Recent activity in Environmental Engineering

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1

GATE Civil 2021 Set 2 | Question: 51
An activated sludge process $\text{(ASP)}$ is designed for secondary treatment of $7500\:m^{3}/$day of municipal wastewater. After primary clarifier, the ultimate $\text{BOD}$ of the influent, which enters into $\text{ASP}$ ... underflow volume (in $m^{3}$/day, $\textit{round off to one decimal place}$) of sludge wastage is _______________________

An activated sludge process $\text{(ASP)}$ is designed for secondary treatment of $7500\:m^{3}/$day of municipal wastewater. After primary clarifier, the ultimate $\text{...

110 points

ishita29 answered Feb 3, 2023

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2

GATE2014-1-46
$16$ MLD of water is flowing through a $2.5$ km long pipe of diameter $45$ cm. The chlorine at the rate of $32$ kg/d is applied at the entry of this pipe so that disinfected water is obtained at the exit. There is a proposal to increase the flow through this ... per day) to be applied to achieve the same degree of disinfection for the enhanced flow is $60.50$ $44.00$ $38.00$ $23.27$

$16$ MLD of water is flowing through a $2.5$ km long pipe of diameter $45$ cm. The chlorine at the rate of $32$ kg/d is applied at the entry of this pipe so that disinfec...

100 points

Chandanachandu recategorized May 30, 2021

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3

GATE2014-1-21
Some of the nontoxic metals normally found in natural water are arsenic lead and mercury calcium sodium and silver cadmium, chromium and copper iron, manganese and magnesium

Some of the nontoxic metals normally found in natural water arearsenic lead and mercurycalcium sodium and silvercadmium, chromium and copperiron, manganese and magnesium

100 points

Chandanachandu recategorized May 30, 2021

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4

GATE2014-1-48
For a sample water with the ionic composition shown in the figure below, the carbonate and non-carbonate hardness concentrations (in mg/l as $CaCO_3$), respectively are: $200$ and $50$ $175$ and $75$ $75$ and $175$ $50$ and $200$

For a sample water with the ionic composition shown in the figure below, the carbonate and non-carbonate hardness concentrations (in mg/l as $CaCO_3$), respectively are:$...

100 points

Chandanachandu edited May 29, 2021

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5

GATE2014-2-21
The dominating microorganisms in an activated sludge process reactor are aerobic heterotrophs anaerobic heterotrophs autotrophs phototrophs

The dominating microorganisms in an activated sludge process reactor areaerobic heterotrophsanaerobic heterotrophsautotrophsphototrophs

100 points

Chandanachandu edited May 29, 2021

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6

GATE2014-2-47
A surface water treatment plant operates round the clock with a flow rate of $35 \: m^3/min$. The water temperature is $15^{\circ}C$ and jar testing indicated an alum dosage of $25$ mg/l with flocculation at a $Gt$ value of $4 \times 10^4$ producing optimal results. The alum quantity required for $30$ days (in kg) of operation of the plant is _______

A surface water treatment plant operates round the clock with a flow rate of $35 \: m^3/min$. The water temperature is $15^{\circ}C$ and jar testing indicated an alum dos...

100 points

Chandanachandu retagged May 29, 2021

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GATE2014-2-48
An effluent at a flow rate of $2670 \: m^3/d$ from a sewage treatment plant is to be disinfected. The laboratory data of disinfection studies with a chlorine dosage of $15$ mg/l yield the model $N_t=N_oe^{-0.145t}$ where $N_t=$ number of micro-organisms surviving ... (at $t=0$). The volume of disinfection unit (in $m^3$) required to achieve a $98\%$ kill micro-organisms is __________

An effluent at a flow rate of $2670 \: m^3/d$ from a sewage treatment plant is to be disinfected. The laboratory data of disinfection studies with a chlorine dosage of $1...

