The correct answer is D. All the above.
An Imhoff tank is a type of sewage treatment tank that consists of two main parts: a sedimentation tank and a digestion tank. The sedimentation tank is where the solid waste settles to the bottom of the tank, while the digestion tank is where the solid waste is broken down by anaerobic bacteria.
The shape of an Imhoff tank is rectangular. This shape allows for the most efficient sedimentation and digestion of the solid waste. The detention period of an Imhoff tank is 2 hours. This means that the solid waste stays in the tank for 2 hours before it is discharged. The velocity of flow in an Imhoff tank is restricted to 0.30 m/minute. This helps to ensure that the solid waste has enough time to settle and digest.
Imhoff tanks are a very effective type of sewage treatment tank. They are used in many parts of the world to treat sewage from homes, businesses, and industries.
Here are some additional details about each of the options:
- Option A: The shape of an Imhoff tank is rectangular. This shape allows for the most efficient sedimentation and digestion of the solid waste. The solid waste settles to the bottom of the tank, while the lighter material floats to the top. The solid waste is then broken down by anaerobic bacteria in the digestion tank.
- Option B: The detention period of an Imhoff tank is 2 hours. This means that the solid waste stays in the tank for 2 hours before it is discharged. This allows enough time for the solid waste to settle and digest.
- Option C: The velocity of flow in an Imhoff tank is restricted to 0.30 m/minute. This helps to ensure that the solid waste has enough time to settle and digest. If the velocity of flow is too high, the solid waste will not have enough time to settle and will be discharged before it has been properly treated.
I hope this information is helpful. Please let me know if you have any other questions.