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Water
Eco-System
The above picturesque images of a clean and happy environment with land, water and life in balance is fast disappearing in many parts of the world. The rate at which we utilize the water is no where near reasonable limits and the clean water supply through precipitation such as rain and snow is become much affected by the drastic climatic changes that have become a reality in the last fifty years in many parts of the world. The lack of foresight on the part of previous generations has left an inheritance of polluted water ways with toxic byproducts of industries and everyday household pollutants being carelessly leaked into the rivers, lakes and oceans. The overall effect of toxicity in water has had a drastic effect on the flora and fauna of both land and water. Some of the contaminants are difficult to remove from the bulk of our environment. The only thing we can hope to do is to reduce the rate of pollution and to conserve the existing resources. Recycling of water has become a necessity in many parts of the world. Recycling technology is non-green and costly in most installations. The tremendous industrialization during the late 1800's and early 1900's saw the focus in mass production and consumer dominated economy. Little or no attention was paid to what was happening to the environment. The water ways and the atmosphere were polluted in an indiscriminate manner. The effect of the damage caused then can now be felt all over the world as gross climatic changes and lack of fresh clean water in many parts of the world. The philosophers and spiritual seekers saw the only solution to this as a total reversal and stopping of further industrialization. Gandhi strongly advocated cottage industries and non-mechanization as the solution to world problems posed by industrial nations. For obvious reasons this failed to work since enforced stoppage of technological advancement is not possible. The change in attitude and a change in consumption driven economy is in fact happening to some extent with greater civic sense and responsibility in society. This has also come about with the revolution in communications technology. There is greater awareness and education of the masses has been achieved even in developing nations. However only a enforced shift to alternate, green and renewable energy resources will effect a immediate impact on the environment. The most noticeable effects of global climatic changes in the last few years has been the lack of seasonal rains in many parts of the world. The very severe draught conditions in many parts of the world had caused the necessity of finding immediate solutions for solving the need to obtain purified water. The technologies that have been developed are the reverse osmosis purification and recycling of waste and sea water. There are other methods of desalination that have been adopted in some countries. One is the solar evaporation condensation. A combination of cooling and generation of distilled water can be achieved using solar energy to power the system. Several countries which have no access to fresh water rely entirely on the efficiency of their water purification, recycling and desalination plants. Some of the east coast states of Australia have had no seasonal rains in the last 15 years. Due to drying up of their natural reservoirs, water recycling and desalination has become top priority. The current technology development for recycling and desalination is still not very cost effective. Some of the desalination plants are not environment friendly and do not always use green renewable energy to operate the plants. The large crude oil reserves of many Middle Eastern countries, along with their relative water scarcity, have led to extensive construction of desalination in this region. Saudi Arabia's desalination plants account for about 24% of total world capacity. The world's largest desalination plant is the Jebel Ali Desalination Plant (Phase 2) in the United Arab Emirates. It is a dual-purpose facility that uses multi-stage flash distillation and is capable of producing 300 million cubic meters of water per year. Comparison of Distillation and Reverse Osmosis Technologies
Advantages of RO plants over distillation include: RO plant feedwater generally does not require heating, so the thermal impacts of discharges are lower; RO plants have fewer problems with corrosion; RO plants usually have lower energy requirements; RO plants tend to have higher recovery rates-about 45% for seawater; the RO process can remove unwanted contaminants, such as trihalomethane-precursors, pesticides, and bacteria; and RO plants take up less surface area than distillation plants for the same amount of water production. If the energy crisis is solved by cheap renewable resource there is hope for cheap recycling of water. There is great deal of development that needs to happen in Desalination and Recycling technologies.
http://www.watermanagementgroup.com/
Grand Canyon re-watered artificially to study effects on the
eco-system
Water, taken in moderation, cannot hurt anybody - Mark Twain
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One
advantage of distillation plants is that there is a greater potential
for economies of scale. Distillation plants also do not shut down a
portion of their operations for cleaning or replacement of equipment as
often as RO plants, although distillation plants can and have shut down
for tube bundle replacement and cleaning. Pretreatment requirements are
greater for RO plants, because coagulants are needed to settle out
particles before water passes through the membranes. Unlike RO plants,
distillation plants do not generate waste from backwash of pretreatment
filters.
