6.If the initial DO concentration of a diluted (1/50) wastewater sample is 9.0 mg/L and theUO concentration decreases to 2.4 mg/L after 5 days of incubation,a. calculate the 5-day BOD concentration in mg/L:b. If the wastewater degrades at a rate of 0.22/day, what is the ultimate BOD concentration?c. Based on the k value in part (b), what would the BOD concentration be after 10 days?d. What other factor may influence the BOD that is not accounted for in part (c)?

a. To calculate the 5-day BOD concentration, you'll use the following formula:BOD5 = (Initial DO -…

Answered: 6. If the initial DO concentration of a…

Solid Waste Engineering

3rd Edition

ISBN:9781305635203

Author:Worrell, William A.

Publisher:Worrell, William A.

Chapter6: Biological Processes

Section: Chapter Questions

Problem 6.1P

See similar textbooks

Similar questions

A hydrometer test has the following result: Gs = 2.65, temperature of water = 26 C, and L = 10.4 cm at 45 minutes after the start of sedimentation (see Figure 2.25). What is the diameter D of the smallest-size particles that have settled beyond the zone of measurement at that time (that is, t = 45 min)? Figure 2.25 ASTM 152H type of hydrometer placed inside the sedimentation cylinder (Courtesy of Khaled Sobhan, Florida Atlantic University, Boca Raton, Florida)
An existing rural 4-lane highway is to be replaced by a 6-lane divided expressway (3 lanes in each direction). Traffic volume data on the highway indicate that the AADT (both directions) during the first year of operation is 24,000 with the following vehicle mix and axle loads. Passengercars=50percent 2-axle single-unit trucks (12,000lb/axle)=40percent 3-axle single-unit trucks (16,000lb/axle)=10percent The vehicle mix is expected to remain the same throughout the design life of 20 years, although traffic is expected to grow at a rate of 3.5 percent annually. Using the AASHTO design procedure, determine the minimum depth of concrete pavement required for the design period of 20 years. Pi=4.5J=3.2Pt=2.5Cd=1.0Sc=650lb/in.2So=0.3Ec=5106lb/in.2R=95k=130lb/in.3
Two materials, A and B, are to be separated using two unit operations, 1 and 2. The feed has 10 tons/h A and 4 tons/h B. The split (fraction of material rejected by each operation) is given in Table P5-14. a. Which sequence of operations, (l?2) or (2?1), will yield the greatest recovery of material A? b. What will be the purity of material A using that sequence? c. What will be the efficiency of separation for the entire process train with regard to material A using the Worrell-Stesed equation?
Repeat Problem 2.14 with the following values: Gs = 2.75, temperature of water = 21C, t = 88 min, and L = 11.7 cm. 2.14 A hydrometer test has the following result: Gs = 2.65, temperature of water = 26 C, and L = 10.4 cm at 45 minutes after the start of sedimentation (see Figure 2.25). What is the diameter D of the smallest-size particles that have settled beyond the zone of measurement at that time (that is, t = 45 min)? Figure 2.25 ASTM 152H type of hydrometer placed inside the sedimentation cylinder (Courtesy of Khaled Sobhan, Florida Atlantic University, Boca Raton, Florida)
Refer to Figure 7.24. The following data were collected during the field permeability measurement of a confined aquifer using a pumping test. Determine the hydraulic conductivity of the permeable layer. Use Eq. (7.49). Thickness of the aquifer, H = 4.5 m Piezometric level and radial distance of the first observation well: h1 = 2.9 m; r1 = 17.8 m Piezometric level and radial distance of the second observation well: h2 = 1.8 m; r2 = 8.1 m Rate of discharge from pumping, q = 0.5 m3/min
Refer to Problem 2.C.1. Results of the sieve analysis for Soils A, B, and C are given below. To obtain a more representative sample for further geotechnical testing, a ternary blend is created by uniformly mixing 8000 kg of each soil. Answer the following questions. a. If a sieve analysis is conducted on the mixture using the same set of sieves as shown above, compute the mass retained (as a percentage) and cumulative percent passing in each sieve. b. What would be the uniformity coefficient (Cu) and the coefficient of gradation (Cc) of the mixture?

Recommended textbooks for you

Solid Waste Engineering

Civil Engineering

ISBN:

9781305635203

Author:

Worrell, William A.

Publisher:

Cengage Learning,

Fundamentals of Geotechnical Engineering (MindTap…

Civil Engineering

ISBN:

9781305635180

Author:

Braja M. Das, Nagaratnam Sivakugan

Publisher:

Cengage Learning

Principles of Geotechnical Engineering (MindTap C…

Civil Engineering

ISBN:

9781305970939

Author:

Braja M. Das, Khaled Sobhan

Publisher:

Cengage Learning

Solid Waste Engineering

Civil Engineering

ISBN:

9781305635203

Author:

Worrell, William A.

Publisher:

Cengage Learning,

Fundamentals of Geotechnical Engineering (MindTap…

Civil Engineering

ISBN:

9781305635180

Author:

Braja M. Das, Nagaratnam Sivakugan

Publisher:

Cengage Learning

Principles of Geotechnical Engineering (MindTap C…

Civil Engineering

ISBN:

9781305970939

Author:

Braja M. Das, Khaled Sobhan

Publisher:

Cengage Learning

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

Principles of Foundation Engineering (MindTap Cou…

Civil Engineering

ISBN:

9781305081550

Author:

Braja M. Das

Publisher:

Cengage Learning

SEE MORE TEXTBOOKS