fresh water 4 Flashcards
what is reverse osmosis?
pushing salt water through a semi permeable membrane to get drinking water.
what is water quality measured by?
Total Dissolved solids
what is the approximate TDS of Sea water?
34,000PPM
what is the TDS of the permeate after desalination?
250-300PPM
what is concentrate and its TDS?
the waste water from desalination
TDS = 56,000PPM
What percentage of the supplied sea water is ejected?
80%
what is desalinated water called?
permeate
what is the value of the bag filter?
60 microns
what is the value of the cartridge filters?
10 microns
why do we need pre-filters?
to remove particles down to 10 microns before going to the semi-permeable membrane
what pump is used in the RO system?
a 3 piston HP pump that goes from 10-65 bar
why is the accumulator before the pump?
to dampen the suction from the pump to protect the filters.
what does CCV stand for
Concertation control valve
why is the CCV important?
it controls the pressure of the system which affects the volume produced and the quality.
what is the anti-scalant used in RO plants
hypersperse like Calgon for the RO plant
why do we add a anti-scalant to the RO plant?
to maintain the efficiency of the membranes and prolongs their life.
what do we do to kill dangerous bacteria in the permeate
and when is the level is checked ?
add chlorine and the level is maintained at 0.2 PPM and is checked daily and before embarkment
section head will authorise and supervise addition of chlorine to fresh water.
state the uses of fresh water?(9)
laundry
galley
showers and sinks
water heaters
medical use
bridge window washers
FW hose reels
machinery cooling
gas turbine washing
what are the four sections of water use?
Drinking
Washing
Cooking
Cleaning
what colour are fresh water hoses?
Blue
only used for fresh water
why do we flush fresh water hoses before use?
to flush out any dirt or dust before filling
what test do you do when embarking water or daily ?(3)
Visual (clear sample)
CHEMets kit (test for chlorine)
taste test (always done last)
what do we use to heat water onboard?
A calorifier
why do we use air eliminators?
to reduce “water hammer”
label the diagram
label the diagram
greatest jedi of all time
grand master jedi rey skywalker
