RENEWABLE & NON RENEWABLE RES OURCES

Transcription

1 Lecture 10 NATURAL RESOURCES: RENEWABLE & NON RENEWABLE RESOURCES Mineral Resources By Prof. S. P. Bajpai

2 2 MINERAL RESOURCES: Minerals are naturally occurring, inorganic, crystalline solids having a definite chemical composition and characteristic physical properties. Minerals can be classified as macro minerals and minor minerals depending of their role in living system whereas can be divided as critical minerals (essential for economy of the nation like gold, aluminium, copper) strategic minerals (required for the defence of the country like Mn, platinum, cobalt, chromium) There are thousands of minerals occurring in different parts of the world. However, most of the rocks, we see everyday are just composed of a few common minerals like quartz, feldspar, biotite, dolomite, calcite, laterite etc. There minerals, in turn, are composed of some elements like silicon, oxygen, iron, magnesium, calcium, aluminium etc.

3 3 Use and Exploitation: Minerals find use in a large number of ways in everyday use in domestic, agricultural, industrial and commercial sectors and thus form a very important part of any nation's economy. The main uses of minerals are as follows: Development of industrial plants and machinery. Generation of energy e.g., coal, lignite, uranium. Construction, housing, settlements. Defense equipments - weapons, armaments. Transportation means. Communication - telephone wires, cables, electronic devices.

4 4 Medicinal system - particularly in Ayurvedic system. Formation of alloy for various purposes (e.g., steel alloys) Agriculture - as fertilizers, seed dressings and fungicides (e.g., zineb containing zinc, maneb - containing manganese etc.) Jewellery - e.g., gold, silver, platinum, diamond.

5 Major Reserve and important uses of some of the major metals Metal Major World reserve Major Uses Aluminium Australia, Guinea, Jamaica Packaging food item, transportation, utensils, electronics Chromium CIS, South Africa For making high steel alloy, in textile and tanning industries Copper Iron USA, Canada, CIS, Chile, Zambia CIS, South America, Canada, USA Electric and electronic goods, building, construction, vessels Heavy machinery, steel production, transportation means Lead CIS, USA Car batteries, paint industries, ammunition

6 Metal Major World reserve Major Uses Platinum Group Gold Silver Nickel South Africa and CIS CIS, South Africa and Canada Canada, South Africa, Mexico CIS, Canada, New Caledonia Manganese South Africa, CIS, Brazil, Gabon Use in automobiles, catalytic converters, electronics, medical uses Ornaments, medical use, electronic use, use in aerospace Photography, electronics, jewellery Making Alloys, Electronics, Automobiles For making high strength, heat resistant steel alloy

7 7 Major Minerals of India: Bauxite Ore (Aluminium): The total in situ reserves is million tonnes. About 84 per cent of this reserve is of metallurgical grade. The conditional resources of bauxite are about 5, 99,780 tonnes. In addition, prospective resources are placed at 90 million tonnes. Orissa, Andhra Pradesh, Chhattisgarh, Gujarat, Maharashtra and Jharkhand are the principal states where bauxite deposits are located. Major reserves are concentrated in the East Coast Bauxite deposits of Orissa and Andhra Pradesh.

8 8 Chromite: Total in situ reserves of chromite are estimated at 114 million tonnes. Total geological resources were estimated at 187 million tonnes, consisting of around 114 million tonnes in situ reserves and about 73 million tonnes as conditional resources. The largest share (about 96 per cent) in the total geological resources is accounted by the Cuttack district in Orissa. Deposits of economic significance occur in Orissa, Karnataka, Maharashtra, Jharkhand, Madhya Pradesh, Chhattisgarh, Tamil Nadu and Manipur. However, refractory grade reserves of chromite are very meagre.

