Water Ozonation

What is Water?

Water is a ubiquitous chemical substance that is composed of hydrogen and oxygen and is vital for all known forms of life.
Water is courless, odorless & tasteless liquid. However it is one of the most precious & unusual substances found on the earth. It covers more than 70% of the earth's surface. Including the clouds (which are, of course, also water), it makes our entire planet look blue and white from space.
 

Why Water is Important?

It is impossible to overstate the importance of water to almost every process on Earth,70% of earth's surface is water; 75% of human body; and 90% of human blood is water too. Of all the water that's there on earth, 97% is in seas and oceans and 2% is icecaps. Of the remaining 1% fresh water, only a small percentage is accessible. And from what's accessible, 98% water is used for agriculture and industrial use. Maybe now water sounds important to us.
Water's necessity does not end with humans. In fact, water is quintessential part of most living organisms, plant & animal. Water is the most familiar of all chemical compounds known to humans. We drink it, we wash with it, we play in it and we cook in it. In fact, we ourselves are more than half water.
The major sources of water pollution can be classified as municipal, industrial, and agricultural. Municipal water pollution consists of waste water from homes and commercial establishments. For many years, the main goal of treating municipal wastewater was simply to reduce its content of suspended solids, oxygen-demanding materials, dissolved inorganic compounds, and harmful bacteria. In recent years, however, more stress has been placed on improving means of disposal of the solid residues from the municipal treatment processes. The handling and disposal of solid residues can account for 25 to 50 percent of the capital and operational costs of a treatment plant. The characteristics of industrial waste waters can differ considerably both within and among industries. The impact of industrial discharges depends not only on their collective characteristics, such as biochemical oxygen demand and the amount of suspended solids, but also on their content of specific inorganic and organic substances. Three options are available in controlling industrial wastewater. Control can take place at the point of generation in the plant; wastewater can be pretreated for discharge to municipal treatment sources; or wastewater can be treated completely at the plant and either reused or discharged directly into receiving waters.
 

What is water pollution?

Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living thing that drinks or uses or lives (in) it. When humans drink polluted water it often has serious effects on their health. Water pollution can also make water unsuited for the desired use.

 What are the major water pollutants?

There are several classes of water pollutants. The first are disease-causing agents. These are bacteria, viruses, protozoa and parasitic worms that enter sewage systems and untreated waste.
A second category of water pollutants is oxygen-demanding wastes; wastes that can be decomposed by oxygen-requiring bacteria. When large populations of decomposing bacteria are converting these wastes it can deplete oxygen levels in the water. These cause other organism in the water, such as fish to die. A third class of water pollutants is water-soluble inorganic pollutants, such as acids, salts and toxic metals. Large quantities of these compounds will make water unfit to drink and will cause the death of aquatic life. Another class of water pollutants are nutrients; they are water-soluble nitrates and phosphates that cause excessive growth of algae and other water plants, which deplete the water's oxygen supply. This kills fish and, when found in drinking water, can kill young children.
Water can also be polluted by a number of organic compounds such as oil, plastics and pesticides, which are harmful to humans and all plants and animals in the water.
A very dangerous category is suspended sediment, because it causes depletion in the water's light absorption and the particles spread dangerous compounds such as pesticides through the water. Finally, water-soluble radioactive compounds can cause cancer, birth defects and genetic damage and are thus very dangerous water pollutants.
 

 Water Contaminates

• DBP
• Inorganic & Organic Impurities
• Odor & Color Impurities

i. What is DBP?

• Disinfection byproduct (DBPs) is a group of organic & inorganic compounds formed during water disinfection.
• The most common DBPs formed when chlorine is used are trihalomethanes (THMs), and haloacetic acids (HAAs).
• Water systems using sources with higher amounts of organic substances like (Surface waters, such as lakes, rivers and streams) will form more DBPs.

ii. What health effects can DBP cause in human body?

DBPs cause undesirable effects in the human body such as,
• Some people who drink water containing trihalomethanes, haloacetic acid, bromate & chlorite in excess of EPA's standard may experience problems with their liver, kidneys, or central nervous systems, and may have an increased risk of getting cancer.
• Some infants and young children who drink water containing chlorite in excess of EPA's standard could experience nervous system effects. Similar effects may occur in fetuses of pregnant women who drink water containing chlorite in excess of EPA's standard. Some people may experience anemia.

As we understand the water & its water quality, the present system has some drawbacks. We proposed a system can have better performance, efficiency and most importantly is maintaining a good quality of water by implementing following solutions.
 

Advantages of the Ozonation System

• Ozone is effect over a wide pH range and rapidly reacts with bacteria, viruses, and protozoan’s and has stronger germicidal properties then chlorination. Has a very strong oxidizing power with a short reaction time.
• Does not require the on-site storage of other chemicals with the associated hazards and costs.
• Reduces the amount of chlorine required to maintain a residual in the distribution system
• Ozonation can reduce the chemicals needed for flocculation or flotation by 20-50% while improving filter performance due to micro flocculation effect.
• Ozonation provides no germicidal or disinfection residual to inhibit or prevent regrowth.
• Reduces the formation of disinfection by products (DBPs) such as TTHM and HAA5.
• Leaves no toxic residues in the treated water.
• Reduction of COD & BOD Level.
• Dissolved ozone at higher dose does not cause adverse health effects even during long term exposure.
• Ozonation provides no germicidal or disinfection residual to inhibit or prevent regrowth.
• Ozone will oxidize both organic and inorganic substances, remove unwanted taste, odor and color, and provide effective disinfection.
• Ozone inactivates and destroys all bacteria, virus and protozoa’s. Properly dissolved ozone residual a 100% kill of all bacteria, viruses and fungus.