100 points

Chandanachandu retagged May 29, 2021

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8

GATE2014-2-49
A waste water stream (flow $=2 m^3/s$, ultimate BOD$=90$ mg/l) is joining a small river (flow $=12 \: m^3/s$, ultimate BOD $=5$ mg/l). Both water streams get mixed up instantaneously. Cross-sectional area of the river is $50 \: m^2$. Assuming the de-oxygenation rate ... $10$ km downstream of the mixing point is $1.68$ $12.63$ $15.46$ $1.37$

A waste water stream (flow $=2 m^3/s$, ultimate BOD$=90$ mg/l) is joining a small river (flow $=12 \: m^3/s$, ultimate BOD $=5$ mg/l). Both water streams get mixed up ins...

100 points

Chandanachandu edited May 29, 2021

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GATE Civil 2013 | Question: 20
Some of the water quality parameters are measured by titrating a water sample with a titrant. Group I gives a list of parameters and Group-II gives the list of titrants. ... $P - 2, Q - 1, R - 4, S - 3$ $P - 4, Q - 3, R - 2, S - 1$

Some of the water quality parameters are measured by titrating a water sample with a titrant. Group I gives a list of parameters and Group-II gives the list of titrants.$...

100 points

Chandanachandu recategorized May 29, 2021

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10

GATE Civil 2013 | Question: 21
A water treatment plant is designed to treat $1 \: m^3/s$ of raw water. It has $14$ sand filters. Surface area of each filter is $50 \: m^2$. What is the loading rate (in $\dfrac{m^3}{\text{day} \cdot m^2}$) with two filters out of service for routine backwashing? __________

A water treatment plant is designed to treat $1 \: m^3/s$ of raw water. It has $14$ sand filters. Surface area of each filter is $50 \: m^2$. What is the loading rate (in...

100 points

Chandanachandu retagged May 29, 2021

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11

GATE Civil 2013 | Question: 43
A student began experiment for determination of $5$-day, $20^{\circ}C$ BOD on Monday. Since the $5$th day fell on Saturday, the final DO readings were taken on next Monday. On calculation, BOD (i.e. $7$ day, $20^{\circ}C$ was found to be $150$ ... )? Assume value of BOD rate constant $(k)$ at standard temperature of $20^{\circ}C$ as $0.23/day$ (base $e$). ___________

A student began experiment for determination of $5$-day, $20^{\circ}C$ BOD on Monday. Since the $5$th day fell on Saturday, the final DO readings were taken on next Monda...

100 points

Chandanachandu recategorized May 29, 2021

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GATE Civil 2013 | Question: 42
A settling tank in a water treatment plant is designed for a surface overflow rate of $30 \dfrac{m^3}{\text{day} \cdot m^2}$. Assume specific gravity of sediment particles $=2.65$, density of water $(\rho) =1000 \: kg/m^3$, dynamic viscosity of ... The approximate minimum size of particles that would be completely removed is $0.01$ mm $0.02$ mm $0.03$ mm $0.04$ mm

A settling tank in a water treatment plant is designed for a surface overflow rate of $30 \dfrac{m^3}{\text{day} \cdot m^2}$. Assume specific gravity of sediment particle...

100 points

Chandanachandu retagged May 29, 2021

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13

GATE Civil 2012 | Question: 50
An activated sludge system (sketched below) is operating at equilibrium with the following information. Wastewater related data: flow rate $= 500 \: m^3/hour$, influent BOD $=150 \: mg/L$, effluent BOD $=10 \: mg/L$. Aeration tank related data: hydraulic retention ... ratio (in kg BOD per kg biomass per day) for the aeration tank is $0.015$ $0.210$ $0.225$ $0.240$

An activated sludge system (sketched below) is operating at equilibrium with the following information. Wastewater related data: flow rate $= 500 \: m^3/hour$, influent B...

100 points

Chandanachandu edited May 29, 2021

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14

GATE Civil 2012 | Question: 51
An activated sludge system (sketched below) is operating at equilibrium with the following information. Wastewater related data: flow rate $=500 \: m^3/hour$, influent BOD $= 150 mg/L$, effluent BOD $=10 \: mg/L$ ... $24000$ $1000$ $800$ $33$

An activated sludge system (sketched below) is operating at equilibrium with the following information. Wastewater related data: flow rate $=500 \: m^3/hour$, influent BO...

