(Phosphoric acid plant: Image Courtesy PPL)

 

The Heavy Water Board (HWB) intends to set up a Rs. 273.33-crore project for extracting uranium and other rare earth elements from wet phosphoric acid (WPA) produced at Paradeep Phosphates Limited (PPL), a privatized fertilizer enterprise.

HWB document says: “The proposed Rare Material Recovery (RMR) Plant has been declared as strategic by Government of India. Recommendation of Secretary DAE (Department of Atomic Energy) and approval of NSA (National Security Advisor)” have been obtained. 

It adds: “The production of Rare Material will make our country self-reliant, which will enable sustaining various activities of DAE.”

This would be the country's second commercial-scale uranium extraction (UEP)/RMR plant for segregating this nuclear fuel from fertilizer-grade phosphoric acid. The first one, also at Paradeep in Odisha, is being set up at Indian Farmers Fertiliser Cooperative Limited (IFFCO)’s phosphatic fertilizers complex at a cost of Rs 285 crore. HWB secured environmental approval for clearance for the 85-tonnes per annum (tpa) UEP in May 2014.

Another UEP, which was conceived before the PPL one, appears to be on the backburner. It would be set up at Haldia fertilizer facility of Tata Chemicals Limited.  

UEP would be based on solvent extraction technology developed by HWB using in-house solvents like TOPS-99 & TOPS-03 and TOPS-08. The design processing capacity of this plant is 100 cubic meters per hour (m3/hr) of feed WPA with a RM content averaging 105 parts per million (ppm). The end product of this facility will be yellow cake.

Apart from HWB, DAE, flagship R&D arm, Bhabha Atomic Research Centre (BRAC) has participated in development of indigenous technology for extraction of uranium from WPA. 

As put by BARC expert Harvinderpal Singh in an articile published in 2007, “Depending on the nature of phosphoric acid, a particular type of solvent is needed. BARC has recently developed a novel solvent extraction process based on Di-Nonyl Phenyl Phosphoric Acid (DNPPA) which has been patented.”

The article captioned ‘Development of Innovative Processes for the Separation of high Purity Uranium from Phosphoric Acid, says: “another process has been developed and patented using currently available indigenous industrial solvents for extraction from ~28% P2O5 weak acid (WPA).”

India is a late entrant in this realm of production of uranium from secondary sources, the primary source being conventional mining of uranium from the earth. Commercial-scale UEPs came up in the United States in the seventies. Later, other countries such as China and Canada also established UEPs. 

India is following what International Atomic Energy Agency (IAEA) calls as policy-driven extraction of uranium from WPA. Under this model, the production cost is borne by the Government and not influenced by global uranium prices. 

According to a report ‘Uranium 2014: Resources, Production and Demand’ published jointly issued by IAEA and OECD Nuclear Energy Agency in September 2014, the potential to expand the unconventional uranium resource base is strongly tied to the ability to bring these resources into production. This will depend on i) market conditions, notably for the commercial recovery of phosphate reserves, since these determine the underlying economics of by-product uranium recovery; and ii) changing policy, notably to require uranium and other critical resources such as rare earth elements to be extracted for strategic and sustainability reasons rather than on a commercial basis. Policy drivers might include the need to enhance the security of uranium supply to the national nuclear fuel cycle or to reap the environmental benefits of extracting uranium from phosphoric acid rather than by conventional mining, along with minimising the already very low amounts of uranium contained in fertilizer products.

The Report says that a hybrid situation (market and policy driven scenario) may, however, be the most sustainable scenario over the long term. The need to combine fuel security to the utility company with commercial viability to the phosphate company and to align these requirements with the equally significant role of phosphates in providing food security could drive new business models.

It continues: “One benchmark in Brazil has already been set for this scenario, the Santa Quitéria greenfield joint venture between the government company, Indústrias Nucleares do Brasil (INB), and Galvani phosphates, with a prime customer Eletrobras, owner of the national nuclear power operator, Eletronuclear. This project will produce both yellow cake and diammonium phosphate (DAP) in a single integrated process, thus spreading business risk across both phosphates and uranium.”

It remains to be seen whether any of three greenfield DAP projects proposed in India would follow the hybrid revenue model or set up an integrated project as a joint venture with DAE.