Water Pollutants and uses
Water • H20 • 75% of • 98% is • Less than 1% of • Glaciers hold most of the
Water • Used to help create • Tundra • Taiga (Pines)
Water • Deciduous Forest • Tropical Rainforest
Water • Grassland • Desert
Water pollutants • In 1974, Congress passed the • This law requires EPA to determine safe levels of chemicals in drinking water which do or .
Nitrates • (NO3)-1 • The MCLG for nitrates has been set at 10 parts per million (ppm), and for nitrites at 1 ppm • EPA believes this level of protection would not cause any of the
Nitrate • What are the health effects? • Short-term: Excessive levels have caused . • The serious illness in infants • Conversion of nitrate to nitrite by the body, which can interfere with the • Symptoms include shortness of breath and .
Nitrates • Long-term: Nitrates and nitrites have the potential to cause the following effects from a lifetime exposure at levels above the MCL: • Diuresis • Starchy deposits • Hemorrhage of spleen
Phosphate • (PO4)-3 • This element is required for the • Used in the manufacture of proteins in • Phosphorus is essential for
pH • The indicator for acid, or base is known as the pH value. • A pH value of 7 means a • The lower value (1-6) indicates . • A higher value (8-14) is a sign of a .
pH • Apple Juice - 3 • Orange Juice - 3.5 • Coffee - 5.5 • Milk - 6.2 • Baking Soda - 8.5 • Soapy water - 10 • Bleach - 12
pH • Ideal pH level of drinking water should be between, • The human body maintains pH equilibrium on a constant basis and will not be affected by . • Our stomachs have a naturally low pH level of 2 which is a beneficial acidity that helps us with .
Dissolved Oxygen • A high DO level in a community water supply is good because it makes • High DO levels speed up • Industries use water with the least possible amount of .
Dissolved oxygen • The amount of dissolved oxygen often determines the number and types of organisms . • Fish like trout are sensitive to low DO levels (less than eight ppm) and cannot survive in warm,
Dissolved Oxygen • Decay of organic material in water caused by either chemical processes or microbial action on untreated sewage will • Dead vegetation can severely • This is the most common cause of fish kills, especially in summer months when .
Silica • The silica content of water ranges from a few ppm in surface supplies to well over 100 ppm in certain well waters. • In water treatment, we are concerned with silica because of its capacity to form . • In its colloidal (suspended) form it consists of very .
Silica • Silica Removal Processes: • Filtration • Chemical precipitation • Reverse Osmosis • Strong base and ion exchange
Reverse Osmosis • The solute is retained on the • The pure solvent is allowed to • This membrane should not allow large molecules or , • Smaller components of the solution
silica • When complete silica removal is required, various combinations . • RO systems are currently unable to • RO is far better at removing various forms of non-reactive silica and will remove many additional contaminants
CO2 • Rainwater is slightly acid and will absorb additional amounts of carbon dioxide if it . • During process • If the water now passes through limestone formations, its carbonic acid content will react with the limestone to form soluble calcium bicarbonate. .
CO2 • If the water now passes through limestone formations, its carbonic acid content will react with the limestone to form . • In this process the
CO2 • If nature or chemical agents do not neutralize carbonic acid, it will cause . • In those parts of the country where the problem is prevalent it can lead to
CO2 • Carbon dioxide, with carbonic acid, is primarily a problem in water containing relatively . • In such water there are not sufficient . • Alkaline salts or basic salts are salts which are the product of the neutralization of a .
Hardness • Hard water is water with a high mineral content, • It is not necessarily harmful to our health • Hard water poses a threat on appliances because it forms a scale which is an
Hardness • When this scale builds up • Decrease in water pressure and • In Northeast MN,
hardness • Hard water • When these ions react with • This means more soap will be used in the process of . • It also means the