100 points

Chandanachandu edited May 29, 2021

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15

GATE Civil 2012 | Question: 42
A water sample has a pH of $9.25$. The concentration of hydroxyl ions in the water sample is $10^{-9.25}$ moles/L $10^{-4.75}$ mmoles/L $0.302$ mg/L $3.020$ mg/L

A water sample has a pH of $9.25$. The concentration of hydroxyl ions in the water sample is$10^{-9.25}$ moles/L$10^{-4.75}$ mmoles/L$0.302$ mg/L$3.020$ mg/L

100 points

Chandanachandu recategorized May 29, 2021

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16

GATE Civil 2012 | Question: 43
A town is required to treat $4.2 \: m^3/min$ of raw water for daily domestic supply. Flocculating particles are to be produced by chemical coagulation. A column analysis indicated that an overflow rate of $0.2$ mm/s will produce satisfactory particles removal in a ... depth of $3.5$ m. The required surface area (in $m^2$) for settling is $210$ $350$ $1728$ $21000$

A town is required to treat $4.2 \: m^3/min$ of raw water for daily domestic supply. Flocculating particles are to be produced by chemical coagulation. A column analysis ...

100 points

Chandanachandu edited May 29, 2021

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17

GATE Civil 2012 | Question: 20
A sample of domestic sewage is digested with silver sulphate, sulphuric acid, potassium dichromate and mercuric sulphate in chemical oxygen demand (COD) test. The digested sample is then titrated with standard ferrous ammonium sulphate (FAS) to determine the un-reacted amount of mercuric sulphate potassium dichromate silver sulphate sulphuric acid

A sample of domestic sewage is digested with silver sulphate, sulphuric acid, potassium dichromate and mercuric sulphate in chemical oxygen demand (COD) test. The digeste...

100 points

Chandanachandu edited May 29, 2021

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GATE Civil 2012 | Question: 21
... $\textbf{[a]}$ and $\textbf{[r]}$ are false $\textbf{[a]}$ is true but $\textbf{[r]}$ is false

$\begin{array}{lcl} \textbf{Assertion [a]} &: & \text{At a manhole, the crown of the outgoing sewer should not be higher} \\ & & \text{than the crown of the incoming sewe...

100 points

Chandanachandu retagged May 29, 2021

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19

GATE2015-2-47
A landfill is to be designed to serve a population of $200000$ for a period of $25$ years. The solid waste (SW) generation is $2$ kg/person/day. The density of the un-compacted SW is $100 \: kg/m^3$ and a compaction ratio of $4$ is suggested. The ratio of compacted fill (i.e., SW+cover) to compacted SW is $1.5$. The landfill volume (in $million \: m^3$) required is _________.

A landfill is to be designed to serve a population of $200000$ for a period of $25$ years. The solid waste (SW) generation is $2$ kg/person/day. The density of the un-com...

100 points

Chandanachandu retagged May 28, 2021

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20

GATE2015-2-50
In a wastewater treatment plant, primary sedimentation tank (PST) designed at an overflow rate of $32.5 \: m^3/day/m^2$ is $32.5$ m long, $8.0$ m wide and liquid depth of $2.25$ m. If the length of the weir is $75$ m, the weir loading rate (in $m^3/day/m$) is ______.

In a wastewater treatment plant, primary sedimentation tank (PST) designed at an overflow rate of $32.5 \: m^3/day/m^2$ is $32.5$ m long, $8.0$ m wide and liquid depth of...

100 points

Chandanachandu retagged May 28, 2021

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21

GATE2015-1-20
Total Kjeldahl Nitrogen (TKN) concentration (mg/L as N) in domestic sewage is the sum of the concentrations of organic and inorganic nitrogen in sewage organic nitrogen and nitrate in sewage organic nitrogen and ammonia in sewage ammnia and nitrate in sewage

Total Kjeldahl Nitrogen (TKN) concentration (mg/L as N) in domestic sewage is the sum of the concentrations oforganic and inorganic nitrogen in sewageorganic nitrogen and...

