The record-union., 1891-05-27
HOW PARIS DOES TT.

pumped 10 hight OF thirty feet before
the discharge upon the land. All the
solids are retained in tanks. and only the
fluids sent to the farm. The solids are
used as fertilizers. The cost to Paris is
100000 francs, the income 10000 francs.
The etfluent at this farm is as clear as
spring water. Vegetables are raised on the
sewage land that go into the city market
Berlin has two large sewage farms of
: 900 and $4,000 acres; S20,O00,000 have
been expended upon the works. The
sewage is pumped to hight of sixty
five feet to reach the land. The COM
blned sewer system is in use. The sew
age is stored in immense basins, and the
liquids are lost mainly by sipage into the
earth. 1t requires month for basin to
thus drain, though the earth is subpiped.
Dantzic, with 100000 people, sends its
sewage to a farm, 100000 gallons day.
The farm pays profit of $4,000 a year to
the city. The land is waste of sand that
cost nothing.
PURIFYING SEWAGE IN ENGLAND.
The English parishes of Merton, Nor
don and Mitcham drain to a sewage farm
used first for tanks. Two outfalI sewers
deliver it by gravitation. The tanks are
divided by partitions with dip boards in
the first that catch ali floating matter.
The sewage then passes over one and I'M
der another of several partitions, thus
agltating it, and then through two per-
forated walls and a bed of coke to filter it
and to remove all solid matter. When
the liquid has passed out, the sludge is
discharged into a well over which is a
machine for grinding and dropping lime
into 1t. Then it passes to a second well,
where it is thoroughly mixed. 1t passes
to a third we'll and is then pumped 10 air
tight tanks and forced into presses and
comes outin solidified cakes that are used
for tertiiiZing. In the meantime the fluids
run on into trenches in land set apart for
that purpose. Under each is a drain pipe
of brick, and these discharge the etl!uent
into the river. "A million gallons are
daily treated in two beds of land alter
nately, each having rest of four days.
The works cost 100000, and accomm0-
date the sewage daily OF 1856 people to
each acre of land. Some crops are raised
on the land-roots and rye grass.
CHEMICAL PRECIPITATION.
The Scott process OF chemical precipita-
ton is used at Burnley Population, 81 ,020.
Two million gallons of sewage are treated
daily. There are sewage sewers, and sur
face or drainage sewers. Ten per cent
of the houses have water closets. The
sewage flows to the works in an open
trench. Into it pipe discharges milk of
lime. and salmon ladder thoroughly
mixes the composition. 1t then runs into
settling tanks, six i'll number. In these
the precipitation takes place, and the Clar-
flied liquid IS drawn Off at the top. The
sludge is then collected and run through
q pug mill and spread on a drying floor,
beneath which arc furnaces. 1t Is then
put into coke kilns and burned for thirty
six hours. The cinder is ground, and
makes q fair substitute for Portland ce-
ment. Ii has a tensile strength Of $50
pounds per square inch, after being i'm
mersed in water for week. The etliu
ent from the works is very clear. The
works cost SD, 600, and the city pays the
company operating them -, $50 a year.
Bradford has precipitation works. Pop
ulation, 100000. The sewage runs to four
tanks, is screened Ell route of all floating
matter. and then is charged with milk Of
lime and agitated by flow through mar
row openings in part. It then passes
to thirty-four precipitating tanks, and
when settled, the clarified liquor Is
drawn off and drained into a brook. The
siudge is pumped into tanks and dried.
The precipitant is milk OF lime alone.
The works cost 53e0,G and the operating
expenses are SO, 900 q year, but the men
receive only 50 80 a week. The two-sewer
system is in use.
Leeds, with 300 600 population, has pre-
cipltaCiOn works and the combined sewer
system. The treatment is more elaborate
ciple. The etliuent is very clear and de-
priyed OF all harmful matter. The sludge
is given away to farmers after it is dried.
It costs the city S30,0CJ q year to operate
the system with lime at s. 16 ton.
The Legion Precipitation Works serve
a population of 100. They cost SIC. 000
and the operating cost is $1,000 year on
the average. The precipitatant is made
OF crude sulphate of alumina, prOtOsul-
hot ~ irnn y 7
pounds of chemicals for every million
gallons OF sewage. The claim is that it is
a cheaper process than that of using lime
The sludge Is dried in cakes and sold to
farmers. The etiluent is discharged over
seven acres grown to os;ers. All the water
closets connect with the sewers.
At BIRMINGHAM.
Birmingham has precipitation works
and irrigation combined. Population,
40, 900. Two sewer systems are in use, one
for sewage and one Tor water drainage.
The precipitant is introduced into the
sewers above the works a third Of mile.
There are 10000 house connections and
10000 water closets connected with the
sewers. Some 500 gallons Of sew
AGE are treated daily. There are three
large and sixteen small precipitation
tanks. The sludge Is shoVeied out, dried,
and sent to farms where it is spaded into
million gallons Of sewage. also, SEQ
acres Of land are used aud 70Jmore were to
be added at the time OF Mr.. Aliens visit.
To these lands the sewage passes after
going through tho tanks. The ground is
all underdraiEcd. The efIluent is clear,
harmless. and runs into the river Tame.
The works cost $3.50, 900, and the precipita-
ton costs the city $4,000 year. The in
come from the tanks is 500 a year: from
.L,,f "a. q of n
farm operation is SS7 800 a year. It is not
necessary to give the results of inyestiga-
ton at Atherton, Aldershot. Ruby and
other places.
HISTORY OF SEWAGE DISPOSAL.
Early in the century the sewage pollu-
ton of the rivers of England attracted
attention. 1t became apparent that some
system OF publication must be adopted,
or towns and cities must cease TO low
sewage into the streams. Commissions
were appointed by cities, towns and the
general Government, and investigation
began After great deal of experiment.
ing, in which il was found that the solids
can be extracted and the effluent rendered
comparatively clean, some works were
erected. But the early ones were far
from satisfactory. AS in all things else
man had to learn by bitter experience.
Filteration was then added To precipita-
IlOD Win III SuECGs'S. DlJllilli9i nam lhel
tried subsiding tanks, so arranged as to
keep the fluids in agitation ana TO send
the efiuent into the river Rea. Still the
etlluent was very disagreeable and a
nuisance TO residents below on the
stream. Coventry then tried subSiding
tanks and filter of coarse gravel. The
resulting sludge sold at good price, but
the efIiuent was so bad that the works had
to be abandoned.
THEY WOULD NOT DO.
These and other experiences proved
that simple subsistence and liberation
would not do. Then irrigation and
sewage farms were tried, and the two
processes are in use 10 this day. The two
are fairly successful, and a good efiluent