Business plan for tungsten ore beneficiation. Maintaining the main method of beneficiation of tungsten ores and the use of auxiliary dehydration processes in the technological scheme of approx. Calculation of crushing scheme with equipment selection
Main enrichment
For some beneficiation factories, in pre-beneficiation, first Xinhai will use moving screen jigger, and then enter into finishing operations.
Gravity enrichment
For wolframite gravity technology, Xinhai usually uses a gravity process that includes multi-stage jigging, multi-stage table and middling product regrinding. That is, after fine crushing, worthy ores, which, through the classification of a vibrating screen, carry out multi-stage jigging and produce coarse sand from jigging and gravity. Then the ballast products of the large class jigging will enter the mill for additional grinding. And the ballast products of the small class jigging will enter sorting through the classifications multi-stage table, then coarse sand is produced from gravity and from the table, then the tailings from the table will enter the tailings hopper, the middlings from the table are then returned to the regrinding cycle stage, and the gravity coarse sand from the jig and the table enters the finishing operation.
Cleaning
In the wolframite finishing operation, a combined flotation and gravity enrichment technology or a combined flotation technology - gravity and magnetic enrichment is usually used. At the same time, returns the accompanying item.
The finishing operation usually uses a combined method of flotation and enrichment table and washing of sulfur pyrites through flotation. At the same time, we can enter into the flotation separation of sulfur pyrites. After this, wolframite concentrates are produced, if wolframite concentrates contain scheelite and cassiterite, then wolframite concentrates, scheelite concentrates and cassiterite concentrates are produced through a combined flotation and gravity enrichment technology or a combined gravitational and magnetic flotation technology enrichment.
Fine sludge treatment
The processing method for fine sludge in Xinhai usually goes like this: firstly, desulphurization is carried out, then, according to the properties of the fine sludge and material, gravity, flotation, magnetic and electrical enrichment technology is used, or a combined enrichment technology of several technologies is used to make the return tungsten ore, and At that time, associated ore minerals will be disposed of.
Practical examples
The Xinhai wolframite object was taken as an example; the size distribution of the ore of this mine was inhomogeneous, and the ore was very heavily sludged. The initial technological scheme used by the enrichment plant, which includes pre-enrichment crushing, gravity and re-cleaning, resulted in huge losses due to a number of technological defects tungsten ores ov small class, high cost of enrichment, such as the poor state of comprehensive enrichment indicators. In order to improve the wolframite sorting status, this beneficiation plant authorized Xinhai to carry out technical reconstruction tasks. After careful research on the properties of ore and beneficiation technology of this factory, Xinhai optimized the technology for beneficiation of wolframite of this factory and added fine sludge processing technology. and ultimately obtain ideal enrichment rates. The enrichment indicator of the factory before and after the transformation is as follows:
After the transformation, the extraction of tungsten ore increased significantly. And mitigated the effects of fine sludge on the wolframite sorting process, achieved good recovery rate, effectively improved the economic efficiency of the factory.
Introduction
1 . The importance of technogenic mineral raw materials
1.1. Mineral resources of the ore industry in the Russian Federation and the tungsten sub-industry
1.2. Technogenic mineral formations. Classification. Need for use
1.3. Technogenic mineral formation Dzhidinsky VMC
1.4. Goals and objectives of the study. Research methods. Provisions for defense
2. Study of the material composition and technological properties of stale tailings from the Dzhidinsky MMC
2.1. Geological testing and evaluation of tungsten distribution
2.2. Material composition of mineral raw materials
2.3. Technological properties of mineral raw materials
2.3.1. Grading
2.3.2. Study of the possibility of radiometric separation of mineral raw materials in the original size
2.3.3. Gravity analysis
2.3.4. Magnetic analysis
3. Development of a technological scheme
3.1. Technological testing of various gravity devices for the enrichment of stale tailings of various sizes
3.2. Optimization of the general waste processing scheme
3.3. Pilot testing of the developed technological scheme for the enrichment of general waste and an industrial plant
Introduction to the work
The sciences of mineral processing are, first of all, aimed at developing the theoretical foundations of mineral separation processes and the creation of processing apparatus, at revealing the relationship between the distribution patterns of components and separation conditions in processing products in order to increase the selectivity and speed of separation, its efficiency and economy, and environmental safety.
