- Copper Refining
- Copper: Foreign location
- Copper Refining: Indian Locations
- Hindalco (Aditya Birla group)
- Sterlite Industry
- Acid Industry
- India Copper Industry: Challenges
- Lead & Zinc Industry
In the previous article, we saw the geographical factors responsible for the location of Aluminium smelting industry. Let’s move to the next topic:
- With 20th century, copper became important for electric industry.
- As the demand for copper increased, new mining-smelting technologies are developed to utilize even lower quality ores.
- Location principle for copper and aluminum industries same, but smelting process is different.
- In case of aluminum, we saw that process is bauxite(ore)=> alumina (weightloss)=> aluminum(need electricity).
- In case of copper, the first stage=concentrating.
Stage: Concentrating ore
- The copper ore is soaked in water and mixed with oils. The copper revering matter floats on the top, and is separated out for further processing.
- After this “concentrating” stage, barely 2.5% of the original matter remains. And less weight= less transportation cost.
- Therefore, copper concentrating mills are set up near the raw material(mines)
- During this stage, sulfur and oxygen impurities are separated from the concentrated copper ore. Thus we get “blister copper”.
- Even in the state, the weight loss ratio is significant, therefore smelting is usually done near raw material.
Stage: blister to copper (refining)
- So far we got copper ore => Blister copper.
- Although Blister copper is 99% pure metal, but still unsuitable for manufacturing electronic wires, utensils etc. Why? Because it contains impurities of gold, silver, lead and zinc.
- Therefore, blister copper is refined via electrolysis method.
- The blister copper is immersed in a bath of copper sulphate, electricity is passed and impurities are removed.
- Here, the weight loss ratio is extremely small. (~1%). So, there is no economic factor to setup copper refining factories near the raw material.
|Zaire and Zambia|
|HINDALCO (Aditya Birla)||@Dahej in Bharuch district of Gujarat.|
|Sterlite Industries.||Tutikorin, TN|
- From the Copper refining process, by products can be used for making phosphoric acid, sulphuric acid. How?
- Copper smelting=>SO2 gas=>Sulphuric Acid
- Same Sulphuric acid + Rock Phosphate*==>Phosphoric Acid. Further it can be used for making fertilizers.
- *by the way, Rock Phosphate is usually imported. (Food for thought: why not setup Phosphoric acid plant abroad then? Ans. Because se SO2 gas is difficult to transport. So, better important rock phosphate here!)
- Hence, such acid industries are located in the vicinity of Copper refineries.
- Nowadays, the copper refining companies have integrated plants to produce such acids within their premises. example
- plant @Dahej in Bharuch district of Gujarat.
- has both Copper refining +Acid production
- From Copper refining, they even extract the impurities of pure gold, silver and selenium, platinum and palladium- which are sold separately.
- Another favorable factor: Dahej port just 45 kms away. Helps exporting sulphuric acid.
- Tuticorin, TN.
- But in 2013, State pollution board ordered them to close down after emission of sulphur dioxide gas = people in the area complained of suffocation, and burning sensation in the eye.
- Matter went to SC, while Sterlite denies emissions from the plant are dangerously high. This plant produces more than half of India’s total refined copper.
- Business GK: Vedanta=London based company. and Sterlite Industries is the subsidiary of Vedanta resources
- Special copper alloys are still imported. Because we don’t have technology to produce them locally. E.g. Beryllium copper,.
- Mining & smelting technology is obsolate. Causes substantial air pollution because sulphur dioxide emission.
- Still don’t have technology for downstream copper products e.g. copper tubes for refrigeration/AC etc. majority of them still imported.
- Still don’t have technology for complete recovery of precious metals such as Cobalt, Nickel etc from copper concentration.
- Producing 1 ton Copper from ore=takes almost 14000 kwh energy. But producing 1 ton copper from scrap/recycling=takes only 1700 kwh. However, scrap based copper smelter are not yet well established in India. Very few plants using scrap metal to recycle copper (e.g.Lonavala, Hyderabad.)
- Manpower requirement per tonne of finished copper=very high compared to developed countries.
- There is huge gap between demand and supply. Almost 70% copper is imported.
- There is no smelter @Malanjkhand (MP). The concentrate has to be transported to Khetri (Rajasthan). =cost of production increases.
- Overall, Indian copper ore is average quality, hence mining/refining is a costly because copper yield is low.
- Dig the ore=>concentrate=> refining.
- it runs on the principle that certain minerals have an affinity for certain oils.
- Hence the ore is mixed with water, oil and chemicals.
- The mineral particles attach with oil bubbles and float on the surface.
- The foam (containing mineral particles) is skimmed off.
- Concentration stage: procedure involves significant weight loss=> carried out near mining site.
- Refining stage: require lot of electricity=> done near large thermal plants /hydroelectric sites.
- India doesn’t have sufficient ores of Lead/Zinc. So majority of our requirement met through imports.
|AP||lead||Vishakhapatnam, based on imported lead concentrates|
|Rajasthan||Zinc||@Debari: ore comes from Rajpur-Dariba mines + import.@Chanderia: ore comes from Bhilwara.|
|Kerala||Zinc||@Always. Based on imported zinc concentrates|
In the next article, we’ll look at the geographical factors responsible for the location of Petroleum Refineries and synthetic textile industry.
visit Mrunal.org/geography for the Archive of all geography articles published so far.