The Providence news. (Providence [R.I.]) 1891-1906, 1894-05-18

Pawtuxet water forced through three
media of filtration in 60 different
and distinct machines, and
coming out OF each at the rate
OF 166 gallons per minute absolutely
devoid of color, free from suspended mai
ter, and with 80 per cent. reduction of
bacteria is the advantage which will be Sc
cured for consummers if the filtration
commission succeeds in getting the city
to contract for the orrison- Jewell filter.
II is the one that the commission wants,
the one that Commissioner of Public
Works smith, City Engineer
Shed and Superintendent of Health
Chapin all heartily approve OF and
endorse as being the best they have
examined during an investigate
more thorough than any city
has ever made along the same
lines. They have authorized to expend
100000, which is not enough, but Just
how much more is needed is as vet
a secret between the commission and The
Morrison-Jewell Company.
III the system Is agreed upon the con-
struction work will practically all be
done by the Rhode Island Locomotive
Works. so that a city concern will derive
a good deal OF benefit and the city will
have what 1t needs by November /, this
year.
As to the filter itself. The house viii
be a brick structure 36Sx50 feet, with an
engine house for the new Worthington en-
gine 50x60 feet with stack 100 feet i'm
height. A single filter, there are 90 OF
them all alike, Is q steel cylinder II II. 8 in.
in diameter and 10 feet high. A large
eliptical pipe runs across the bottom,
into this and at right angles
with it run 46 brass pipes along the upper
surface of which are screwed 500 circular
screens of aluminium bronze, placed about
two inches apart, and the entire bot
q N xrtfh IN ali
masonry around the pipes up to level
with the face of the screens, making a fat
surface with thousands of minute per-
forations grouped in the 500 two-inch
circles. Above this is placed a four
inch layer of pure white machine crushed
quartz from selected Long Island pebbles
and then comes the principal filter me-
dium, layer OF feet s inches OF fine
crushed quartz, and the water percolates
through the two layers and the screens,
flows out into a 4S-inch conduit at the
rate of 166 gallons per minute and goes to
the reservoir by gravity.
The original supply for the filters comes
from the river through Il now 9s=1nch
main, from that into 20 10 inch !
pipes, each one leading to q battery !
of three filters and finally !
through the individual pipes of six inches |
each. That's all there is 10 the filter |
so far as purifying tie water is |
a day, and the washing process is |
as simple as it is Ingenious. The supply |
from the feed pipe is shut of and the dow |
Is reversed, the water being pumped back /
and up through the screens at the
rate of 1000 gallons per minute and the
velocity of the 500 streams is sufficient to
raise the mass of the two quartz layers and |
keeping the thousands of particles in
and rapid motion while the
action of the rushing water is supple
nented by what is called the agitating
apparatus consisting of 81 steel
axes working in the crush
ng stone and moving in
circles at the rate of II revolu-
ions per minute. The water goes out
through a sewer connection four feet
bove the bottom of the cylinder,
aking with it ell the dirt that
he quartz has retained during the "a
lours.
The washing of a cylinder requires five
minutes.
The filter is the invention OF O. II. jew
IL of Chicago, andS. l.. Morrison of New
Iork.
1t is now in public use in 20 different
tiles.