All flashcards
Flashcard 1: Which gas is commonly produced in anaerobic digesters?
Answer: Methane. Produced when organic matter decomposes without oxygen.
Flashcard 2: State one advantage of using anaerobic digestion.
Answer: Produces biogas for energy. Methane can be captured and used as renewable fuel.
Flashcard 3: Identify a common issue with sludge management.
Answer: Odor control. Decomposing organic matter produces unpleasant smells.
Flashcard 4: What is typically measured to assess the effectiveness of disinfection?
Answer: Coliform bacteria levels. Indicates presence of disease-causing microorganisms.
Flashcard 5: What is the first step in primary sewage treatment?
Answer: Screening. Bars or mesh remove large objects from wastewater.
Flashcard 6: Identify a method used for odor control in sewage treatment.
Answer: Carbon filters. Activated carbon absorbs odorous compounds from air.
Flashcard 7: Identify the main goal of primary sewage treatment.
Answer: To remove large solids from wastewater. Physical settling removes debris and suspended particles.
Flashcard 8: Identify a benefit of using UV light for disinfection.
Answer: No chemical residues left in water. No toxic chemical compounds remain after treatment.
Flashcard 9: Which treatment stage typically involves aeration tanks?
Answer: Secondary treatment. Aeration provides oxygen for biological waste breakdown.
Flashcard 10: What is a disadvantage of using chlorine for disinfection?
Answer: Formation of harmful by-products. Can create toxic chlorinated compounds like trihalomethanes.
Flashcard 11: Which term describes the measure of organic pollution in water?
Answer: Biochemical Oxygen Demand (BOD). Measures oxygen needed to decompose organic matter.
Flashcard 12: Which organisms are utilized in secondary treatment?
Answer: Microorganisms (bacteria and protozoa). These organisms consume organic waste in biological treatment.
Flashcard 13: Identify the main component of sewage that causes eutrophication.
Answer: Nutrients such as nitrogen and phosphorus. Excess nutrients stimulate algae growth and oxygen depletion.
Flashcard 14: What is the purpose of scum removal in sewage treatment?
Answer: To remove floating fats and oils. Grease and oil float and must be skimmed off.
Flashcard 15: Name a biological process used in secondary treatment.
Answer: Trickling filters or activated sludge. Both use microorganisms to consume organic pollutants.
Flashcard 16: Which treatment process uses microorganisms to degrade waste?
Answer: Biological treatment. Living organisms consume and break down pollutants naturally.
Flashcard 17: What is one environmental benefit of using biosolids?
Answer: Can be used as fertilizer. Provides nutrients for crops while recycling waste.
Flashcard 18: State one advantage of using anaerobic digestion.
Answer: Produces biogas for energy. Methane can be captured and used as renewable fuel.
Flashcard 19: What are the primary stages of sewage treatment?
Answer: Primary, secondary, and tertiary treatment. These represent physical, biological, and advanced treatment processes.
Flashcard 20: What does a high BOD indicate about water quality?
Answer: High levels of organic pollution. More organic matter requires more oxygen for decomposition.
Flashcard 21: Identify a key indicator of nutrient pollution in water.
Answer: High nitrate and phosphate levels. These nutrients cause algal blooms and oxygen depletion.
Flashcard 22: What is the function of a bar screen in sewage treatment?
Answer: To remove large solid objects. Prevents large items from entering treatment systems.
Flashcard 23: What is the main goal of sludge stabilization?
Answer: To reduce pathogens and odors. Biological and chemical processes reduce health risks.
Flashcard 24: Identify a common issue with sludge management.
Answer: Odor control. Decomposing organic matter produces unpleasant smells.
Flashcard 25: Which process follows coagulation in sewage treatment?
Answer: Flocculation. Gentle mixing forms larger particles from coagulated matter.
Flashcard 26: What is the purpose of using coagulants in sewage treatment?
Answer: To clump fine particles for easier removal. Chemicals bind small particles into larger, settleable flocs.
Flashcard 27: What is removed during the screening process?
Answer: Large debris. Prevents clogging and damage to treatment equipment.
Flashcard 28: What is the purpose of disinfection in sewage treatment?
Answer: To kill pathogens in treated water. Prevents disease transmission from contaminated water.
Flashcard 29: Identify a common by-product of sewage treatment.
Answer: Biosolids. Treated sludge can be beneficially reused in agriculture.
Flashcard 30: What does the term 'effluent' refer to in sewage treatment?
Answer: Treated wastewater. The clean water discharged after treatment processes.