Mastering technology and production of heavy water — the key material needed to operate India’s indigenous nuclear reactor system — is a complex scientific and engineering assignment not many countries can tackle. Yet India had to meet this challenge for heavy water is the mainstay of the country’s nuclear power programme and is also valuable for industrial development.
In the early 70s, India was accused by the West of ‘stealing’ heavy water from Canada. The US and its allies imposed sanctions on India after the first nuclear test at Pokhran in 1974. When India was scurrying around the world for meagre quantities of heavy water, the West was in a denial mode, and Canada violated terms of collaboration for setting up a heavy water plant in India. Today, however, India has emerged as the largest producer of high quality heavy water in the world. Heavy water from India is being sought by South Korea, China and even by some US research bodies, for its quality and price.
To put the phenomenon in the words of Chairman and CEO of the Heavy Water Board (HWB), A.L.N. Rao, “Dr [Homi] Bhabha’s dream of producing cheapest heavy water to not only meet our requirement but also export has been effectively realised by the HWB.”
The journey of heavy water, from the production of its first drop at Nangal in 1962 to its first export in 1998, has been an arduous one — a revolution of sorts. The beginnings were modest. But the dedication of a highly trained staff has brought the big results. There were two distinct phases for the development of this technology: after the startup project for heavy water production failed post-Pokhran I, the first generation heavy water plants were left to rely on indigenous capability. Some of the first-generation plants were based on bi-thermal hydrogen sulphide-water exchange technology. But after the initial experience, plants based on mono-thermal NH2-H2 exchange process were built with foreign assistance.
The technical competence generated from design, construction and commissioning of these plants resulted in a sizeable quantum of industrial operation skills. In what might be described as a higher phase, the second generation plants were built with larger capacities and construction was taken up using indigenous design and engineering capabilities.
At present, heavy water production capacity in India is over 500 ton. The production takes place at six plants, situated at Baroda and Hazira (Gujarat), Kota (Rajasthan), Manuguru (Andhra Pradesh), Thal (Maharashtra) and Talcher (Orissa). Of late, the Talcher plant has stopped production due to the stoppage of work at an associated fertiliser plant. However, its infrastructure is being used for research and development.
According to Rao, “On moving from concept to commissioning and then to consolidation, we have increased the production of heavy water more than the rated capacities. No less significant, we have reduced specific energy consumption considerably. We have scaled new peaks in the areas of productivity, capacity utilisation, energy conservation, safety and environmental protection.”
Significantly, HWB is advancing further to activities of diversification to meet the emerging needs of the second phase of India’s nuclear programme. Among the latest achievements are commissioning of Boron enrichment plants at Talcher and Manuguru and Elemental Boron Plant at Manuguru.
A bright, new vista has opened up and is pushing HWB’s creative work to a new high. “With the confidence gained in the solvent extraction process of rare metal recovery from wet phosphoric acid at bench scale, a Technology Demonstration Plant is being set up. This will give additional confidence to the fertiliser industry that there won’t be any change in the characteristics of phosphatic fertiliser, after the rare metal is recovered from phosphoric acid,” says Rao.
The HWB has capped these achievements by entering into an MoU with external agencies to transfer Flue Gas Conditioning Technology, which has been patented by the HWB.