An aerated lagoon (a sewage treatment pond that is mixed with air) is being proposed for a small lake com- munity in northern Wisconsin. The lagoon must be designed for the summer population but will operate year-round. The winter population is about half of the summer population. Based on these design assump- tions, the volume of the proposed lagoon is 3420 m³. The daily volume of sewage in the winter is estimated to be 300 m³. In January, the temperature of the lagoon drops to 0°C but it is not yet frozen. If the temperature of the wastewater flowing into the lagoon is 15°C, estimate the temperature of the lagoon at the end of a day. Assume the lagoon is completely mixed and that there are no losses to the atmosphere or the lagoon walls or floor. Also assume that the sewage has a density of 1000 kg m and a specific heat of 4.186 kJ kg K-¹

An aerated lagoon (a sewage treatment pond that is mixed with air) is being proposed for a small lake com- munity in northern Wisconsin. The lagoon must be designed for the summer population but will operate year-round. The winter population is about half of the summer population. Based on these design assump- tions, the volume of the proposed lagoon is 3420 m³. The daily volume of sewage in the winter is estimated to be 300 m³. In January, the temperature of the lagoon drops to 0°C but it is not yet frozen. If the temperature of the wastewater flowing into the lagoon is 15°C, estimate the temperature of the lagoon at the end of a day. Assume the lagoon is completely mixed and that there are no losses to the atmosphere or the lagoon walls or floor. Also assume that the sewage has a density of 1000 kg m and a specific heat of 4.186 kJ kg K-¹

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

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