Grit Removal Practice Questions for Level 1 · Entry

1. Question 1

   What does a **grit chamber** mainly remove from wastewater?

   1. Rags and plastics caught on screen bars
   2. Oil and grease floating on the surface
   3. Dissolved compounds carried in the flow
   4. Sand, gravel, and other heavy particles
   Show the answer

   Answer: D. Sand, gravel, and other heavy particles

   A grit chamber removes relatively heavy particles such as sand, gravel, cinders, and similar material while allowing lighter organic material to continue with the wastewater.

2. Question 2

   What is the main purpose of a grit chamber?

   1. To disinfect treated effluent
   2. To add oxygen to wastewater
   3. To remove sand and small stones
   4. To settle biological solids
   Show the answer

   Answer: C. To remove sand and small stones

   A grit chamber removes heavy inorganic material such as sand, grit, cinders, and small stones before it can wear or clog downstream equipment.

3. Question 3

   Washed grit has a strong septic odor and visible organic matter. Influent conditions are normal. What should the operator check first?

   1. Check grit-wash flow
   2. Speed the primary skimmer
   3. Raise return-sludge flow
   4. Lower chlorine feed rate
   Show the answer

   Answer: A. Check grit-wash flow

   Low or interrupted grit-wash flow can leave organics with the grit. Return sludge, chlorine feed, and the primary skimmer do not control washing in the grit classifier.

4. Question 4

   Collected grit is black and foul-smelling. The wash system meets its target, but the hopper discharge interval has increased from 4 hr to 16 hr. What should the operator do?

   1. Resume 4 hr discharge
   2. Reduce wash-water flow
   3. Lower classifier speed
   4. Stop the chamber aeration
   Show the answer

   Answer: A. Resume 4 hr discharge

   Returning to the 4 hr discharge interval reduces the 16 hr storage period that allows organics in collected grit to turn septic. Reducing wash water, slowing the classifier, or stopping chamber aeration can reduce grit-system performance.

Operator Master has 4 Level 1 · Entry grit removal questions, free.

• Plant Operations54 questions
• Math and Calculations50 questions
• Laboratory13 questions
• Safety13 questions
• Biological Treatment12 questions
• Disinfection10 questions
• Pumps and Hydraulics8 questions
• Regulations and Compliance8 questions
• Solids Handling8 questions
• Primary Treatment6 questions
• Secondary Clarification5 questions
• Headworks and Screening4 questions