Modeling Operational Parameters for Uranium Dioxide Production Reactor through Uranium Trioxide Reaction Using Hydrogen

This article shows the modeling of a uranium dioxide production reactor using COMSOL Multiphysics software program in its 4.3b version. The model was made using 3 kinds of studies: momentum, heat and mass transport, in order to determine the influence of the most important operational parameters: UO3 reaction rate, composition and flow of the reduction gas, the initial temperature reactor and the reducing gas. The operational parameters evaluated were the followings: constant gas flow of2.5 L/min, initial hydrogen concentration of 0.25, 0.50 and0.75 M, and initial temperature of 400°C. The obtained results allow to conclude that under these working conditions, uranium dioxide is obtained virtually instantaneous and, with concentrations close to 0.5 M H2 in the reducing gas, the process can operate continuously and autogenously, without applying additional energy and temperatures around 600°C.

Recovering Scrap Anode Copper Using Reactive Electrodialysis

Despite functioning without major operational problems—copper electro-refining does not allow complete use of copper anodes, peaking at 85% of the copper anode in weight. Consequently, the remaining 15% of scrap copper must be recirculated into the copper smelting. The use of reactive electrodyalysis is a system capable of continuously electro-refining scrap, by using a stainless steel basket and a cationic exchanging membrane in order to increase production of copper cathodes at the same percentage;it currently today returns to the copper smelter. In terms of specific energy consumption, this process would use between 3 and 4 times the value of normal electro-refining.

Modeling Operational Parameters of a Reactive Electro-Dialysis Cell for Electro-Refining Anodic Scrap Copper

This work will create an electro-dialysis cell model that has the purpose of refining anodic scrap copper—an element that currently must be returned to the copper conversion process. The cell modeling is based on Ohm’s Law, while the resulting copper deposit morphology is studied through the thickness of the layer deposited on the surface and the electric current lines traced from the anode to the cathode. The use of the model demonstrated that it is possible to effectively predict the specific energy consumption required for the refinement of the anodic scrap copper, and the morphology of the cathode obtained, with a margin of error of 9%.

Design and Analysis of a Metallic Uranium Reactor Type-Pump Using the Magnesiothermy Process

This paper shows a methodology to obtain metallic uranium through a magnesiothermy process. Chile has two experimental reactors operated by the “Chilean Nuclear Energy Commission” (CCHEN). One is 5 MW and the other is 10 MW. In order to fulfill international agreements about nuclear energy for testing purposes of these reactors, CChEN purchased 19.9% enriched uranium hexafluoride, also known as the limit of Low Enriched Uranium (LEU). Due to the capacity of these reactors, they need high-density uranium compounds for their fuel, in order to work with LEU. For this reason, the uranium needs a previous conversion into metallic uranium. The conversion laboratory carried out experiences for reduction of UF4 with Mg. The main purpose of this study was to analyze the operating conditions under which the reduction reaction takes place, the designed method and the equipment and materials used. The raw material used was dehydrated UF4, prepared by electrolytic reduction and commercial purity Magnesium. The reaction took place in a cylindrical reactor made of low alloy steel, with a conic section in the lower part. The internal zone was coated with a 2.5 cm thick layer of CaF2. The process started by applying external heating, according to a heating program, developed specially for this purpose. The reduction reaction took place starting at 650°C. The result was a cylinder of uranium metal and MgF2 slag. The crossed cut uranium cylinder showed a smooth and homogeneous surface without inclusions of slag, pores or blisters. The yield of the reaction was of the order of 75% with respect to the expected theoretical value. The uranium cone obtained fulfilled the required conditions for source material for nuclear fuel fabrication, with a uranium content of 97.5%.

A Solution for Municipal Solid Waste Treatment

This article describes MSW(Municipal Solid Waste)management with APG(Arc Plasma Gasification)technology.First,a brief description of the process and reactor configurations is presented,listing some advantages and disadvantages.Then,alternatives for producing electrical energy with the residue of synthesis gas are addressed.Finally,this technology is proposed as an alternative to face the significant problem of eliminating MSW on a large scale.

Construction of a Potentiostat to Perform Electrochemical Impedance Spectroscopy (EIS) Tests

In this work, it was developed the construction of a potentiostat for the execution of Electrochemical Impedance Spectroscopy (EIS) experiments, using an Agilent 33220a signal generator, a RIGOL 1064b oscilloscope and a protoboard for the connection of operational amplifiers to an electrochemical cell. The coordination of the global operation, in addition to data acquisition, was performed using a code generated in the LabVIEW program. The system analyzed was the corrosion of an 1100 aluminum plate in water, in order to compare the results obtained by other authors. The data acquisition consisted in obtaining the values of amplitude, RMS voltage and phase angle between the generated power signals and the current output, in order to obtain the impedance of the system, for different signal frequencies. Finally, the values obtained were plotted on a Nyquist diagram. In this way, the objective of this article is to demonstrate that with conventional laboratory equipment it is possible to implement an experimental device, capable of delivering results similar to those obtained by commercial equipment.