9 9 Copper: The total in situ reserves of copper ore in the country are million tonnes, equivalent to 9.4 million tonnes of metal content. The all-india conditional resources of copper are 722 million tonnes (3.15 million tonnes of copper metal) and prospective resources are 0.6 million tonnes of copper ore. Major and important copper ore deposits are located in Singhbhum district (Jharkhand), Balaghat district (Madhya Pradesh) and Jhunjhunu and Alwar districts (Rajasthan). In addition, there are small copper ore deposits in Gujarat, Karnataka, Andhra Pradesh, Uttar Pradesh, Sikkim, Meghalaya, Maharashtra and West Bengal. Chalcocite Cuprite

10 1 Gold: There are three important gold fields in the country, namely, Kolar Gold Fields, Kolar district, Hutti Gold Field in Raichur district (both in Karnataka) and Ramgiri Gold Field in Anantpur district (Andhra Pradesh). Total in situ reserves of gold ore are estimated at 22.4 million tonnes, with tonnes of metal.

11 1 Iron Ore: The total in situ reserves of iron ore in the country are about 1,23,17,275 thousand tonnes of haematite and 53,95,214 thousand tonnes of magnetite. The resources of very high-grade ore are limited and are restricted mainly in the Bailadila sector of Chhattisgarh and to a lesser extent in Bellary-Hospet area of Karnataka and Barajamda sector in Jharkhand and Orissa. Haematite resources are located in Orissa, Jharkhand, Chhattisgarh, Karnataka, Goa, Maharashtra, Andhra Pradesh and Rajasthan. Magnetite resources are located in Karnataka, Andhra Pradesh, Goa, Kerala, Jharkhand, Rajasthan and Tamil Nadu.

12 1 Lead-Zinc: Lead-Zinc resources are located in Rajasthan, West Bengal, Andhra Pradesh, Gujarat, Madhya Pradesh, Uttar Pradesh, Orissa, Maharashtra, Meghalaya, Tamil Nadu and Sikkim. Total in situ reserves (all grades) of lead and zinc ores are 231 million tons comprising metal content of 5.1 million tons of lead and million tons of zinc metal. Galena (PbS

13 1 Manganese: The total in situ resources of manganese ore are 406 million tonnes out of which 104 million tonnes are proved, 135 million tonnes are in probable and 167 million tonnes are in possible categories. Main reserves fall in Karnataka, followed by Orissa, Madhya Pradesh, Maharashtra and Goa. Minor occurrences of manganese are in Andhra Pradesh, Jharkhand, Gujarat, Rajasthan and West Bengal.

14 1 Tungsten: The total in situ reserves of tungsten ore have been estimated at million tonnes or 1, 32,478 tonnes of Wo 3 content. The main reserves are at Degana, Rajasthan. It also occurs in Maharashtra, Haryana, West Bengal and Andhra Pradesh. Dolomite: Dolomite occurrences are widespread in almost all parts of the country. The total in situ reserves of all grades of dolomite are 7,349 million tonnes. The major share of about 90 per cent reserves is distributed in the states of Madhya Pradesh, Chhattisgarh, Orissa, Gujarat, Karnataka, West Bengal, Uttar Pradesh and Maharashtra wolframite

15 1 Diamond: Diamond deposits occur in three types of geological settings such as Kimberlite pipes, Conglomerate beds and Alluvial gravels. The main diamond bearing areas in India are the Panna belt in Madhya Pradesh, Munimadugu- Banganapalle conglomerate in Kurnool district, Wajrakarur Kimberlite pipe in Anantapur district and the gravels of Krishna river basin in Andhra Pradesh. Reserves have been estimated only in the Panna belt and Krishna Gravels in Andhra Pradesh. The total in situ reserves are about 26,43,824 carats.

16 1 Fluorspar: Total in situ reserves of fluorspar in India are million tonnes. Commercial deposits of Fluorspar are located in Gujarat, Rajasthan, Madhya Pradesh and Maharashtra. Gypsum: The in situ reserves of gypsum are estimated at 383 million tonnes. Out of this, two millions are of surgical/plaster grade. 92 million tonnes of fertilizer/pottery grade, 76 million tonnes of cement/ paint grade, 13 million tonnes of soil reclamation grade and the rest is unclassified. The production of gypsum is confined to Rajasthan, Tamil Nadu, Jammu and Kashmir, and Gujarat. Rajasthan is the main producer of gypsum followed by Jammu and Kashmir.

17 1 Graphite: The in situ reserves of graphite are 16 million tonnes. Orissa is the major producer of graphite. Almost the entire reserves of Tamil Nadu under the proved category are in Ramanathapuram district. Deposits of commercial importance are located in Andhra Pradesh" Jharkhand, Gujarat, Karnataka, Kerala, Madhya Pradesh, Maharashtra, Orissa, Rajasthan and Tamil Nadu.

