Sewege Treatment Plant

Question 1

What is Black Water

Answer 1

Drainage and waste from:
WCs
WC Scuppers
Urinals
Medical Compartments

Question 2

What is Grey Water

Answer 2

Drainage doesnt require treatment to discharge

Question 3

Where does Grey Water come from?

Answer 3

Dishwashers
Launderies
Bathrooms
Galleys
Sinks

Question 4

0-4NM

Answer 4

IMO approved sewege treatment plant

Question 5

4-12NM

Answer 5

IMO approved system to disinfect discharge (chlorine)

Question 6

12NM

Answer 6

No treatment needed

Question 7

Advantages of having STP on board

Answer 7

Simplify pipe runs

Heads and Bathrooms lower in deck

Heads and Bathrooms used in drydock

Operate in anti pollution area

Reduce ship side openings

Question 8

Aerobic Digestion

Answer 8

Air supply is bubbled through slurry to encourage digestion from microorganisms

Question 9

Anaerobic Digestion

Answer 9

If aerobic fails, micro organisms die, produce hydrogen sulphide

Question 10

How would you detect anaerobic digestion at low levels

Answer 10

The smell (rotten eggs)

Question 11

What causes anaerobic digestion on biological stp

Answer 11

Flushing wrong things down the toilet that cant go through the stp

Question 12

Purpose of coarse screen

Answer 12

Removes large matter that has bypassed the macerator

Question 13

Purpose of primary

Answer 13

Air lifts the slurry from the aeration compartment into settlement hopper

Question 14

Purpose of secondary air lift

Answer 14

Thick matter sinks to the bottom, and goes through the sludge return back into aeration compartment to be more diluted

Question 15

Purpose of aeration diffuser

Answer 15

Sens air from aeration compartment to begin aeration digestion

Question 16

0.03ppm

Answer 16

Odor

Question 17

150-400ppm

Answer 17

Less of smell, dizziness, nausea

Question 18

1000+ppm

Answer 18

Immediate unconciousness
Seconds until death

Question 19

Hazards associated with raw sewege

Answer 19

Hepatitis
Typhoid
Gastro Enteritis

Question 20

Hazards associated with STP

Answer 20

Chlorine
H2S
Methane

Question 21

How does the collect hold and transfer tanks

Answer 21

1. Vaccums suck slurry into collection tanks via soil in pipes
2. Collection Tank can hold slurry for up to a day
3. Transfer pump moves slurry into holding tanks
4. Holding Tanks can hold slurry for up to 12 days
5. Recirculating pump moves slurry through the ejector, back into the holding tanks, ready to be discharged
6. The ejector prevents anaerobic respiration, and works with bernoullis theorem
7. Slurry is discharged through High Discharge at port, or Low Discharge at sea

Question 22

VPS

Answer 22

Vaccum Pump System

Question 23

What does VPS consist of

Answer 23

Hoses, Manifolds, Diesel Pumps