Waterpollution1

Water Pollution MAJID MOHIUDDIN

CLASSIFICATION OF WATER POLLUTANTS 8. Fallout products, radioactive waste etc. 8. Radioactive substances 7. Silt from land erosion 7. Suspended materials 6. Water used for cooling in industry. 6. Heat 5. Hg, Cd 2+, Pb 2+ , etc. 5. Inorganic chemicals 4. Nitrates, phosphates. 4. Plant nutrients 3. Detergents, oil, insecticides. 3. Organic molecules 2. Bacteria and viruses 2. Infectious agents 1. Human, animal waste, decaying vegetation. 1. Oxygen demanding wastes Examples Type

INORGANIC POLLUTIONS AND TOXIC METALS

Acids and Alkalies – Industries manufacturing hydrochloric, nitric, sulphuric and phosphoric acids, sulphur dioxide, chlorine, oxides of nitrogen, ammonia and bases of sodium, potassium and calcium etc.

- Effluents from paper, tanning and textile industries.

2. Soluble Salts – A variety of salts containing anions of carbonate, bicarbonate, acetate, nitrate, nitrite, fluoride, chloride, bromide, iodide, sulphate and phosphate as well as sulphides of copper, cadmium, mercury, zinc, nickel, manganese, cobalt, lead, tin, iron and arsenic etc.,

3. Insoluble Salts – Insoluble salts of calcium sulphate, calcium carbonate, dust and particulates etc., are insoluble in water but they create enormous water pollution.

4. Polyphosphates – in detergents - algal nutrients .

5. Acid Mine Drainage – acid rain pollution – Sulphuric acid and ferric hydroxide.

6. Inorganic Pesticides – copper, cadmium, iron, manganese, zinc and cobalt are the chronic water pollutants.

ORGANIC POLLUTANTS

Water system through domestic sewage.

Industrial wastes from paper mills and tanneries.

Waste from slaughter house.

Meat packing plants.

Food processing plants.

Plant nutrients.

Detergents.

Biocides.

Run off from crop lands.

Decomposition products of organic compounds.

Organic pollutions in water may be categorized as follows:

Carbohydrates and Proteins

- Household wastes in sewage and faecal matter

- Sugar

- Sweet

- Glucose industries

- breweries

- Dairies,

- Food processing

- Starch

- Cellulose

- Sucrose

- Glycogen

- Dextrin

- Alginic acid

- Amino acids,

- Albumin

- Gelatin

- Casein

- Keratin etc.,

2. Oils – aesthetic problems.

3. Aldehydes – Acetaldehyde, benzaldehyde, furfural, formaldehyde and vanillin etc., - inhibit algal growth

4. Polychlorinated Biphenyls (PCBs) – used in dielectrics, lubricants and plasticizers – physiological effect and central nervous system and respiratory tract.