Maximum capacity

The surface production system consists of a series of equipment items, such as that illustrated below, which shows the maximum oil handling capacity of the items. The maximum capacity of the system is determined by the component of the system with the smallest throughput capacity. 

In order to carry out a distillation, the apparatus is completely assembled, the water pump turned on to its maximum capacity, and the screw clip on the capillary tube in the Claisen flask adjusted so that a gentle stream of air bubbles through the liquid (see Section 11,19 for details of the preparation of the capillary tube). The barometric pressure is read, and if the resulting vacuum deter mined from the reading on the mano meter is satisfactory (as estimated from the temperature of the tap water), the flask may be heated in an air (Fig. II,... 

Composite packagings with inner glass, porcelain, or stoneware receptacles maximum capacity 60 L (16 gal) and maximum net mass 75 kg (165 lb). 

Selection. The magnetic pulley width should match that of the belt. The face width is normally 51 mm wider than the belt width up to 1067 mm wide, and 76 mm on widths ia excess of 1219 mm. The speed of operation of the conveyor belt should be determined by calculating the maximum capacity to be handled. Using this iaformation, the diameter of the pulley required to handle the capacity can be determined (Table 2). The operating belt speed must be acceptable for the diameter selected. If the recommended belt speed is exceeded, the pulley diameter that can handle the belt speed must be used. 

Cobbers. Magnetic dmms used in cobbing services are designated to obtain maximum rejection of a nonmagnetic product and maximum recovery of the iron mineral. Typically, cobbers are appHed on a rod mill discharge product. Because the objective is to obtain maximum capacity, these dmms are 914 or 1219 mm in diameter and incorporate wear covers on the dmm shells to take the wear introduced by the relatively coarse feed size. 

The abihty to remove heat from electrophoretic systems has severely limited the maximum capacity of these systems in terms of how large or thick the systems can be. Electrophoretic separations have been performed on space flights because the effect of gravity in outer space is small and mixing from heating is negligible. Whereas electrophoresis in outer space has been accompHshed (10), the economics for a scaleable process have not (see Space processing). 

The two principal elements of evaporator control are evaporation rate a.ndproduct concentration. Evaporation rate in single- and multiple-effect evaporators is usually achieved by steam-flow control. Conventional-control instrumentation is used (see Sec. 22), with the added precaution that pressure drop across meter and control valve, which reduces temperature difference available for heat transfer, not be excessive when maximum capacity is desired. Capacity control of thermocompression evaporators depends on the type of compressor positive-displacement compressors can utilize speed control or variations in operating pressure level. Centrifugal machines normally utihze adjustable inlet-guide vanes. Steam jets may have an adjustable spindle in the high-pressure orifice or be arranged as multiple jets that can individually be cut out of the system. 

Install instrumentation to control the lain at maximum-capacity conditions. 

Flooding and Loading Since flooding or phase inversion normally represents the maximum capacity condition for a packed column, it is desirable to predict its value for new designs. The first generalized correlation of packed-column flood points was developed by Sherwood, Shipley, and Holloway [Ind. Eng. Chem., 30, 768 (1938)] on the basis of laboratory measurements primarily on the air-water system. 

Method of Feed The screening machine must be fed properly in order to obtain maximum capacity and efficiency. The feed should be spread evenly over the full width of the screen cloth and approach the screen surface in a direction parallel to the longitudinal axis of the screen and at as low a practical velocity as is possible. 

Magnetic pulleys. These vary in size from 0.203 to 1.219 m in diameter and from 2.03 to 1.526 m in width. The acceptable depth of the material on the conveyor belt depends on the diameter of the pulley and the linear velocity of the belt (see Table 19-18). Table 19-19 indicates the maximum capacity for such units. Depending on the apphcation, the correction factors given in Table 19-20 should be apphed. For sizing and maximum efficiency, multiply the actual volume of material to be handled by the correction factor shown and select the magnetic pulley having a capacity equal to or greater than the resultant volume. 

TABLE 19-19 Maximum Capacity for Magnetic Pulley Separator ... 

Ball charge equal to 35-50 percent of the mill volume gives the maximum capacity. 

