Respuesta :
Answer:
Weight Percentage of Ash = 3.4
Explanation:
Given - Coal containing 21% ash is completely combusted, and the ash is 100% removed in a water contact scrubber. If 10,000 kg of coal is burned per hour with a scrubber flow rate of 1.0 m3/min.
To find - the weight percentage of the ash in the water/ash stream leaving the scrubber is most nearly ?
Solution -
Given that,
Coal Burned Rate = 10,000 kg/hr
               = [tex]\frac{10,000}{60 min} * 1 hr *\frac{kg}{hr}[/tex]
               = 166.6666 kg/min
⇒Coal Burned Rate = 166.6666 kg/min
Now,
Given that,
Ash content in coal = 21 %
⇒Ash in (coal that burned) = 166.6666 × [tex]\frac{21}{100}[/tex] kg/min
                       = 34.9999 ≈ 35 kg/min
⇒Ash in (coal that burned) = 35 kg/min
Now,
We know,
Density of water = 1000 kg/m³
Now,
Water flow Rate = [tex]1\frac{m^{3} }{min} * density[/tex]
              = 1000 kg/min
⇒Water flow Rate = 1000 kg/min
Now,
Total Mass flow Rate of (Water + Ash stream) = ( 1000 + 35) kg/min
                                      = 1035 kg/min
⇒Total Mass flow Rate of (Water + Ash stream) = 1035 kg/min
So,
Weight Percentage of Ash = (Weight of Ash ÷ Total weight of Stream) × 100
                      = (35 ÷ 1035) × 100
                      = 3.38 ≈ 3.4
∴ we get
Weight Percentage of Ash = 3.4