18 1 Limestone: The total in situ reserves of limestone of all categories and grades are placed at 1, 69,941 million tonnes. The total conditional reserves have been estimated at 3,713 million tonnes. The major share of its production comes from Madhya Pradesh, Chhattisgarh, Andhra Pradesh, and Gujarat: Rajasthan, Karnataka, Tamil Nadu, Maharashtra, Himachal Pradesh, Orissa, Bihar, Uttaranchal and Uttar Pradesh. The remaining part comes from Assam, Haryana, Jammu and Kashmir, Ker and Meghalaya.

19 1 Mica: India is the world's leading producer of sheet mica and accounts for about 60 per cent of global mica trade. Important mica-bearing pegmatite occurs in Andhra Pradesh, Jharkhand Bihar and Rajasthan. The in situ reserves of mica in Andhra Pradesh are 42,626 thousand tonnes, Bihar 12,938 tonnes, Jharkhand 1,494 tonnes and in Rajasthan 2,007 tonnes. Magnesite: The total in situ reserves of Magnesite are about 415 million tonnes of which 76 million tonnes are in the proved category. Major deposits of magnesite are found in Uttaranchal, Tamil Nadu and Rajasthan while minor deposits are in Jammu and Kashmir, Karnataka, Himachal Pradesh and Kerala.

20 Coal and lignite: West bangal, Jharkhand, Orissa, Madhya Pradesh, Chattisgarh, Andhra Pradesh Uranium (Pitchblende or Uranite ore): Jharkhand, Andhra Pradesh, Meghalaya, Rajasthan

21 2 Other Minerals: Other minerals occurring in significant quantities in India are bentonite (Rajasthan, Gujarat, Jharkhand and Jammu and Kashmir), corundum (Karnataka, Andhra Pradesh, Rajasthan and Chhattisgarh), clacite (Andhra Pradesh, Rajasthan, Madhya Pradesh, Tamil Nadu, Haryana, Karnataka, Uttar Pradesh and Gujarat), fuller's earth (Rajasthan, Jharkhand, Bihar, Andhra Pradesh, Tamil Nadu, Maharashtra, West Bengal and Karnataka), granite (TamilNadu, Orissa, Andhra Pradesh, Rajasthan and Kerala), pyrites (Jharkhand; Rajasthan, Karnataka, Himachal Pradesh and Andhra Pradesh), steatite (Rajasthan, Uttar Pradesh, Kerala, Maharashtra and Madhya Pradesh).

22 2 Wollastonite (Rajasthan and Gujarat), zircon (beach sand of Kerala, Tamil Nadu, Andhra Pradesh and Orissa) and quartz and silica minerals are widespread and occur in nearly all states. Besides, the country has vast marble, slate and sandstone. Granite is mainly mined in Tamil Nadu, Karnataka, Andhra Pradesh and Rajasthan; marble in Rajasthan, Gujarat and Uttar Pradesh; slate in Chhattisgarh, Madhya Pradesh. Haryana and Andhra Pradesh; and sandstone in Rajasthan.

23 2 Mining: Mining is the process of taking mineral and other substances from the earth. These substances include metal compounds, non-minerals such as coal, sand, oil and natural gas and many other useful things. Mining provides iron and copper for making aero planes, refrigerators etc. Mines also supply salt for food, gold, silver and diamonds for jewellery; and coal for fuel. We mine uranium for nuclear energy, stone for buildings, phosphate for fertilizers and gravel for roads.

24 2 Types of Mining: Open-cast or surface mining In this type of mining the minerals or rocks that are to be mined are exposed at the surface or very close to the surface.

25 2 Strip mining process: As the name suggests the surface of the earth is stripped. In this process the soil and rocks that lie above is removed generally by heavy machinery and then the material is extracted. This type is possible only when the targeted materials are relatively near the surface. The mineral generally extracted is coal or some kinds of sedimentary rocks.

26 2 Placer mining process: In this process alluvial deposits in sand or gravel are extracted. This process does not involve the usage of any sort of heavy materials and can be considered relatively easy when compared to others. Generally gold and other gemstones are mined in this process.

