Equipment sizing turbines

Once the highest steam level is set, then intermediate levels must be established. This involves having certain turbines exhaust at intermediate pressures required of lower pressure steam users. These decisions and balances should be done by in-house or contractor personnel having extensive utility experience. People experienced in this work can perform the balances more expeditiously than people with primarily process experience. Utility specialists are experienced in working with boiler manufacturers on the one hand and turbine manufacturers on the other. They have the contacts as well as knowledge of standard procedures and equipment size plateaus to provide commercially workable and optimum systems. At least one company uses a linear program as an aid in steam system optimization. 

Judat s [53] comparative evaluation of nine publications concerning mass transfer in the air/water system in vessels equipped with turbine stirrers has already been mentioned. The vessel sizes covered liquid volumes from V = 2.5 liters to 906 m3 (p= 1 71). This evaluation unambiguously proved that the process equation is presented in the following pi-space... 

Interest is increasing in running units at elevated pressures (6-15 atm) in order to reduce equipment size, lower emissions, reduce sorbent requirements, and increase the thermal efficiency by using a gas turbine in addition to a steam turbine in a combined cycle. There is also a trend away from bubbling beds and toward circulating beds, which use finer solids and higher velocities and are able to use sorbents more efficiently. 

Close-Coupled Pumps (Fig. 10-38) Pumps equipped with a built-in electric motor or sometimes steam-turbine-driven (i.e., with pump impeller and driver on the same shaft) are known as close-coupled pumps. Such units are extremely compact and are suitable for a variety of services for which standard iron and bronze materials are satisfactory. They are available in capacities up to about 450 mVh (2000 gal/min) for heads up to about 73 m (240 ft). Two-stage units in the smaller sizes are available for heads to around 150 m (500 ft). 

After the type of driven equipment is selected, the horsepower require ments must be estimated. Unless the horsepower requirements happen to fit one of the gas turbine sizes available, a gas engine will be needed. 

Rotary vertical shaft turbine units as shown in Figure 10 and other rotary or reciprocating equipment are other examples. Tapered flocculation may be obtained by varying reel or paddle size on horizontal common shaft units or by varying speed on units with separate shafts and drives. In applications other than coagulation with alum or iron salts, flocculation parameters may be quite different. Lime precipitates are granular and benefit little from prolonged flocculation. 

For locations in the Middle East subject to wide fluctuations in ambient temperature it has been common to utilize multiple gas turbines which are sized to meet the plant demands during the hot summer months and the cold winter. As the gas turbine output increases substantially, there is sufficient spare capacity to allow for outage of machines without affecting the electrical power export. However, this situation is unique to the environmental conditions and type of equipment in service. 

In addition to the larger and larger turbines under development, residential customers can also invest in small turbines of about 24-feet in diameter that stand on towers from 35 to 140 feet high. These systems have the potential to save users between 30% and 90% on their electric bills. Prices for the systems (including installation) run between 8,500 and 80,000, depending on the size and capacity of the equipment. 

As noted before, in order to replace conventional power components with hydrogen technologies in renewable energy-based autonomous power systems, an oveidimensioning of RE equipment is usually necessary. Nevertheless, the results of Fair Isle s wind-hydrogen system optimisation revealed that there is no need for additional wind turbines on the island, due to the fact that in the existing wind-diesel power system the wind turbines were already oversized. More specifically, the first preliminary runs conducted with HOMER software demonstrated that the size of the wind turbines to be considered in the analysis will also be 100 kW and 60 kW, respectively. 

Determine the reactor volume required for one reactor and that for two equal-sized reactors in series for 80 percent conversion of A. And if the capital cost of a continuous-flow stirred-tank reactor unit is given by 200,000(17/100)° 6 (where V is reactor volume in m3), the life is 20 years with no salvage value, and power costs 3 cents per kilowatt-hour, determine which system has the economic advantage. Assume that overhead, personnel, and other operating costs, except agitation, are constant. The operating year is 340 days. Each reactor is baffled (with a baffle width to tank diameter of 1/12) and equipped with an impeller whose diameter is one-third the tank diameter. The impeller is a six-bladed turbine having a width-to-diameter ratio of 1 /5. The impeller is located at one-third the liquid depth from the bottom. The tank liquid-depth-to-diameter ratio is unity. 

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