The energy requirement for reducing MSW to 90 percent passing 10 cm is typically 6 kWh/ton, or 50 kWh/ton for passing 1 cm. Wear is also a major cost, and wear rates are shown in Fig. 20-60. The maximum capacity of commercially available hammer mills is about 100 ton/h. 

Sources Subject to Prevention of Significant Deterioration (PSD) Sources subject to PSD regulations (40 CFR, Sec. 52.21, Aug. 7, 1980) are major stationary sources and major modifications located in attainment areas and unclassified areas. A major stationaiy source was defined as any source hsted in Table 25-4 with the potential to emit 100 tons per year or more of any pollutant regulated under the Clean Air Act (CAA) or any other source with the potential to emit 250 tons per year or more of any CAA pollutant. The potential to emit is defined as the maximum capacity to emit the pollutant under apphcable emission standards and permit conditions (after apphcation of any air pollution control equipment) excluding secondaiy emissions. A major modification is defined as any physical or operational change of a major stationaiy source producing a significant net emissions increase of any CAA pollutant (see Table 25-5). 

A 125 h.p. motor may still suffice, which the manufacturer alone can confirm, knowing the maximum capacity of a 125 h.p. frame. 

Depending on the operating conditions, the first few stages are of 50% reaction to obtain maximum capacity for the selected speed. In the downstream stages, where Mach numbers are lower due to the higher gas temperatures, 80% reaction blading is used to reduce the... 

Equation (33) shows that the maximum capacity ratio of the last eluted solute is inversely proportional to the detector sensitivity or minimum detectable concentration. Consequently, it is the detector sensitivity that determines the maximum peak capacity attainable from the column. Using equation (33), the peak capacity was calculated for three different detector sensitivities for a column having an efficiency of 10,000 theoretical plates, a dead volume of 6.7 ml and a sample concentration of l%v/v. The results are shown in Table 1, and it is seen that the limiting peak capacity is fairly large. 

Design Example for a Batch Nutsche Filter Operation A batch Nutsche filter operates under constant pressure and maximum capacity with three stages filtration, washing and drying. The Nutsche filter with a 1 m filtration area operates under the following set of conditions ... 

To apply these equations, let s consider the following example. Determine a constant rate of filtration and the time of operation corresponding to the maximum capacity of a batch filter having the following conditions maximum permissible pressure difference AP = 9x10 N/m sludge viscosity /r = 10 N-s/m filter plate resistance Rf = 56x 10 ° m specific cake resistance r = 3 X 10 m ° x = 0.333 auxiliary time = 600 s maximum permissible cake thickness h = 0.025 m. The solution is as follows ... 

The salt consumption with a sodium 0.275 and 0.533 Lbs of salt per 1,000 grains of hardness, expressed as calcium carbonate, removed. This range is attributed to two factors (1) the water composition, and (2) the operating exchange value at which the exchange resin is to be worked. The lower salt consumption may be attained with waters that are not excessively hard nor high in sodium salts, and where the exchange resin is not worked at its maximum capacity. 

The vapor to be relieved is the vapor that is in equilibrium with the liquid under conditions existing when the valve is relieving at maximum capacity. It should not be overlooked that the vapor and liquid composition may change as... 

Other types of pressure-relief valves do not depend upon the back pressure for their performances. However, to ensure that the safety valves work at their maximum capacity, back pressure is limited to 50 percent of the relief valve set pressure. In the balanced bellows type valve, the spring does not act directly on the disk. Instead, it serves on a bellows first, which in turn acts on the disk. In case of the piston type, it works on the same principle as the bellows type, except that the bellows is replaced by a piston (see Figure 17B). The cross-sectional area of both the piston and the bellows is the same as the inlet nozzle of the valve and the effect of the back pressure on the top and the bottom of the disk creates equal balancing forces. That is, P,A is always equal to F, as shown in Figure 17B. 

Limit the total possible charge to a batch reactor by using a precharge or feed tank of limited capacity. Alternatively, limit the addition rate by selecting a pump with a maximum capacity lower than the safe maximum addition rate for the process, or by using restriction orifices. 

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