27 2 Mountain top process: This process involves blasting of the top of mountains expose the coal below it. This process is relatively new.

28 2 Hydraulic mining process: In this process high pressure water jets are used to dislodge rocks and minerals. During earlier times gold was found in an easier way by this method. However, this process has been discontinued due to environmental concerns.

29 2 Dredging process: It is the process of underwater excavation by deepening a water body. In this method sediments and other substances are removed from harbors, rivers and other water bodies and minerals are extracted.

30 3 Open pit process: The easiest and the cheapest way to mine materials that are close to the surface, large open holes are dug in the ground. Sometimes, explosives are used to get large blocks of rocks out of the way. (Bingham Canyon 1.2 km deep and 4 km wide)

31 3 1. Slope mining process: A type of underground mining, slopes are made into the ground and the desired material is accessed. This is done when the minerals are located far enough and surface mining cannot be employed to reach it. Generally, coal is mined in this way.

32 3 2. Hard rock process: Here tunnels deep in the ground are dug sometimes with dynamite or large drills. The tunnels are supported by pillars through which miners can move about. Tin, lead, copper, silver, gold etc. are mined with this process. This is typically the mine that comes to our minds when we think of it.

33 3 3. Drift mining process: This process is carried out when the material is situated sideways of a mountain. The materials are easier to access and the mouth is made slightly lower than the resource area so as to allow gravity to pull down the materials easily. Generally, coal or iron ore is mined through this process.

34 3 4. Shaft process: The deepest form of underground mining, this is done by excavating a vertical passageway deep down. The materials to be extracted are situated deep inside and elevators are used to take the miners up and down. It is kept in mind that the tunnels are made airy for miners to work without any problems. Generally, coal is mined in this process.

35 3 5. Borehole process: Using a drill a deep hole is dug and a high pressure water-jet is used to force the materials up the hole. Sand, galena, gold etc. are mined by this process.

36 3 Impacts of Mining: De-vegetation and defacing of lands: Mining requires removal of vegetation along with underlying soil mantle and overlying rock masses. This results in destruction of landscape in the area. Subsidence of land: Subsidence of mining areas results in tilting of buildings, cracks in houses, buckling of roads, bending of rail tracks and leaking of gas from cracked pipe lines leading to serious disasters. Groundwater contamination: Mining pollutes the groundwater. Sulphur, usually present as an impurity in many ores is known to get converted into sulphuric acid through microbial action, thereby making the water acidic.

37 3 Surface water pollution: Sulfur in one react with water and oxygen to form sulfuric acid which leaks out from the mine. This is known as acid mine drainage. The acid mine drainage often contaminates the nearby streams and lakes. It severally degrades water quality, and can kill aquatic life and make water virtually unusable. The radioactive substances like uranium, heavy metals also contaminate the water bodies and kill aquatic animals. Noise Pollution: The ground and noise vibrations are produced during miniming operations such as drilling and blasting, movement of mining equipments like shovels, dumpers, drills, dozers, rippers etc.

38 3 Air pollution: In order to separate and purify the metal from other impurities in the ore, smelting is done which emits enormous quantities of air pollutants. Oxides of sulphur, arsenic, cadmium and lead etc. shoot up in the atmosphere near the smelters and the public suffers from several health problems. Occupational Health Hazards: Miners working in different type of mines suffer from asbestosis, silicosis, black lung disease.

39 3 Remedial Measures: In order to minimize the adverse impacts of mining, it is desirable to adopt eco-friendly mining technology like: Using microbial leaching technique. Acidithiobacillus ferrooxidans and Acidithiobacillus (form early known as Thiobacillus), Aspergillus niger, Penicillium simplicissimum can be used for the leaching of ores of Fe and Gold. Restoration of mined areas by re-vegetating them. Stabilization of the mined lands. Prevention of toxic drainage discharge. Gradual restoration of flora.

40 Case Studies 1. Improper waste disposal in Malanjkhand s Copper mines: Acidic threat: In Balaghat s Birsa Block M.P. 2. Mining and quarrying in Udaipur 3. Mining in Sariska Tiger Reserve in Aravallis 4. Uranium mining in Nalgonda, A.P.