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
Numerical
+2
-0

The analyses results of a water sample are given below. The non-carbonate hardness of the water (in $\mathrm{mg} / \mathrm{L}$ ) as $\mathrm{CaCO}_3$ is __________ (in integer).

$$ \begin{aligned} & \mathrm{Ca}^{2+}=150 \mathrm{mg} / \mathrm{L} \text { as } \mathrm{CaCO}_3 \\ & \mathrm{Mg}^{2+}=40 \mathrm{mg} / \mathrm{L} \text { as } \mathrm{CaCO}_3 \\ & \mathrm{Fe}^{2+}=10 \mathrm{mg} / \mathrm{L} \text { as } \mathrm{CaCO}_3 \\ & \mathrm{Na}^{+}=50 \mathrm{mg} / \mathrm{L} \text { as } \mathrm{CaCO}_3 \\ & \mathrm{~K}^{+}=10 \mathrm{mg} / \mathrm{L} \text { as } \mathrm{CaCO}_3 \\ & \mathrm{CO}_3{ }^{2-}=120 \mathrm{mg} / \mathrm{L} \text { as } \mathrm{CaCO}_3 \\ & \mathrm{HCO}_3{ }^{-}=30 \mathrm{mg} / \mathrm{L} \text { as } \mathrm{CaCO}_3 \end{aligned} $$

$\mathrm{Cl}^{-}=50 \mathrm{mg} / \mathrm{L}$ as $\mathrm{CaCO}_3$; Other anions were not analysed.

Your input ____
2
GATE CE 2025 Set 1
MCQ (More than One Correct Answer)
+2
-0

$\mathrm{MgCl}_2$ and $\mathrm{CaSO}_4$ salts are added to 1 litre of distilled deionized water and mixed until completely dissolved. Total Dissolved Solids (TDS) concentration is $500 \mathrm{mg} / \mathrm{l}$, and Total Hardness (TH) is $400 \mathrm{mg} / \mathrm{l}$ (as $\mathrm{CaCO}_3$ ). The amounts of $\mathrm{MgCl}_2$ and $\mathrm{CaSO}_4$ added are calculated (rounded off to the nearest integer). Which of the following options is/are true:

Atomic weights: $\mathrm{Ca}(40), \mathrm{Mg}(24), \mathrm{S}(32), \mathrm{O}(16), \mathrm{Cl}(35.5), \mathrm{C}(12)$

A
Amount of $\mathrm{MgCl}_2$ added is 143 mg
B
Amount of $\mathrm{CaSO}_4$ added is 357 mg
C
Amount of $\mathrm{MgCl}_2$ added is 103 mg
D
Amount of $\mathrm{CaSO}_4$ added is 397 mg
3
GATE CE 2024 Set 1
Numerical
+2
-0

Activated carbon is used to remove a pollutant from wastewater in a mixed batch reactor, which follows first-order reaction kinetics.

At a reaction rate of 0.38 /day, the time (in days) required to remove the pollutant by 95% is _______________ (rounded off to 1 decimal place).

Your input ____
4
GATE CE 2024 Set 1
Numerical
+2
-0

A water treatment plant treats 25 MLD water with a natural alkalinity of 4.0 mg/L (as CaCO3). It is estimated that, during the coagulation of this water, 450 kg/day of calcium bicarbonate (Ca(HCO3)2) is required based on the alum dosage.

Consider the atomic weights as: Ca-40, H-1, C-12, O-16.

The quantity of pure quick lime, CaO (in kg) required for this process per day is _______ (rounded off to 2 decimal places).

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