4E ANALYSIS OF CONVERTING A HEAVY WATER REACTOR TO A LIGHT WATER REACTOR

Abstract

This paper presents a comprehensive analysis of the modifications required to convert a heavy water reactor (HWR) to a light water reactor (LWR), with specific focus on the IR-40 research reactor design. The conversion process is examined from technical, thermohydraulic, and economic perspectives, providing a holistic understanding of the challenges and opportunities involved. The thermohydraulic analysis reveals significant differences in heat transfer characteristics, flow behavior, and thermal limits between heavy water and light water systems, necessitating careful redesign of cooling systems and operating parameters. A novel pinch analysis methodology is applied to optimize heat exchanger networks and minimize energy consumption in the converted system. The economic assessment indicates that conversion costs range from $65-200 million depending on the approach taken, with a half-power (20 MWt) conversion representing the most balanced option at $85-140 million. Comparative analysis with international reactor conversion projects validates the proposed methodology and cost estimates. While the conversion does not present a positive financial return based solely on operational savings, it provides a path forward those balances nonproliferation objectives with the preservation of valuable nuclear infrastructure. This analysis offers valuable insights for similar conversion projects worldwide, contributing to global efforts to reduce proliferation risks while maintaining the beneficial applications of research reactors.