ISL and processing
While ISL mining, water is pumped to the surface of production wells that contain uranium at very low concentrations, the order of parts per million concentrations. The next step in the process of ISL is to extract the uranium-dicarbonate. The extraction takes place through the exchange of ions in a chemical processing plant. "The ion exchange process is very similar to a home Culligan ® water softeners," says Anthony. "It removes the hardness orCalcium from the water, filling it with soda, with ion exchange resins. If you go to Lowes or Home Depot and buy a water softener, you have basically a home version of a uranium extraction plant. "The main difference is having your water softener is a cation exchanger." For a uranium plant properly, you need to clarify an anion exchange resin, which was designed to use uranium exposure, "Anthony.
And what this magical "ion exchange resin" is? The resin isconsisting of small polymer beads, the particles are charged anions with an affinity for uranium. "There are literally millions of these tiny resin beads in a jar, can absorb the low concentration of uranium in solution," said Anthony. Adsorption is when something else attracted by something or clinging to them, like static electricity.
Why should the uranium, because this process? "In essence, the ion exchange process is a treatment (reduction) process, focusesconcentrate large amounts of low-grade uranium solution in a volume much smaller with a much higher concentration of uranium, "said Anthony. In other words, the treatment is only the concentration of uranium from large amounts of water they are in a compact reduced form. The preferred method is to ion exchange.
Anthony gave an example from the practice of the treatment process: "Three million gallons of diluted solution Wellfield concentrations of uranium, the100 parts per million less than 0.10 grams / liter, is passed through a bed of ion exchange resin. This could rise to 24 hours when the solution flows to 2,500 gallons per minute. After this period, the resin is loaded with about 2,500 pounds of uranium. "
Stripping of uranium
Stripping of uranium, the process is called elution. This is done through chemical exchange of positive and negative ions. Resins are ranked by the charge on theactive centers. "The active sites on the resin for positive and negatively charged anion to cation resins," Norris enlightens us. "The resin is capable of extracting ions from a chemical solution, which is an active site is derived," he continued. "In our case, the chloride ions from the salt obtained by the usual narrative temporarily stabilize or neutralize the positively charged active site." The negatively charged chloride ion attaches to the side of positive charge,held in place, which Norris called "electrostatic forces." If negatively charged ions such as uranyl dicarbonate are brought into contact with the solution, which will kick off the Chloride and replace it with the uranyl dicarbonate.
That was the lesson of chemistry. Anthony took in a few words "is enough to move. There is a higher affinity for chloride ions on the resin for uranium. Thus, the uranium is removed from the resin bed." TreatmentSystem chemically strip the uranium from the resin loaded by immersing the whole package of uranium-loaded resin solution in a salt bath. "The volume of saline solution is of the order of 10,000 gallons, which leads to a solution concentration of 30 g / l of uranium," said Anthony, describes the process by which uranium is concentrated. "The concentration of uranium stripped solution 300 times more than the solution Wellfield has increased," he informed. "The concentration is nowbe cost for recycling: rainfall, drainage, drying and drums for a nuclear power plant. "
FIRST URANIUM in the drum
After uranium has been removed from the solution, it's like. At this point in the pipeline, you have yellowcake slurry. Up close, it seems a sort of yellow and wet cement mixture runny. Drainage is exactly removes water from the mixture of yellowcake.
"I use a filter press, a devicethat is designed to separate solids from solutions, "said Anthony. filter presses are widely used in various types of food processing, chemicals and drugs all over the world." The solid uranium, now more as yellowcake, are stored in the filter press, where they can be washed and then air-dried, before drying to a powder with a vacuum dryer at low temperature, "said Anthony us step by step through this process.
So what is the filter press and how it endswith the yellowcake over, when you're done? "It 'a series of plates and hollow structure, or it could be a series of rooms built," said Anthony. "Filter cloth draped over the tables in the rooms of plaster or depth. The yellowcake slurry is through the filter allows the passage of the liquid phase through the fabric filter, with the uranium oxide is pumped into the device." Antonio wants to maintain the degree of filter press with the yellowcake there. "And 'then washed withsoap and water to move chloride ions at a low level, "said Anthony. If you do not remove chloride concentrations permitted height of a uranium enrichment plant is required is a penalty assessed against extradition.
The final steps of transmitting the yellowcake dryer empty. The uranium oxide, the color depends on how high or low temperatures is used to dry the "yellow cake". Patrick Drummond, the Smith-Highland Ranch facility superintendent, showed us pure uraniumoxide dried at high temperatures. It was almost black. After drying is completed, the approval of DOE uranium is 55 liters barrels packed and transported to an enrichment plant. And 'when the enriched uranium can ultimately lead to supply a nuclear reactor and provide a cheap source of energy for energy production.
Copyright © 2007 by Interview magazine, Inc. ALL RIGHTS RESERVED.
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