Consider the following statements regarding waste stabilization ponds: 1. The pond has a symbiotic process of waste stabilization through algae on one hand and bacteria on the other 2. The oxygen in the pond is provided by algae through photosynthesis 3. The detention period is of the order of two to three days 4. The bacteria which develop in the pond are aerobic Which of the above statements are correct?

1 and 2 only
2 and 3 only
3 and 4 only
1 and 4 only

LohaHridoy

4 views

2025-01-04 04:42

1 Answers

AhmedNazir

Option 1 : 1 and 2 only

Explanation:

Wastewater stabilization ponds
Definition	This is a large man-made water body in which wastewater is treated by using a naturally occurring process such as micro-organisms, and algae.
Functions	B.O.D removal of wastewater. Dissolve organic material in water Breakdown biodegradable organic material
working	They are built up to a depth of 1 to 1.5 m. Photosynthetic algae produce oxygen in the water and consume the carbon dioxide produced by bacteria, thus algae and bacteria carry on the symbiotic process of waste stabilization. The bacteria which develops in the pond is anaerobic. The detention time is 10 to 20 days.

4 views Answered 2022-09-04 04:29

Related Questions

Consider the following statements regarding activated sludge process: 1. Industries prefer activated sludge process as it requires less space, does not produce obnoxious odours and requires less time for waste water treatment compared to trickling filter. 2. It requires skilled supervision 3. Biological treatment is enhanced because shock loadings are eliminated. Which of the above statements are correct?

1 Answers 4 Views

Consider the following relation on subsets of the set of integers between 1 and 2014. For two distinct subsets U and V of S we say U < V if the minimum element in the symmetric difference of the two sets is in U. Consider the following two statements: S1: There is a subset of S that is larger than every other subset. S2: There is a subset of S that is smaller than every other subset. Which one of the following is CORRECT?

1 Answers 4 Views

Consider the following statements- 1. The smallest unit of the Early Vedic period was kula and Jana was the highest unit. 2. The king's position of the Early Vedic period was hereditary and the king could exercise unlimited power as he was not answerable to anyone. 3. The position of women in the early Vedic period was miserable and child marriage was prominent. 4. Women were allowed to attend Sabha and Vidhata assemblies in the Early Vedic Period. Which of the above statements is/are correct?

1 Answers 4 Views

In the following question, the 1st and the last part of the sentence/passage are numbered 1 and 6. The rest of the sentence/ passage is split into four parts and named P, Q, R and S. These four parts are not given in their proper order. Read the sentence/passage and find out which of the four combinations is correct. S1. The mineral wealth of the country, the coal, iron, oil, gas, and the like, does not reproduce itself. P. Wastefulness in dealing with it today means that our descendants will feel the exhaustion a generation or two before they otherwise would. Q. Therefore it is certain to be exhausted ultimately. R. But there are certain other forms of waste which could be entirely stopped. S. The waste of soil by washing, for instance, which is among the most dangerous of all wastes now in progress in the United States, is easily preventable. S6. The preservation or replacement of the forests is one of the most important means of preventing this loss. ?

1 Answers 5 Views

Consider the following statements in respect of aerated grit chamber: 1. The grit accumulates at the bottom in advancing spiral-flow aeration tanks location ally preceded by grit chambers, led to the eventual development of aerate grit chambers. 2. The excessive wear on grit handling equipment is a major factor for the popularity of aerated grit chambers. 3. Aerated grit chambers are designed to provide detention period of 1 minute at maximum rate of flow. 4. Diffusers are located at 0.45 m to 0.6 m above the bottom of the chamber. Which of the above statements are correct?

1 Answers 4 Views

Consider the given statement to be true even if it seems to be at variance with the commonly known facts and decide which of the given conclusion logically follow(s) from the statement. Statement: Waste management is one of our country’s most important concerns these days given the fast pace of growing population and increasing wastes. Conclusions: I. Waste management was not a major concern of our country earlier. II. Apart from waste management, our country might also havee other major concerns these days.?

1 Answers 4 Views

Consider the following statements regarding pyrolysis: 1. It is an irreversible chemical change brought about by the action of heat in oxygen-free atmosphere. 2. Range of temperature is 500°C to 1000°C. 3. Internal heating causes organic matter to decompose physically and chemically rather than burn. 4. It is a highly exothermic process. Which of the above statements are correct?

1 Answers 4 Views

Consider the following statements regarding contact stabilization process: 1. Primary settling tank is not required in some cases. 2. BOD removal occurs in two stages. 3. Aeration volume requirements are approximately 50% of those of a conventional – or tapered – aeration plant. 4. Returned sludge is aerated for 30 min to 90 min in sludge aeration tank. Which of the above statements are correct?

1 Answers 5 Views

Consider the following statements: 1. Both Otto and Diesel cycles are special cases of dual combustion cycle 2. Combustion process in IC engines is neither fully constant volume nor fully constant pressure process 3. Combustion process in ideal cycle is replaced by heat addition from internal source in closed cycle 4. Exhaust process is replaced by heat rejection in ideal cycle Which of the above statements are correct?

1 Answers 4 Views

Consider the following statements about process state transitions for a system using preemptive scheduling. I. A running process can move to ready state. II. A ready process can move to running state. III. A blocked process can move to running state. IV. A blocked process can move to ready state. Which of the above statements are TRUE?

1 Answers 4 Views

এক্সাম দিয়ে মেধা যাচাই করুন

Job Preparation (1125)

Admission (754)

এসএসসি (10)

এইচএসসি (5)