Environmental Engineering Reference
In-Depth Information
12.85 What is the hydraulic loading (in gpd/ft
2
) for each filter at a 0.75:1.0
recirculation ratio?
12.86 What is the organic loading (in lb BOD per 1000 ft
3
) for each filter
at a 0.80:1.0 recirculation ratio?
12.87 What chemical is commonly added to a lagoon to increase avail-
able nitrate?
12.88 What chemical is normally required in the operation of a gravity
belt thickener?
12.89 What two chemicals can be added to anaerobic digesters to
increase alkalinity?
12.90 Name three main parts of the trickling filter, and give the pur-
poses of each part.
12.91 Name three classifications of trickling filters, and identify the
classification that produces the highest quality effluent.
Use the following information for Questions 12.92 through 12.94:
rBC influent
Flow = 8.40 MGD
Suspended solids = 150 mg/L
BOD
5
= 190 mg/L
rBC design
Number of stages = 8
Media area, stage 1 = 240,000 ft
2
Media area, stage 2 = 210,000 ft
2
Media area, stages 3-8 = 160,000 ft
2
(each)
k
factor = 0.55
Hydraulic loading = 7.1 gpd/ft
2
Soluble BOD organic loading = 6.5 lb BOD/1000 ft
2
12.92 What is the hydraulic loading in gpd/ft
2
?
12.93 What is the total organic loading (in lb BOD/day/1000 ft
2
of
media)?
12.94 What is the soluble BOD organic loading (in lb BOD/day/1000 ft
2
of media)?
12.95 Name the two chemicals responsible for the majority of inorganic
odors in wastewater treatment.
12.96 Describe the process occurring in the rotating biological contac-
tor process.
12.97 What makes the RBC process similar to the trickling filter?
12.98 Describe the appearance of the slime when the RBC is operating
properly. What happens if the RBC is exposed to a wastewater
containing high amounts of sulfur?
12.99 What do we call the slime that grows on a trickling filter?