How to Deal with Having Scarcity of Usable Water Resources

Introduction

In countries having scarcity of usable water resources, the requirement of water recycle is very important. Author cited few instances to support this statement. Many countries are making precise arrangement to conserve water, like USA and Israel are using secondary effluent in agricultural activities whereas Japan and some European countries are recycling municipal waste water for toilet flushing and other purposes. Another example cited by author for advancement of water reuse is renowned NEWater, used in Singapore which is a secondary effluent production of domestic wastewater purified by membrane processes. With all the advancement in producing ultrapure water from various waste water sources, the primary concern is their cost per volume of reclaimed water with better treatment choices.

In Taiwan much of the rainfall occurs during sudden typhoons and the country's water infrastructure captures little of it. Island's abundant mountains are washed away by rain. The 1999 earthquake loosened soil that surrounds Taiwan's stressed dams which made water storage problematic. Taiwan being one of the countries known for its semiconductors and agriculture, the water consumption is very high. Therefore, Environmental Protection Administration, Executive Yuan R.O.C. (Taiwan) encourages recycling domestic water and use of it in industries. However the treatment process is not able to remove ammonia and total nitrogen (TN). These contaminants cause corrosion of bronze pipeline and zinc material (Gurrappa 2005). Traditional waste water treatment used by Wastewater Treatment plants is applying activated sludge (AS) process to remove organics and nitrification. TN removal can be achieved by A2O process i.e., Anaerobic/Anoxic/Oxic...

... middle of paper ...

... not considered multiple substrates. Neither have models been extended to circumstances where a fraction of the compounds present at high concentrations may inhibit biodegradation. Only a few studies have used kinetic or mechanistic models to represent substrate degradation, with the majority of the biological studies relying on general parameters. In addition to the experimental and modeling work, the aspect most lacking in this technique used is uncertainty that nitrification may occur less because of the condition created by COD/NH4+-N of 12, which is an important step to achieve denitrification for TN removal.

Domestic Wastewater and Pollution Copyright © 2007 Environmental Protection Administration, Executive Yuan R.O.C. (Taiwan)

• Taiwan faces tough water choices Leon Kaye for Guardian Professional Network

•

• theguardian.com, Friday 24 June 2011 05.00 ED