Furthermore, control tests were performed to demonstrate the effect of A. ferrooxidans in uranium bioleaching process and showed that the addition of this . PDF | This review describes the involvement of different microorganisms for the recovery of uranium from the ore. Mainly Acidithiobacillus forrooxidans. initial work on uranium bioleaching in the early s was taken to prevent oxidation rate of iron that may affect uranium’s microbial leaching.
|Country:||Antigua & Barbuda|
|Published (Last):||6 July 2018|
|PDF File Size:||13.23 Mb|
|ePub File Size:||4.78 Mb|
|Price:||Free* [*Free Regsitration Required]|
In the acidification period, there occurs a uranium concentration peak. However, these are expensive reagents, and they create environmental uraniuum by releasing harmful impurities into the leaching circuit.
In this type of ore, many minerals such as pyrite and urinate belong to reduced substances. Uranium mineralizations are product in low level structure of tectonic fault, which mainly contain pitchblende, coffinite, fluorite silicate uranium, lead, and zinc.
A study of the bioleaching of a Spanish uranium ore. Vogel AI In: The redox potential of PLS is much lower than that of bacteria culture. In practice, the iron is usually obtained from pyrite — which is either associated with or added to the ore, and a high redox potential is achieved by adding oxidising agents such as pyrolusite MnO 2 and sodium chlorate NaClO 3.
Continued Multicolumns Bioleaching for Low Grade Uranium Ore at a Certain Uranium Deposit
A study of the bioleaching of spanish uranium ore. Leaching in columns simulates percolation leaching because the conditions are very biolfaching to those in the heap [ 5 ]. Fluoride element analysis of the sample by potassium hydroxide digestion and measurement by fluoride electrode indicated that fluoride weight is high 1. In most cases, uranium on the Witwatersrand occurs as uraninite, which requires an oxidative leach for its extraction. When the pH value of irrigating solution reaches over 2.
Journal of Nanomaterials
This indicates that during this stage most easily consumptive acid minerals such as calcite of this ore are almost reacted by acid uarnium the large fractures. The uranium recovery is highly leached The bacterial strain that was used in the leaching experiments was isolated from the Jaduguda mine water sample.
Bioleaching has lots of advantages compared with traditional heap leaching. Biolexching, the uranium concentration of pregnant leaching solution PLS is low. The compositions of the nutrient growth medium are from PLS at this deposit. In this paper, one of the biggest granite uranium deposits located in south China with high fluoride mineral is selected for study.
In this type of system, one purpose is the increasing redox potentials of this system; the other purpose is that the iron oxidizing bacteria can grow in the column. It has been established that this ratio must be greater than 4 and not in excess of 20 in order to avoid any effects of the wall [ 910 ].
That is, bacteria activity was enhanced after they underwent the former column. Iron oxidizing bacteria are a good worker who can do this job. The result demonstrates that the highest leaching of base metals is achieved at low pH values under high redox conditions where ferric iron remains in solutions [ 16 ].
Articles from Indian Journal of Microbiology are provided here courtesy of Springer. So we try to use continued multicolumns bioleaching in uranium to model multiheaps bioleaching as to improve the production efficiency and reduce the production cost. Those tiny fractures around ot minerals will be enlarged as well. However, the fluoride content 1.
During bioleaching period, redox potentials increase and uranium concentrations are also increased as shown in Figures 5 and 6. The speed of pump is changed in the test to control ursnium time and intensity. Irrigation method is that one day we use bacteria as irrigation solution after domestication by air uraniu, 24 hours for increasing the activity of bacteria and also increasing the redox potential, and the next day we use PLS from the former column which contains ferrous iron as the nutrition for those iron oxidizing bacteria in order to help the bacteria grow in the ore.
There was a problem providing the content you requested
The uranium minerals will be wrapped up by them. Under these circumstances, the precipitation of both goethite and jarosite-type basic compounds will not occur in the next bioleaching stage and the bacterium will grow in the column as bacteria are adapted to this pH and the culture from the irrigating solution PLS of pH bioleacning. When pH is lower than 1. This indicates that the bacteria grow well in these columns. Uranium recovery for each column during the leaching.
A solid sample of uranium ore from the normal production of ore in this deposit plant was used. This work biolleaching financially supported by National Plans Grant no.
Back-scattered electron image bioleachiny EPMA before leaching. The sulfur weight is 0. Obviously, the average uranium concentration of PLS of later column is higher than that of the former one.
Uranium Bioleaching – MINTEK | MINTEK
In the next 20 days, acid consumption increases still fast but it is lower than that in the first 10 days. During this experiment, both redox potentials of irrigating solution and PLS boleaching measured in each day. Table 1 shows the chemical and mineralogical composition of the sample.
The test process and the specific implementation process are as follows: Subscribe to Table of Contents Alerts.