Water, water, everywhere, Nor any drop to drink.

"Day after day, day after day,

We stuck, nor breath nor motion;

As idle as a painted ship

Upon a painted ocean.

Water, water, everywhere,

And all the boards did shrink;

Water, water, everywhere,

Nor any drop to drink."

These are few lines out of 'The Rime of the Ancient Mariner' (The full poem can be read in the next post) by an English poet Samuel Taylor Coleridge. There is water everywhere in the ocean not of any use for it is too salty to be drunk. But the times are changing and it is possible that the water we drink in the future has to come from these oceans itself.

Water, its importance, the impending water crisis and few possible solutions were discussed in the 'International Summit on Water' held recently in Bangalore which I had the privilege to attend and here follows the overview of what I saw there.

Everyone knows that water is one of the most essential resources on this earth and it is very much required to sustain life on this planet. More than 70% of our planet surface is covered by water giving the name ‘Blue Planet’ to Earth. Out of this 70% of the total water, 97% is in the oceans and the remaining 3% is fresh water out of which 1% is available for use and the other 2% is locked in the glaciers and icecaps. The amount of fresh water is limited but whereas the demand for the same is growing in an exponential rate with the increase in the population and industrialization. Satisfying the demand is a major concern and over that, the sources of fresh water are constantly being polluted by the careless actions of man. The rapid rate of industrialization, urbanization and ever increasing population is the main reason for it.

The present day scenario calls for drastic steps to be taken in order to maintain the availability of water to everyone and also to conserve this precious resource. At this rate it is said water will switch places with petroleum to be called as ‘liquid gold’ in the near future and the most probable cause for the next world war will be water. To prevent this situation, we have to divert our attention towards the methods and possibilities of making efficient use of the scientific and natural resources available and come up with come answer and the solutions we have come up with are desalination and waste water treatment. There are many technologies being developed and few of them are already operational.

The International Water Summit 2011 is an initiative which provided the platform for the people working with these technologies can come together, exchange the thoughts, ideas, research work and also to create awareness among the people. This summit was organized by Indian Water Works Association [IWWA] which is a voluntary body of professionals who are concerned and connected with water supply for municipal, industrial, agricultural uses and treatment and disposal of waste water along with MECON which is a premier engineering company, a Government of India PSU who are also responsible for the construction of a 100 MLD desalination plant in Chennai in collaboration with ADECO.

International Summit on Water was a 2 day event held in NIMHANS Convention Centre, Bangalore on the 11^th and 12^th of February 2011. This summit focused on the 2 major areas of Desalination and Waste water treatment. This summit had more than 20 delegates from different institutes and organizations from across the globe presenting their papers.

There were many papers on Desalination technology and the projects being underway in various parts of the world, including the methods being utilized in the construction of the sea water Reverse Osmosis System to obtain desalinated water and also different purification and pretreatment methods studied in order to cater the demand during the upcoming Olympics in London. There were also representatives from the companies like Hyflux who manufacture equipments for SWRO plants discussing about the various pretreatment methods being used which is generally ultra filtration and the various types of filter cartridges available along with their lifespan. Mr. Dong Fei Li also compared the different types of desalination technologies used namely SWRO, MSF (Multistage Flash Distillation) and MED (Multiple Effect Distillation) and reasoning why SWRO is better than the other 2 process in terms of energy consumption and material costs. The plants having largest desalination capacity are situated in Asia at present and one such plant is SingSpring plant situated in Singapore which was presented as a case study.

The Desalination processes consumes a lot of energy and minimizing the energy consumption as much as possible makes the process more economical and in order to minimize the energy consumption, energy recovery devices like pressure exchangers (PX) are used. These PXs are installed in the flow system and it utilizes the energy from the high pressure reject steam to pressurize the cool inlet stream. The principle of working of these Energy Recovery Devices (ERD) and the various models available were made known by Mr.Madurakavi Kumar from Energy Recovery Inc.

