An activated sludge treatment process uses a rectangular tank that can be modeled as two completely mixed reactors in series. The volume of the tank is 300 cubic meters (for modeling purposes 150 cubic meters each) and the flow rate into the system is 900 m3/day. The influent BOD concentration is 180 mg/L and the first order reaction rate coefficient is 0.5 hr-1.   What is the effluent concentration of BOD? If the Biomass Yield, Y is equal to 0.6 mg SS/mg of BOD metabolized, what is the rate of SS (biomass) production in the aeration tanks (mg/L-day)? If the post-secondary clarifier effluent SS concentration is 10 mg/L, the sludge recycling rate is 33%, and the waste sludge flow rate is 5 m3/day, what is the SS concentration in the waste sludge (hint: assume the system is at steady state and complete a mass balance)?  What is the sludge age?

Structural Analysis
6th Edition
ISBN:9781337630931
Author:KASSIMALI, Aslam.
Publisher:KASSIMALI, Aslam.
Chapter2: Loads On Structures
Section: Chapter Questions
Problem 1P
icon
Related questions
icon
Concept explainers
Question

An activated sludge treatment process uses a rectangular tank that can be modeled as two completely mixed reactors in series. The volume of the tank is 300 cubic meters (for modeling purposes 150 cubic meters each) and the flow rate into the system is 900 m3/day. The influent BOD concentration is 180 mg/L and the first order reaction rate coefficient is 0.5 hr-1.

 

  1. What is the effluent concentration of BOD?
  2. If the Biomass Yield, Y is equal to 0.6 mg SS/mg of BOD metabolized, what is the rate of SS (biomass) production in the aeration tanks (mg/L-day)?
  3. If the post-secondary clarifier effluent SS concentration is 10 mg/L, the sludge recycling rate is 33%, and the waste sludge flow rate is 5 m3/day, what is the SS concentration in the waste sludge (hint: assume the system is at steady state and complete a mass balance)?
  4.  What is the sludge age?
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps

Blurred answer
Knowledge Booster
Biological processes
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, civil-engineering and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Structural Analysis
Structural Analysis
Civil Engineering
ISBN:
9781337630931
Author:
KASSIMALI, Aslam.
Publisher:
Cengage,
Structural Analysis (10th Edition)
Structural Analysis (10th Edition)
Civil Engineering
ISBN:
9780134610672
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Principles of Foundation Engineering (MindTap Cou…
Principles of Foundation Engineering (MindTap Cou…
Civil Engineering
ISBN:
9781337705028
Author:
Braja M. Das, Nagaratnam Sivakugan
Publisher:
Cengage Learning
Fundamentals of Structural Analysis
Fundamentals of Structural Analysis
Civil Engineering
ISBN:
9780073398006
Author:
Kenneth M. Leet Emeritus, Chia-Ming Uang, Joel Lanning
Publisher:
McGraw-Hill Education
Sustainable Energy
Sustainable Energy
Civil Engineering
ISBN:
9781337551663
Author:
DUNLAP, Richard A.
Publisher:
Cengage,
Traffic and Highway Engineering
Traffic and Highway Engineering
Civil Engineering
ISBN:
9781305156241
Author:
Garber, Nicholas J.
Publisher:
Cengage Learning