Question

1. Coal gasification consists of the chemical transformation of solid coal into gas. The heating values of coal differ, but the higher the heating value, the higher the value of the gas produced (which is essentially methane, carbon monoxide, hydrogen, etc.). The following coal has a reported heating value of 29,770 KJ/Kg as received. Assuming that this is the gross heating value, calculate the net heating value.

Answer 1

Complete question:

Coal gasification consists of the chemical transformation of solid coal into gas. The heating values of coal differ, but the higher the heating value, the higher the value of the gas produced (which is essentially methane, carbon monoxide, hydrogen, etc.). The following coal has a reported heating value of 29,770 KJ/Kg as received. Assuming that this is the gross heating value, calculate the net heating value.. Component__________Percent  C___________________71

H2__________________5.6

N2__________________1.6

S____________________2.7

Ash__________________6.1

O2___________________13

Answer:

LHV = 28478.8 KJ/kg

Explanation:

The gross heating value is also the higher heating value (HHV), while the net heating value is the lower heating value (LHV).

This involves the conversion from higher heating value (HHV) to lower heating value(LHV).

Let's use the formula:

LHV = HHV - 0.212H - 0.0245M - 0.008A

We are given

HHV = 29,770 KJ/kg = 29.770MJ/kg

H = hydrogen% =5.6%

A = oxygen% = 13%

M = 0

Substituting the figures in the formula, we have:

LHV = 29.770 - 0.212*5.6 - 0.0245*0 - 0.008*13

= 29.770 - 1.1872 - 0 - 0.104

= 28.4788 MJ/kg

= 28478.8 KJ/kg

LHV = 28478.8 KJ/kg

The net heating value, LHV = 28478.8 KJ/kg