Despite significant mineral reserves and a decline in last years resource consumption, depletion mineral resources is one of the most important problems in Russia. Poor use of resource-saving technologies contributes to large losses of minerals during the extraction and enrichment of raw materials.
An analysis of the development of equipment and technology for mineral processing over the past 10-15 years indicates significant achievements of domestic fundamental science in the field of knowledge of the basic phenomena and patterns in the separation of mineral complexes, which makes it possible to create highly efficient processes and technologies for the primary processing of ores of complex composition and, as Consequently, to provide the metallurgical industry with the necessary range and quality of concentrates. At the same time, in our country, in comparison with developed foreign countries, there is still a significant lag in the development of the machine-building base for the production of main and auxiliary enrichment equipment, in its quality, metal intensity, energy intensity and wear resistance.
In addition, due to the departmental affiliation of mining and processing enterprises, complex raw materials were processed only taking into account the necessary industry needs for a specific metal, which led to the irrational use of natural mineral resources and increased costs for waste storage. Currently accumulated
more than 12 billion tons of waste, the content of valuable components in which in some cases exceeds their content in natural deposits.
In addition to the above negative trends, since the 90s, the environmental situation at mining and processing enterprises has sharply worsened (in a number of regions, threatening the existence of not only biota, but also humans), there has been a progressive decline in the production of non-ferrous and ferrous metal ores, mining and chemical raw materials, deterioration in the quality of processed ores and, as a consequence, the involvement in the processing of difficult-to-process ores of complex material composition, characterized by a low content of valuable components, fine dissemination and similar technological properties of minerals. Thus, over the past 20 years, the content of non-ferrous metals in ores has decreased by 1.3-1.5 times, iron by 1.25 times, gold by 1.2 times, the share of difficult ores and coal has increased from 15% to 40% of the total mass of raw materials supplied for enrichment.
Human impact on natural environment in the process of economic activity now acquires global character. In terms of the scale of extracted and transported rocks, transformation of the relief, impact on the redistribution and dynamics of surface and groundwater, activation of geochemical transfer, etc. this activity is comparable to geological processes.
The unprecedented scale of extracted mineral resources leads to their rapid depletion, the accumulation of large amounts of waste on the Earth’s surface, in the atmosphere and hydrosphere, the gradual degradation of natural landscapes, a reduction in biodiversity, and a decrease in the natural potential of territories and their life-supporting functions.
Ore processing waste storage facilities are objects of increased environmental hazard because of them negative impact to the air basin, underground and surface water, soil cover over vast areas. Along with this, tailings dumps are little-studied technogenic deposits, the use of which will make it possible to obtain additional
sources of ore and mineral raw materials with a significant reduction in the scale of disturbance of the geological environment in the region.
Production of products from technogenic deposits, as a rule, is several times cheaper than from raw materials specially mined for this purpose, and is characterized by a quick return on investment. However, the complex chemical, mineralogical and granulometric composition of tailings, as well as a wide range of minerals contained in them (from main and associated components to the simplest building materials) make it difficult to calculate the total economic effect of their processing and determine individual approach to the assessment of each tailings dump.
Consequently, at the moment a number of insoluble contradictions have emerged between the change in the nature of the mineral resource base, i.e. the need to involve difficult-to-process ores and technogenic deposits in the processing, the environmentally aggravated situation in mining regions and the state of technology, technology and organization of primary processing of mineral raw materials.
The issues of using waste from the enrichment of polymetallic, gold-containing and rare metals have both economic and environmental aspects.
In achieving the current level of development of the theory and practice of processing tailings from the enrichment of non-ferrous, rare and precious metal ores, V.A. made a great contribution. Chanturia, V.Z. Kozin, V.M. Avdokhin, SB. Leonov, L.A. Barsky, A.A. Abramov, V.I. Karmazin, SI. Mitrofanov and others.
An important component of the overall strategy of the ore industry, incl. tungsten, is the increased use of ore processing waste as additional sources of ore and mineral raw materials, with a significant reduction in the scale of disturbance of the geological environment in the region and the negative impact on all components environment.
In the field of using ore processing waste, the most important thing is a detailed mineralogical and technological study of each specific
an individual technogenic deposit, the results of which will allow the development of an effective and environmentally friendly technology for the industrial development of an additional source of ore and mineral raw materials.
