Q4:Design rectangular primary sedimentation tank to remove 30% of BOD from the total an equivalent load...
Design rectangular primary sedimentation tank to remove 60% of SS and 30% of BOD from the total an equivalent load of influent BOD and SS = 700 kg/day when the maximum expected flow is 8000 m3/day and the detention time is 2.5 hr. (take L:W = 3:1). Then estimate: 1- The quantity of the sludge that is removed (assume moisture content of sludge (m.c) = 90%). 2. The effluent concentrations of BOD and SS.
A wastewater treatment plant that treats wastewater to secondary treatment standards uses a primary sedimentation process followed by conventional activated sludge process composed of covered aeration tanks and secondary clarifiers. You are asked to calculate the different operation parameters to make sure that the system is operated within normal process ranges listed in the reference tables below. Table 5-20 Typical design information for primary sedimentation tanks U.S. customary units Item Unit Range Typical Primary sedimentation tanks followed by secondary treatment...
:A wastewater treatment plant consisted of a primary sedimentation tank and two stages of trickling filter received flow 44L/Sec , the BOD concentration in raw sewage =440 mg/L , 30% BOD removed in the primary sedimentation tank, volume of filter (first stage )=826000L, volume of filter (second stage)=2563000L, recirculation rate =0.5 in second tank while no recirculation in first tank. Determine the following: 1-The effluent concentration of BOD in each unit. 2-Treatment efficiency of each unit. 3-Treatment efficiency of plant....
A wastewater treatment plant, which serves a population of 300,000 people, receives an average daily volume of 24 million gallons per day (MGD) at an average influent 5-day biochemical oxygen demand concentration of 200 mgBODs/L and an average influent total suspended solids concentration of 220 mgTSS/L. The plant operates a primary sedimentation process that remove 65% of the incoming TSS and 35% of the incoming BOD %. This process is followed by a secondary treatment process before discharge to the...
You are hired to design a rectangular sedimentation tank (length to width ratio = 3:1 and detention time ~ 2 h) for a new water treatment plant (flow rate: 0.04 m/s; temperature: 20 ). Suspended particles can be removed when the overflow rate is higher than the settling velocities of particles. You have finished characterizing the influent particles (assuming all of them are spherical) and obtained the following results: Particle diameter (m) Particle density (kg/m) Percentile 50 1.4 x 10...
You are hired to design a rectangular sedimentation tank (length to width ratio = 3:1 and detention time ~ 2 h) for a new water treatment plant (flow rate: 0.04 m3/s; temperature: 20 ℃). Suspended particles can be removed when the overflow rate is higher than the settling velocities of particles. You have finished characterizing the influent particles (assuming all of them are spherical) and obtained the following results: Particle diameter (μm) Particle density (kg/m3) Percentile ≥ 50 ≥ 1.4...
You are hired to design a rectangular sedimentation tank (length to width ratio = 3:1 and detention time ~ 2 h) for a new water treatment plant (flow rate: 0.04 m3/s; temperature: 20 ℃). Suspended particles can be removed when the overflow rate is higher than the settling velocities of particles. You have finished characterizing the influent particles (assuming all of them are spherical) and obtained the following results: Particle diameter (m) Particle density (kg/m3) Percentile 50 1.4 x 103...
Problem 2 (20 points) You are hired to design a rectangular sedimentation tank (length to width ratio = 3:1 and detention time 2 h) for a new water treatment plant (flow rate: 0.04 m/s; temperature: 20 °C). Suspended particles can be removed when the overflow rate is higher than the settling velocities of particles. You have finished characterizing the influent particles (assuming all of them are spherical) and obtained the following results: Percentile Particle diameter (um) > 50 > 60...
A complete-mix activated sludge system is used to treat municipal wastewater after primary sedimentation at 20 °C with MLVSS concentration of 2000 g/m3. The discharge standard for soluble BOD, concentration in the effluent is 0.5 g/m. The characteristics of the primary influent are: flow Q -2000 m'/d, soluble BOD -200 g/m3, Using these data and the kinetic coefficients in following, determine 1. Theoretical solids retention time (SRT) in unit of days 2. Pk vss in unit of kg VSS/d 3....
Situation (note: Problem 2 is not linked with Problem 1): Assuming the design flow rate of raw wastewater to be treated is 20 MGD in the design year, the dissolved BODs is 380 mg/L, and SS is 360 mg/L. The wastewater generated by the sludge treatment process is about 4 MGD with the dissolved BODs being 1800 mg/L, and SS being 1200 mg/L, and will be returned to the wet well in the pumping station at the beginning of the...