4. Chlorine is used for primary disinfection at a water treatment plant that treats 0.55 m³/s ofreservoir water. Giardia (a protozoan) is the primary pathogen of concern, and the Giardiainactivation rate constant for free chlorine disinfection is 0.55 min¹. Note that theinactivation rate constant is k* in the simplified Chick-Watson equation where:r(N) = -k*Nandk* = kC”The plant achieves 3-log removal (99.9%) of Giardia at pH 7.0 in a plug flow contactchamber using free chlorine concentration of 2.1 mg/L.c. What is the volume of the contact chamber?d. If a CSTR, rather than a PFR, contact chamber were used, what would the requiredvolume need to be?e. Assuming a coefficient of dilution of 0.975, what is the coefficient of specific lethality ofGiardia (L/mg-min) under these conditions?

Given: Flow rate (Q) = 0.55 m³/sGiardia inactivation rate constant (k*) = 0.55 min⁻¹Free chlorine…

Answered: 4. Chlorine is used for primary…

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

Chlorine is used for primary disinfection at a water treatment plant that treats 0.20 m^3/s of reservoir water. Giardia (a protozoan) is the primary pathogen of concern, and the Giardia inactivation rate constant for free chlorine disinfection is 0.53 min^-1. Note that the inactivation rate constant is k* in the simplified Chick-Watson equation where the rate of inactivation r(N):r(N) = -k*N and k* = kC^nThe plant achieves 3-log removal of Giardia at pH 6.0-9.0 in a plug flow contact chamber using free chlorine concentration of 2.0 mg/L. (a) What is the volume of contact chamber?(b) If a CSTR, rather than PFR, contact chamber were used, what would the required volume need to be?(c) What volume of contact chamber would be needed if it were constructed as five separate CSTR chambers in series? The volume asked for is the combined volume of all five separate chambers. (d) Assuming a coefficient of dilution of 1.0, what is the coefficient of specific lethality for Giardia under…
a pond is used to treat a dilute municipal wastewater before the liquid is discharged into a river. the inflow to the pond has a flow rate of 4000 m3/day and a bod concentration of 49mg/l. the volume of the pond is 20000m3. the purpose of the pond is to allow time for the decay of bod to occur before discharge into the environment,in this case a river bod decays in the pond with a first order rate constant equal to 0.25 day. a drinking water tretment abstraction point is located 100m downstream of the pond effluent discharge point for the pond. determine the bod concentration at the outflow of the pond in units of mg/l conclude if the effluent from the pond satisfy with the requirement of the DOE malaysia according to the suitable effluent discharge standard Search Results
Question An effluent at a flow rate of 2670 m³/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 N₁-Noe 0.145t where N₁= number of micro-organisms surviving at time t (in min.) and No= number of micro- organism present initially (at t=0). The volume of disinfection unit (in m³) required to achieve a 98% kill of micro-organisms is_
An analysis of water from a surface source yields the following results: Ions Concentration (mg/l) Ca +2 Mg +2 HCO3 SO²- 60 18 91.5 96 The temporary hardness (as CaCO3) and permanent hardness (as CaCO3) present in the water are
State if the following statements are True or False. Edit the False statement with an appropriate statementa. ( ) To check the charge neutrality, we can compare the sum of the molar concentrations of cations and anions.b. ( ) The indicator microorganism for contamination of drinking water is Cryptosporidium parvus
Poorly treated municipal wastewater is continuously discharged directly into a lake. The discharge from the wastewater plant into the lake occurs at a flow of Qd = 1 m3/hr. The concentration of phosphate (PO43, M = 95 g/mol) in the discharge flow (Cxd) that is decaying with first-order kinetics is 100 mg/L. The lake is a well-mixed water body of 100 m3. (Phosphate is naturally uptaken by algae with a first- order decay rate constant equal to 0.20/day.) The concentration of phosphate in the incoming river (Cx,r) is 10 mg P/L. The incoming river flow rate is Q, = 10 m3/hr. %3D a) Which of the following equations represent the correct mass balance equation? O va = CxQr - CxdQd -QoutCxvout" kCx,outV %3D O 0 = Cx,Qr + CxdQd -QoutCxvout" kCx,outV X,r O 0 = CxQr + CxdQd -QoutCxvout- kV O 0 = Cx,dQr + Cx,,Qd -QoutCxout- kCxoutV
In a titration of dilute sulfuric acid, H2SO4, with sodium hydroxide, NaOH, how many milliliters (mL) of 0.2025 M NaOH is required to neutralize a 20.00-mL sample of 0.425 M H2SO4 according to the following equation? H2SO(aq) + 2NaOH(aq) --> Na2SO4(aq) + 2H2O(l) (A) 10.5 mL (B) 21.0 mL (C) 31.5 mL (D) 42.0 mL
188 RIVERS AND STREAMS 4.10. Fifteen kilograms of a contaminant is spilled into a stream 4 m wide and 2 m deep. (a) If the average velocity in the stream is 0.8 m/s, the longitudinal dispersion coefficient is 0.2 m/s, and the first-order decay constant of the contaminant is 0.05 h-1, determine the maximum concentration in the stream at a drinking-water intake 1 km downstream from the spill. (b) How would this concentration be affected if the decay constant is actually one- half of the estimated value?
A drinking water treatment plant wants to compare the efficacy of three different solid coagulants, Alum [Al(OH)3(s)], Lime (CaCO3(s)), and Ferric Chloride (FeCl3(s)), for removing the phosphate (PO43-) level to 1 mg/L. The following are the equilibrium reactions [and the respective equilibrium constants (or solubility products, Ksp)] that result in phosphate removalfor each solid, the second reaction being more relevant in each case: Alum: Al(OH)3(s) ↔ Al3+ + 3OH- AlPO4(s) ↔ Al3+ + PO43- Ksp = 9.84 x 10-21 Lime: CaCO3(s) ↔ Ca2+ + CO32- Ca3(PO4)2(s) ↔ Ca2+ + PO43- Ksp = 1 x10-27 Ferric Chloride: FeCl3 (s) ↔ Fe3+ + 3Cl- Fe(PO4)(s) ↔ Fe3+ + PO43- Ksp = 1x10-26.4 What concentrations of Fe 3+, Al3+, and Ca2+ will be needed to maintain a phosphate concentration of 1 mg/L? What would be the best choice of solid coagulant for the Drinking Water Treatment Plant?…
Q#2a) Dissolved oxygen (D0) is influenced by which factors? Explain.
2. Families in a community in a developing country use large, 200.0 L drums to un-treated surface water. You are designing a device that is designed to dose the volume with a coagulant, stir to allow flocculation, then add chlorine tablets to disinfect the water. The water is 25 °C and initially contains 1.0E+09 particles per L. The initial particles can be assumed to be spherical, 15.0 micrometers in diameter, and with a density of 1.675 g/mL. a. If the drums have a diameter of 572 mm, how long will it take for the particles to completely settle without any coagulation or flocculation? (answer in seconds) You have determined that you can achieve complete destabilization of particles by achieving an ionic strength of 0.01 M or higher. If you use alum (Al2(SO4)3) as a coagulating agent, what mass of alum must be added per batch of 200 L? (answer in grams) How many joules of energy would be required to stir the drum at a mixing intensity of 150 s-' for 20 minutes? If the drum is stirred…
A waste water is to be disinfected with chlorine to kill 90% of microorganisms. The number of micro-organisms surviving at time 't is modelled by N₁ = No 1+kt' where N is number of microorganisms at t = 0, and k is rate of kill in min-1. It was observed that after 10 minutes, 50% of micro-organisms were killed, and after 15 minutes from start, temperature is raised such that kill rate becomes double. The time taken in killing of micro-organisms from 0.5 No to 0.9 No is

