coating. 

General References Dry Solids, Paste and Dough Mixing Equipment Test-... 

Dry Solids or Filtrate Rate Filtration rate, expressed either in terms of diy solids or filtrate volume, may be plotted as a function of time on log-log paper. However, it is more convenient to delavthe rate calculation until the complete cycle of operations has been defined. 

Area required to filter 15 metric tons of dry solids per hour = 15 X 1000/162 = 92.6 m . The practical choice would then he the nearest commercial size of filter corresponding to this calculated area. 

Objective Determine the filter size and vacuum capacity required to dewater and wash 15 mtph of dry solids while producing a final washed cake with a moisture content of 25 wt % and containing 0.10 wt % TDS based on dry cake solids. 

Requiring nitrogen inerting when pouring dry solids into flammable solvents... 

Potassium picrate [573-83-1] M 267.2. Crystd from water or 95% EtOH, and dried at room temperature in vacuum. It is soluble in 200 parts of cold water and 4 parts of boiling water. THE DRY SOLID EXPLODES WHEN STRUCK OR HEATED. 

One of the methods of controlling air pollution mentioned in the previous chapter was pollution removal. For pollution removal to be accomplished, the polluted carrier gas must pass through a control device or system, which collects or destroys the pollutant and releases the cleaned carrier gas to the atmosphere. The control device or system selected must be specific for the pollutant of concern. If the pollutant is an aerosol, the device used will, in most cases, be different from the one used for a gaseous pollutant. If the aerosol is a dry solid, a different device must be used than for liquid droplets. 

CAUSTIC SODA, DRY, SOLID CAUSTIC SODA, SOLUTION CDEC see SULFALLATE... 

Chemical Reactivity - Reactivity with Water Reacts violently with water as a dry solid or when dissolved in ether. The hydrogen produced by the reaction with water is a major hazard and necessitates adequate ventilation Reactivity with Common Materials Can burn in heated or moist air Stability During Transport Normally stable imstable at high temperatures Neutralizing Agerus for Acids and Caustics Not pertinent Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Solids handling frequently has the potential for dusting, which can lead to potential health and explosion hazards. Handling solids in the form of larger particle size granules or pellets rather than a fine powder reduces the potential for worker exposure. Worker exposure hazards are reduced by formulating dyes as liquids or wet pastes rather than dry solids or powders (Burch, 1986). 

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