100 points

Chandanachandu edited May 28, 2021

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22

GATE2015-1-21
Solid waste generated from an industry contains only two components, X and Y as shown in the table below. ... $100(c_1 \rho_1 +c_2 \rho_2) \\$ $100 \bigg( \dfrac{\rho_1 \rho_2}{c_1 \rho_1 + c_2 \rho_2} \bigg)$

Solid waste generated from an industry contains only two components, X and Y as shown in the table below.$$\begin{array}{ccc} \textbf{Component} & \textbf{Composition} & ...

100 points

Chandanachandu recategorized May 28, 2021

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23

GATE2015-1-49
The concentration of Sulfur Dioxide $(SO_2)$ in ambient atmosphere was measured as $30 \: \mu g /m^3$. Under the same conditions, the above $SO_2$ concentration expressed in ppm is _________. Given: $P/(RT) = 41.6 \: mol/m^3$; where, $P=$ Pressure; $T=$ Temperature; $R=$ universal gas constant; Molecular weight of $SO_2 =64$.

The concentration of Sulfur Dioxide $(SO_2)$ in ambient atmosphere was measured as $30 \: \mu g /m^3$. Under the same conditions, the above $SO_2$ concentration expressed...

100 points

Chandanachandu recategorized May 27, 2021

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24

GATE2015-1-50
Consider a primary sedimentation tank (PST) in a water treatment plant with Surface Overflow Rate (SOR) of $40\:m^3/m^2/d$. The diameter of the spherical particle which will have $90$ percent theoretical removal efficiency in this tank is ______ $\mu m$. Assume that settling velocity of the ... $g=9.81 \: m/s^2$; Kinematic viscosity of water $(v) = 1.10 \times 10^{-6} m^2/s$.

Consider a primary sedimentation tank (PST) in a water treatment plant with Surface Overflow Rate (SOR) of $40\:m^3/m^2/d$. The diameter of the spherical particle which w...

100 points

Chandanachandu retagged May 27, 2021

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25

GATE2016-2-18
A water supply board is responsible for treating $1500 \:m^3/day$ of water. A settling column analysis indicates that an overflow rate of $20 \: m/day$ will produce satisfactory removal for a depth of $3.1 \: m$. It is decided to have two circular settling tanks in parallel. The required diameter (expressed in $m$) of the settling tank is __________

A water supply board is responsible for treating $1500 \:m^3/day$ of water. A settling column analysis indicates that an overflow rate of $20 \: m/day$ will produce satis...

100 points

Chandanachandu recategorized May 27, 2021

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26

GATE2016-2-19
The hardness of a ground water sample was found to be $420 \: mg/L$ as $CaCO_3$. A softener containing ion exchange resins was installed to reduce the total hardness to $75 \: mg/L$ as $CaCO_3$ before supplying to $4$ households. Each household gets treated water at ... $100\%$, the bypass flow rate (expressed in $L/day$) is _________

The hardness of a ground water sample was found to be $420 \: mg/L$ as $CaCO_3$. A softener containing ion exchange resins was installed to reduce the total hardness to $...

100 points

Chandanachandu recategorized May 27, 2021

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27

GATE2016-2-20
The sound pressure (expressed in $\mu P a$) of the faintest sound that a normal healthy individual can hear is $0.2$ $2$ $20$ $55$

The sound pressure (expressed in $\mu P a$) of the faintest sound that a normal healthy individual can hear is$0.2$$2$$20$$55$

100 points

Chandanachandu recategorized May 27, 2021

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28

GATE2016-2-50
A sample of water has been analyzed for common ions and results are presented in the form of a bar diagram as shown. The non-carbonate hardness (expressed in mg/L as $CaCO_3$) of the sample is $40$ $165$ $195$ $205$

A sample of water has been analyzed for common ions and results are presented in the form of a bar diagram as shown.The non-carbonate hardness (expressed in mg/L as $CaCO...