SEE MORE QUESTIONS

Recommended textbooks for you

Structural Analysis

Civil Engineering

ISBN:

9781337630931

Author:

KASSIMALI, Aslam.

Publisher:

Cengage,

Structural Analysis (10th Edition)

Civil Engineering

ISBN:

9780134610672

Author:

Russell C. Hibbeler

Publisher:

PEARSON

Principles of Foundation Engineering (MindTap Cou…

Civil Engineering

ISBN:

9781337705028

Author:

Braja M. Das, Nagaratnam Sivakugan

Publisher:

Cengage Learning

Structural Analysis

Civil Engineering

ISBN:

9781337630931

Author:

KASSIMALI, Aslam.

Publisher:

Cengage,

Structural Analysis (10th Edition)

Civil Engineering

ISBN:

9780134610672

Author:

Russell C. Hibbeler

Publisher:

PEARSON

Principles of Foundation Engineering (MindTap Cou…

Civil Engineering

ISBN:

9781337705028

Author:

Braja M. Das, Nagaratnam Sivakugan

Publisher:

Cengage Learning

Fundamentals of Structural Analysis

Civil Engineering

ISBN:

9780073398006

Author:

Kenneth M. Leet Emeritus, Chia-Ming Uang, Joel Lanning

Publisher:

McGraw-Hill Education

Sustainable Energy

Civil Engineering

ISBN:

9781337551663

Author:

DUNLAP, Richard A.

Publisher:

Cengage,

Traffic and Highway Engineering

Civil Engineering

ISBN:

9781305156241

Author:

Garber, Nicholas J.

Publisher:

Cengage Learning

SEE MORE TEXTBOOKS