If [$_env$ < [$_d$ ,where [$_env$ and [$_d$ are environmental & dry adiabatic lapse rates respectively ,which of the following types of plume emitted from a stack of a thermal power plant is observed ?
Stack Emission Plume Behavior Explained
The question relates the environmental lapse rate ($\gamma_{env}$) to the dry adiabatic lapse rate ($\gamma_d$) to determine the type of plume observed from a stack. The condition given is $\gamma_{env} \lt \gamma_d$.
Atmospheric Stability Analysis
Atmospheric stability determines how pollutants disperse vertically. The relationship between the environmental lapse rate and the dry adiabatic lapse rate indicates stability:
- Unstable: $\gamma_{env} \gt \gamma_d$ (Strong vertical mixing)
- Neutral: $\gamma_{env} = \gamma_d$ (Moderate vertical mixing)
- Stable: $\gamma_{env} \lt \gamma_d$ (Weak vertical mixing)
The condition $\gamma_{env} \lt \gamma_d$ signifies a stable atmosphere. In such conditions, vertical movement is suppressed because the surrounding air is relatively buoyant compared to the rising plume parcels, or resists downward movement.
Plume Type Identification
In a stable atmosphere, vertical dispersion is limited. Pollutants emitted from the stack spread primarily in the horizontal direction, following the wind. This results in a plume that is narrow vertically and elongated horizontally, resembling a fan.
Therefore, when $\gamma_{env} \lt \gamma_d$, the observed plume type is Fanning.
Important Questions from Air and Noise Pollution - Teaching
Statement (I): The impact of Green House Gas emissions on the environment may comprise an accelerated increase in global warming as well as a significant rise in mean sea levels.
Statement (II) : Green House Gas omission is responsible for decreased landmasses, increased population densities, and food shortages.
Choose the correct statement from the following:
The equivalent noise level is significant for the following:
- Electrostatic Precipitator is used in Thermal Power Plants to remove which of the following air pollutants?
- What is Noise Induced Permanent Threshold Shifts (NIPTS) ?
- The photodissociation of $NO_{2}$ yields which oxygen species ?
