Sustainable Processing of Deep-Sea Polymetallic Nodules

  • P. K. SenEmail author


The possibility of commercialization of processing technology for sea nodules has been linked with comparisons with similar terrestrial process operations. In addition to techno-economic viability, an added focus to commercialization is the sustainability of the process route. The general context of sustainability is discussed. The importance of material flow analysis, recycle rates of the metals produced as well as the possibility of a flow sheet being developed to supply short supply critical metals are brought out in this context. Environmental management for flow sheets under development is important for sustainable operations. Cradle-to-gate environmental burdens such as greenhouse gas emissions and solid waste burden both for common metals as well as for several other metals are provided as a basis of comparison. Polymetallic nodules (PMN) have been likened to low-grade manganese ores where three approaches have been reported for processing. Two of these approaches involve initial processing similar to laterite ore processing for recovery of Ni, Cu, and Co followed by manganese recovery similar to terrestrial ferroalloy production/manganese compound precipitation. The third approach attempts manganese recovery as ferroalloy followed by recovery of Cu, Ni, and Co as practiced for terrestrial sulfide ores. The relatively high values of gross energy requirements and emissions for terrestrial Ni and Co as compared to common metals point out that flow sheet development effort needs to focus on controlling these parameters for a nodules processing operation. On the other hand, these parameters have relatively low values for manganese ferroalloys produced from terrestrial resources. Production of ferroalloys from sea nodules needs to be comparable to their production from land resources. An approach for impact analysis is evolved where a system expansion strategy is followed for Cu, Ni, and Co with a subprocess of recovering manganese bearing ferroalloy. Regarding the later process step, both the Gross Energy Requirement (GER) and Emission (150 MJ and 10 t CO2/t ferroalloy produced) far exceed the terrestrial processing values. For recovery of Ni, Cu, and Co, the results are process specific. For a roast reduction ammoniacal leach process, an energy input of 525 MJ and 40 kg CO2/kg of Ni equivalent is estimated as compared to 200 MJ and 12 kg CO2/kg of nickel equivalent for a complete hydrometallurgical process. Thus, the roast reduction ammoniacal leaching process is not sustainable for sea nodules processing for recovery of Ni, Cu, and Co because of high GER values and high specific CO2 emissions. The high pressure acid leaching route has comparable values to similar laterite processing operations. For flow sheet concepts involving manganese dissolution, recovery of manganese as electrolytic manganese dioxide is less energy intensive compared to residue smelting operation with high gross energy requirements and emissions. For nodule processing flow sheets involving use of energy chemicals (NH3, HCl, H2),appropriate reagent recycle schemes for reagents need to be conceived; else process integration with external flow sheets needs to be contemplated for enhancing sustainability. Considering resource crunch of rare earth elements with respect to terrestrial resources, the recovery of rare earth from sea nodules will enhance the sustainability of the sea bed deposits.



Parts of this write-up are based on an invited lecture by the author on “Metals, Materials and Sustainability” delivered in 2015.


