The Wilson Wastewater Treatment Plant currently provides primary treatment for a flow rate of 2500 m³/day. The effluent from the primary tank has a soluble BOD₅= 240 mg/L. You need to design an activated sludge treatment to update the plant. The secondary effluent standards to meet are 25.0 mg/L BOD₅ total (suspended and soluble BOD) and 30 mg/L suspended solids. Use the following assumptions:

• Target soluble BOD₅ in the effluent of the secondary treatment is 2.5 mg/L.
• Growth constants can be estimated as K_s=145 mg/L BOD₅; k_d=0.025 d^-1; m_m=8 d^-1; Y=0.8 mg VSS/mg BOD₅ removed.
• The designed MLVSS is 3,000 mg/L.
• The settler is designed to achieve 12,000 mg SS/L in the settled sludge.
• The MLVSS fraction of MLSS is expected to be 0.7

1. (4 pts) Estimate the sludge age (q_c) to achieve the target effluent criteri
2. (6 pts) Estimate the hydraulic retention time and volume of the aeration tank (in m³).
3. (4 pts) Compute the F/M ratio.
4. (4 pts) Estimate the observed yield in the system (mg VSS/mg BOD₅ removed)
5. (4 pts) Calculate the net waste activated sludge produced (kg VSS/day).
6. (4 pts) Calculate the cell solids (VSS) in the effluent in mg/L based on the designed suspended solids target for the effluent.
7. (4 pts) Calculate the cell solids (VSS) in the settled sludge in mg/L based on the designed SS concentration in the secondary settler.
8. (4 pts) Determine the sludge waste flow rate (m³/day) using sludge age. Do not ignore biomass in the effluent.
9. (4 pts) Determine the sludge return flow rate (m³/day). Do not ignore biomass in the effluent.

A cantilever of circular solid cross section is fixed at one end and carries a concentrated load P at the free end. The diameter at the free end is 200mm and increases uniformly to 400 mm at the fixed end over a length of 2m. At what distance from the free will the bending stresses in the cantilever be maximum? Also calculate the value of the maximum bending stress if the concentrated load P=300 KN

(a) 1.23 m, 12.32 MPa

(b) 1.5 m, 11.23 MPa

(c) 1.0 m, 11.32 MPa

(d) 1.33 m, 13.42 MPa

Block B is initially at rest. Then block A slides on the smooth surface to the right and collides with block B with a velocity vAvA. Consider three following collision cases where: i) elastic impact; ii ) perfectly plastic impact; iii ) e = 0.5. Just after the collision, rank these three cases where the relative velocitiy of B with respect to A is from largest to smallest magnitude.

- When subcritical flow goes over a step down, does the kinetic energy increase, decrease or remain constant?

- You have subcritical flow going through a channel constriction that does not influence upstream water levels. If the critical depth is observed in the constriction, the minimum specific discharge is passing through the constriction

True or false?

- Subcritical flow encounters a step up transition that is smaller than the maximum step height. Does the specific energy:

- In supercritical flow that does not encounter a hydraulic structure, the upstream water is influenced by downstream conditions.

True or False?

Calculate the monthly average evaporation to occur from the surface of the water in open July, taking into account the following data for a lake,
£ using the Penman method.£
Latitude: 40.5 N.
Monthly Avg. Temperature: 21.3 C.
Real daylight hours: 9.8 hours
.2m wind speed: 145 km / h.
Albedo: 7%.
Relative Humidity: 55%

no sir it is homework I have to solve it by penman rules

#1 You are overseeing the plans for construction of a new highway. Someone proposes using cheaper, substandard materials to control/treat water flowing off the construction site. The water on the construction site contains measureable concentrations of sediments, oils from vehicles, heavy metals, and components of asphalt. A recreational lake is nearby and downgradient from the construction site. This is a substantial slope (10% grade) across the site.

Parts pertaining to #1:

a) LIST the three pillars of sustainability and EXPLAIN how this issue connects to each pillar.

b) Assuming you are a licensed engineer, what is your ethical obligation to the public AND other licensed engineers working on this job? [Your response should cover ethical obligations to both parties.]

Will like right away!!

3)Descriptive calls are given considerable weight when there are ambiguities.

True

False

4)

If a naturally created island is discovered in the middle of a navigable river in Texas, who can have the rights of ownership to this land?

1)List three of the seven exceptions to the plat requirements.

Design a square concrete column footing to support a 400-mm x 400-mm reinforced concrete column. The center of the column and footing must coincide. Loads: ???=350 ??, ???=480 ??, ???=100 ??−?, ???=130 ??−? Column Design Criteria: ??′=28 ???, ??=400??? Footing Design Criteria: ??′=28 ???, ??=400???, ??=180 ???,??=1.70 ?, ??=16 ??/?3,??=24 ??/?3, ??=25 ??, assume a thickness of the footing of 700 mm.

Design a square concrete column footing to support a 500-mm x 500-mm reinforced concrete column. The center of the column and footing must coincide.
Loads: ???=350 ??, ???=480 ??, ???=100 ??−?, ???=130 ??−?
Column Design Criteria: ??′=28 ???, ??=400???
Footing Design Criteria: ??′=28 ???, ??=400???, ??=175 ???,??=1.50 ?, ??=16 ??/?3,??=24 ??/?3, ??=20 ??, assume a thickness of the footing of 500 mm.

An ISA 90X60X8mm of steel of grade Fe410 is connected to a 12mm gusset plate and is used as a tension member design the weld if weld is to be provided on upper and lower edges of connected legs

An activated sludge system with recycle (CMFR) uses to treat primary effluent after sedimentation.Use the appropriate kinetic coefficients for the influent water characteristics to CMFR. Influent Characteristics: Flow = 1000 m3/day; bsCOD= 192 g/m3; nbVSS= 30 g/m3; inert inorganics= 10 g/m3

Aeration Tank Data: MLVSS = 2500; g/m3; SRT or θc = 6-day

Calculate:

1.- Fraction of Biomass in MLVSS

2.- Observed yield

a) gVSS/ g bs COD

b) gTSS/g bs COD

3.- Oxygen Requirement Kg/day

Compute the elevation of TP1 after correcting for “curvature and refraction” given:

“BM A” elevation = 595.00’ (NAVD 88)

BS (plus sight) rod reading on “BM A” = 7.00’ at a horizontal distance of 1,900'

FS (minus sight) rod reading on “TP1” = 1.00’ at a horizontal distance of 1,950'

Please put the final answer in feet.

For a small scale hydraulic power system, the elevation difference between the reservoir water surface and the pond water surface downstream of the reservoir is 20.35. The velocity of the water exhausting into the pond is 7 m/s, and the discharge through the system is 4 m³/s. The head loss due to friction in the penstock (inlet pipe to turbine, under very high pressure) is negligible. Find the power produced by the turbine in kilowatts. Assume specific weight of water is 9810 N/m³ and g = 9.81 m/s²

1. The annual precipitation measurements (Pi in cm) for M city, over a 20year period are shown in the following table. Determine the mean, standard deviation, and skew coefficient for this series.

2. Determine the mean, standard deviation, and skew coefficient for the log values of annual rainfall for M City, given in Problem 1. Also determine the mean precipitation (in cm) of the log-transformed data.

Please clarify each step of the solution.