The problems considered in the dissertation work were solved in accordance with the scientific direction of the Department of Mineral Processing and Engineering Ecology of the Irkutsk State Technical University on the topic “Fundamental and technological research in the field of processing of mineral and technogenic raw materials for the purpose of their integrated use, taking into account environmental problems in complex industrial systems" and paper topic No. 118 "Study of the beneficiation of stale tailings of the Dzhida VMC."
Goal of the work- scientifically substantiate, develop and test
rational technological methods for enriching stale
The following tasks were solved in the work:
Evaluate the distribution of tungsten throughout the entire space of the main
technogenic education of the Dzhida VMC;
study the material composition of the stale tailings of the Dzhizhinsky VMC;
study the contrast of stale tailings in the original size in terms of the content of W and S (II);
to study the gravitational enrichment of stale tailings of the Dzhida VMC in various sizes;
determine the feasibility of using magnetic enrichment to improve the quality of crude tungsten-containing concentrates;
to optimize the technological scheme for the enrichment of technogenic raw materials of the general waste treatment plant of the Dzhida VMC;
conduct pilot tests of the developed scheme for extracting W from the stale tailings of DVMC;
Develop a circuit diagram of devices for industrial processing stale tailings from the Dzhida VMC.
To carry out the research, a representative technological sample of stale tailings from the Dzhida VMC was used.
When solving the formulated problems, the following were used research methods: spectral, optical, chemical, mineralogical, phase, gravitational and magnetic methods for analyzing the material composition and technological properties of initial mineral raw materials and enrichment products.
The following are submitted for defense: basic scientific principles:
The patterns of distribution of initial technogenic mineral raw materials and tungsten by size classes have been established. The need for primary (preliminary) classification by size of 3 mm has been proven.
Installed quantitative characteristics stale tailings of ore processing of ores from the Dzhida VMC in terms of WO3 and sulfide sulfur content. It has been proven that the initial mineral raw materials belong to the category of non-contrasting ores. A reliable and reliable correlation between the contents of WO3 and S (II) was revealed.
Quantitative patterns of gravitational enrichment of stale tailings from the Dzhida VMC have been established. It has been proven that for source material of any size, an effective method for extracting W is gravitational enrichment. Forecast technological indicators of gravitational enrichment of initial mineral raw materials have been determined V of various sizes.
Quantitative patterns of distribution of stale ore dressing tailings of the Dzhida VMC into fractions of different specific magnetic susceptibility have been established. The effectiveness of the sequential use of magnetic and centrifugal separation has been proven to improve the quality of rough W-containing products. The technological modes of magnetic separation have been optimized.
Material composition of mineral raw materials
When examining a secondary tailings dump (emergency discharge tailings dump (EDT)), 35 furrow samples were taken from pits and clearings along the slopes of the dumps; the total length of the furrows is 46 m. The pits and clearings are located in 6 exploration lines, spaced 40-100 m from each other; the distance between pits (clearings) in exploration lines is from 30-40 to 100-150 m. All lithological varieties of sands were tested. Samples were analyzed for W03 and S(II) content. In this area, 13 samples were taken from pits with a depth of 1.0 m. The distance between the lines is about 200 m, between the workings - from 40 to 100 m (depending on the distribution of the same type of lithological layer). The results of sample analyzes for WO3 and sulfur content are given in table. 2.1. Table 2.1 - Content of WO3 and sulfide sulfur in private samples of CAS It can be seen that the content of WO3 ranges from 0.05-0.09%, with the exception of sample M-16, selected from medium-grained gray sands. In the same sample, high concentrations of S (II) were found - 4.23% and 3.67%. For individual samples (M-8, M-18), a high content of S sulfate was noted (20-30% of the total sulfur content). In the upper part of the emergency discharge tailings dump, 11 samples of various lithological varieties were taken. The content of WO3 and S (II), depending on the origin of the sands, varies over a wide range: from 0.09 to 0.29% and from 0.78 to 5.8%, respectively. Elevated WO3 contents are typical for medium-to-coarse-grained sand varieties. The S(VI) content is 80 - 82% of the total S content, but in individual samples, predominantly with low contents of tungsten trioxide and total sulfur, it decreases to 30%.
