Environmental Engineering
Sources and Coveyances Water
Marks 1Marks 2
Quality Control of Water
Marks 1Marks 2
Treatment of Water
Marks 1Marks 2
Water Demand
Marks 1Marks 2
Waste Water Characteristics
Marks 1Marks 2
Sewage System and Sewer Appurtenances
Marks 1
Treatment of Sewage
Marks 2
Disposal of Sewage Effluent
Marks 1Marks 2
Solid Waste Management
Marks 1Marks 2
Air Pollution
Marks 1Marks 2
Noise Pollution
Marks 1
1
GATE CE 2025 Set 2
MCQ (More than One Correct Answer)
+2
-0

A compound has a general formula $\mathrm{C}_{\mathrm{a}} \mathrm{H}_{\mathrm{b}} \mathrm{O}_{\mathrm{c}} \mathrm{N}_{\mathrm{d}}$ and molecular weight 187. A $935 \mathrm{mg} / \mathrm{l}$ solution of the compound is prepared in distilled deionized water. The Total Organic Carbon (TOC) is measured as $360 \mathrm{mg} / \mathrm{l}$ (as C). The Chemical Oxygen Demand (COD) and the Total Kjeldahl Nitrogen (TKN) are determined as $600 \mathrm{mg} / \mathrm{l}$ (as $\mathrm{O}_2$ ) and $140 \mathrm{mg} /$ I (as N), respectively (as per the chemical equation given below). Which of the following ptions is/are CORRECT?

$$ \mathrm{C}_{\mathrm{a}} \mathrm{H}_{\mathrm{b}} \mathrm{O}_{\mathrm{c}} \mathrm{~N}_{\mathrm{d}}+\frac{(4 \mathrm{a}+\mathrm{b}-2 \mathrm{c}-3 \mathrm{~d})}{4} \mathrm{O}_2 \rightarrow \mathrm{aCO}_2+\frac{\mathrm{b}-3 \mathrm{~d}}{2} \mathrm{H}_2 \mathrm{O}+\mathrm{dNH}_3 $$

Atomic weight : $\mathrm{C}(12), \mathrm{H}(1), \mathrm{O}(16), \mathrm{N}(14)$

A
$\mathrm{a}=6$
B
$\mathrm{b}=7$
C
$\mathrm{c}=5$
D
$d=3$
2
GATE CE 2023 Set 2
Numerical
+2
-0

The theoretical aerobic oxidation of biomass (C5H7O2N) is given below:

C5H7O2N + 5O2 → 5CO2 + NH3 + 2H2O

The biochemical oxidation of biomass is assumed as a first-order reaction with a rate constant of 0.23/d at 20ºC (logarithm to base e). Neglecting the second-stage oxygen demand from its biochemical oxidation, the ratio of BOD5 at 20ºC to total organic carbon (TOC) of biomass is _______ (round off to two decimal places).

[Consider the atomic weights of C, H, O and N as 12 g/mol, 1 g/mol, 16 g/mol and 14 g/mol, respectively

Your input ____
3
GATE CE 2022 Set 1
Numerical
+2
-0

A 2% sewage sample (in distilled water) was incubated for 3 days at 27$$^\circ$$C temperature. After incubation, a dissolved oxygen depletion of 10 mg/L was recorded. The biochemical oxygen demand (BOD) rate constant at 27$$^\circ$$C was found to be 0.23 day$$-$$1 (at base e). The ultimate BOD (in mg/L) of the sewage will be ________. (round off to the nearest integer)

Your input ____
GATE CE Subjects
Engineering Mechanics
Strength of Materials Or Solid Mechanics
Structural Analysis
Construction Material and Management
Reinforced Cement Concrete
Steel Structures
Geotechnical Engineering
Fluid Mechanics and Hydraulic Machines
Hydrology
Irrigation
Geomatics Engineering Or Surveying
Environmental Engineering
Transportation Engineering
Engineering Mathematics
General Aptitude