Open nuclear fuel cycle

Fig. 2. Schematic illustration of the ideal open nuclear fuel cycle (NRC 2003). In this case, there is no reprocessing. Interim storage may last for tens of years so that the heat and radioactivity are much less prior to handling and final disposal. The spent fuel still contains fissile nuclides, such as 235U and 239Pu (generated by neutron capture reactions with 238U).

High-level waste (HLW), intermediate-level waste (ILW), and low-level waste (LLW) are produced at all stages of the nuclear fuel cycle as well as in the non-nuclear industry, research institutions, and hospitals. The nuclear fuel cycle produces liquid, solid, and gaseous wastes. Moreover, spent nuclear fuel (SNF) is considered either as a source of U and Pu for re-use or as radioactive waste (Johnson Shoesmith 1988), depending on whether the closed ( reprocessing ) or the open ( once-through ) nuclear fuel cycle is realized, respectively (Ewing, 2004). 

Proliferation. Nuclear-fuel-cycle operations leave open the possibility of improper access to fissile material through theft or diversion. Proliferation can be addressed through near-term measures designed to improve the proliferation-resistance of current nuclear reactor operations and through long-term research to explore proliferation-resistant designs (PC AST, 1999). 

Mining and ore processing. The nuclear fuel cycle is the cycle of uranium in the process of producing electricity via nuclear power plants. Uranium is mined in a number of countries in both open pit and underground mines. The ore undergoes several processing operations and conversions before it can be used in the reactors. 

Nuclear fuel cycle depicting the three available strategies once-trough fuel cycle, modified open cycle and closed fuel cycle. (From Paviet-Hartmann, P. 2012. Overview of the international R D recycling activities of the nuclear fuel cycle. International Journal on Nuclear Safety and Simulation, 3 267-275.)... 

FIGU RE 1.13 The main fuel cycle types the open fuel cycle (once through), the wait and see, and the closed fuel cycle (including reprocessing of the spent fuel). (Adapted from International Atomic Energy Agency, Nuclear fuel cycle information system, A directory of nuclear fuel cycle facilities, 2009 Edition IAEA TECDOC 1613, IAEA, Vienna, Austria. With permission.)... 

For the addressed concepts of small reactors without on-site refuelling. Chapter 5 reviews the fuel cycle options and associated institutional issues, provides an assessment of material balance characteristics in once-through and closed fuel cycles, and outlines the possible role of small reactors without on-site refuelling in making a transition from open to closed nuclear fuel cycle. This chapter also summarizes the features of small reactors that could facilitate their deployment with outsourced fuel cycle services. 

Possible role of small reactors without on-site refuelling in the transition from an open to a global closed nuclear fuel cycle... 

Nuclear Fuel-Cycle Requirements. There are two t)q)es of nuclear fuel cycles once through (open) and recycle (closed). The AHTR, VHTR, and MSR can be operated in eiftiermode while the LFR and GFR require a closed fuel cycle. With a once-through fuel cycle, the fuel is made with enriched uranium and the spent nuclear fuel (SNF) is a waste. With a recycle fuel cycle, the SNF is chemically processed to recover fissile materials that are used to produce new fuel. 

We open with a concise introduction on the sources of uranium in nature and its main physical, chemical, and nuclear properties and then briefly discuss the chan-istry of uranium and its compounds with phasis on those that play an important role in uranium processing, namely, in the uranium fuel cycle. As we are concerned with the modem analytical chemistry of uranium, we present the foremost analytical techniques that are used nowadays to characterize uranium in its different forms. 

Then, the dynamic response features of a transition from an open to a global closed fuel cycle based on symbiosis among near-term and longer-term nuclear power plant (NPP) concepts are outlined, and the issues for a smooth transition are highlighted. 

These three crucial departures in approach from the historical open cycle, economy of scale, LWR-form of nuclear energy permeate all elements of the STAR reactor and fuel cycle concept. 

In his prescient plenary speech On the nature of nuclear power and its future [1] at the GLOBAL 93 conference. Wolf Hafele compared the technical, institutional, and social opportunities for a second wave of nuclear deployments to those which brought about the Industrial revolution. He argued that the first wave of nuclear deployments - for electricity production and with an open fuel cycle - was destined to saturate at under 400 GWe global deployment because ... 

The BMN-170 concept opens the possibility of using these plants in multi-component structures suitable for nuclear power. The main tasks for a fast reactor are to provide effective closing of the fuel cycle for U and Pu and to expand breeding of nuclear fuel. 

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