# Homework Help: Finding Fuel Consumption

1. Nov 29, 2015

### 0drt9

• Member warned about posting with no effort shown
1. The problem statement, all variables and given/known data
A boiler is to produce 6250 kg/h of steam superheated by 40 oC at a pressure of 2.1 MN/m2. The temperature of the feedwater is 50 oC. If the thermal efficiency of the boiler is 70%, how much fuel oil will be consumed in one hour? The calorific value of the fuel oil used is 45000 kJ/kg, cp of superheated steam is 2.093 kJ/kg K.
for pressure 2.1 Mn/m2
hfg = 1880 kJ/kg
hf = 920 kj/KG
sat temp - 214.9

2. Relevant equations
in my notes i have efficiency as [generated steam * hfg] / [fuel consumed * CV ]

3. The attempt at a solution
my attempt gave me the answer of 373 which i found to be to small of a value

2. Nov 29, 2015

### Staff: Mentor

3. Nov 29, 2015

### 0drt9

i used efficiency = [generated steam * hfg] / [fuel consumed * CV ]
for efficiency i used 0.70, for generated steam 6250, hfg 1880, CV as 45000
and i found for the fuel consumed

4. Nov 29, 2015

### SteamKing

Staff Emeritus