The deposit's reserves can be assessed as Pj category resources (see Table 2.2). Along the upper part, the length of the pit varies in a wide range: from 0.7 to 9.0 m, therefore the average content of controlled components is calculated taking into account the parameters of the pits. In our opinion, based on the given characteristics, taking into account the composition of stale tailings, their preservation, conditions of occurrence, contamination household waste, their WO3 content and the degree of sulfur oxidation, can only be of industrial interest top part emergency discharge tailings with resources of 1.0 million tons of sand and 1330 tons of WO3 with a WO3 content of 0.126%. Their location in close proximity to the projected processing plant(250-300 m) favors their transportation. The lower part of the emergency discharge tailings dump is subject to disposal as part of the environmental rehabilitation program for the city of Zakamensk.
5 samples were taken from the deposit area. The interval between sampling points is 1000-1250 m. Samples were taken over the entire thickness of the layer and analyzed for the content of WO3, Btot and S (II) (see Table 2.3). Table 2.3 - Content of WO3 and sulfur in private ATO samples From the analysis results it is clear that the content of WO3 is low, varying from 0.04 to 0.10%. The average S(II) content is 0.12% and is of no practical interest. The work carried out does not allow us to consider the by-product alluvial tailings dump as a potential industrial facility. However, as a source of environmental pollution, these formations must be disposed of. The main tailings dump (MTD) was explored along parallel exploration lines oriented at azimuth 120 and located 160 - 180 m from each other. The exploration lines are oriented across the strike of the dam and the slurry pipeline, through which the ore tailings were discharged, deposited subparallel to the dam crest. Thus, the exploration lines were also oriented across the bedding of technogenic deposits. Along the exploration lines, a bulldozer drove trenches to a depth of 3-5 m, from which pits were drilled to a depth of 1 to 4 m. The depth of the trenches and pits was limited by the stability of the walls of the workings. The pits in the trenches were made through 20 - 50 m in the central part of the deposit and through 100 m - on the south-eastern flank, on the area of the former settling pond (now dried up), from which water was supplied to the processing plants during the operation of the plant.
The area of the OTO along the distribution boundary is 1015 thousand m (101.5 hectares); along the long axis (along the valley of the Barun-Naryn river) it extends for 1580 m, in the transverse direction (near the dam) its width is 1050 m. In this area, 78 pits were made from pre-created trenches in five main exploration lines. Consequently, one pit illuminates an area of 12,850 m, which is equivalent to an average network of 130x100 m. In the central part of the field, represented by sands of different grains, in the area where slurry lines are located on an area of 530 thousand m (52% of the TMO area), 58 pits and one well (75% all workings); The exploration network area averaged 90x100 m2. On the extreme south-eastern flank, on the site of a former settling pond in the area of development of fine-grained sediments - silts, 12 pits (15% of the total number) were drilled, characterizing an area of about 370 thousand m (37% of the total area of the technogenic deposit); the average network area here was 310x100 m2. In the area of transition from heterogeneous sands to silts, composed of silty sands, on an area of about 115 thousand m (11% of the area of the technogenic deposit), 8 pits were drilled (10% of the number of workings in the technogenic deposit) and the average area of the exploration network was 145x100 m. The average length the sampled section at the technogenic deposit is 4.3 m, including for different-grained sands - 5.2 m, silty sands - 2.1 m, silts - 1.3 m. Absolute marks The modern topography of the surface of the technogenic deposit in the tested sections varies from 1110-1115 m near the upper part of the dam, to 1146-148 m in the central part and 1130-1135 m on the southeastern flank. In total, 60 - 65% of the capacity of the technogenic deposit has been tested. Trenches, pits, strippings and burials were documented in M 1:50 -1:100 and tested with a furrow with a cross section of 0.1x0.05 m2 (1999) and 0.05x0.05 m2 (2000). The length of the furrow samples was 1 m, the weight was 10 - 12 kg in 1999. and 4 - 6 kg in 2000. The total length of the tested intervals in the exploration lines was 338 m, in general, taking into account the areas of detailing and individual sections outside the network - 459 m. The weight of the samples taken was 5 tons.
