In an energy audit the following information was obtained fr

In an energy audit, the following information was obtained from the inspection of a boiler: Assume 5% loss due to surface losses and blow-down. Rate of steam production Boiler efficiency If the boiler is tuned so that so that no unburnt material is detected and O2 level in the exhaust is reduced to 3%, how much improvement in efficiency is expected? The exhaust temperature remains the same as before. What is the maximum flame temperature that can be expected in the boiler? You may use an online calculator for this purpose.

Solution

1.Rate of steam production per hr = HP*34.5

Now 30MBTU/hr = 896.18 HP

So steam production rate Q = 896.18*34.5 = 30918.2 lb/hr

2.Boiler efficiency = (Q*(H-h))/(q*GCV)*100

Where Q = Quantity of steam generated per hour (kg/hr) q = Quantity of fuel used per hour (kg/hr) GCV = Gross calorific value of the fuel (kCal/kg) H = Enthalpy of steam (kCal/kg) h = Enthalpy of feed water (kCal/kg)