a) P(X > 680) = P(Z > (680-600)/45) = P(Z>1.7778) = 0.03772
b) Value = Mean + Z10% SD = 600 + 1.282*45 = 657.69
c)
d)
1. The total flow at a wastewater-treatment plant is on average 600 m' /day with a...
The total flow entering a wastewater treatment plant is constant at 9,000 m^3/day. The flow is evenly split between Three biological reactors that are installed in parallel. Each of the reactors hasd a volume of 750,000 L. What is the hydraulic retention time (in hours) of each reactor? 1. (Ipts) The total flow entering a wastewater treatment plant is constant at 9,000 m/day. The flow is evenly split between three biological reactors that are installed in parallel. Each of the...
A wastewater treatment plant receives an average of 4.5 MGD of wastewater flow. Two rectangular primary clarifiers operating in parallel will treat the flow. If the overflow rate is 700 gpd/ft2 and the depth of the clarifier is 10 ft, Determine: a) the dimensions of each clarifier assuming L:W ratio = 5:1. b) the detention time of each clarifier (in days).
The Penn State Wastewater Treatment Plant experiences high fluctuations in flow rate throughout the year. During football games, the flowrate and BOD concentration entering the treatment plant increases, while in the summer when the majority of students are gone, the flow rate decreases a. Describe what would happen to the treatment efficiency during each of these events (football games and summer). Justify your answer by describing how the F/M ratio and the mean cell residence time (ec) will change during...
primary clarifier is to be designed for a municipal wastewater treatment plant with a flow of 4160 m/d and peak flow during the day of 3.10 times the average hourly flow. Pertinent data are: peak overflow rate 73.3 m/d.-m2, maximum peak weir loading 373 m3/d-m, and minimum tank depth 2.13 m. Determine: A. The clarifier diameter B. The side water deptlh C. The peak weir loading. Is it acceptable? D. The percent suspended solids removal on the basis of the...
A community wastewater treatment plant has an average discharge flow rate of 3.5 MGD (million gal per day) with a BOD5 concentration of 28 mg/L. The stream receiving the discharge has a flow rate of 12 ft3 /s and a BOD5 of 11 mg/L. You may assume k = 0.18 d -1 . a. Determine the BOD5 immediately after the streams have mixed. b. Determine the BODu for the stream after the streams have mixed. c. Downstream of the discharge...
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...
9.9 Design an aerated grit chamber system to treat a 1-day sustained peak hourly flow of 1.6 m/s with an average flow of 0.65 m/s. See Table 9.4 for design guidance. Determine: a. The grit chamber volume (assuming two chambers will be used) b. The dimensions of the two grit chambers. c. The average hydraulic retention time in each grit chamber. d. Air requirements, assuming 0.20 m of air per m length of tank per minute. e. The quantity of...
The average American gets a haircut every 43 days. Is the average larger for college students? The data below shows the results of a survey of 12 college students asking them how many days elapse between haircuts. Assume that the distribution of the population is normal. 45, 53, 39, 46, 37, 47, 43, 40, 35, 53, 39, 55 What can be concluded at the the α = 0.10 level of significance level of significance? A) For this study, we should...
Do shoppers at the mall spend less money on average the day after Thanksgiving compared to the day after Christmas? The 57 randomly surveyed shoppers on the day after Thanksgiving spent an average of $143. Their standard deviation was $30. The 53 randomly surveyed shoppers on the day after Christmas spent an average of $138. Their standard deviation was $36. What can be concluded at the αα = 0.10 level of significance? Assuming Equal Variances For this study, we should...
1. The design flow for a water treatment plant (WTP) is 1 MGD (3.8x103 m'/d). The rapid mixing tank will have a mechanical mixer and the average alum dosage will be 30 mg/L theoretical mean hydraulic detention time of the tank will be 1 minute. Determine the following: a) the quantity of alum needed on a daily basis in kg/d, b) the dimensions of the tank in meters for a tank with equal length, width, and dept c) the power...