The samples, together with a passport (characteristics of the rock, sample number, production and performer) were packaged in plastic and then fabric bags and sent to the RAC of the Republic of Buryatia, where they were weighed, dried, analyzed for the content of W03, and S (II) according to NS AM methods. The accuracy of the analyzes is confirmed by the comparability of the results of ordinary, group (RAC analyses) and technological (TsNIGRI and VIMS analyses) samples. The results of the analysis of private technological samples taken at the OTO are given in Appendix 1. The main (OTO) and two secondary tailings dumps (KhAT and ATO) of the Dzhida VMC were statistically compared in terms of WO3 content using the Student's t test (see Appendix 2). With a confidence probability of 95% it was established: - no significant statistical difference in WO3 content between private samples of side tailings; - average results of OTO testing for WO3 content in 1999 and 2000. belong to the same general population. Consequently, the chemical composition of the main tailings pond changes insignificantly over time under the influence external influences. All general waste reserves can be processed using a single technology.; - average sampling results of the main and side tailings dumps in terms of WO3 content differ significantly from each other. Consequently, to involve mineral raw materials from side tailings, the development of local enrichment technology is required.
Technological properties of mineral raw materials
Based on their granular composition, sediments are divided into three types of sediments: heterogeneous sands; silty sands (silty); silts There are gradual transitions between these types of sediments. Clearer boundaries are observed in the thickness of the section. They are caused by the alternation of sediments of different grain compositions, different color(from dark green to light yellow and gray) and different material composition (quartz-feldspathic nonmetallic part and sulfide with magnetite, hematite, hydroxides of iron and manganese). The entire thickness is layered - from fine to coarsely layered; the latter is more typical for coarse-grained varieties of sediments or layers of significant sulfide mineralization. Fine-grained (silty, silt fractions, or layers composed of dark-colored materials - amphibole, hematite, goethite) usually form thin (a few cm - mm) layers. The occurrence of the entire thickness of sediments is subhorizontal with a predominant fall of 1-5 in the northern directions. Sands of different grains are located in the northwestern and central parts of the OTO, which is due to their sedimentation near the source of discharge - the pulp pipeline. The width of the strip of different-grained sands is 400-500 m; along the strike they occupy the entire width of the valley - 900-1000 m. The color of the sands is gray-yellow, yellow-green. The granular composition is variable - from fine-grained to coarse-grained varieties up to lenses of gravelstones 5-20 cm thick and up to 10-15 m long. Silty (silty) sands stand out in the form of a layer 7-10 m thick (horizontal thickness, outcrop 110-120 m ). They lie under heterogeneous sands. In cross-section they represent a layered formation of gray, greenish-gray color with alternation of fine-grained sands with layers of silt. The volume of silts in the section of silty sands increases in the southeast direction, where silts make up the main part of the section.
Silts make up the southeastern part of the OTO and are represented by finer particles of enrichment waste of dark gray, dark green, bluish-green color with layers of grayish-yellow sand. The main feature of their structure is a more uniform, more massive texture with less frequent and less clearly defined layering. The silts are underlain by silty sands and lie on the base of the bed - alluvial-deluvial deposits. The granulometric characteristics of OTO mineral raw materials with the distribution of gold, tungsten, lead, zinc, copper, fluorite (calcium and fluorine) by size class are given in Table. 2.8. According to granulometric analysis, the bulk of the OTO sample material (about 58%) has a particle size of -1 + 0.25 mm, 17% each is coarse (-3 + 1 mm) and small (-0.25 + 0.1) mm classes. The share of material with a particle size of less than 0.1 mm is about 8%, of which half (4.13%) is of the slurry class - 0.044 + 0 mm. Tungsten is characterized by a slight fluctuation in content in size classes from -3 +1 mm to -0.25+0.1 mm (0.04-0.05%) and a sharp increase (up to 0.38%) in size class -0 .1+0.044 mm. In the slurry class -0.044+0 mm, the tungsten content is reduced to 0.19%. The accumulation of hübnerite occurs only in small-sized material, that is, in the class -0.1 + 0.044 mm. Thus, 25.28% of tungsten is concentrated in the -0.1+0.044 mm class with an output of this class of about 4% and 37.58% in the -0.1+0 mm class with an output of this class of 8.37%. Differential and integral histograms of the distribution of particles of GTO mineral raw materials by size class and histograms of the absolute and relative distribution of W by size class of GTO mineral raw materials are presented in Fig. 2.2. and 2.3. In table Table 2.9 shows data on the dissemination of hübnerite and scheelite in the OTO mineral raw material of the original size and crushed to - 0.5 mm.
