Page 552 - Industrial Wastewater Treatment, Recycling and Reuse

522 Industrial Wastewater Treatment, Recycling, and Reuse

A big question is: Are we prepared to take on the challenge? From a
technological viewpoint, we respond with a positive and hopeful “yes.”
However, significant efforts are required to change the mindsets of people!
This book has made an attempt to compile some of the available technol-
ogies and to present a coherent picture of the current state of industrial water
treatment, recycling, and reuse. This last chapter represents an epilogue in
which we discuss some aspects of the past, present, and future of this subject.

14.2 THE PAST

Wastewater treatment philosophy dates back thousands of years and was part
of many ancient civilizations, such as those of Rome and the Indus Valley
(Vigneswaran et al., 2011; http://www.lenntech.com/history-water-
treatment.htm). Located near the Indus River in the ancient Indian region,
Mohenjo-Daro represents one of the oldest known systems of wastewater
management, as it is believed to date to around 1500 BC (Wiesmann,
2007). At that time, the local population settled in the vicinity of rivers that
ensured easier supply and discharge of waters. These ancient settlements
were believed to have water supplies and sewerage facilities. The develop-
ment of water transport systems of various forms was crucial and was sup-
plemented by treatment methods. The primary focus in the past was
sewage wastewater treatment, and major treatment processes included seg-
regation, dilution, and filtration in different forms. Though India is facing
severe wastewater treatment problems, and water scarcity today, it is
believed to have history and prior art of water management, disposal of
waste, and health issues that find mention in various forms of literature,
beginning with the Vedas, one the most ancient pieces of literature on Earth.
However, modern world wastewater treatment arrived only a few centuries
back, in about the sixteenth century. The development of physical, chem-
ical, and biological treatments started gradually. The twentieth century saw
the main thrust in this area, and the understanding of wastewater evolved
through the 1900s to the present date.
In the early 1900s, wastewater treatment mainly involved filtration,
settling, and septic tank use. The design of wastewater treatment plants
was also considered, along with the application of disinfection methods,
largely in the form of chlorination. The biological treatment method
also emerged during this period, and the first use of the activated sludge
process(ASP) wasreportedin1916in the USA(http://civil.colorado.
edu/ silverst/cven5534/History%20of%20Wastewater%20Treatment%