Option (c) is correct. Parshall flumes are proportioning weirs and they maintain constant flow velocity  in grift chamber for settling (Type-I) of inorganic particles.

Parshall Flume in Sewage Treatment Units

A Parshall flume is a type of flow measuring device used in wastewater treatment plants to measure the flow rate of liquid. It is a flume with a particular shape that allows for accurate measurement of flow rate by utilizing the principle of continuity of mass and energy.

Grit Chamber

A grit chamber is a component of a wastewater treatment plant that is designed to remove heavy materials such as sand, gravel, and other heavy solids from the wastewater. The grit chamber is typically the first stage of the treatment process, and it is designed to protect downstream equipment and processes from damage caused by these heavy materials.

Parshall Flume in Grit Chamber

The Parshall flume is often used in grit chambers to measure the flow rate of wastewater as it passes through the chamber. The flume is installed at the inlet of the chamber, where the wastewater enters. The flow rate is then measured by observing the water level in the flume and using a conversion chart to determine the actual flow rate.

Advantages of Parshall Flume

The Parshall flume is an accurate and reliable flow measuring device that is widely used in wastewater treatment plants. It is preferred over other flow measuring devices because of its many advantages:

1. Accuracy: The Parshall flume is highly accurate and can measure flow rates with great precision.

2. Easy to Install: The flume is easy to install and requires minimal maintenance.

3. Versatile: The flume can be used in a wide range of applications, making it a versatile choice for wastewater treatment plants.

4. Low Cost: The Parshall flume is a cost-effective solution for measuring flow rates in wastewater treatment plants.

Conclusion

In conclusion, the correct answer to the question is C) Grit Chamber. The Parshall flume is often used in grit chambers to measure the flow rate of wastewater as it enters the chamber. The flume is an accurate and reliable flow measuring device that is widely used in wastewater treatment plants.