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Pollutants heat capacity

A durable will have a surface temperature resultant of several factors including the surface finish, color, heat capacity, and thermal conductivity of the material used to make the durable. A decrease in thermal oxidative stability over time can result from consistently high surface temperatures. Frequent exposure to precipitation and high humidity can accelerate the deterioration of the surface of a durable. Wind transfers dust and pollutants that cover the surface of a durable. While some limited protective effects from particulate coatings exist, some dusts and volatile pollutants like sulfur dioxide can initiate or catalyze chemical reactions on a durable. [Pg.3109]

Adsorption (qv) of gases has been reviewed (40,50) (see also Adsorption, gas separation). Adsorption, used alone or in combination with other removal methods, is excellent for removing pollutant gases to extremely low concentrations, eg, 1 ppmv. When used in combination, it is typically the final step. Adsorption, always exothermic, is even more attractive when very large gas volumes must be made almost pollutant free. Because granular adsorbent beds ate difficult to cool because of poor heat transfer, gas precooling is often practiced to minimize adsorption capacity loss toward the end of the bed. Pretreatment to remove or reduce adsorbable molecules, such as water, competing for adsorption sites should also be considered (41). [Pg.387]

Also important are the heat exchanger tubes. In the first instance a centrifugal fan was placed directly on the distributor duct. However, the stall air sucked in is so polluted with dust, feathers, etc. that the holes are very soon clogged up. Installation of a dust filter quickly gives rise to a loss of capacity. Dust filters are no solution to the problem, in particular from the viewpoint of practical objections and the high investments involved. [Pg.181]

Chemical reactors are the most important features of a chemical process. A reactor is a piece of equipment in which the feedstock is converted to the desired product. Various factors are considered in selecting chemical reactors for specific tasks. In addition to economic costs, the chemical engineer is required to choose the right reactor that will give the highest yields and purity, minimize pollution, and maximize profit. Generally, reactors are chosen that will meet the requirements imposed by the reaction mechanisms, rate expressions, and the required production capacity. Other pertinent parameters that must be determined to choose the correct type of reactor are reaction heat, reaction rate constant, heat transfer coefficient, and reactor size. Reaction conditions must also be determined including temperature of the heat transfer medium, temperature of the inlet reaction mixture, inlet composition, and instantaneous temperature of the reaction mixture. [Pg.218]

When the actual temperature-decline-with-altitude is greater than 9.8°C/1000 m, the atmosphere is unstable, the c s become larger, and the concentrations of pollutants lower. As the lapse rate becomes smaller, the dispersive capacity of the atmosphere declines and reaches a minimum when the lapse rate becomes positive. At that point, a temperature inversion exists. Temperature inversions fomi every7 evening in most places. However, these inversions are usually destroyed the next morning as the sun heats the earth s surface. Most episodes of high pollutant concentrations are associated with multiday inversions. [Pg.367]


See other pages where Pollutants heat capacity is mentioned: [Pg.184]    [Pg.756]    [Pg.902]    [Pg.256]    [Pg.480]    [Pg.55]    [Pg.230]    [Pg.1984]    [Pg.581]    [Pg.5]    [Pg.305]    [Pg.472]    [Pg.410]    [Pg.73]    [Pg.165]    [Pg.218]    [Pg.416]    [Pg.86]    [Pg.251]    [Pg.60]    [Pg.195]    [Pg.409]    [Pg.743]    [Pg.288]    [Pg.547]    [Pg.195]    [Pg.472]    [Pg.5]    [Pg.305]    [Pg.74]    [Pg.235]    [Pg.349]    [Pg.79]    [Pg.165]    [Pg.470]    [Pg.4]    [Pg.79]    [Pg.235]    [Pg.1855]    [Pg.82]   


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Heating pollutants

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