Water Production

Question 1

What are some of the uses for Fresh Water?

Answer 1

-Drinking
-Washing
-Cooking
-Cleaning

Question 2

What services are provided by the Fresh Water System?

Answer 2

-Laundry
-Galley
-Showers and Sinks
-Water Heaters
-Medical Use
-Bridge Window Washers
-Fresh Water Hose Reals
-Machinery Cooling

Question 3

What is Osmosis?

Answer 3

The transfer of pure water through a semi-permeable membrane into salt water

Question 4

What is Reverse Osmosis?

Answer 4

Transfer of salt water through a semi-permeable membrane into pure water

Question 5

How is Water Purity measured?

Answer 5

Total Dissolved Solids (TDS)

Question 6

What is the TDS of Sea Water?

Answer 6

Approximately 34,000ppm

Question 7

What is the TDS of the water after desalination?

Answer 7

Between 250 and 300ppm

Question 8

How much of the supplied Sea Water is ejected?

Answer 8

Approximately 80%

Question 9

What is the desalinated water called?

Answer 9

Permeate, sometimes referred to as Made Water

Question 10

What is the waste water called after desalination?

Answer 10

Concentrate

Question 11

What filters do RO Plants use?

Answer 11

-Bag Filter
-Cartridge Filter

Question 12

What do Bag Filters filter down to?

Answer 12

60 Microns

Question 13

What do Cartridge Filters filter down to?

Answer 13

10 Microns

Question 14

What pump does an RO Plant use?

Answer 14

High Pressure, 3 Piston Positive Displacement Pump

Question 15

What is the pressure produced by the pump in an RO Plant?

Answer 15

65 Bar

Question 16

What separates the Made Water from the Rejected Water in an RO Plant?

Answer 16

Cushioned Membranes that have ultrasonically welded edges

Question 17

What does an Anti-Scalant Dosing Unit prevent?

Answer 17

Precipitation of calcium salts directly forming on the membrane surfaces

Question 18

What rate is Hypersperce applied?

Answer 18

5ppm

Question 19

What is the purpose of the Concentration Control Valve?

Answer 19

To control the back pressure of the sea water acting on the membrane cushions

Question 20

How does the Concentration Control Valve work?

Answer 20

-By closing the valve, the back pressure is increased and the amount of permeate is increased

-By opening the valve, the back pressure is reduced and reduces the amount of permeate

Question 21

Why can’t water contain Chlorine when is passes through an RO Plant?

Answer 21

It will cause irreversible damage to the membranes

Question 22

When is Chlorine added to the water?

Answer 22

After the membranes, in order to kill off any bacteria

Question 23

What is the maintained level of Chlorine in Made Water?

Answer 23

0.2ppm

Question 24

When should desalination not continue?

Answer 24

If the source of water is likely to be contaminated

Question 25

Who authorises the addition of Chlorine to the fresh water?

Answer 25

Section Head

Question 26

When does Fresh Water Testing take place?

Answer 26

Daily and prior to embarkation

Question 27

What are the different Fresh Water Tests?

Answer 27

-CHEMets
-Visual
-Taste

Question 28

What are Calorifiers used for?

Answer 28

To heat water on-board ship

Question 29

What is a symptom of air in the fresh water system?

Answer 29

‘Water Hammer’, which is a loud and repetitive banging noise inside the pipes

Question 30

What colour are Fresh Water hoses?

Answer 30

Blue

Question 31

What should you do before using a fresh water hose?

Answer 31

Flush it out with fresh water