A waste treatment pond is operated at a depth of 6 feet. The volume of the pond is 60 ac-ft. If the flow to the pond is 3.5 ac-ft per day, what is the detention time in days ?
The influent of a primary clarifier has a BOD content of 300 mg/L.
If the clarifier effluent is 100 mg/L, what is the BOD removal efficiency of the primary clarifier ?
A rotating biological contactor (RBC) treats a flow of 3.5 MGD.
The manufacturing data indicate that the RBC has a surface area of 600000 sq. ft. What is the hydraulic loading rate on the RBC ?
The daily flow to a trickling filter is 5 MGD. If the BOD concentration
of the trickling filter influent is 200 mg/L, how many kg of BOD enter the trickling filter daily ?
An industry generates 20000 m3 of wastewater daily. A circular
primary clarifier is to be designed has an average detention time of 3 hours and an average overflow rate of 15 m3 per day per square meter. What should the dimension of the clarifier be ?
BOD（mg / L）=（D1-D2） / P
D1：稀释后水样之初始溶氧（mg / L）
D2：稀释后水样经 20 ℃ 恒温培养箱培养 5 天之溶氧（mg / L）
P=【水样体积（mL）】 / 【稀释后水样之最终体积（mL）】