Ocean Technology Capacity Building in India
Oceans are a promising strategic frontier for the economic growth, water and food security for the global population which will require 30% more water, 40% more energy and 50% more food by 2030. About 40% of the world population live within 100km from the coastline which is dominated by a range of economic activities and hence needs to be protected from natural hazards. Ocean policies are being enacted by various countries for synergising the efforts towards sustained use of ocean resources through appropriate vision, technology, management, monitoring, and time-bound regulatory reforms. In India, understanding the potential need for ocean technology development, National Institute of Ocean Technology (NIOT) was started in 1993 at the Ocean Engineering Centre in the Indian Institute of Technology, Chennai. The mandate was to develop reliable indigenous technologies for sustainable harvesting of non-living and living resources, as well as develop knowledge base and institutional capabilities in India for management of ocean resources and development. Subsequently, NIOT was integrated with the Ministry of Earth Sciences (MoES), formerly Department of Ocean Development (DoD) in 2000 with a separate campus at Pallikaranai in Chennai. Over
the past 25 years, NIOT has built national capacity through technology development programs for exploring deep ocean minerals, harvesting renewable ocean energy, desalination, bio-prospecting; monitoring coastal hazards, coastal protection and observing Polar ecosystems. The facilities for effectively carrying out ocean research such as ships and test infrastructure are developed. The technologies developed were patented and subsequently transferred to the Indian industries in order to spur the ocean technology activities. The assimilated knowledge is being disseminated through scientific publications. The activities which are being carried out in the past 25 years, categorized into ocean resource exploration and ocean monitoring technologies is represented in Fig.1. Based on the capacity built over the period, NIOT continues its journey by executing various high technology projects and programs of societal importance.
NON-LIVING RESOURCES Deep Blue Minerals
The developments of the coastal and offshore mineral resources are complimentary for the industrial and economic growth. About 247, 1.82, 10.47 and 9.5 million tonnes of manganese, cobalt, nickel and copper are located in waters depths ranging from 5000 to 6000m as polymetallic nodules in the Central Indian Ocean Basin (CIOB), hydrothermal sulphides in the southern Indian Ocean and cobalt crusts in the Afanacy Nikitin sea mount area (Fig.2). For carrying out demonstration mining, India has been allocated an area of 75,000 km2 and 10,000 km2 in the polymetallic nodule and hydrothermal
sulphide sites respectively. Technologies for the exploration and exploitation of these deep ocean minerals are developed by NIOT.
After carrying out field demonstration of a crawler-based mining machine at about 500m water depth, development of a 6000m depth-rated demonstrative polymetallic nodule mining
Fig.1. Technology programs undertaken by NIOT
machine capable of being deployed from NIOT’s technology demonstration vessel Sagar Nidhi was taken up. The machine powered and controlled through the electro-optic umbilical is capable of crawling on the soft deep sea bed, collecting the polymetallic nodules, crushing and pumping them to the mother ship in the form of slurry through a 6000m vertical riser. Subsystem development and qualification are undertaken in phases before deploying the integrated mining system in the CIOB. In order to measure the shear and bearing strength of the deep sea bed before deploying the mining machine, a 6000m depth-rated in-situ soil tester is developed and qualified at 5462m water depth in the CIOB (Fig.3). For enabling deep ocean mineral exploration, a 6000m depth rated electric work class Remotely Operated Vehicle (ROSUB 6000) was developed and is being used for carrying out deep ocean mineral exploration in the polymetallic nodule site in the CIOB during 2010 and in the hydrothermal sulphides site at the Rodriguez Triple Junction in the Central Indian Ridge during 2013. The matured ROSUB6000 technology is transferred to the Indian industries for enabling deep ocean activities.
permanent magnet alternator suitable for Indian conditions is undertaken. Underwater current measurements carried out in Kadamtala in the Andaman Islands in 2018 revealed continuous water current potential of about 2.5m/s. India is a member of the International Energy Agency-Ocean Energy Systems (IEA-OES) Group and have taken up activities for fostering the growth of ocean renewable energy systems in the Asian region.
