Solid waste management: Composting and land fill related mcq question discussion

Composting and land fill related questions discussion

1. Sanitary Chemist Topic: Solid Waste Management- Composting

2. Question 1

3. Explanation

4. Question 2

5. Explanation

6. Question 3

7. Explanation

8. Question 4

9. Explanation

10. Question 5

11. Explanation

12. Question 6

13. Explanation

14. Question 7

15. Explanation

16. Question 8

17. Explanation Field composting and windrow composting is a type of non-reactor system of classification of the composting systems. Field composting doesn’t use thermal disinfection method as it lacks self-heating mechanism due to its exposure to a larger surface area and the waste having sanitation problem cannot be used for composting in this method Field composting is the simplest way of microbial composting which takes place in a very thin layer above the soil surface. Horizontal reactor, vertical reactor are major types of reactor system for microbial composting. In vertical reactor, the waste flows vertically with mass flow in a vertical direction. Waste is loaded into a horizontal reactor composting system with a wheel loader.

18. Question 9

19. Explanation Vermicomposting uses earthworms for composting by degrading the organic wastes present in the bulk waste material by various methods. The major objective is to obtain products free of any pollutants and hence, toxic products are eliminated in the process, and the other two objectives of Vermicomposting are to elevate the value of original material and to accelerate the rate of degradation.

20. Question 10

21. Explanation Low growth rate is not seen in earthworms selected for Vermicomposting as they have a high growth rate. The digestion rate and absorption rate of the consumed food by earthworms is high. They can very well adapt to the changing environmental conditions, that makes them more suitable for Vermicomposting .

22. Question 11

23. Explanation Plasmodium  species is a malaria parasite and is not a species of earthworms. Epifilis , Endogens, Aneciques  are the most common species of earthworms used as Vermicomposting earthworms, some with dark pigments and some with uniform coloration having high growth rate, the digestion rate and absorption rate of the consumed food by earthworms is high and they can very well adapt to the changing environmental conditions.

24. Question 12

25. Explanation The major environmental concern related to landfill is the discharge of leachates into the immediate environment which pose a great threat to the environment, so, the major concern is to control it, whereas, limited space, technology and man-power do not pose environmental threat.

26. Question 13

27. Explanation Biodegradable are substances capable of being broken down by living organisms such as bacteria and other microorganisms . Examples include- Food Products, Paper, Organic Waste, Cow dung, Paper, etc. Humans manufacture many products that get wasted and thrown away, causing a lot of harm to the environment. The living organism breaks down the ‘biodegradable’ wastes through biological processes.  A few examples of Biodegradable wastes are: Papers, Human waste , Sewage sludge, Dead animals and plants, Hospital waste , Food waste, Manure, Starch-based plastics, Natural fibers reinforce plastic , Slaughterhouse waste etc.

28. Question 14

29. Explanation Land filling is a process of disposal of solid waste under the soil. It is usually done in low lying areas to prevent unhygienic conditions.

30. Question 15

31. Explanation Land fill gases are produced during the dumping of waste. They are foul smell creating unhygienic conditions.

32. Question 16

33. Explanation

34. Question 17

35. Explanation

36. Question 18

37. Explanation Food waste can be decomposed by bacteria as they are biodegradable waste. A shes and glass are non biodegradable Microbes can easily decompose organic matter like vegetable and fruit peels, animal and plant waste, dead leaves, plants, and animals. Plastics generally cannot be decomposed by microbes.

38. Question 19

39. Explanation Organic waste is formed into rows of long piles called “windrows” and aerated by turning the pile periodically by either manual or mechanical means. The ideal pile height, which is between 4 and 8 feet, allows for a pile large enough to generate sufficient heat and maintain temperatures, yet small enough to allow oxygen to flow to the windrow's core. The ideal pile width is between 14 and 16 feet.

40. Question 20

41. Explanation Compost is a mixture of organic residues (manure, animal carcasses, straw, etc.) that have been piled, mixed and moistened to undergo thermophilic decomposition  Leaves are perhaps the best material because of their availability and organic content; however, other types of organic materials such as  animal manures, grass clippings, vegetable refuse, small tree limbs and shrub trimmings, coffee grounds, and rotted sawdust are considered good composting materials.

42. Question 21

43. Explanation

44. Explanation Worms will eat a wide variety of organic materials such as  paper, manure, fruit and vegetable waste, grains, coffee grounds, kitchen waste, plant materials, and ground yard wastes . As the organic matter passes through the gizzard of the earthworm it is grounded into a fine powder after which the digestive enzymes, microorganisms and other fermenting substances act on them further aiding their breakdown within the gut, and finally passes out in the form of “ casts”which are later acted upon by earthworm gut associated microbes converting them into mature product, the “ vermicomposts ”.

45. Question 22

46. Explanation Eisenia fetida , commonly known as the red wigglers or red earthworms, are widely considered to be the best species for vermicomposting because of several key reasons:  Optimal temperature and moisture conditions : Red wigglers are well adapted to the warm, moist conditions that are ideal for vermicomposting. Redworms ( Lubricous rubellus ), Perionyx excavatus (Indian blueworm ) and Eudrilus eugeniae (African night crawler) can also be used effectively.

47. Question 23

48. Explanation The worm castings are very important to the fertility of the soil. The castings contain high amounts of nitrogen, potassium, phosphorus, calcium, and magnesium. In addition to micronutrients, advantageous soil bacteria, and hormones involved in plant growth & enzymes, vermicompost is a rich source of NKP (nitrogen 2-3%, potassium 1.85-2.25%, and phosphorus 1.55-2.25%).

49. Question 24

50. Explanation

51. Question 25

52. Explanation

53. Thank You