Chemistry in near-critical and supercritical water for the generation IV CANDU reactor concept

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The "Generation IV" CANDU reactor is a conceptual design for a novel, extremely energy-efficient  advanced reactor that would come on line in 2025.  The Gen IV concept would produce super-critical water at temperatures as high as 625°C to generate electricity, hydrogen and district heating.   The use of super-critical water to carry heat from the reactor core to the turbine will generate much more extreme water chemistry conditions than those used in current CANDU design, which operates from 250 to 310°C.  The long term viability of the Gen IV CANDU concept depends on the ability of designers to predict and control water chemistry to minimize radionuclide transport and subtle corrosion effects. This proposal seeks funding for a collaborative project that will use a state-of-the-art conductance system, developed at the University of Delaware and now moved to Guelph, to determine ionization and association constants for simple acids, bases and metal salts under near-critical and super-critical conditions (300 to 400°C, and 30 MPa).  The conductance apparatus is an extremely specialized piece of high-precision equipment, one of only two instruments with this capability in North America.  The project includes the upgrading and calibration of the equipment for improved operation in the supercritical region, measurements on several acids, bases and salts relevant to Gen IV steam generator chemistry, and the development of equations to predict the behaviour of aqueous species under these extreme conditions.  This pre-competitive research on Gen IV reactor concept, will advance North American effectiveness in the international competition to produce a Gen IV reactor compatible with Canada's expertise and CANDU experience. The short term benefits are (i)fundamental understanding of SCWR chemistry fundamentals and (ii) instrumentation for basic research on near-critical and super-critical systems. Long term benefits are the leadership in manufacturing technology if the reactor is developed in North America, significant reduction in green house gases,  and the energy savings associated with 44% efficiency and the co-generation of hydrogen.