4. MARINE NON-LIVING RESOURCES

4.1 Polymetallic Nodules (PMN) Programme

The Polymetallic Nodules (PMN) Programme is a national programme aimed towards assessment of nodules in the 1,50,000 sq. km area allotted to India in the Central Indian Ocean Basin (CIOB) and development of technologies for mining and extraction of metals from nodules. India as the first “Pioneer Investor” has to undertake different developmental activities for exploring and exploitation of polymetallic nodules towards fulfillment of the obligations relating to development and transfer of technology and training in the use of technology, etc. Ever since India attained this status in 1987, efforts were on survey and exploration, technology development for mining of nodules, extractive metallurgy and EIA studies. This programme consists of four major components viz., Survey and Exploration of nodule in the CIOB; Environmental Impact Assessment Study at the mine site; Development of technologies for mining of nodules and Extraction of metals.

Survey & Exploration

The Survey and Exploration endeavour is aimed at firmly establishing the nodule resource potential on the basis of progressive closer grid sampling and spot photographs. The abundance pattern vis-à-vis the geomorphology has been established along with upgradation of the resource evaluation techniques on the basis of one lakh photographs obtained from the mine site. India has already relinquished 30% of the surveyed area to International Seabed Authority (ISBA). Survey & Exploration in the Indian mine site was undertaken at a close grid of 5 km. in selected marginal blocks for validating the resource assessed for updating relative concentration and quality characteristics of the polymetallic nodules in the different pre-determined blocks. Towards relinquishment of balance 20% of the pioneer area to ISBA, part fulfilment of the obligations of the registered pioneer investor was finalised.

Environmental Impact Assessment Study

As a part of the ongoing Environmental Impact Assessment study, monitoring of various parameters in the identified areas was undertaken during a cruise to the same test and reference sites in the pioneer area to evaluate the extent of restoration and plume patterns, etc.

Technology Development - Mining:

Deep-sea technology and ocean mining group in the National Institute of Ocean Technology (NIOT) is responsible for the development of technology for mining of polymetallic nodules from the seabed and other underwater components. As a part of technology development for underwater mining, a crawler based system comprising a flexible riser using hydraulic drives with single stage positive pump, manipulator and crusher and collector was designed and integrated in the crawler with the technical participation of Institut for Konstruktion (IKS), University of Siegen, Germany. The complete integrated system was demonstrated at a shallow water depth of 410 m off Tuticorin coast successfully.

As a part of this joint collaborative programme, a design report on underwater mining system for manganese nodule mining from 6000 m water depth was prepared jointly by NIOT, Chennai and IKS, Germany and submitted to Department of Ocean Development, for mining nodules at the rate of 25000 tonnes per annum. The design reports and future project proposals were reviewed by a Committee at NIOT. The suggestions made by the Committee have been incorporated in the project proposal and revised. This revised project proposal is being processed for getting the requisite clearances from the Government. The main objective of this project is to develop and qualify it as an Integrated Manganese Nodule Mining System at 6000 m depth.

Technology Development – Metallurgy

A semi-continuous demonstration pilot plant to process 500 kg per day of polymetallic nodules to validate the process package developed for extraction of metal values from nodules at Hindustan Zinc Limited (HZL), Udaipur was commissioned and pre-campaign trials have been taken up. The Department collected 45 tonnes of nodules for this demonstration plant with the help of research vessel R.V.A.A. Sidorenko in addition to 80 tonnes already collected for this purpose. The demonstration campaigns will generate data for evaluation and validation of process package already developed. The first campaign is scheduled to commence by end of March 2002.

Semi-continuous pilot plant for extractive metallurgy at HZL, Udaipur

RRL (B) and HZL (U) are pursuing the R&D efforts for optimising the metal recovery/processing steps. National Metallurgical Laboratory (Jamshedpur) is carrying out R&D activities relating to recovery of Ferro-Manganese alloy from the waste generated by RRL process route.

Remotely Operable Vehicle (ROV)

A Remotely Operable Vehicle (ROV) has been successfully developed by Central Mechanical Engineering Research Institute, Durgapur (CMERI) as a part of the Polymetallic Nodule (PMN) Programme of the Department of Ocean Development (DOD). The ROV is capable of performing underwater survey operations at 200 metres water depth and could be operated at a maximum of 2 knots speed. It can carry a maximum payload of 60 kg. The ROV was successfully tested at 200 m water depth off Chennai coast using the vessel A.A.Sideronko during August 2001 jointly by CMERI and NIOT. Design improvements on the umbilical assembly and underwater camera to obtain better picture quality are being made, based on the results obtained from the last sea trials.

4.2 Benfan

Detailed bathymetric studies using hydrosweep system were taken up in the pre-determined blocks. Several channels were traced with this data. The data are being analysed to identify sites for the long core collection.