Advertisements
Advertisements
Question
Explain how sludge is treated.
Advertisements
Solution
- In the clarifier (or sedimentation tank), sludge settles at the bottom and is collected using a scraper. It is then moved to a separate tank known as the digester, where it is digested by anaerobic microorganisms.
- The biogas created during the process can be utilized for fuel or to generate electricity. The clarified water from the sedimentation tank is pumped into the aeration tank. In the aeration tank, suspended microorganisms sink to the bottom as activated sludge.
- The activated sludge is approximately 97% water. Water is removed using sand-drying beds or machinery. Dried sludge is utilized as manure, reintroducing organic matter and nutrients into the soil.
APPEARS IN
RELATED QUESTIONS
Dried ______ is used as manure.
Drains get blocked by ______ and ______.
Describe the steps involved in getting clarified water from wastewater.
Name two chemicals used to disinfect water.
Explain the function of bar screens in a wastewater treatment plant.
Study the following statements about ozone:
- It is essential for breathing of living organisms.
- It is used to disinfect water.
- It absorbs ultraviolet rays.
- Its proportion in air is about 3%.
Which of these statements are correct?
Which of the following is/are products of wastewater treatment?
State whether the following statement is True or False. In case a statement is false, write the correct statement.
Sewage is a solid waste which causes water pollution and soil pollution
Given below is a jumbled sequence of the processes involved in a wastewater treatment plant. Arrange them in their correct sequence.
- Sludge is scraped out and skimmer removes the floating grease.
- Water is made to settle in a large tank with a slope in the middle.
- Large objects like plastic bags are removed by passing wastewater through bar screens.
- Sand, grit and pebbles are made to settle by decreasing the speed of incoming wastewater.
- Wastewater enters a grit and sand removal tank.
What is sludge?
