Use of waste water from purification plants in the manufacture of concrete

Abstract

The Atacama Region presents cycles of water scarcity
that affect both the population and the productive sectors,
which demand huge amounts of drinking water for its
development. In order to reduce the pressure on the water
resource, it encourages the saving of drinking water
and/or the reuse of sewage and industrial waters. In this
context, the use of waste water from the brackish water
purification processes is a good alternative to drinking
water in the manufacture of mortars and concretes. The
present study evaluates the mechanical behaviour of
the concrete containing waste water generated in the
processes of reverse osmosis and ion exchange. To do
this, four types of water were characterized: drinking
water (control), reverse osmosis waste water process
used in the production of purified drinking water; waste
water of both the ion exchange process and the reverse
osmosis process, both from the Regional Hospital
of Copiapó, Atacama, Chile. Subsequently, different
samples of concrete containing the 4 types of water were
manufactured and their resistance to compression at the
ages of 7 and 28 days was evaluated. The results showed
that in all cases, the concrete made with waste water,
reached higher resistance to compression than the
control sample. From this study, it can be concluded that
the use of waste water in the manufacture of concrete,
can be a convenient alternative for the construction in
arid zones.