There were papers which dealt with the recent trends and the development of the desalination technology in India and with specific reference to a MED plant in Gujarat and also the projects being undertaken by WABAG INDIA in Chennai. Indira Gandhi Centre for Atomic Research, Kallapakam is a Nuclear Installation under the Department of Atomic Energy, GOI and they have also set up a hybrid SWRO/MSD desalination plant to meet their year round requirement of fresh water and also make use of the high temperature steam generated by the power plant.

There are various programs which are designed for automation and monitoring of the SWRO plants which make the maintenance of these plants easier thereby making it possible to keep it operational round the year except for periodic maintenance when required. And the maintenance and automation solutions are supplied by ABB through their OPTIMAX Membrane Performance solutions.

It is a well known phenomenon that as the pressure decreases, the boiling point of the liquids will also decrease and by making use of this phenomenon the people at National Institute of Ocean Technology, Chennai have come up with an efficient plan of desalinating sea water. Now coming to industries, boilers are an integral part of many industries and these boilers need feed water , and for continuous operation they need hundreds of gallons of water free from salts as the salts may lead to scaling in the boilers and procuring fresh water from natural sources is not always a viable option so in order to overcome this, BHEL, Ranipet has set up a RO-DM plant to treat the agricultural runoff water and utilize it as feed water for boilers thus cleaning up the Agricultural run-off water which will be having high levels of colloids, minerals, pathogens along with fertilizers and pesticides and also making efficient use of the water resources. Here they pump and store the agriculture run-off water in a pond and later is subjected to a series of operations which include clarifying and filtering through a series of Pressure Sand Filters (PSF) and Activated Carbon Filters (ACF) and later subjecting it to RO process and further treatments.

The Desalination plants do have few effects on the ecosystem and nature due to the production of heat as well as concentrated brine which is again let out to the sea which causes variations in the density, temperature and salinity of the sea water in those areas of discharge which needs to be evaluated and corrective measures taken.

As the population increases the amount of sewage produced also increases and it is necessary to treat the sewage and make use of the treated water for indirect potable use and Pall has come up with Aria series of microfiltration modules which has been approved by the California Health Dept and is being used for municipal water recycling. Right now this process is in place in the state of California, USA and the water produced is used of irrigation, as boiler feed and also supplied to University of California, Davis for various needs. MF procedure is also used for secondary treatment of waste water before letting it out into the rivers. This is found to be a very cost effective procedure.

Steel industry is one of the biggest consumers of industrial water and as the supply of fresh water is drying up, the steel industry is now facing the dual challenge of increasing production and reducing consumption of water. This is only possible when wastewater is recycled after treatment and near-zero discharge level is achieved and consumption of water per unit of steel production is minimized. These challenges can be effectively addressed by properly using existing knowledge of water and wastewater treatment and simultaneously adopting emerging technologies.

Along with these there were also discussions and presentations regarding the studies and steps taken by BWSSB for monitoring and removal of Endocrine Disrupting Chemicals (EDC) present in water by adsorption, advanced chemical oxidation and other membrane processes. The initiative taken by the Jayadeva Institute of Cardiology to use treated water wherever possible by setting up a treatment plant in their backyard was also one of the interesting topic.

The new thing under development in the process industries is known as ZLD or Zero Liquid Discharge processes, which are being developed and studied by various industries in India and around the world. Apart from all these, there were also discussions regarding the recent emerging trends in the field of municipal waste water treatment, reducing the production of waste water by making use of water efficient systems in day to day life and also usage of modern nanofiltration techniques for water purification and various methods for recovery of certain metals and also petroleum residues from the waste water.

This summit addressed almost all the major water issues being faced at present and near future and also the steps that has to be taken in order to prevent the water crisis. Apart from desalination and waste water treatment, using water judiciously and conserving it will solve half of the problems regarding water shortage.

Now, I did learn something or rather many things out of this summit. Should make it a point to attend more of these kind of things.