GATE-ES SERIES Water-wastewater-treatment-and-management
Sludge Generation Processing And Disposal Methods
2 previous year questions.
Volume: 2 Ques
Yield: Medium
High-Yield Trend
2
2021 Chapter Questions 2 MCQs
01
PYQ 2021
medium
water-wastewater-treatment-and-management ID: gate-es-
A sewage treatment plant (STP) receives sewage at a flow rate of 20000 m per day. The sewage has 200 mg/L of suspended solids. Assume 60% suspended solids are removed in the primary clarifier. The underflow (i.e. sludge) removed from the clarifier contains 5% solids (by weight).
The daily volume of the sludge generated will be ________ m per day.
Assume sludge density = 1000 kg/m .
The daily volume of the sludge generated will be ________ m per day.
Assume sludge density = 1000 kg/m .
1
48
2
80
3
480
4
800
02
PYQ 2021
medium
water-wastewater-treatment-and-management ID: gate-es-
A 10 million litres per day (MLD) sewage treatment plant (STP) is based on the Activated Sludge Process (ASP). First, the sewage undergoes primary treatment and the resulting treated sewage has BOD of 140 mg/L concentration. This is further passed through a 1500 m capacity aeration tank (in ASP), where the mixed liquor volatile suspended solids (MLVSS) concentration is maintained at 3000 mg/L. The concentration of BOD of the treated sewage is 5 mg/L. The Food to Microorganisms ratio (F/M) of the ASP is _______ day (rounded off to two decimal places).