Questions
9. The following data are given for an activated sludge process: BOD5 (influent) = 250 mg/L...

9. The following data are given for an activated sludge process: BOD5 (influent) = 250 mg/L (soluble) BOD5 (effluent) = 20 mg/L (soluble) MCRT = 10 days MLSS in the aeration tank = 2500 mg/L Concentration of SS in the recycle line = 10,000 mg/L Concentration of SS in the effluent = 30 mg/L (70% biodegradable) BOD5/BODu = 0.75, No nutrient limitations. Yield co-efficient, Y = 0.65 Endogenouse decay coefficient, kd = 0.06/day , Q=5MGD

Determine:
(a) Find soluble BOD5 (in mg/L) in the effluent, BOD5 treatment efficiency (in %) and overall efficiency (in %)
(b) Find hydraulic detention time (in hours) and the volume of tank (in MG).
(c) Yobs and biomass production (in lb VSS/day) (d) Qw (in MGD) when the wasting from the AT and from recycle line. (e) Recirculation ratio (f) Find Specific Utilization rate (U) and food to microorganism (F/M) ratio (g) Calculate volumetric loading rate (lb BOD5 /1000 ft3)

In: Civil Engineering

[HCM for Basic Freeway Segments] A six-lane freeway (three lanes in each direction) operates at the...

[HCM for Basic Freeway Segments] A six-lane freeway (three lanes in each direction) operates at the maximum service flow rate (MSF) of LOS D conditions during the peak hour with an observed demand volume of 3500 veh/h (one direction). The free flow speed (FFS) of the freeway is estimated to be 65 mi/h. The freeway is on rolling terrain and the traffic stream consists of passenger cars and buses only. The PHF is 0.85 and the traffic is all commuters. If a new busway was open next to this freeway and all buses were removed from the freeway, the new demand volume is 2354.55 (veh/h) for this freeway segment. Assume that car traffic remains the same.

What would be the LOS under the new demand volume? Note that this new demand volume now consists of passenger cars only as the buses were removed from this traffic stream. Assume that the freeway operates under ideal conditions (no incidents, work zones, or weather events).

In: Civil Engineering

Depth of flow at downstream of a hydraulic jump at a reservoir outlet is 7m. The...

Depth of flow at downstream of a hydraulic jump at a reservoir outlet is 7m. The downstream channel is rectengular with a bottom of 4m. The discharge rate is 135 m3/s and the change in elevation among all 3 cross-sections are negligible. Determine the height of sluice gate and depth of water in the reservoir at upstream of the sluice gate.

In: Civil Engineering

Explain how Civil Liberties and Civil Rights address global warming through carbon emissions (300 words).

Explain how Civil Liberties and Civil Rights address global warming through carbon emissions (300 words).

In: Civil Engineering

Explain the relation between Stiffness matrix and Maxwell-Betti reciprocal work theorem with an example

Explain the relation between Stiffness matrix and Maxwell-Betti reciprocal work theorem with an example

In: Civil Engineering

A Portland Cement Concrete (rigid) pavement is to be designed using AASHTO empirical design method. The...

A Portland Cement Concrete (rigid) pavement is to be designed using AASHTO empirical design method. The pavement should have an 8" granular sub-base having elastic modulus (Esb) of 50x103 psi. The resilient modulus of the subgrade is 5000 psi, and lying just 5 feet above rock strata (bed rock).

(a) Determine the design k value, assuming loss of support factor (LSF) of 2.

(b) Use the k value obtained from (a) to determine the thickness of the rigid pavement.  

Assume concrete elastic modulus (Ec) = 5 x 106 psi , Modulus of rupture (Sc) = 650 psi, load transfer factor J = 3.2, drainage coefficient Cd = 1.0, present serviceability loss ∆PSI = 4.2 — 2.5 = 1.7, reliability R = 95%, standard deviation So = 0.29, and total ESAL W18 = 5.1 x 106.

In: Civil Engineering

The vulnerability of soil types to a mechanical stress process (same intensity and magnitude) is different....

The vulnerability of soil types to a mechanical stress process (same intensity and magnitude) is different. Explain why.

In: Civil Engineering

Determine the location of the shear centre of the C-shaped rolled-steel beam cross-section C150x19.3 with respect...

Determine the location of the shear centre of the C-shaped rolled-steel beam cross-section C150x19.3 with respect to the centre of the web. Indicate whether it is to the left or right of the centre of the web. Assume the section to be thin walled and neglect the rounding of corners.

In: Civil Engineering

Sedimentation basins are employed both in filter plants for drinking water treatment and in municipal wastewater...

Sedimentation basins are employed both in filter plants for drinking water treatment and in municipal wastewater treatment plants. Briefly explain what solids are removed in each of these sedimentation basins.

In: Civil Engineering

A vertical curve is designed for 90 km/h and has an initial grade of + 2.5%...

A vertical curve is designed for 90 km/h and has an initial grade of + 2.5% and a final grade of -1.0%. The PVT is at station 3 + 480. It is known that a point on the curve at station 3 + 440 is at elevation 75 m. What is the stationing and elevation of the PVC? What is the stationing and elevation of the high point on the curve?

In: Civil Engineering

An equal-tangent crest vertical curve is designed for 100 km/h. The initial grade is +3.4% and...

An equal-tangent crest vertical curve is designed for 100 km/h. The initial grade is +3.4% and the final grade is negative. Draw the curve. What is the elevation difference between the PVC and the high point of the curve?

In: Civil Engineering

A vertical curve is designed for 75 km/h and has an initial grade of + 3.5%...

A vertical curve is designed for 75 km/h and has an initial grade of + 3.5% and a final grade of -2.0%. The PVT is at station 3 + 560. It is known that a point on the curve at station 3 + 520 is at elevation 85 m. What is the stationing and elevation of the PVC? What is the stationing and elevation of the high point on the curve?

In: Civil Engineering

i would really appreciated if answer this question quickly thank you all ! A vertical curve...

i would really appreciated if answer this question quickly thank you all !

A vertical curve is designed for 75 km/h and has an initial grade of + 3.5% and a final grade of -2.0%. The PVT is at station 3 + 560. It is known that a point on the curve at station 3 + 520 is at elevation 85 m. What is the stationing and elevation of the PVC? What is the stationing and elevation of the high point on the curve?

In: Civil Engineering

Think back to all of the ways we have learned to analyze structures by hand in...

Think back to all of the ways we have learned to analyze structures by hand in this class. Now recall the SAP2000 assignments and any other software program we may have used (excel, maybe Mathcad or MatLab). Using at least 10 sentences, discuss how technology is making it easier and making it harder to complete structural analysis tasks. In what way does technology present new challenges? What are some of the advantages and disadvantages?

In: Civil Engineering

1. a) If you were a consulting engineer and were submitting Turnkey tender on behalf of...

1. a) If you were a consulting engineer and were submitting Turnkey tender on behalf of a Turnkey Contractor, would you consider a conflict of interest between the role of a consulting engineer and contractor? Enlarge on the ethics of this subject. b) It is clear to you that an Engineer engaged in a particular project (implement at the taxpayer’s account) is not maintaining professional standards, i.e. professional competence and integrity are lacking. What would be your reaction? Will you report the above incident to the Board of Engineers, Malaysia or bring this to the attention of the client, or will you maintain silence and watch substandard work being completed? c) “Professional Engineer should be allowed to practice as consultants and as a contractor at the same time”. Do you agree with this statement? If so, give your reason objectively for supporting it; if not also give reasons for appeasing it.

The answer shall be about 1500 words.

In: Civil Engineering