topic 6

Question 1

Coliform are

Answer 1

faculative aerobes, gram neg, non spore forming rods that ferment lactose with gas formation

-live in animal gut
signal fecal contamination
-enterobacter, ecoli

Question 2

waste water deginition

Answer 2

liquid effluents derviced from domestic sewage or industrial sourcesb that annot be dumped into lakies

two types:
1) industrial:
comes from plastic, petrochemical, industries

2)Domestic:
seweage, “grey water” bathing, cookijg, food processing

Question 3

what are the goals of wastewater treatements

Answer 3

-reduce organc matter
-reduce inorganic nutrient lebels
remove pathogens

Question 4

what are the contaminants in waste water

Answer 4

Suspended Solids: hair, feces, plant fibers

Biodegradeable organics: fats, proteins, oils

Pathogens: Salmonella , Vibrio Cyptosporidium. viruses

Priority Pollutnts: phenol. benzene

Refractory organics: gasoline

Heavy metals: Mercury, lead

Dissolved inorganics: phosphates, nitrates

Question 5

Wastewater treatment stages

Answer 5

1) Primary Treatments: Screening adn Sedimentary:
large chunks removed, liquid left to settle in a tank, the sediments go to bottom and move to aerated tank while sludge continues on

2) Secondart Treatments:
a)Trickling Filter
b) Aeration Tank (activated Alusdge)
c)Disinfection
d) Sludge digestion
basically use microbes to take out organic and inorganic components

3) Tertiary Treatments: Main goal is to remove inorganics such as nitrogen and phosphate by using Bioreactors, precipitation, filteration or chlorination (Physiochemical or bioilogical process)

Question 6

What microorh is presentin the biofilm of wastewater treatment

Answer 6

1) Bacteria: Zoogloea ramigera, Pseudomonas, Archomobacter, flavobacterium, MAINLY HETEROTROPHS bc we want it to eat the organic matter, nitrosomonas and nitrobacter, methanogens and sulfate reducing bacteria
2) FUngi, protozoa, nematodes, rotifiers

Question 7

Flocs

Answer 7

Apart of aeration tank (activated sludge) which is secondary waste water treatment

-it is substrata that bacteria can attach to (so it can coonsume organic matter Mineralization or biotransform it)

MAIN THING: adsoprtion of soluble organic matter to flocs, some mineralizztion