Home Water and Bottled Water

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Home Water and Bottled Water
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Water Filters
Carbon
Ceramic Filtration
Ion Exchange
3-stage water filtration
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Carbon Block Water Filters
Inlet
Purified Water
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Activated Carbon
Activation by heating
3 grams activated carbon
Extremely porous with high surface area 500 m2/g
Surface areas as high as 1500 m2/g are achievable
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Activated Carbon
Filtration
Particle size removal gt 0.5 microns
Bacteria range in size from 0.2-2 microns in
width and up to 1-10 microns in length
Giardia and Cryptosporidium parasites removed,
also
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Activated Carbon
Absorption spontaneous movement of primarily
organic contaminants from water
to carbon matrix.
Carbon matrix
Pesticides, volatile organics
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Treatment Residuals
Trihalomethanes (organics)
Trichloromethane(chloroform) CHCl3
Dibromochloromethane CHClBr2
Bromodichloromethane CHCl2Br
Tribromomethane (bromoform) CHBr3
All are carcinogens Formed as a byproduct of
disinfection with chlorine Effectively removed by
carbon block filtration
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Chlorine Removal
OCI-
Hypochlorite
2OCI- C ? 2Cl- CO2
OCI-
2Cl- CO2
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Polyester mesh (particulates) Iodine-impregnated
beads (bacteria) Activated Carbon (parasites,
iodine, organics)
185 gallons of water,
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Metals
Metals are not effectively removed by carbon
filtration
They can be removed by ion exchange resins and by
reverse osmosis processes
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Ion Exchange Filters
Metals
Pb2, Hg2
Na
Na
Na
Na
Na
Pb2
Na
Na
Na
Neg. Charge
Neg charge
Na
Na
Na
Na
Na
Hg2
Na
Na
Na
Na
Na
Na
Na
Na
Finite Capacity
4 Na
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Water Softeners
Hardness Ions
Ca2, Mg2
Na
Na
Na
Na
Na
Mg2
Na
Na
Na
Neg. Charge
Neg charge
Na
Na
Na
Na
Na
Ca2
Na
Na
Na
Na
Na
Na
Na
Na
Calcium Deposits
4 Na
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Reverse Osmosis
Extremely Effective
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Osmosis
Net movement of water
Salt molecule
Spontaneous movement of water
No salts
Membrane permeable to Water only
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Reverse Osmosis
Purified water
pressure
Membrane permeable to Water only
Contaminants to drain
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Drawbacks
Energy intensive Saline/contaminant
by-product inefficient high volume reject water
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Activated Carbon Filters
Tastes Odors
Chlorine
Organic chemicals
2OCI- C ? 2Cl- CO2
Ion Exchange Resins
Removal of charged Contaminants (metals)
Reverse Osmosis
Sediments, viruses, bacteria, dissolved solutes
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What about Bottled Water?
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The global consumption of bottled water reached
41 billion gallons in 2004, up 57 percent in
just five years.
In 2007, US consumers purchased more than 33
billion liters of bottled water
More than 5 trillion gallons of bottled water is
shipped internationally each year.
According to a NRDC study, U.S. consumers paid
between 240 and 10,000 times more per gallon for
bottled water than for tap water
For the price of one bottle of Evian, Americans
can receive 1,000 gallons of tap water
Supplying Americans with plastic water bottles
for one year consumes more than 47 million
gallons of oil
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Whats the Source?
More than 25 percent of bottled water comes from
a public source.
National Resource Defense Council
If water is packaged as "purified" or "drinking
water," It likely originated from a municipal
water supply, and unless the water has been
substantially altered, it must state on the
label that the water comes from a municipal 
source.
Both Aquafina (Pepsi) and Dasani (Coca-Cola)
originate from municipal water systems
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Artesian water, groundwater, spring water, well
water - water from an underground aquifer which
may or may not be treated. Well water and
artesian water are tapped through a well. Spring
water is collected as it flows spontaneously to
the surface or via a borehole. Ground water can
be either.
Distilled water - steam from boiling water is
re-condensed and bottled. Distilling water kills
microbes and removes waters natural minerals
Drinking water water intended for human
consumption and sealed in bottles or other
containers with no ingredients except that it may
optionally contain safe and suitable
disinfectants. Fluoride may be added within
limitations
Purified water - water that originates from any
source but has been treated to meet the U.S.
Pharmacopeia definition of purified water.
Purified water is essentially free of all
chemicals. Reverse osmosis is often used.
Other terms used on the label about the source,
such as glacier water or mountain water," are
not regulated standards of identity and may not
indicate that the water is necessarily from a
pristine area
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Is it safe?
Most bottled water appears to be safe. (NRDC
independent testing of 1000 bottles)
EPA sets standards for tap water provided by
public water systems the Food and Drug
Administration sets bottled water standards
based on EPA's tap water standards
Most bottled water is treated more than tap
water however, some is treated less or not
treated at all .
About 22 percent of the brands tested by NRDC
contained, in at least one sample, some chemical
contaminant
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PET
polyethylene terephthalate (PET) bottles
phthalates
known to disrupt testosterone and other hormones,
can leach into bottled water overtime.
One study found that water that had been stored
for 10 weeks in plastic bottles contained
phthalates, suggesting that the chemicals could
be coming from the bottle, the plastic cap or the
liner
It also appears possible that some as-yet
unidentified chemicals in plastics have the
potential to interfere with estrogen and other
reproductive hormones
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Antimony
Royal Society of Chemistry Publication
The study stressed that amounts of antimony were
well below official recommended levels. But it
also discovered that the levels almost doubled
when the bottles were stored for three months
The study collected 48 brands of water in PET
bottles from its source in the ground at a German
bottling plant. The water had 4 ppt of antimony
before being bottled, the contents of a new
bottle had 360 ppt and one opened three months
later had 700 ppt.
The U.S. EPA has established 6.0 parts per
billion (ppb) as a safe level
The health effects of antimony ingestion are not
well known
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Where are all the old bottles?
88 of water bottles are not recycled
In 2005, 2 million tons of plastic water bottles
were not recycled
In 2006, 2 billion half-liter bottles of water
were shipped to U.S. ports
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Your grades will be posted this afternoon
There are
28 sets of Lecture Questions (100 pts) 4 Homework
Assignments (100pts) 21 sets of Bonus Questions
(20 pts) 4 total Exams (200 pts. Each)
Your lowest exam grade of the 4 will be dropped