Patent Number: 
Section: claims

1. A nuclear fission reactor comprising:a reactor vessel;a fission region within the reactor vessel;a fertile blanket region in the reactor vessel, the fertile blanket region being in hydraulic communication with the fission region and neutronic communication with the fission region;a solution, received in the fission region and the fertile blanket region, the solution including a first fissile nuclear fission fuel material dissolved in neutronically translucent liquid carrier material; anda solid, undissolved fertile nuclear fission fuel material in the fertile blanket region and in direct physical contact with the solution, the fertile nuclear fission fuel material being transmutable into a second fissile nuclear fission fuel material, the second fissile nuclear fission fuel material being diffusible directly into the solution within the reactor vessel. 2. The nuclear fission reactor of claim 1, wherein solubility of the second fissile nuclear fission fuel material in the neutronically translucent liquid carrier material is greater than solubility of the fertile nuclear fission fuel material in the neutronically translucent liquid carrier material. 3. The nuclear fission reactor of claim 1, wherein the fertile nuclear fission fuel material is substantially insoluble in the neutronically translucent liquid carrier material. 4. The nuclear fission reactor of claim 1, wherein the fertile nuclear fission fuel material is provided in a form chosen from granular form, wire form, plate form, and foam form. 5. The nuclear fission reactor of claim 1, wherein the solution and the fertile nuclear fission fuel material are distributed homogeneously in the reactor vessel. 6. The nuclear fission reactor of claim 1, wherein the solution and the fertile nuclear fission fuel material are distributed heterogeneously in the reactor vessel. 7. The nuclear fission reactor of claim 1, further comprising a plurality of nuclear fission fuel pins received in the reactor vessel, each of the plurality of nuclear fission fuel pins having a first axial end and a second axial end. 8. The nuclear fission reactor of claim 7, wherein a first portion of at least one nuclear fission fuel pin is disposed in a fission region of the reactor vessel and at least a second portion of the at least one nuclear fission fuel pin is disposed in a fertile blanket region of the reactor vessel. 9. The nuclear fission reactor of claim 7, wherein:the solution is distributed throughout each of the plurality of nuclear fission fuel pins; andthe fertile nuclear fission fuel material is received in first and second fertile blanket zones disposed toward the first and second axial ends, respectively, of each of the plurality of nuclear fission fuel pins. 10. The nuclear fission reactor of claim 1, further comprising:a plurality of fertile blanket modules disposed in the fertile blanket region, the fertile nuclear fission fuel material being received in the plurality of fertile blanket modules. 11. The nuclear fission reactor of claim 1, further comprising:at least one heat exchanger element in thermal communication with the solution. 12. The nuclear fission reactor of claim 11, wherein the at least one heat exchanger element is immersed in the solution. 13. The nuclear fission reactor 11, further comprising:an annulus disposed in the reactor vessel adjacent the at least one heat exchanger element such that natural circulation of the solution is establishable through the at least one heat exchanger element and around the annulus. 14. The nuclear fission reactor of claim 1, wherein a first concentration of the second fissile nuclear fission fuel material in the fertile nuclear fission fuel material is greater than a second concentration of the first fissile nuclear fission fuel material in the neutronically translucent liquid carrier material. 15. The nuclear fission reactor of claim 1, wherein thefission region is located toward a centralized region of the reactor vessel;and the fertile blanket region is located toward a peripheral region of the reactor vessel. 16. The nuclear fission reactor of claim 15, wherein the reactor vessel is cylindrical. 17. The nuclear fission reactor of claim 16, wherein the peripheral region of the reactor vessel includes a radially peripheral region. 18. The nuclear fission reactor of claim 15, wherein the peripheral region of the reactor vessel includes an axially peripheral region. 19. The nuclear fission reactor of claim 15, further comprising:a plurality of fertile blanket modules disposed in the fertile blanket region toward a radial periphery of the reactor vessel, the fertile nuclear fission fuel material being received in the plurality of fertile blanket modules. 20. The nuclear fission reactor of claim 1, wherein the fission region does not contain the undissolved fertile nuclear fission fuel material. 21. The nuclear fission reactor of claim 1, wherein diffusion of the second fissile nuclear fission fuel material directly into the solution occurs at the point of direct physical contact of the solution and the fertile nuclear fission fuel material and without the second fissile nuclear fission fuel material leaving the nuclear reactor.