Appendix VI – Bone Char Filter Construction
In
order to filter the maximal amount of fluoride and arsenic from tap water or
Silicade, the water must be adjusted to pH 4.8 with sodium bisulfate and then
filtered slowly (i.e. less than 400cc/min) through a bone char filled filter
cartridge and finally brought to pH 6.5 with sodium bicarbonate prior to
drinking. The flow should be bottom-to-top in order to flush most of the air
out of the bone char. The least expensive and most convenient way of constructing
such a filter is to purchase an Aquatic Life ion exchange cartridge filter with
quarter inch polyethylene tubing from Amazon. Pour out the ion exchange resin
and fill the empty filter cartridge with bone char. The filter can be held
vertically with two clamps attached to a lab stand (see figure 37). More details
are given below.
Figure
37 – Removing
fluoride and arsenic from one gallon of pH 4.8 tap water or Silicade being
syphoned through a bone char filter in series with a gravity-fed Brita pitcher
style filter
Cut
the polyethylene tubing into two different lengths and attach as indicated in
figure 37. Use the Brita filter and plastic insert sold with a Brita pitcher
style filter to catch the water flowing out of the bone char filter. Use two, one
gallon-sized plastic or glass containers. In order to maintain the syphon, one
container must be placed on a shelve that is higher than the exit of the
outflow tube on the bone char filter (see figure 37). The other container must
be topped with the Brita filter and be low enough to catch the outflow of the
bone char filter. Start the syphon by sucking on the outflow tube on the bone
char filter until water begins to flow.
How to Prepare and Refill the
Bone Char Filter
1.
Remove the threaded end-cap
from the Aqua Life filter cartridge and if new, pour out the resin for disposal
or if used, pour out the spent bone char for disposal while retaining the o-ring,
plastic disk, and two particle filters (i.e. top and bottom particle filters).
2.
Rinse the empty filter
cartridge and refill it with first the bottom particle filter and then the bone
char until the top particle filter sets gently on the bone char and the plastic
disk on top is flush with the top of the cartridge.
3.
Slide the o-ring on just
above the cartridge threads and screw on the top cap being careful to not cross
threads.
4.
Prepare pH 4.8 tap water or
Silcade with sodium bisulfate microprills from Loud Wolf sold by Amazon. Use a temperature compensated pH meter
($10-$20 from Amazon) and a set of Norpro measuring spoons, including “dash”
and “drop”. Try starting with one level “dash” of sodium bisulfate with
stirring per gallon and, if insufficient to lower to pH to 4.8, try adding one
level “drop” of sodium bisulfate with stirring at a time.
5.
Syphon one gallon of pH 4.8
tap water or Silicade through the filter flushing the filter and then leave the
filter filled with the pH 4.8 tap water or Silicade to soak the bone char for three
days prior to use as a fluoride and arsenic filter.
Bone Char Filter Performance
This
bone char filter will remove 72% of fluoride from 50 gallons of tap water or
Silicade containing 0.5ppm fluoride resulting in tap water or Silicade with
only 0.14ppm of fluoride. With distilled water
containing 1 ppm fluoride, 100% and 92% of the fluoride is removed after 25 and
50 gallons of tap water has been filtered, respectively. The fluoride capacity of this filter is 200mcg of fluoride per gram of
bone char in tap water or Silicade.
After filtering 50 gallons of
tap water or Silicade the bone char must be refilled. After filtering 75
gallons of tap water or Silicade, the bone char filter only removed 21% of the
fluoride595.
This
bone char filter will also remove approximately 60% of arsenic reducing arsenic
levels to below 10mcg/liter (10ppb)603 the maximum
contaminant level (MCL) of arsenic in drinking water in the U.S.
Details on Components of Bone
Char Filter
·
Bone char 20x60 mesh size can purchased in 6,
10, 25 and 50 lb. amounts from Charcoal House in Crawford, NE. 6 lbs. sells for $49.39 plus $20 shipping in
a gallon jar SKU C-541. Density of this bone char is 1.089gr/cc and is $7.90 for
a refill of this bone char filter. Call Charcoal House at 308-665-1566 as it is
not available online.
·
Aquatic Life DI
color changing mixed bed filter cartridge 2x2x12 inches with ¼” tubing fittings
and 284cc internal volume (1.625” dia, x 8.375” = 17.36 cubic inches) for
holding approximately 309grams (0.68 lbs.) of bone char. The cartridge can be
purchased from Amazon for approximately $20 and it will be shipped free by
Premium Aquatics. After receiving filter, empty and refill with bone char.
·
Polyethylene
tubing ¼ inch NSF certified for food use from PureSec/CCK 100 feet sold by
Amazon for approximately $20.
·
Cast iron ring stand
with acid resistant finish from American Educational Products sold by Amazon
for approximately $20.
·
Two 3-prong lab
clamps finger style from OESS sold by Amazon $13.45 each
Optional Suppliers of Bone Char
·
Bone char 20x60 mesh size
made at 800oC can be purchased in bulk from Ebonex Corporation in
Melvindale, MI, U.S.A. 313-388-0060 Cost per pound is $3.95 for the minimum
order of a 50lb. bag not including UPS shipping (for a list of international
distributors see: http://www.Ebonex.com)
·
Bone char 20x60
mesh size (e.g. 0.010” to 0.033”) can be purchased online by the pound at
Highwater Filters for $16/lb. (Kosher/ANSI 61 Certified). Highwater Filters is
in Colville, WA at 509-685-0933 Highwater Filters purchase their bone char from
the Charcoal House.
https://www.highwaterfilters.com/products/1-lb-bone-char-gac-20x60-mesh