Answer Happy

1. Compute for the boiler efficiency using the Indirect Method,
and Direct Method.
An industrial Steam Plant generates 20 Tph (steady – all year The
measured fuel flow rate is 30 m³/min and the cost
of fuel oil is (P 60/m³).
• The HHV of the natural gas is 54,220 kJ/kg (40,144 kJ/m³).
• Superheated steam is generated at 20 bars, 385°C and boiler
feedwater from the deaerator is at 25 bars, 120°C.
• Shell loss is 0.4%
• Conductivity for blowdown = 2,000 mhos/cm
• Conductivity for feedwater = 100 mhos/cm
• Makeup water temperature: 20°C
• Hblowdown = 970 kJ/kg
• Stack Loss = 14%
• Flue gas oxygen: 5%
For enthalpy, use
https://www.steamtablesonline.com/Steam97Web.aspx
2. Compute the cost associated in steam production, and the cost
due the loses.
Guide Figure for the Problem.
Combustion Gases Combustion Air Preheater Distribution Economizer Combustion Air Isolation Valve Forced Draft Fan Boiler Fuel Feed Pump Generation End Use Shell and Tube Heat Exchanger Steam Trap Deaerator Pressure Reducing Valve ||||| Process Heater Steam Trap Recovery Process Heater Steam Trap Condensate Pump Condensate Receiver Tank