100 points

Chandanachandu edited May 27, 2021

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29

GATE2016-2-52
For a wastewater sample, the three-day biochemical oxygen demand at incubation temperature of $20^{\circ}C$ (BOD$_{\text{3day}, 20^{\circ}C}$) is estimated as $200 mg/L$ ... in mg/L) of the wastewater at incubation temperature of $20^{\circ}C$ (BOD$_{\text{5day}, 20^{\circ}C}$) would be ________

For a wastewater sample, the three-day biochemical oxygen demand at incubation temperature of $20^{\circ}C$ (BOD$_{\text{3day}, 20^{\circ}C}$) is estimated as $200 mg/L$....

100 points

Chandanachandu retagged May 27, 2021

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30

GATE2016-1-17
Pre-cursors to photochemical oxidants are $NO_X, \: VOC$s and sunlight $SO_2, \: CO_2$ and sunlight $H_2S, \: CO$ and sunlight $SO_2, \: NH_3$ and sunlight

Pre-cursors to photochemical oxidants are$NO_X, \: VOC$s and sunlight$SO_2, \: CO_2$ and sunlight$H_2S, \: CO$ and sunlight$SO_2, \: NH_3$ and sunlight

100 points

Chandanachandu recategorized May 27, 2021

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31

GATE2016-1-19
It was decided to construct a fabric filter, using bags of $0.45$ m diameter and $7.5$ m long, for removing industrial stack gas containing particulates. The expected rate of airflow into the filter is $10 \: m^3/s$. If the filtering velocity is $2.0$ m/min, the minimum number of bags (rounded to nearest higher integer) required for continuous cleaning operation is $27$ $29$ $31$ $32$

It was decided to construct a fabric filter, using bags of $0.45$ m diameter and $7.5$ m long, for removing industrial stack gas containing particulates. The expected rat...

100 points

Chandanachandu recategorized May 27, 2021

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32

GATE2016-1-20
Match the items in Group - I with those in Group - II and choose the right combination. ... $P - 1; \: Q - 4; \: R - 2; \: S - 3$

Match the items in Group – I with those in Group – II and choose the right combination.$$\begin{array}{llll} {} & \underline{\text{Group – I}} & {} & \underline{\...

100 points

Chandanachandu retagged May 27, 2021

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33

GATE2016-1-50
Effluent from an industry ‘A’ has a pH of $4.2$. The effluent from another industry ‘B’ has double the hydroxyl (OH) ion concentration than the effluent from industry ‘A’. pH of effluent from the industry ‘B’ will be ______

Effluent from an industry ‘A’ has a pH of $4.2$. The effluent from another industry ‘B’ has double the hydroxyl (OH) ion concentration than the effluent from indu...

100 points

Chandanachandu retagged May 27, 2021

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34

GATE2016-1-51
An electrostatic precipitator (ESP) with $5600\:m^2$ of collector plate area is $96$ percent efficient in treating $185\:m^3/s$ of flue gas from a $200$ MW thermal power plant. It was found that in order to achieve $97$ percent efficiency, the collector plate ... $99$ percent, the ESP collector plate area (expressed in $m^2$) would be ______

An electrostatic precipitator (ESP) with $5600\:m^2$ of collector plate area is $96$ percent efficient in treating $185\:m^3/s$ of flue gas from a $200$ MW thermal power ...

100 points

Chandanachandu recategorized May 27, 2021

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35

GATE2016-1-52
The $2$-day and $4$-day BOD values of a sewage sample are $100$ mg/L and $155$ mg/L, respectively. The value of BOD rate constant (expressed in per day) is __________

The $2$-day and $4$-day BOD values of a sewage sample are $100$ mg/L and $155$ mg/L, respectively. The value of BOD rate constant (expressed in per day) is __________

100 points

Chandanachandu recategorized May 27, 2021

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36

GATE2017 CE-2-52
A municipal corporation is required to treat $1000 \: m^3/day$ of water. It is found that an overflow rate of $20 m/day$ will produce a satisfactory removal of the discrete suspended particles at a depth of $3 m$. The diameter (in meters, round to the nearest integer) of a circular settling tank designed for the removal of these particles would be ___________

A municipal corporation is required to treat $1000 \: m^3/day$ of water. It is found that an overflow rate of $20 m/day$ will produce a satisfactory removal of the discre...

