$($b$)$ The plat uses a $10$ TPH boiler to produce steam at a gauge pressure of $12k\frac{g}{c}{m}^2$ and uses the above grade of coal. The enthal py of the enthalpy of saturated steam is $680$kCa$\frac{l}{k}g$ at $10k\frac{g}{c}{m}^2$ pressure and the feed water enthalpy is $100$kCa$\frac{l}{k}g$ at $80C.$ The coal consumption rate is $4$ TPH$.($use the conversion: $1J-0\mathrm{.}239$Cal $).$ Evaluate the boiler efficiency using the Direct Method.

$[4]$

$($c$)$ Evaluate the loss due to dry flue gas if the mass of dry flue gas $(C_p=0\mathrm{.}23kCalk{g}^{2}C)$ is $6k\frac{g}{k}g$ of fuel and the average flue gas temperature and ambient temperature are $200C$ and $30C$ respectively.

$($d$)$ Also evaluate the heat loss due to moisture present in the fuel if the weight ratio of moisture in the fuel is $0\mathrm{.}3k\frac{g}{k}g$ of fuel.

$[2]$

$($c$)$ As an energy manager, cast your opinion on a suitable waste beat recovery device recuperator or regenerator$)$ for the above plant. Give proper justification for your suggestions.

$[3]$