Which of the following are physical characteristics of municipal sewage commonly assessed during preliminary examination?
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ATurbidity
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BColour
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COdour
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DTemperature
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EAll of the above
Answer
Correct Answer: All of the above
Explanation
Introduction / Context:Characterizing sewage involves physical, chemical, and biological parameters. Physical characteristics provide quick diagnostic indicators of condition and treatment needs.
Given Data / Assumptions:
- Municipal sewage at plant inlet.
- Standard physical observations: appearance, smell, and temperature.
Concept / Approach:Physical assessments help identify septicity (odour), solids load (turbidity), dye/industrial influence (colour), and process performance implications (temperature affects reaction rates and viscosity).
Step-by-Step Solution:Confirm each parameter is a recognized physical characteristic: turbidity, colour, odour, temperature.Select the consolidated option covering all such characteristics.
Verification / Alternative check:Introductory wastewater texts list these as standard physical indicators alongside settleable solids observations (e.g., Imhoff cone for settleables).
Why Other Options Are Wrong:
- Single-parameter choices omit others that are equally standard.
Common Pitfalls:Confusing physical with chemical parameters (e.g., pH, alkalinity, BOD are not physical).
Final Answer:All of the above