100 points

Chandanachandu recategorized May 25, 2021

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37

GATE2017 CE-2-51
For a given water sample, the ratio between BOD$_{\text{5-day, 20}^{\circ} C}$ and the ultimate BOD is $0.68$. The value of the reaction rate constant $k$ (on base $e$) (in day$^{-1}$, up to two decimal places) is ________

For a given water sample, the ratio between BOD$_{\text{5-day, 20}^{\circ} C}$ and the ultimate BOD is $0.68$. The value of the reaction rate constant $k$ (on base $e$) (...

100 points

Chandanachandu retagged May 25, 2021

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38

GATE2017 CE-2-50
The composition of a municipal solid waste sample is given below: ... The difference between the energy content of the waste sample calculated on dry basis and as-discarded basis (in kJ/kg) would be _______

The composition of a municipal solid waste sample is given below:$\begin{array}{|l|c|c|c|} \hline \text{Component} & \text{Percent by} & \text{Moisture Content} & \text{E...

100 points

Chandanachandu recategorized May 25, 2021

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39

GATE2017 CE-2-10
The most important type of species involved in the degradation of organic matter in the case of activated sludge process is autotrophs heterotrophs prototrophs photo-autotrophs

The most important type of species involved in the degradation of organic matter in the case of activated sludge process isautotrophsheterotrophsprototrophsphoto-autotrop...

100 points

Chandanachandu edited May 25, 2021

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40

GATE2017 CE-2-9
Following observations have ben made for the elevation and temperature to ascertain the stability of the atmosphere: $\begin{array}{|c|c|} \hline \text{Elevation (in m) } & \text{Temperature (in }^{\circ} \text{C)} \\ \hline 10 & 15.5 \\ \hline 60 & 15.0 \\ \hline 130 & 14.3 \\ \hline \end{array}$ The atmosphere is classified as Stable Unstable Neutral Inverse

Following observations have ben made for the elevation and temperature to ascertain the stability of the atmosphere:$$\begin{array}{|c|c|} \hline \text{Elevation (in m) }...

100 points

Chandanachandu recategorized May 25, 2021

1 votes

1 answer

41

GATE2017 CE-1: 55
The wastewater having an organic concentration of $54$ mg/l is flowing at a steady rate of $0.8 \: m^3/day$ through a detention tank of dimensions $2m \times 4 m \times 2 m$. If the contents of the tank are well mixed and the decay constant $0.1$ per day, the outlet concentration (in mg/l, up to one decimal place) is _________

The wastewater having an organic concentration of $54$ mg/l is flowing at a steady rate of $0.8 \: m^3/day$ through a detention tank of dimensions $2m \times 4 m \times 2...

100 points

Chandanachandu retagged May 25, 2021

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42

GATE2017 CE-1: 14
The wastewater from a city, containing a high concentration of biodegradable organics, is being steadily discharged into a flowing river at a location S. If the rate of aeration of the river water is lower than the rate of degradation of the organics, then the ... the location S. remains constant all along the length of the river. is lowest at a point downstream of the location S.

The wastewater from a city, containing a high concentration of biodegradable organics, is being steadily discharged into a flowing river at a location S. If the rate of a...

100 points

Chandanachandu recategorized May 25, 2021

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43

GATE2017 CE-1: 52
The equivalent sound power level (in dB) of the four sources with the noise levels of $60$ dB, $69$ dB, $70$ dB and $79$ dB is ______

The equivalent sound power level (in dB) of the four sources with the noise levels of $60$ dB, $69$ dB, $70$ dB and $79$ dB is ______

100 points

Chandanachandu retagged May 25, 2021

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44

GATE2017 CE-1: 54
Two wastewater streams A and B, having an identical ultimate BOD are getting mixed to form the stream C. The temperature of the stream A is $20^{\circ}C$ and the temperature of the stream C is $10^{\circ}C$. It is given that the $5$-day BOD of the stream A measured ... The $5-$day BOD (in mg\I, up to one decimal place ) of the stream C, calculated at $10^{\circ} C$, is _________

Two wastewater streams A and B, having an identical ultimate BOD are getting mixed to form the stream C. The temperature of the stream A is $20^{\circ}C$ and the temperat...

