Generation, rate

A reactor system is shown in Figure 2 to which the HAZOP procedure can be appHed. This reaction is exothermic, and a cooling system is provided to remove the excess energy of reaction. If the cooling flow is intermpted, the reactor temperature increases, leading to an increase in the reaction rate and the heat generation rate. The result could be a mnaway reaction with a subsequent increase in the vessel pressure possibly leading to a mpture of the vessel. 

If a self-sustained oxidation is carried out under limiting rate conditions, the hydroperoxide provides the new radicals to the system (by reaction 4 or analogues) and is maintained at a low concentration (decomposition rate = generation rate). For these circumstances, the rate equation 9 holds, where n = average number of initiating radicals produced (by any means) per molecule of ROOH decomposed and / = fraction of RH consumed which disappears by ROO attack (25). 

Fig. 15. Temperature vs heat generation or removal in estabHshing stationary states. The heavy line (—) shows the effect of reaction temperature on heat-generation rates for an exothermic first-order reaction. Curve A represents a high rate of heat removal resulting in the reactor operating at a low temperature with low conversion, ie, stationary state at a B represents a low rate of heat removal and consequently both a high temperature and high conversion at its stationary state, b and at intermediate heat removal rates, ie, C, multiple stationary states are attainable, c and The stationary state at c ...

As with generation rates, the chemical composition of MSW varies significantly with local socioeconomic and demographic conditions. The average chemical composition of MSW in the United States is given in Table 1 (16). 

Constmction and dem olition (C D) debris is a potentiahy large source of recyclables. However, as of 1995, generation rates and ferrous scrap content were not weh estabUshed and estimates were highly variable. Eerrous materials in C D debris are typicahy reinforcing bars, wire mesh, and stmctural steel. Some of the scrap is sold for recycling once concrete is effectively removed and the scrap is sized to specification (17). 

By performing a material balance in conjunc tion with a pollution prevention assessment, the amount of waste generated becomes known. The success of the pollution prevention program can therefore be measured by using this information on baseline generation rates (i.e., that rate at which waste is generated without pollution prevention considerations). 

Sohd wastes, as noted previously, include all sohd or semisolid materials that are no longer considered of sufficient value to be retained in a given setting. The types and sources of solid wastes, the physical and chemical composition of sohd wastes, and typical solid-waste generation rates are considered in this subsection. 

Quantities of Solid Wastes Representative data on the quantities of sohd wastes and factors affecting the generation rates are considered briefly in the following paragraphs. 

Typical Generation Rates Typical unit waste-generation rates for selected industrial sources are reported in Table 25-54. Because waste-generation practices are changing so rapidly, the presentation of typical waste-generation data may not be rehable. 

TABLE 25-54 Unit Solid-Waste-Generation Rates for Selected Industrial Sources... 

R, = volume generation rate, ftVmin P = volumetric expansion coefficient, ftVlb-°F Q = heat input rate, Btu/min Cp = hquid heat capacity, Btu/lb-°F... 

Motors and generators ratings, constniction, testing and performance... 

NEMA/MG-1/1993 NEMA/MG-2/1989 Motor and generators ratings, construction, testing and performance Safety Standards (enclosures) for construction and guide for selection, installation and use of rotating machines ... 

Moioi s iind generators ratings, construeiion. testing, and i erfonnance... 

Iq = generator rated current in A. eos (p = generator rated p.f. which is quite high compared to a motor, as the reactive power is now supplied by the external source. 

Cut-oul wind speed is the maximum w ind speed beyond which the prime mover may overspeed above its permissible limits. As the structure and the blades are designed for a particular maximum speed, a wind speed higher than this may exceed their mechanical endurance and become unsafe. At this speed the brakes apply and the machine is disconnected from the grid. The cut-in and cut-out speeds define the wind speed limits within which the turbine will work safely through the generator. Rated wind speed is the speed at which the prime mover rotates at the rated negative slip and generates the rated power. 

ANSI C.37.47/1992 Specifications for distribution fuse disconnecting switches, fuse supports and current limiting fuses Motors and generators ratings, costruction. testing and performance... 

To determine the grounding parameters, consider a generator rated for 200 MW, 15 kV and the ground fault current limited to 15 A. Considering GFF as -J3, the voltage ratio of the grounding transformer with a 220 V secondary will be... 

While high defect generation rates in the shock can qualitatively be applied to explain the approximately sevenfold yield increase in copper to 210 MPa following loading to a 10 GPa shock [13], significant shock har-... 

Temperature gradient normal to flow. In exothermic reactions, the heat generation rate is q=(-AHr)r. This must be removed to maintain steady-state. For endothermic reactions this much heat must be added. Here the equations deal with exothermic reactions as examples. A criterion can be derived for the temperature difference needed for heat transfer from the catalyst particles to the reacting, flowing fluid. For this, inside heat balance can be measured (Berty 1974) directly, with Pt resistance thermometers. Since this is expensive and complicated, here again the heat generation rate is calculated from the rate of reaction that is derived from the outside material balance, and multiplied by the heat of reaction. 

Heat generation rate equals the heat transfer rate ... 

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