In: Civil Engineering
Primary clarifier effluent was analyzed for solids content by an analytical laboratory. A 250-mL sample of the effluent was filtered through a laboratory (1 micrometer) filter. A 241-mL sample of the filtrate contained 89 mg of salts as dissolved solids (Residue 1). Solid residue from the filtration was dried overnight at 105 deg C and weighed 37 mg (Residue 2). What were the concentrations of total dissolved solids, total suspended solids, and total solids in the primary clarifier effluent?
| Water Sample Volume (mL) |
250 |
| Filtrate Volume (mL) |
241 |
| Filtrate Residue (Residue 1, mg) |
89 |
| Filter Residue (Residue 2, mg) |
37 |
In: Civil Engineering
describe the examples of treatment sludges for solar drying, thermal drying and combustion applications in summary with their technical details.
In: Civil Engineering
Part 1
Select all answers that are correct
Group of answer choices
a. Sulphate, silica, carbonation and chloride can cause chemical damage to concrete.
b. Concrete is a mixture of Portland cement, water, aggregates and admixtures.
c. Concrete can be damaged by fire, freezing weather, aggregate expansion, bacterial corrosion and leaching.
d. None of the answers is correct.
e. Concrete has been around for thousands of years.
Part 2
Chemical admixtures:
Group of answer choices
a. can increase the curing rate.
b. can slow the hydration rate.
c. Are the largest component found in concrete. Concrete is mostly admixture.
d. Cement is an example of an admixture.
e. Include accelerators, retarders, corrosion inhibitors, workability agents, bonding agents.
In: Civil Engineering
A 60-acre medium-density residential property experienced a peak storm event that produced 5.7 inches of rainfall over a 330-minute period. The property has a slope of 3.1% and has sandy soil characteristics. What is the peak runoff flow rate in units of ft3/s?
In: Civil Engineering
What could be the implication(s) in the following case?
1 The feed solids concentration too low and insufficient biogas generated during anaerobic digestion.
2 Lack of proper lubrication of the gearbox mechanism of the digester
3 Allowing air into the digester when withdrawing of supernatant phase
4 Sludge pumping (primary sedimentation) is too low.
.5 Sludge pumping (primary sedimentation) is too high
6 Accumulation of debris on mechanical bar screens during
preliminary treatment.
In: Civil Engineering
A large 20-story steel structure is planned for an office building the Denver Metropolitan. The exploration program revealed that foundation soil comprises of 25-foot clay with undrained shear strength of 1,000 psf overlying a thick stiff clay shale with the undrained shear strength of 3,000 psf. To avoid construction noise, the architect selected 3-ft diameter drilled shaft foundation. The drilled shafts are socketed 15 feet in the stiff clay shale. Calculate:
a. The ultimate capacity of the drilled shaft.
b. Estimate the total structural dead load.
c. Estimate the office building life load.
d. At a factor of safety of 2,5, how many drilled shafts would be required?
Note: When you suspect some missing information, please make reasonable assumption(s) and process with your solution. Clearly show why assumption(s) is needed.
In: Civil Engineering
A community has two waste sources S1 and S2 having option to
dispose waste at either
landfill LF1 at $4/tonne, or LF2 at $6/tonne. S1 and S2 generate
waste at 150 tonnes/week and 300
tonnes/week, respectively, and transportation costs are $8/tonne
(S1 to LF1), $7/tonne (S1 to LF2),
$6/tonne (S2 to LF1), and $5/tonne (S2 to LF2). (A) (2 points) At
which landfills should S1 and S2 dispose
the wastes to minimize total cost of transportation and disposal?
(B) (4 points) What are the minimum
costs of transportation and disposal ($/week) for S1, S2, and total
community? (C) (4 points) What are
the minimum transportation costs ($/week) for S1, S2, and total
community?
In: Civil Engineering
An emergency response unit is preparing for a hurricane (and the potential for a prolonged power outage). As part of their preparation, they are filling Yeti Tundra 110 coolers with ice. The inside dimensions of each cooler is approximately 15 inches high, eleven inches wide and 30 inches long. Based on these dimensions, the volume capacity of each cooler is 4,900 cubic inches and the external surface area of the four sides plus top and bottom is given as 1,800 square inches. The sides, top and bottom of the Yeti coolers is made of 2-inch polyurethane with an R-value of 14 (ft2-°F-hr/BTU).
If each cooler is being filled with 84 pounds of ice and the average outside temperature is expected to be 81°F, how many days will it take for all of the ice to melt? (For your calculations, assume that the temperature inside the coolers is 32°F and that the coolers remain closed.)
In: Civil Engineering
Discuss the differences between Newtonian and non-Newtonian fluids in terms of shear stress vs. shear rate characteristics.
In: Civil Engineering
How does an interior designer blend lighting design into overall design?
In: Civil Engineering
How does an interior designer blend lighting design into overall design?
In: Civil Engineering
Give three advantages and three disadvantages of source separation of waste for recycling
In: Civil Engineering
Engineering Ethics
In: Civil Engineering
Describe the operation of a MRF (Material Recovery Facility) to process Municipal Solid Waste (Refuse) for the recycling of PETE, HDPE; Glass and Metals. Include a flow diagram of the process.
In: Civil Engineering