In the -5+3 mm class of initial mineral raw materials there are no pobnerite and scheelite grains, as well as intergrowths. In the -3+1 mm class, the content of free scheelite and hübnerite grains is quite large (37.2% and 36.1%, respectively). In the -1+0.5 mm class, both mineral forms of tungsten are present in almost equal quantities, both in the form of free grains and in the form of intergrowths. In thin classes -0.5+0.25, -0.25+0.125, -0.125+0.063, -0.063+0 mm, the content of free grains of scheelite and hübnerite is significantly higher than the content of intergrowths (the content of intergrowths varies from 11.9 to 3. 0%) The size class -1+0.5 mm is limiting and in it the content of free grains of scheelite and hübnerite and their intergrowths is almost the same. Based on the data in table. 2.9, we can conclude that it is necessary to classify delimed mineral raw materials OTO according to a particle size of 0.1 mm and separate enrichment of the resulting classes. From the large class, it is necessary to separate the free grains into a concentrate, and the tailings containing splices must be subjected to further grinding. The crushed and deslimed tailings should be combined with the deslimed class -0.1+0.044 of the initial mineral raw materials and sent to gravity operation II in order to extract fine grains of scheelite and pobnerite into the middling product.
2.3.2 Study of the possibility of radiometric separation of mineral raw materials in the original size Radiometric separation is the process of large-piece separation of ores according to the content of valuable components, based on selective influence various types radiation on the properties of minerals and chemical elements. Over twenty methods of radiometric enrichment are known; the most promising of them are X-ray radiometric, X-ray luminescence, radio resonance, photometric, autoradiometric and neutron absorption. Using radiometric methods, the following technological problems are solved: preliminary enrichment with the removal of waste rock from ore; selection of technological varieties, varieties with subsequent enrichment according to separate schemes; selection of products suitable for chemical and metallurgical processing. The assessment of radiometric enrichment includes two stages: studying the properties of ores and experimental determination of technological indicators of enrichment. At the first stage, the following basic properties are studied: the content of valuable and harmful components, particle size distribution, single- and multi-component contrast of ore. At this stage, the fundamental possibility of using radiometric enrichment is established, the maximum separation indices are determined (at the stage of studying contrast), separation methods and characteristics are selected, their effectiveness is assessed, theoretical separation indices are determined, and a basic diagram of radiometric enrichment is developed, taking into account the features of subsequent processing technology. At the second stage, the modes and practical results of separation are determined, large-scale laboratory tests of the radiometric enrichment scheme are carried out, a rational version of the scheme is selected based on a technical and economic comparison of the combined technology (with radiometric separation at the beginning of the process) with the basic (traditional) technology.
In each specific case, the mass, size and number of technological samples are determined depending on the properties of the ore, the structural features of the deposit and methods of its exploration. The content of valuable components and the uniformity of their distribution in the ore mass are the determining factors in the use of radiometric enrichment. The choice of radiometric enrichment method is influenced by the presence of impurity elements isomorphically associated with useful minerals and in some cases playing the role of indicators, as well as the content of harmful impurities, which can also be used for these purposes.
Optimization of the general waste processing scheme
In connection with the involvement in industrial exploitation of low-grade ores with a tungsten content of 0.3-0.4%, in recent years multi-stage combined enrichment schemes based on a combination of gravity, flotation, magnetic and electrical separation, chemical finishing of low-grade flotation concentrates, etc. have become widespread. . A special International Congress in 1982 from San Francisco. An analysis of the technological schemes of existing enterprises showed that during ore preparation, various methods of preliminary concentration have become widespread: photometric sorting, preliminary jigging, enrichment in heavy environments, wet and dry magnetic separation. In particular, photometric sorting is effectively used at one of the largest suppliers of tungsten products - at the Mount Corbijn plant in Australia, which processes ores with a tungsten content of 0.09% at large factories in China - Taishan and Xihuashan.