100 points

Chandanachandu edited May 25, 2021

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45

GATE2018 CE-2: 52
A schematic flow diagram of a completely mixed biological reactor with provision for recycling of solids shown in the figure. $S_0$, $S$ = readily biodegradable soluble BOD, mg/L $Q, \: Q_r, \: Q_w$ = flow rates $m^3/d$ ... (mixed liquor soils volatile suspended solids or MLVSS ), mg/l The mean cell residence time (in days, up to one decimal place) is _____

A schematic flow diagram of a completely mixed biological reactor with provision for recycling of solids shown in the figure. $S_0$, $S$ = readily biodegradable soluble B...

100 points

Chandanachandu recategorized May 23, 2021

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1 answer

46

GATE2018 CE-2: 14
As per $\text{IS }10500:2012$, for drinking water in the absence of alternate source of water, the permissible limits for chloride and sulphate, in mg/L, respectively are $250$ and 200$ $1000$ and 400$ $200$ and 250$ $500$ and 1000$

As per $\text{IS }10500:2012$, for drinking water in the absence of alternate source of water, the permissible limits for chloride and sulphate, in mg/L, respectively are...

100 points

Chandanachandu recategorized May 23, 2021

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47

GATE2018 CE-2: 15
In the figures, Group I represents the atmospheric temperature profiles (P, Q, R and S) and Group II represents dispersion of pollutants from a smoke stack $(1, 2, 3$ and $4)$. In the figures of Group I, the dashed line represents the dry adiabatic lapse rate, whereas the horizontal axis represents temperature and ... $P-1, Q-4, R-3, S-2$ $P-3, Q-1, R-2, S-4$

In the figures, Group I represents the atmospheric temperature profiles (P, Q, R and S) and Group II represents dispersion of pollutants from a smoke stack $(1, 2, 3$ and...

100 points

Chandanachandu recategorized May 23, 2021

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1 answer

48

GATE2018 CE-2: 51
At a small water treatment plant which has $4$ filters, the rates of filteration and backwashing are $200 \: m^3/d/m^2$ and $1000 m^3/d/m^2$, respectively. Backwashing is done for $15$ min per day. The maturation, which ... the water being wasted during backwashing and maturation. The percentage increase in the filtered water produced (up to two decimal places) would be ______

At a small water treatment plant which has $4$ filters, the rates of filteration and backwashing are $200 \: m^3/d/m^2$ and $1000 m^3/d/m^2$, respectively. Backwashing is...

100 points

Chandanachandu retagged May 22, 2021

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1 answer

49

GATE2018 CE-1: 33
A rapid sand filter comprising a number of filter beds is required to produce $99$ MLD of potable water. Consider water loss during backwashing as $5\%$, rate of filtration as 6.0 m/h and length to width ratio of filter bed as $1.35$. The width of each ... to take care of break-down, repair, and maintenance. The total number of filter beds required will be $19$ $20$ $21$ $22$

A rapid sand filter comprising a number of filter beds is required to produce $99$ MLD of potable water. Consider water loss during backwashing as $5\%$, rate of filtrati...

100 points

Chandanachandu recategorized May 22, 2021

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1 answer

50

GATE2018 CE-1: 52
The ultimate BOD $(L_0)$ of a wastewater sample is estimated as $87 \%$ of COD. The COD of this wastewater is $300$ mg/L. Considering first order BOD reaction rate constant $k$ (use natural log) $= 0.23$ ... value in (in mg/L, up to one decimal place) after three days of incubation at $27^{\circ}$C for this wastewater will be _____

The ultimate BOD $(L_0)$ of a wastewater sample is estimated as $87 \%$ of COD. The COD of this wastewater is $300$ mg/L. Considering first order BOD reaction rate consta...

100 points

Chandanachandu retagged May 22, 2021

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