The town of Pittsburgh discharges 0.126 m3/s of treated wastewater into Cherry Creek. The BOD5 of the wastewater is 34 mg/L. Cherry Creek has a 10-year, 7-day low flow of 0.126 m3/s. Upstream of the wastewater outfall from Pittsburgh, the BOD5 is 1.2 mg/L. The BOD rate constants k are 0.222 d21 and 0.090 d21 for the wastewater and creek respectively. The temperature of both the creek and the municipal wastewater is 208C. Calculate the initial ultimate BOD after mixing.

The town of Pittsburgh discharges 0.126 m3/s of treated wastewater into Cherry Creek. The BOD5 of the wastewater is 34 mg/L. Cherry Creek has a 10-year, 7-day low flow of 0.126 m3/s. Upstream of the wastewater outfall from Pittsburgh, the BOD5 is 1.2 mg/L. The BOD rate constants k are 0.222 d21 and 0.090 d21 for the wastewater and creek respectively. The temperature of both the creek and the municipal wastewater is 208C. Calculate the initial ultimate BOD after mixing.

Sustainable Energy

2nd Edition

ISBN:9781337551663

Author:DUNLAP, Richard A.

Publisher:DUNLAP, Richard A.

Chapter14: Ocean Thermal Energy Conversion And Ocean Salinity Gradient Energy

Section: Chapter Questions

Problem 14P

See similar textbooks

Similar questions

The City of Smyrna discharges 0.16 m3/s of treated wastewater into Chattahoochee River. The BOD5 for the wastewater is 30 mg/L. The river has a 10-year, 7-day low flow of 0.16 m3/s. Upstream of the wastewater outfall from Smyrna, the BOD5 is 3.2 mg/L. The BOD rate constants k are 0.202 d-1 and 0.085 d-1 for the wastewater and creek respectively. The temperature of both the creek and the municipal wastewater is 20oC. Calculate the initial ultimate BOD after mixing
A tannery with a wastewater flow of 0.011 m3/s and a BOD5 of 590 mg/L discharges into the Cattaraugus Creek (Nemerow, 1974). The creek has a 10-year, 7-day low flow of 1.7 m3/s. Upstream of the tannery, the BOD5 of the creek is 0.6 mg/L. The BOD rate constants k are 0.115 d21 for the tannery and 3.7 d21 for the creek. The temperature of both the creek and the tannery wastewater is 208C. Calculate the initial ultimate BOD after mixing. Answers: LoTannery 5 1,349.2 mg/L, LoCreek 5 0.6 mg/L, La 5 9.27 or 9 mg/L
Poorly treated municipal wastewater is discharged to a stream. The river flow rate upstream of the discharge point is Qus = 8.7 cubic meters per second. The discharge occurs at a flow of Qd = 0.9 cubic meters per second and has a BOD concentration of 50 mg/L. Assuming that the upstream BOD concentration is negligible. (a) What is the BOD concentration just downstream of the discharge point, after mixing? (b) If the stream has a cross-sectional area of 10 square meters, what would the BOD concentration be 50 km downstream? BOD is removed with a first-order decay rate constant equal to 0.20/day.
A stream with a flow of 1.7 m3/s and BOD 3.4 mg/l is saturated with DO (9.27 mg/l at 20oC). It receives a treated effluent discharge from a cocoa processing factory of BOD 6780 kg/day and DO of 5.0 mg/l. The BOD of the stream immediately after mixing is 7.6 mg/l. The DO at a point 36 km downstream is 7.20 mg/l. The average velocity of the stream flow is 0.2 m/s. Determine the flow and the BOD in mg/l of the treated effluent discharged from the cocoa processing factory into the stream. Assume the temperature is 20oC throughout, k1 for effluent/water mixture is 0.1/day, k2 for stream is 0.4/day.
You are constructing a sewage lagoon with a 3,100 m3/day inlet/outlet flow rate. You must attain a BOD outflow load of 12 mg/L given a BOD inlet load of 26 mg/L. BOD has a half-life of 2.4 days.What volume is needed for the lagoon and how long would it take for the output BOD concentration to reach 1 ppm if freshwater started to replace the wastewater that was previously entering the lagoon?