The increased production of natural gas from the domestically available hydrocarbon resources shall help reduce natural gas import dependence and to reduce greenhouse gas emissions. In the unconventional fossil hydrocarbon segment, it is estimated that approximately1684TCM of methane gas are sequestrated as gas hydrates in the continental settings in 100-300m below the sea floor at water depths ranging between 800-3000m. Large, highly saturated gas hydrate accumulations in the coarse-grained sand-rich depositional systems are located in the KG basin. For carrying out ground truth qualification and for enabling spatial quantification of the resource, NIOT is developing a 3000m depth rated wire-line autonomous coring system (ACS) which has the capability for taking gas hydrate bearing core samples up to 100m below the sea floor (Fig.5). A laboratory for synthesising gas hydrates is established and a
Fig.3 (a) Mining machine pumping tests (b) Crawler launched for
qualification (c) Soil tester (d) ROV ROSUB6000
Energy
In the offshore energy segment, NIOT is developing technologies for harnessing the ocean energy and unconventional gas hydrate resources. For measuring the wind potential at 20m elevation from the sea level, LIDAR-based data collection platforms are installed by NIOT and Ministry of New and Renewable energy (MNRE)-National Institute of Wind Energy in the Gulf of Kutch and Gulf of Khambhat during 2017. Studies on the commercial viability are undertaken for turbines of 3 MW capacities.
Subsequent to the demonstration of a wave energy plant based on the principle of oscillating water column at Vizhijam in Kerala, NIOT has developed and demonstrated a range of floating wave powered systems including a Backward Bent Ducted Buoy suitable for port navigation (Fig.4). Development of a 5kW gearless hydrokinetic turbine with slow-speed
Fig.4. LIDAR-based based platform in Gulf of Kutch.
numerical gas hydrate reservoir modelling and production simulation model IndHyd 1.0 for evaluating the spatiotemporal effectiveness of the depressurization-based methane gas production technique are also developed by NIOT.
Desalination
Securing adequate quantities of clean water to meet the needs of the growing population is a major challenge. Coastal communities are increasingly turning to the sea to meet their drinking water needs, while in inland there is a tendency for groundwater to become increasingly brackish over time. Based on the experiences gained by NIOT in the development of a single-point moored barge-mounted Ocean Thermal Energy Conversion (OTEC) plant attempted off-Tuticorin in 1000m water depths and the barge mounted desalination plant demonstrated off-Chennai (Fig.6), NIOT has designed and implemented Low Temperature Thermal Desalination (LTTD) plants of 100 m3/day capacities in the three Islands in the Union
Territory of Lakshadweep, where a long cold water is used to draw water from water depth around 300m using a high density polyethylene pipe. The plants which are operating over a decade have proved multiple socio-economic advantages including
health of the island community. Installing LTTD-based desalination plants in six more islands of India is underway (Fig.7). Design of an open-cycle OTEC-powered LTTD-based desalination plant capable of producing fresh water of 100m3/
day and electricity is undertaken in the Kavaratti Islands. The LTTD-based technology for utilization of the condenser reject heat from thermal power plants is demonstrated in the coastal North Chennai thermal power station and is being extended to similar plants.
LIVING RESOURCES Bio-prospecting
Marine bio-prospecting is essential for pursuing human health, offering sustainable supply of high quality food, new industrial products and developing sustainable sources of energy alternates to conventional hydrocarbons. Based on engineering techniques, efforts are undertaken to bridge the widening gap between the demand and supply of seafood including crab fattening, lobster fattening, fish aggregation devices, and artificial reefs since 2003. In order to identify effective fish aggregation methods, multi-point moored open sea cages (Fig.8) made of high density polyethylene of diameters larger than 9 m capable of withstanding turbulent sea states are developed and demonstrated by NIOT.
Culturing commercially important marine finfishes were demonstrated with encouraging results in the North Bay in the Andaman Islands, Olaikuda in Tamil Nadu and Kothachathram in Andhra Pradesh. Large scale cultivation systems such as bubble column photo-bioreactor, tubular photo-bioreactor and raceway pond systems are developed and suitable culture conditions were optimized for the mass culture of marine microalgae, and the extracted lipids from the mass culture ventures are trans-esterified into biodiesel.
