JNARDDC Technology for Spent Pot Lining Utilisation New Delhi 22 nd September, 2015
Earth Crust Metal of Future Abundant element- 3 rd Most abundant metal - 8% Aluminium Age Total metals available- 32% Growth Strategic Metal Largest growing metal (9.45X) since 1960 followed by Cu, steel (4.56X), Pb, Sn etc. Green Metal Volume Metal used - 2 nd largest Non ferrous industry – 1 st Al Indust Al Industry y is is the onl the only y indust industry y in t in the he Wor orld t ld to o claim laim to to become g become green house een house gas (GHG) neutr gas (GHG) neutral, al, by t by the y he year ear 2030 2030
New capacities : Asia to dominate
Bauxite Reserves
Coal Reserves • India • Reserves 250 bn tons • Production 605 million tons Source:www.coalindia.nic.in Bauxite and Coal are found in roughly the same geographies
Manpower Reserves • India has a formidable pool of manpower – both skilled and unskilled • India and China have cheaper manpower as compared to developed countries Comparison of Labour Rates ( USD/hr) 23 20.5 2004 2009 2014 18.9 18.7 17.5 15.9 15.9 15.7 14.8 14.4 11.6 11.2 10.2 10.1 9.1 9 8.5 7.1 1.3 1.3 1.2 1.1 0.9 0.9 0.7 0.7 0.9 India China S E Asia Taiwan Korea ANZ Japan Germany USA
Demand
Advantage India…
Waste Generation in Al Industry Bauxite 5-6t Waste 8-10t 3-4t RM Aluminium 1 t 15-20kg Dross 30-40kg SPL 2.0 – 3.0 ton CO 2 -D CO 2 -ID 14-15 ton
Section View of H-H Pot
Section View of Cathode SPL-- Cathode lining- 1 st cut (Carbon Portion) SPL--Refractory lining- 2 nd cut (Refractory portion)
Spent Pot Lining • Life of pot is 2500-3000 days • SPL generation is 3-5% of Aluminium Production • 0.6-0.8 lakhs tons of SPL generation annually in India
Cement – SPL Issues • Hard material, crushing of SPL is a problem • Bond index of lime stone is 13-15 and of SPL is around 40-45 (lime crusher not feasible) • Plants are not coming forward because of its transportation cost and initial capital investment • Continue availability of raw material is also an issue • GCV value of SPL is around 6000 & hazardous substance in SPL is CN and Fluoride
Typical Composition of SPL – 1 st Cut Major components First Cut (%) SPL SiO 2 1-8 SPL is listed as a hazardous Al 2 O 3 8 - 20 waste (K088) by Environmental Protection Agency (EPA) Na 2 O 10 - 15 CaO 1-3 TOTAL CYANIDE : > 590 ppm LEACHABLE CYANIDE : > 30 C 54-66 ppm F 6 - 12 Total Cyanide 100 - 1000 ppm Leachable Cyanide 100 - 600 ppm An increasing number of countries are banning the traditional method of landfill disposal of SPL due to presence of significant quantities of fluorides and cyanides.
Work Carried out at JNARDDC
Crushing to -2+1mm Heat Treatment Process SPL from Plant
Destruction of Leachable Cyanide >97% 120 % Leachable cyanide destruction 100 80 60 40 20 0 0 100 200 300 400 500 Temperature (°C)
Gas Liberation during Heat Treatment of SPL Tests Carried Out 1. NaOH solution- 2. Distilled water with 2-3 Heat treatment temperature colorless drops of phenolphthalein indicator — colourless • Solution • Colour change to pink ~ 425 °C titrate with AgNO 3 , no Cyanide (liberation of NH 3 gas) found • Solution analysed on ion analyser, no Fluoride found
SPL Treatment with Recovery of Soda & Fluoride - Flow Sheet -
Bench Scale Unit
Carbon Residue free of Soda & Fluorides
JNARDDC along with NALCO has commercialised SPL treatment technology
JNARDDC SPL Technology • SPL into an environmentally stable product • Technology tolerant of a fluorine environment • Safe treatment of problematic orphan SPL • Compact plant that can be readily installed • Recover fluorine and energy for the aluminium production process
JNARDDC Major R&D Projects
Waste Utilisation • Pilot plant setup – “ Swachh Bharat Abhiyaan ” – “Vision 2022” – BMTPC/NALCO/Ministry of Mines – SPL utilisation & fluroides recovery- NALCO / Green Energy resources / Vedanta – Dross to Alum & Refractory - Vedanta
Downstream • Super Thermal Aluminium Alloy – MoM/NFTDC • Extrusion facilities like die design, die fabrication, prototype product etc. For MSME – MoM / Local Extrusion Industry • Setting up of pilot plant facilities for casting, rolling & forging – MoM / MSME
Bauxite / Alumina / Aluminium • Upgradation of low grade E/W coast bauxite - MoM • Proppant from PLK & flyash - NALCO • Refractory from saprolite – MoM • Low soda Hydrate – MoM • Liquidus and alumina % measurement instrument – MoM / Vedanta
Thank You Anupam Agnihotri Director Jawaharlal Nehru Aluminium Research Development & Design Centre, Nagpur director@jnarddc.gov.in +91 7104220763 +91 9404084435 www.jnarddc.gov.in
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