The secondary clarifier in the secondary treatment stageHas a uniform distribution of solids throughout its depthFurther removes organic matter in the influent sewage by settlementAllows for the separation of the biomass from the treated wastewaterIs optional in the activated sludge process because the bioreactor treats the sewage to sufficient effluentstandards

A secondary clarifier is a settling chamber that removes flocculated organic matter from the…

The secondary clarifier in the secondary treatment stage Has a uniform distribution of solids throughout its depth Further removes organic matter in the influent sewage by se Allows for the separation of the biomass from the treated wa

The secondary clarifier in the secondary treatment stage Has a uniform distribution of solids throughout its depth Further removes organic matter in the influent sewage by se Allows for the separation of the biomass from the treated wa

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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A rapidly mixed tank consists of a treatment unit used to disinfect a solution. The solution enters the 2000 m3 tank at a rate of 0.4 m3/s. The pollutant contains 7.94 CFU per liter and has no 0 mg/l of chlorine. The treatment unit uses a stock solution containing 750 mg/L which is released a rate that will cause the chlorine concentration in the tank to be 2 mg/L. The chlorine reacts with the water in such a way that it is depleted at a rate (in mg/L-h) given by rcl = ( -0.45 / h) CCl. When exposed to chlorine, the bacteria die off at a rate (in cells/L-s) given by:a) Calculate the required flow rate in L/s of the stock solution when the system is operating at steady state, including a schematic of the system.b) Determine the bacterial concentration (in CFU/L) thar should be expected in the effluent from the tank?
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