A small industrial plant discharges wastewater into a stream. The plant discharge has a flow rate of 0.2 m3/s and a BODu concentration of 40 mg/L. The stream receiving the discharge has a flow rate of 1.3 m3/s and a BODu of 6 mg/L. Downstream of the discharge point, the velocity in the stream is 0.15 m/s. Assuming no other sources of BOD enter the stream, what is the BODu remaining in the stream 10 km downstream of the plant discharge? Use k = 0.23 day-1.
You are building a wastewater lagoon with an inlet/outlet flow rate of 3,100 m3/day. The BOD inlet load is 26 mg/L and you need to achieve 12 mg/L at the outlet. The half-life of BOD is 2.4 days. What is the volume required for the lagoon? If the wastewater stopped entering the lagoon and was replaced by freshwater, how long would it take for the outlet BOD concentration to reach 1 ppm?
A wastewater treatment plant serves a city with a total population of 50000. The total service area for the treatment plant is 100 km2. The wastewater flow is 300 L/cap.d. During the wet weather conditions, the expected infiltration/inflow for the city is 3800 L/Ha.d. Estimate the peak flow for this treatment plant (m3/d).
A wastewater treatment plant discharges of effluent into a stream. Just upstream from the discharge point, the stream has an ultimate BOD of 5 mg/L.Assuming a cross-sectional area for the stream equal to 100 m2, what ultimate BOD (in mg/L) would you expect to find at a point of 15,000 m downstream? Wastewater Flow: 1 m3/secBOD (ultimate): 40 mg/LRiver Flow: 10 m3/secDeoxygeneation constant kd: 0.22 day-1
Assume that DLSUD lake is 100m2 and its average height is 5ft. Wastewater that flows into the lake are the following: Food square kitchen waste 7 m3/sec; Total Dissolved Solids (TDS) is 25,000 mg/L which operates 8hrs per day CIH 5m3 /hr kitchen waste; TDS is 20mg/L which operates 4hrs per day PCH 20m3 /day diluted laboratory waste ; TDS = 40mg/L (1)Determine the volumetric flow rate of the lake water can still accommodate prior to rainfall.
Question 4. An industrial process produces a by-product compound ‘X’ which exceeds the sewer use limit. Therefore, before the wastewater can be discharged to the sewer, the concentration of ‘X’ must be reduced to below 30 mg C/L. The industrial wastewater, with a concentration of 1780 mg C/L, flows through a long series of channels before reaching the treatment reactor. The long series of channels can be modelled as a PFR with a volume of 23 m3 and the treatment reactor can be modelled as a CSTR with a volume of 15 m3. The compound ‘X’ naturally degrades in the series of channels before the treatment reactor with a reaction rate constant of 0.75 mg/(L·min). In the treatment reactor the addition of chemicals and catalysts cause compound ‘X’ to degrade according to second order kinetics described with a reaction rate constant of 0.015 L/(mg·min). a) Derive the appropriate HRT equations for the PFR channels and the CSTR treatment reactor (state all assumptions and show all work). b) Does…
ENVIRONMENTAL ENGINEERING-WATER POLLUTION: The ultimate BOD of a river just below a sewage outfall is 50.0 mg/L, and the DO is at the saturation values of 10.0 mg/L. The deoxygenation rate coefficient, kd is 0.30/day, and the reaeration coefficient, kr is 0.90/day. The river is flowing at a speed of 48 miles per day. The only source of BOD on this river is this single outfall. FIND: The critical distance downstream at which DO is a minimum. The minimum DO. If a wastewater treatment plant is to be built, what fraction of BOD would have to be removed from the sewage to assure a minimum of 5.0 mg/L everywhere downstream?