  1. Andrews BV, Flipse JE, Brown FC (1983) The economic viability of a four metal pioneer deep ocean mining venture. Texas A&M University, College Station, TX, pp 84–201Google Scholar
  2. Azapagic A, Perdan S (2000) Indicators of sustainable development for industry: a general framework. Process Saf Environ Prot 78(4):243–259CrossRefGoogle Scholar
  3. Barner HE, Davies DS, Szabo LJ (1977) Two-stage fluid bed reduction of manganese nodules. US Patent No. 4044094, 1977Google Scholar
  4. Biswas A, Chakraborti N, Sen PK (2009a) Use of process optimization and cost model for metal recovery from manganese nodules: the role of manganese recovery. In: Proceedings of the 8th (2009) ISOPE ocean mining, pp 124–130Google Scholar
  5. Biswas A, Chakraborti N, Sen PK (2009b) A genetic algorithm based multiobjective optimisation applied to a hydrometallurgical circuit for process optimisation. Miner Process Extr Metall Rev 30:163–189CrossRefGoogle Scholar
  6. Charles C (1990) Views on future nodules technologies based on IFREMER-GEOMONOD Studies. Mater Soc 14:299–326Google Scholar
  7. EPA Report (2009) Sustainable materials management. June 2009.Google Scholar
  8. Erdmann L, Graedel TE (2011) Criticality of non-fuel minerals: a review of major approaches and analyses. Environ Sci Technol 45:7620–7630CrossRefGoogle Scholar
  9. Fiksel J (2006) A framework for sustainable materials management. JOM 58(8):15–22CrossRefGoogle Scholar
  10. Graedel TE, Harper EM, Nassar NT, Reck Barbara K (2015) On the materials basis of modern society. PNAS 112(20):6295–6300CrossRefGoogle Scholar
  11. Halbach P, Fellerer R (1980) The metallic minerals of the Pacific Sea floor. GeoJournal 4(5):413–414CrossRefGoogle Scholar
  12. Ham K-S (1997) A study on economics of development of deep sea bed manganese nodules. In: Proceedings of the 2nd ocean mining symposium, pp 105–111Google Scholar
  13. Haque N, Norgate T (2013) Estimation of green gas emissions from ferroalloy production with life cycle assessment with particular reference to Australia. J Clean Prod 39:220–230CrossRefGoogle Scholar
  14. Haynes BW, Law SL, Maeda R (1982) Updated process flow sheets for manganese nodule processing. IC 8924, p 99Google Scholar
  15. Hein J (2012) Prospects of rare earth elements from marine minerals. Briefing paper 02/12, International Seabed Authority, New York seminar Feb 2012, pp 1–4Google Scholar
  16. Hekkert MP (2000) Materials management to reduce Green House Gas Emissions. Thesis, Ultrecht University. ISBN: 90-393-2450-6Google Scholar
  17. Hillman CT, Gosling BB (1985) Mining deep ocean manganese nodules: description and analysis of a potential venture. USBM IC9015. United States Department of the Interior, Bureau of Mines, Washington, DC, 19pGoogle Scholar
  18. Huijbregts MJ, Hellweg S, Frischnecht R, Hendriks HWM, Hungerbuhler K, Hendriks AJ (2010) Cumulative energy demand as predictor of the environmental burden for commodity production. Environ Sci Technol 44:2189–2196CrossRefGoogle Scholar
  19. IKARUS (1998) Datenbase Industry. Fraunhofer Institute for system and innovation research, KarlshruheGoogle Scholar
  20. International Aluminum Institute (2013) Carbon Foot print guidance document.…/fl0000169.pdf.. Accessed 8 Aug 2015
  21. International Council of Mining and Metals (2012) Trends in the Mining and Metals industry, Mining’s contribution to sustainable development. Accessed 19 Aug 2015
  22. Lenoble JP (1990) Future deep sea bed mining of poymetallic nodules. IFFREMER, Issy-les-Moulineaux Cedex, FranceGoogle Scholar
  23. Ligthart TN, Toon A (2012) Modeling of recycle in LCA. Accessed 12 Nov 2015
  24. Lorenz E, Graedel TE (2011) Criticality of non-fuel minerals: a review of major approaches and analyses. Environ Sci Technol 45:7620–7630CrossRefGoogle Scholar
  25. Matricardi LR, Downing J (1995) Manganese and manganese alloys. In: Kirk-Othmer encyclopedia of chemical technology, vol 15, 4th edn. Wiley, New York, pp 963–990Google Scholar
  26. Mayze R (1999) An engineering comparison of the three treatment flow sheets in WA nickel laterite projects. ALTA hydrometallurgy forumGoogle Scholar
  27. Mero JL (1965) The mineral resources of the sea. Elsevier, Amsterdam, p 312Google Scholar
  28. Mukherjee A, Raichur AM, Natarajan KA (2004) Recent developments in processing ocean nodules-a critical review. Miner Process Ext Metall 25:91–127CrossRefGoogle Scholar
  29. Norgate TE, Jahanshahi S (2010) Low grade ores—smelt, leach or concentrate. Miner Eng 23:65–73CrossRefGoogle Scholar
  30. Norgate TE, Rankin WJ (2000) Life cycle assessment of copper and nickel production. In: Proceedings, Minprex 2000, international conference of mineral processing and extractive metallurgy, Sept 2000, pp 133–138Google Scholar
  31. Norgate TE, Jahanshahi S, Rankin WJ (2007) Assessing the environmental impact of metal production processes. J Clean Prod 15(8–9):838–848CrossRefGoogle Scholar
  32. Nuss P, Eckelman MJ (2014) Life cycle assessment of metals: a scientific synthesis. PLoS One 9(7):e101298. doi: 10.1371/journal.pone.0101298 CrossRefGoogle Scholar
  33. Peng XD (2012) Analysis of the thermal efficiency limits for steam methane reforming of methane. Ind Eng Chem Res 51:16385–16392CrossRefGoogle Scholar
  34. Van Peteghem (1977) Extracting metal values from manganiferous ocean nodules. US Patent 4026773, 31 May 1977Google Scholar
  35. Rankin WJ (2011) Minerals metals and sustainability: meeting future material needs. CRC Press, Boca Raton, FL, pp 226–230Google Scholar
  36. Rankin J (2012) Energy use in metal production. In: High temperature processing symposium, Swinburne University of Technology: Presentation 1Google Scholar
  37. Roorda HJ, Hermans JMA (1981) Energy constraints in the extraction of nickel from oxide ores (II). Erzmetall 34(4):186–190Google Scholar
  38. Sen PK (2010) Metals and materials from the deep sea: an outlook for the future. Int Mater Rev 55(6):364–391CrossRefGoogle Scholar
  39. Sen PK, Das SK (2008) Sea bed processing status review for commercialization. In: Polymetallic nodule mining technology, proceedings of the workshop, International Sea bed Authority, Chennai, 18–22 Feb 2008, pp 153–167Google Scholar
  40. Siemens Sustainability Report (2012) Driving sustainability. Accessed 25 Aug 2015
  41. Soreide F, Lund T, Markussen JM (2001) Deep ocean mining reconsidered: a study of the manganese nodules deposits in cook island. In: Proceedings of the 4th ocean mining symposium, Szezecin, Poland, pp 88–93Google Scholar
  42. UNEP Report (2009), Critical metals for future sustainable technologies and their recycling potential. Öko-Institut e.V., July 2009Google Scholar
  43. UNEP Report (2011) Recycle rates of metals. Panel, International ResourceGoogle Scholar
  44. UNEP/SETAC Life Cycle Initiative (2011) Towards life cycle sustainability assessment. ISBN: 978-92-807-3175-0Google Scholar
  45. Van der Voet E, van Oers L, Nikolic I (2004) Dematerialization: not just a matter of weight. J Ind Ecol 8(4):121–137CrossRefGoogle Scholar
  46. Yasuhiro K, Koichiro F, Kentaro N, Yutaro T, Kenichi K, Junichiro O, Ryuichi T, Takuya N, Hikaru I (2011) Deep sea mud in the Pacific Ocean as a potential resource for rare earth elements. Nat Geosci 4:535–539CrossRefGoogle Scholar
  47. Zhang Y, Liu Q, Sun C (2001) Sulphuric acid leaching of Ocean Manganese nodules using phenols as reducing agents. Miner Eng 14:525–537CrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Indian Institute of TechnologyKharagpurIndia

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