written 19 months ago by
Chandan15
• 300

•
modified 19 months ago

The concentrations of $\mathrm{NO} x, \mathrm{HC}, \mathrm{CO}$ and others are generally very much less than the concentration of $\mathrm{SO}_{2}$ in various industries. Hence the Board has made only $\mathrm{SO}_{2}$ as the criterion for design, along with the particulate matter.
(a) Height of chimney on the basis of particulate matter.
$$
h=74\left(Q_{p}\right)^{0.27}
$$
Particulate matter emission $=4(1.5 \times 12)=72 \mathrm{t} /$ year
Assuming 300 working days in a year, and 24 hours working a day.
$$
\begin{aligned}
Q_{p} &=\frac{72}{300 \times 24}=0.01 \mathrm{t} / \mathrm{hour} \\
h &=74(0.1)^{0.27}=21.34 \mathrm{~m}
\end{aligned}
$$
(b) Height of chimney on the basis of $\mathrm{SO}_{2}$
Now,
$$
\mathrm{SO}_{2} \text { emission }=20(1.5 \times 12)=360 \mathrm{t} / \text { year }
$$
$\therefore$
$$
\begin{aligned}
Q &=\frac{360}{300 \times 24}=0.05 \mathrm{t} / \text { year }=50 \mathrm{~kg} / \mathrm{hr} \\
h &=14(50)^{1 / 3}=51.58 \mathrm{~m}
\end{aligned}
$$
$$
\therefore \quad h=14(50)^{1 / 3}=51.58 \mathrm{~m}
$$
$\therefore$ Required height of chimney $=52 \mathrm{~m}$ (maximum of $21.34 \mathrm{~m}$ and $51.58 \mathrm{~m}$ )