SU910815A1 - Process for leaching ores and concentrates using microorganisms - Google Patents

Description

(54) METHOD OF LEASTING OF ORES AND CONCENTRATES USING MICROORGANISMS

one

This invention relates to a hyaromete number Surgeon, in particular to leaching of ores and concentrates using micro-organisms, i.e., a bacterial leach.

There are known methods for leaching ores and concentrates with the use of micro-, organisms, which are carried out in several stages: contacting the ore or concentrate with a nutrient medium containing microorganisms Ttiiobc C1 E and erroxi 3as, separation of residues. leaching from pacTBopaCll, separating metals from solution and returning the solution to the process 23.

However, these methods do not envisage the reuse of the most active bacterial cells from circulating solutions adapted to the targeting conditions and elevated concentrations of heavy metal ions in the solution. Active microorganism cells: either they are lost completely in the case of an open leaching scheme, or more than 1-1. some of them die at the stage of isolation of metals and metals from solutions after leaching. As a result, it is not possible to achieve a high leaching rate of metals and reduce the duration of the process.

The closest to the technical essence of the method is bacterial injection of copper zinc concentrates, including contacting the concentrate with water and nutrient medium containing T-fetfooxidan, thickening of target products, release of iron, zinc, copper and cadmium from clarified solutions, return of growth

15 thieves in the process. The extraction of metals is carried out with a change in the pH of the solution from 1.5 times the carburization of copper to 3–3.5 Sch) and the precipitation of iron and to a pH of 6.8-7 with the precipitate of zinc. With these

20 operashuh additionally add lime Z to the solution.

Claims (3)

However, during the operations of sowing iron, zinc, copper, and cadmium of & 391, fine precipitates develop. rye cause coexistence of significant portions of cells. As a result, cell concentration Qi drops from 1O to lO -lO in 1 ml, that is, 1OOOO-100OOOO times, and the remaining cells are inactive and require additional activation when nutrient salts are added and the solution is aerated for 8-24 hours. HecMoow p on this, the activity of baitary ostaers is lower than that of the production cooler. Thus, a solution containing low concentrations of bacterial cells enters the circulation. Since the generation time of T.evrooxidahS cells is 8-12 hours, by the end of the process, which has a duration of 80-120 hours, it does not work to get cell concentrations above 1O per 1 ml. This, in turn, is a factor limiting the maximum leaching rate. The aim of the invention is to increase the leaching rate without reducing the completeness of extraction of valuable components into the solution by increasing the concentration of microorganisms in the leaching solutions and maintaining their activity. The goal is achieved by those. that according to the method of leaching ores and concentrates using microorganisms, including contacting the ore or concentrate with water and a nutrient medium containing microorganisms, separating the leaching residues from the solution containing metal ions and microorganisms, separating metals from the solution, returning the solution to circulation, before separating the metals microorganisms are concentrated from the leaching solution, after h & He separates the resulting biomass in the paste from the solution and returns it to the process. Concentration of biomass is carried out by centrifugation. Thus, the isolation of bacterial cells before the plumage of the precursors of the meta-particles taken immediately after leaching prevents their loss with metal deposits and retains the activity inherent in the production culture. The centrifuging operations will increase the cell number per unit volume of the leach solution by a factor of 10 and increase the leaching rate by 15% without reducing the stacks of metal extraction into the solution. Bacterial implantation of zinc ve copper-zinc concentrate is carried out according to a scheme including bacterial leaching of concentrate in packs with a volume of 160 l each at pH 2-2.2, dehydration of residual iron, precipitation of iron with lime to pH 3.1, cementation of copper and cadmium zinc dust at pH 1.8, precipitation of zinc soda to pH 6.8, regeneration of solutions by adding iron (II) sulfate, sulfuric acid to pH 2, and aeration with air. Bacterial leaching is also carried out according to a scheme using centrifuging bacterial cells prior to metal operations. The resulting biomass of cells in the form of a paste is increased into the process. The regeneration of the bacteria is not carried out. The extraction of metals from solution is carried out according to the same scheme as in the experiment without the centrifuging of microbes. The original culture of microorganisms in both experiments hiobaciEEus fev i ooxidans. VpTselachi. copper-zinc concentrate of croup “80 microns contains,%: q 13.5, copper 6.24, iron 28.48, sulfur 38.31 and cadmium 0.049. In the experiment without centrifugation, a leaching cake was obtained with a zinc content of 4% with an extraction of 80% in 85 hours. The content was. respectively. The concentration of zinc, cadmium copper in solution is on average 20.87; QQ O, O2 g / l, respectively. In the experiment on the proposed technology with the center of T. ev rooxidci cells, the zinc content of 4% in the cake was reached in 73 hours. The concentration of valuable components in the solution and in the residues of excess and treatment remained at the same level as the known technology. Thus, without reducing the completeness of the extraction, which is 80% for zinc, an increase in the target rate by 15% is obtained. An increase in the leaching rate is accompanied by an increase in the concentration of bacteria, which in the experiment with centrifuging 10 0, 5-10 cells / ml compared with 10 cells / ml without centrifugation. An increase in leaching rate of 15% implies a reduction in economic costs for processing 1 ton of concentrate by an average of 12-15% in terms of reducing the amount of construction and operating costs. Claim 1. Method of optics and concentrates using microorganisms MOB, including contacting the ore or concentrate with boil and nutrient medium containing microorganisms, recovery of leaching residue containing metal ions and microorganisms, separation of metal ions from solution, recovery of solution per revolution, characterized in that in order to increase the leaching rate, the concentration of microorganisms is carried out by the release of metals from the solution, and then the separation The resulting biomass from the solution is returned to the process. 2. A method according to claim 1, in which it is possible that the termination of the microorganisms is carried out with uetrrpmtiynqx vanilla. Sources of information taken into account during the examination 1. US patent N9 ZZO5353, cl. 75-101, published in 1969. 2. Canadian patent number 960463, cl. 53-18, published. 1975. 3. To produce universities Tsvetna metallurgists, 1979, No. 3, p. 5-12.