3. A filter has been designed to have a run length of 48 hours while operating at a filtration rate of 12 m/h. The design backwash rate is 40 m/h, backwash duration is 15 min, and filter-to-waste duration is 10 min. The plant operator decides to clean the filters more thoroughly and backwashes at a rate of 55 m/h for 25 min. As a result, ripening takes longer and the filter-to-waste duration is 50 min. Calculate the UFRV, UBWV, UFWV and recover y (a) as designed and b) as operated. What is the percent increase in the volume of treated water lost as waste backwash and filter-to-waste water?

3. A filter has been designed to have a run length of 48 hours while operating at a filtration rate of 12 m/h. The design backwash rate is 40 m/h, backwash duration is 15 min, and filter-to-waste duration is 10 min. The plant operator decides to clean the filters more thoroughly and backwashes at a rate of 55 m/h for 25 min. As a result, ripening takes longer and the filter-to-waste duration is 50 min. Calculate the UFRV, UBWV, UFWV and recover y (a) as designed and b) as operated. What is the percent increase in the volume of treated water lost as waste backwash and filter-to-waste water?

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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PART B 1. The data are given as follows: Weight of evaporating dish: 53.5430 g Weight of evaporating dish and residue after drying at 103°C: 53.5760 g Weight of filter and residue after drying at 103°C: 1.5530 g Weight of filter and residue after ignition at 550°C: 1.5450 g Volume of sample filtered: 50 mL Volume of sample dried: 80 mL Determine the total solids, volatile suspended solids, suspended solids, fixed suspended solids and total dissolved solids. Assume 60% of suspended solids were loss on ignition.
The rate of eradicating microbes through chlorination process is 0.22/min when the wastewater is flowing at a rate of 36 m3/h. If the depth of chlorination tank is 1.6 m and the width is 1.2 m, determine the required length of the tank to achieve 98% removal.
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At a small water treatment plant which has 4 filters, the rates of filtration and backwashing are 200 m³/d/m² and 1000 m³/d/m² respectively. Backwashing is done for 15 min per day. The maturation, which occurs initially as the filter is put back into service after cleaning, takes 35 min. It is proposed to recover the water being wasted during backwashing and maturation. The percentage increase in the filtered water produced (up to two decimal places) would be
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As an operator of a wastewater treatment facility, you have learned that your plant runs well at an SRT (based on MLVSS (X) in the aeration basin) of 12 days. If today’s MLVSS (X) concentration is 2,700 mg/L and the RAS (Xr) concentration is 5,500 mg/L, how many L of sludge should you waste from the secondary clarifier today? Other design conditions: Average influent flow = 12,000 m3/d Influent soluble BOD = 150 mg/L Required effluent TSS = 30 mg/L Aeration tank Volume = 1,000 m3