For fostering the studies on the applications of the deep sea piezophilic micro-organisms in the health and medical sectors, a deep ocean microbial sampling and incubation system capable of bringing the deep-ocean micro bio-resources to the surface and incubating them by maintaining their ambient pressure is established in NIOT (Fig.9). The Atal Center for Ocean Science & Technology for Islands established
Fig.6. Barge mounted desalination plant
Fig.7. Desalination plant in Agatti Island and proposed locations
in Port Blair is established in 2018 with advanced research facilities.
OCEAN HAZARD MITIGATION AND ECO-SYSTEM PROTECTION
Ocean State Monitoring
The Indian maritime zone which is dominated by a range of economic activities is being perennially plundered by a fury of tropical cyclones. The tsunamigenic zones in the Andaman-Sumatra trench and the Makran coast pose an ever present tsunami threat to the long coastline. The Indian Ocean observational network established by the MoES under the Indian Ocean Observation System is configured for real-time and delayed-mode coastal and offshore observations facilitating data assimilation and real-time validation of the operational nowcast/forecast of the ocean variables in and around the Indian Seas. The moored buoy network includes the NIOT-operated Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction mooring network (RAMA) and the Ocean Moored buoy Network for northern Indian Ocean (OMNI) spanning between 63°E to 93°E and 6°N to 20°N (Fig.10) for collecting the meteorological, water surface and subsurface parameters; as well as the tsunami water level data. The collected data is transmitted to the NIOT Mission Control Center located at NIOT in Chennai and
to the Indian Tsunami Early Warning Center (ITEWC) in INCOIS, Hyderabad. Since inception, the networks have detected more than 41 cyclones and 11 water level change events used to monitor tsunami waves. The data acquired during various events serve as important inputs to various agencies including the Indian Meteorological Department (IMD) and for understanding the Indian Ocean dynamics essential for improved modeling of the evolution of the seasonal monsoon and cyclones.
The tsunami buoys are moored at strategic locations close to the Andaman-Sumatra subduction fault in the Bay of Bengal and Makran fault in the Arabian Sea (Fig.11). During a tsunami event, the sea level inputs from the tsunami buoys serve as critical inputs to the Indian tsunami early warning center’s pre-run scenario database which computes the tsunami travel times and wave run-up wave heights, which are essential for the timely generation and dissemination of the tsunami advisories.
Fig.9. Deep ocean microbial sampling and incubation system
Fig.10. Moored surface buoys deployed in Indian waters
Shoreline Protection
Healthy coastal ecosystems provide protection from the natural hazards, coastal erosion and rising sea levels. The coastal erosion due to the cyclone events and anthropogenic activities degrades the coastal infrastructure and livelihoods. NIOT has carried out siltation and dredging studies for various ports and also carried out detailed bathymetric surveys for studying the changes in hydrodynamic and sedimentation pattern in the Gulf of Khambhat. Coastline-specific solutions based on the sedimentation process and littoral drift are undertaken by NIOT in various Indian ports. In Kadalur-Periyakuppam village near Chennai, submerged shore parallel offshore dykes of 200m lengths made of geo-synthetic material filled with fine sand are being installed over 1.2 km in order to protect the beach from severe erosion which affected the shoreline during the recent tropical cyclones (Fig.12). By keeping the structure submerged, smaller waves are allowed to cross over to the shorefront facilitating normal sediment transport. The Indian shorelines which are sensitive to erosion are being monitored and measures initiated in coordinated with the respective local state administration. A wave atlas is published by NIOT in 2014 provides wave parameters at any user selected location which is essential for long term planning purposes.
The coastline of historical Puducherry in the east coast of India suffered severe coastal erosion due to natural causes and reorientation of the coast due to the port breakwaters. An integrated long-term solution for protection and restoration of beach is undertaken for which construction of artificial reef is undertaken. The formation of the beach after carrying this measure is shown in Fig.13.
