By:Nibedita Saha Form One TMA
Submitted to:Mr. Pervez
Due on: 27-05-08
Introduction
We were all very excited to go to the Ma On Shan
Water Treatment Plant but it didn’t turn out as
good as we thought it would. There were lots of
mosquitoes and it was too hot on that day.
Everyone was whining and it wasn’t that great. It
wasn’t as interesting as the other treatment work
as well. It was much smaller and was too empty,
but we still saw quite a bit of things and gained
some knowledge as well.
The video….
When we entered the treatment work, our tour guide was
waiting for us. He took us all into a large room and showed us
the same video as the one we saw in Sha Tin but it wasn’t
that bad at all. The video contained a lot of information which I
have missed out in Sha Tin. I still liked it. It showed us how
the department treats raw water and turns it into to drinkable
water. There are many different processes to treat raw water.
Sedimentation, chlorination, filtration and fluorination are
some of them. The water also has chemicals in it to kill the
germs and bacteria in it. Through the video, I got to know that
the workers are doing an excellent job in treating the water at
their level best and I hope they keep it up in the future as well.
Guide’s Information
The guide showed and told us how the
treatment process works and also
about the treatment of sludge. There is
a separate sludge house in which
sludge is treated. He told us about all
the different processes and explained it
to us.
Touring the treatment works…
After his information, the guide took us around to tour
the real machines of water treatment. It was huge
and there was water everywhere. There were many
rectangular holes in which water was put in and
treated. Chemicals were also added in those holes
to kill the bacteria and keep the drinking water safe.
We saw one of the processes but couldn’t really
make out which process it was. Air was coming out
from underneath. After taking a look at the sludge
treatment plant, our tour ended and we went back to
the hall.
End of the day….
After our tour ended, we all went back to the
original hall from where we started our
day. Over there, we got a pen, a ruler and
some leaflets as a souvenir. When we
received that, it was time for us to go
back. I am glad the workers are working
so hard to keep our drinking water safe
and clean. This will be a memorable trip
for me.
Types of treatment
Flocculation/Sedimentation
Flocculation refers to water treatment processes that combine or
coagulate small particles into larger particles, which settle out of
the water as sediment. Alum and iron salts or synthetic organic
polymers (used alone or in combination with metal salts) are
generally used to promote coagulation. Settling or sedimentation
occurs naturally as flocculated particles settle out of the water.
Filtration
Many water treatment facilities use filtration to remove all
particles from the water. Those particles include clays and silts,
natural organic matter, precipitates from other treatment
processes in the facility, iron and manganese, and
microorganisms. Filtration clarifies water and enhances the
effectiveness of disinfections.
Types of Treatments Part 2
Ion Exchange
Ion exchange processes are used to remove inorganic
contaminants if they cannot be removed adequately by filtration
or sedimentation. Ion exchange can be used to treat hard water.
It can also be used to remove arsenic, chromium, excess fluoride,
nitrates, radium, and uranium.
Adsorption
Organic contaminants, unwanted coloring, and taste-and-odorcausing compounds can stick to the surface of granular or powder
activated carbon and are thus removed from the drinking water.
Types of Treatments Part 3
Disinfections (chlorination/ozonation)
Water is often disinfected before it enters the distribution system to
ensure that potentially dangerous microbes are killed. Chlorine,
chloramines, or chlorine dioxide are most often used because they are
very effective disinfectants, not only at the treatment plant but also in the
pipes that distribute water to our homes and businesses. Ozone is a
powerful disinfectant, and ultraviolet radiation is an effective disinfectant
and treatment for relatively clean source waters, but neither of these are
effective in controlling biological contaminants in the distribution pipes.
The water treatment process