7-7 A monomedia anthracite filter has an effective size of 1.0 mm and media density of 1650 kg/m. a. Calculate backwash rate to get a 25 percent expansion at the design summer temperature of 25°C. b. Calculate the expansion that occurs at the backwash rate deter- mined in part (a) at the minimum winter temperature of 5°C. c. Discuss the implications of these results on backwash operations for plants that experience a large seasonal variation in water temperature.
7-7 A monomedia anthracite filter has an effective size of 1.0 mm and media density of 1650 kg/m. a. Calculate backwash rate to get a 25 percent expansion at the design summer temperature of 25°C. b. Calculate the expansion that occurs at the backwash rate deter- mined in part (a) at the minimum winter temperature of 5°C. c. Discuss the implications of these results on backwash operations for plants that experience a large seasonal variation in water temperature.
Chapter2: Loads On Structures
Section: Chapter Questions
Problem 1P
Related questions
Question
Question 7.7
Transcribed Image Text:2.2
14.5
0.65
4.1
7 Rapid Granular Filtration
d. Design conditions: vp = 25 m/h, media = anthracite, ES = 1.50
mm, max available head = 3m (adapted from pilot results for
Portland, Oregon's Bull Run water supply).
Time to
Breakthrough,
Initial
Head Loss,
Media
Head Loss When
Breakthrough
Occurred, m
D
Depth,
Filter
m
m
2.0
2.3
2.5
3.0
41
49
55
0.43
0.51
0.51
0.63
1.8
2.0
2.5
2.9
3
4
65
7-7
A monomedia anthracite filter has an effective size of 1.0 mm and
media density of 1650 kg/m³.
a. Calculate backwash rate to get a 25 percent expansion at the
design summer temperature of 25°C.
b. Calculate the expansion that occurs at the backwash rate deter-
mined in part (a) at the minimum winter temperature of 5°C.
c. Discuss the implications of these results on backwash operations
for plants that experience a large seasonal variation in water
temperature.
7-8
Calculate the largest sand particle (specific gravity = 2.65) that would
be removed from a filter during backwashing if the backwash rate is
45 m/h and the water temperature is 15°C.
Akgiray, Ö., and Saatçi, A. M. (2001) "A New Look at Filter Backwash Hydraulics,"
Water Sci. Technol. Water Supply, 1, 2, 65–72.
Amirtharajah, A. (1988) "Some Theoretical and Conceptual Views of Filtration,"
J. AWWA, 80, 12, 36–46.
Amirtharajah, A. (1993) "Optimum Backwashing of Filters with Air Scour:
A Review," Water Sci. Technol., 27, 10, 195-211.
Clark, M. M. (2009) Transport Modeling for Environmental Engineers and Scientists, 2nd
ed., Wiley-Interscience, Hoboken, NJ.
Crittenden. J. C., Trussell, R. R., Hand, D. W., Howe, K. J., and Tchobanoglous, G.
(2012) MWH's Water Treatment: Principles and Design, 3rd ed., Wiley, Hoboken, NJ.
Ergun, S. (1952) "Fluid Flow through Packed Columns," Chem. Eng. Prog., 48, 2,
89-94.
Ives, K. J. (1967) “Deep Filters," Filtration and Separation, 4, 3/4, 125–135.
Iwasaki, T. (1937) "Some Notes on Sand Filtration," J. AWWA, 29, 10, 1592–1602.
-234
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 5 steps
Recommended textbooks for you
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 (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
Traffic and Highway Engineering
Civil Engineering
ISBN:
9781305156241
Author:
Garber, Nicholas J.
Publisher:
Cengage Learning