Environmental Engineering Reference
In-Depth Information
inhumanity, environmental disruption, and resource wasting. The second is: from
the view point of the employer, work is in any case simply an item of cost, to be re-
duced by automation. From the view point of the workman, work is a disutility and
wages are a compensation for the sacrifice. The third is: modern economics does
not distinguish between renewable and non-renewable materials, as its very method
is to equalize and quantify everything by means of a money price. And the fourth
is: the ideal of industry is to eliminate the living factors, even including the human
factor, and to turn the productivity process over to machines.
In addition, Schumacher proposed an “Intermediate Technology”, later called
“Appropriate Technology”, which is defined as being cheap enough so that they
are accessible to everyone; suitable for small-scale application; and compatible
with man's need for creativity. What might such intermediate technologies be? I
would like to point to some technologies which may be included in the intermedi-
ate technology category. The first example is Rome concrete which has long-term
durability of more than 2000 years. It is composed of volcanic ash, hydrated lime
and water, and its strength is preserved by a geo-polymer reaction. Modern concrete
made of Portland cement has only 60 years of a durable period due to carbonation,
and it needs huge energy and emits large amounts of CO
2
in its production process.
In Cuba, Rome concrete is applied to building materials because of its low environ-
mental load as well as low cost. In Japan also, a kind of Rome concrete was applied
to the breakwater of Otaru Bay. This concrete includes volcanic ash for corrosion
resistance against sea water. When this breakwater was designed and constructed
100-years ago, 60,000 test pieces of concrete were prepared in order to evaluate the
change in their strength due to aging.
A second example is a straw-bale house made of rice straw compressed into
blocks which are light weight, good insulation of heat and sound, and even fire-
resistant. Straw-bale houses are attracting the attention of people interested in re-
ducing the environmental load and costs in house building. There is a straw-bale
house in Akiu near Sendai city. The wall with 50-cm thick straw-bale coated by clay
mortar attains not only high thermal insulation but also fire resistance. This house is
a Japanese noodle restaurant (Fig.
3.13
).
A third example is the hydraulic ram pump invented in 1796. This pump works
only by the kinetic energy of water flow and there is no need for the electric en-
ergy necessary for an ordinary pump. A long water pipe through which water flows
connects to a chamber having two valves; one is at the exit and the other is at the
entrance of an air chamber. Initially, water is flowing out through the exit valve.
Once the exit valve is closed suddenly, moving water in the long pipe generates a
high pressure in the valve chamber due to the water hammer principle. This high
pressure pushes water into the air chamber and then the exit valve opens again.
Repeating this cycle, compressed water is lifted to higher places and utilized for
various purposes.
A further example is the $ 100 personal computer which was developed in an
educational project for IT popularization. This PC plays a central role for children's
education in developing countries. The PC can be connected to the internet and
charged manually by a rotating handle.
