Context: Mumbai-based TEMA India has been entrusted with testing the equipment required for upgrading of depleted heavy water, a crucial requirement for Pressurised Heavy Water Reactors in India. It is a significant step towards speeding up the operationalisation of nuclear power plants.
Relevance of the Topic: Prelims: India’s 1st private test facility for Heavy Water Upgrade; Heavy Water; Pressurised Heavy Water Reactors.
India’s 1st Private Test Facility for Heavy Water Upgrade
- Until now, the assembling and testing of equipment for heavy water upgrade were centralised and done by Bhabha Atomic Research Centre (BARC).
- TEMA India has inaugurated its test facility at Achchad in Palghar district, Maharashtra, where it will manufacture equipment such as distillation columns and integrate and test them before sending them to reactor sites for installation.
- The facility was designed and built by TEMA India’s nuclear vertical under technology transfer from BARC and a ‘purchase order’ from Nuclear Power Corporation of India Ltd (NPCIL).
Significance:
- Single-point solutionfor upgrading heavy water:
- Till now, the distillation columns and modules were manufactured by other vendors, and then assembled and tested by BARC. The entire process took 7-8 years.
- The decentralisation will reduce the time period by at least one to two years, and thus speeden up the operationalisation of nuclear power plants.
What is Heavy Water?
- Heavy water (D2O) is a form of water (H2O) with deuterium (a heavier isotope of hydrogen), instead of regular hydrogen.
- It is used as a coolant as well as moderator for slowing down fast-moving neutrons during a chain reaction essential for sustaining the nuclear fission process.
- D2O needs to be 99.9% pure for working efficiently. With time it gets contaminated with light or regular water, thus requiring the depleted D2O to be upgraded back to 99.9% using a distillation process.
TEMA India has dispatched the first batch of tested distillation column sections for deployment at a unit of the Rawatbhata Nuclear Power Plant (RAPP-8) in Rajasthan, which is scheduled to go critical by December 2025.
Pressurised Heavy Water Reactor:
- Fuel: Natural Uranium (unenriched)
- Moderator and Coolant: Heavy water is used as both moderator and coolant.
- Cooling System: Uses a combination of heavy water and light water to cool the reactor. Heat is transferred to a secondary loop, which then generates steam to drive turbines.
- Control Rods: Boron or Cadmium control rods.
- Fuel requirement: Annual requirement of fuel (UO2) of a 700 MW PHWR (at 85% Capacity Factor) is about 125 tons.
- Advantages: Uses natural Uranium fuel, produces less high-level radioactive waste, and operates at lower pressures compared to some other reactor types.
India’s Nuclear Energy Generation Target
- India has set its eyes at achieving 100 GW of installed nuclear energy capacity by 2047.
- There are 24 nuclear reactors operational in India with an installed capacity of 8780 MW.
- The government had approved construction of 10 more nuclear reactors in 2015- of which one has come onboard, while the rest (with a combined capacity of 13.6 GW) are under construction.
- The immediate target is to achieve 22.4 GW of installed capacity by 2032.
- The government has also launched a 20,000-crore Nuclear Energy Mission to develop Small Modular Reactors.