Method for monitoring ore grade of an uranium bearing mixture

This patent describes a system for measuring the concentrations of a uranium-235 fluid mixture. The system consists of: (a) a holding tank; (b) a first valve through which the fluid mixture passes into the holding tank; (c) a float within the holding tank; (d) means coupled to the float for closing the first valve when the fluid level of the fluid mixture reaches a predetermined level; (e) an activation cell having a hollow inner portion; (f) a second valve which is opened to allow the fluid mixture to flow from the holding tank into the inner portion of the activation cell; (g) a continuous fast neutron source located within the activation cell for continuously irradiating the fluid mixture within the activation cell with fast neutrons; (h) a counting cell having a hollow inner portion into which the fluid mixture flows after having been irradiated with fast neutrons in the activation cell; (i) a circular array of neutron counters located within the counting cell; (j) a third valve which is opened to allow the fluid mixture to discharge from the counting cell; (k) a fourth valve which is opened to allow the fluid mixture to reenter the activation cell; and (l) means for continuously pumping the fluid mixture so as to recycle the fluid mixture through the third and fourth valves, the activation cell, and the counting cell