Coral Reef Monitoring
Corals are diverse shallow marine ecosystems that play an important role as a habitat for organisms in their environs supporting a vast diversity of coastal animal and plant species. During the last few decades, due to global warming, the genetic heritage of the coral ecosystems is reported to be at risk. The corals of the Andaman Island, which has the richest coral diversity among the Indian reef were victims of the thermal stress due to the elevated temperatures. Coral reef surveys were conducted at the North Bay, Chidiyatapu, Jolly Buoy, Red skin and Grub Islands of the south Andaman district using the shallow water/Polar remotely operated vehicle PROVe developed by NIOT (Fig.14) as a part of the unmanned under-water vehicle program.
Polar Oceans Studies
The interactions between the global oceans, atmosphere and cryosphere influence the climate, biogeochemical cycles, biological productivity and the climate change on a global scale. During the 34thIndian Scientific Expedition to Antarctica (ISEA) in2015, the PROVe was deployed in the Priyadarshini Lake in the Eastern Antarctica and in the new Indian ice shelf barrier region using the vessel Papanin (Fig.15). The physical properties of the ice shelf water were logged using the PROVe onboard sensors, and the sonar images revealed ice shelf thickness of >62m.
The first Indian multi-sensor moored observatory, IndArc, for enabling long-term in-situ data collection comprising of physio-chemical and oceanographic sensor suite was deployed by NIOT and MoES-National NCAOR in Kongsfjorden (78° 57" N, 12° 01" E) in the Arctic waters in the 180m isobath (Fig.16) east of Ny-Ålesund and about 1100 km from the North Pole. The sensors are acquiring the data since July 2014 support ecosystem modeling of the glacial runoff and fresh water plumes that emerge from beneath the tide water glaciers. Acoustic sensor arrays are also deployed in the Arctic since 2015 for measuring the ambient noise.
TECHNOLOGY PRODUCTS
In order to spur the growth of ocean technology activities in India, technologies developed by NIOT including the Remotely
Fig.12. Dyke laid off-Kadalur Periyakuppam.
Fig.13. Installation of artificial reef in Puducherry
Fig.14. PROVe in South Andaman coral reef expedition
Fig.15. PROVe deployed in Antarctica waters
Operable Vehicle, Autonomous Underwater Profiling Drifter, tsunami bottom pressure recorder (Fig.17) and wave powered navigational buoys are patented and subsequently transferred to the Indian industries. The developments have helped in attaining technological self-sufficiency and helps in import substitution.
INFRASTRUCTURE AND FACILITIES
In order to carry out calibration of the underwater acoustic systems the acoustic test facility (ATF) is established in NIOT. The hyperbaric test facility is extensively used to qualify the deep ocean systems for external pressures up to 900 bar (Fig.18). The NIOT vessel fleet comprises of Sagar
FUTURE PROGRAMS
With the extended Exclusive Economic Zone, India’s Ocean jurisdiction will be equal to its land area. NIOT shall continue its journey in developing indigenous, reliable, world-class technologies for the exploration, sustained utilization of ocean resources and provide technical services for management of ocean environment. Based on the capacity built over the period, NIOT has initiated various high technology projects under the Deep Ocean Mission, programs of societal importance and expansion of research infrastructure. They include development 6000m depth-rated 3-crew human submersible with mission specific scientific sensors and payloads, autonomous under-water vehicles, higher capacity wave energy and hydro-kinetic systems, protection of coastal areas from littoral drifts, Open ocean farms with submerged platforms/submerged long lines for shellfish culture and submerged cages for finfish culture, higher capacity desalination plants with cogeneration of power.
Acknowledgements: The work reported is due to the support of all NIOT engineers and scientists and the author is grateful for their support. The preparation of the manuscript was possible with the excellent support from Dr. Vedachalam, for which I am thankful.
Director, National Institute of M. A. ATMANAND
Ocean Technology, Ministry of Earth Sciences, Chennai, India E: [email protected]
Fig.17. Technological products developed in-house
Fig.18. Acoustic test tank and hyperbaric testing facility
Fig.19. NIOT vessel fleet
