Transcript Document
Example
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Expansion and compression are isentropic.
Find
Thermal efficiency
For a net power output of 330MW, find the
steam flow rate through the first turbine stage
(kg/hr)
Cogeneration
• Utilization factor
* U = (net work + process heat)/(total heat
input)
Combined cycle
• th = (powergas + powervapor)/(total heat input)
Industrial Processes
Energy forms
• Electricity
• Direct-fired
• Steam
Steam system
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High heat capacity
Ease of transport
Low cost vs alternatives
Non-toxic
Steam system usage
2006: percent of energy used from steam
• Petroleum refining: 28%
• Chemical manufacture: 47%
• Forest products: 76%
Paper manufacture
Fiber board
Plywood
Generation
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Boiler
Fuel supply
Combustion air system
Feed water supply system
Exhaust gas system
Distribution
• Pressure & flow regulation
• Thermal insulation
• Traps
End Use
• Heat exchangers – transfer energy
• Turbines – convert thermal energy to
mechanical energy
Recovery
• Condensate
S.D. Warren
• Condensers: power & recovery boilers
• Dryers: product water removal and moisture
control
• Evaporators: increase solids of black liquor for
fuel
• Steam ejector: vacuum for condenser & low
pressure steam recovery
• Steam injector: process chemical heating
U.S. Department of Energy
• Improving Steam System Performance
• Combined Heat and Power: A Clean Energy
Solution