For the preliminary concentration of ore components in heavy media, highly efficient Dinavirpul devices from Sala (Sweden) are used. Using this technology, the material is classified and the +0.5 mm class is enriched in a heavy environment represented by a ferrosilicon mixture. Some factories use dry and wet magnetic separation as pre-concentration. Thus, at the Emerson plant in the USA, wet magnetic separation is used to separate the pyrrhotite and magnetite contained in the ore, and at the Uyudag plant in Turkey, class - 10 mm is subjected to dry grinding and magnetic separation in separators with low magnetic intensity to isolate magnetite, and then enriched in high tension separators to separate the garnet. Further enrichment includes table concentration, flotogravity and scheelite flotation. An example of the use of multi-stage combined schemes for the enrichment of low-grade tungsten ores, ensuring the production of high-quality concentrates, are the technological schemes used in Chinese factories. Thus, at the Taishan factory with a capacity of 3000 tons/day of ore, wolframite-scheelite material with a tungsten content of 0.25% is processed. The original ore is subjected to manual and photometric sorting with 55% of waste rock removed to the dump. Further enrichment is carried out on jigging machines and concentration tables. The resulting rough gravity concentrates are finished using flotogravity and flotation methods. Xihuashan, which processes ore with a 10:1 ratio of wolframite to scheelite, uses a similar gravity cycle. The crude gravity concentrate is sent to flotogravity and flotation, through which sulfides are removed. Next, wet magnetic separation of the chamber product is carried out to isolate wolframite and rare earth minerals. The magnetic fraction is sent to electrostatic separation and then flotation of wolframite. The non-magnetic fraction is fed to sulfide flotation, and the flotation tailings are subjected to magnetic separation to produce scheelite and cassiterite-wolframite concentrates. The total WO3 content is 65% with a recovery of 85%.
There has been an increase in the use of the flotation process in combination with chemical finishing of the resulting poor concentrates. In Canada, at the Mount Pleasant plant, flotation technology has been adopted for the beneficiation of complex tungsten-molybdenum ores, including the flotation of sulfides, molybdenite and wolframite. In the main sulfide flotation, copper, molybdenum, lead, and zinc are recovered. The concentrate is cleaned, further crushed, steamed and conditioned with sodium sulfide. The molybdenum concentrate is purified and subjected to acid leaching. Sulfide flotation tailings are treated with sodium fluoride to depress gangue minerals and wolframite is floated with organophosphorus acid, followed by leaching of the resulting wolframite concentrate with sulfuric acid. At the Kantung factory (Canada), the scheelite flotation process is complicated by the presence of talc in the ore, so a primary talc flotation cycle was introduced, then copper minerals and pyrrhotite are floated. The flotation tailings are subjected to gravity enrichment to produce two tungsten concentrates. The gravity tailings are sent to the scheelite flotation cycle, and the resulting flotation concentrate is treated with hydrochloric acid. At the Ixsjöberg factory (Sweden), replacing the gravity-flotation scheme with a purely flotation scheme made it possible to obtain scheelite concentrate containing 68-70% WO3 with a recovery of 90% (according to the gravity-flotation scheme, the recovery was 50%). Much attention in Lately is focused on improving extraction technology tungsten minerals from sludge in two main directions: gravitational enrichment of sludge on modern multi-deck concentrators (similar to the enrichment of tin-containing sludge) with subsequent finishing of the concentrate by flotation and enrichment on wet magnetic separators with high tension magnetic field(for wolframite sludge).
An example of the use of combined technology is factories in China. The technology includes sludge thickening to 25-30% solids, sulfide flotation, tailings enrichment in centrifugal separators. The resulting rough concentrate (WO3 content 24.3% with recovery 55.8%) is sent to wolframite flotation using organophosphorus acid as a collector. Flotation concentrate containing 45% WO3 is subjected to wet magnetic separation to obtain wolframite and tin concentrates. Using this technology, wolframite concentrate containing 61.3% WO3 with a recovery of 61.6% is obtained from sludge containing 0.3-0.4% WO3. Thus, technological schemes for the enrichment of tungsten ores are aimed at increasing the complexity of the use of raw materials and separating all associated valuable components into independent types of products. Thus, at the Kuda factory (Japan), when enriching complex ores, 6 commercial products are obtained. In order to determine the possibility of additional extraction useful components from stale enrichment tailings in the mid-90s. TsNIGRI studied a technological sample containing 0.1% tungsten trioxide. It has been established that the main valuable component in the tailings is tungsten. The content of non-ferrous metals is quite low: copper 0.01-0.03; lead - 0.09-0.2; zinc -0.06-0.15%, gold and silver were not found in the sample. Studies have shown that successful extraction of tungsten trioxide will require significant costs for regrinding the tailings and at this stage their involvement in processing is not promising.
The technological scheme of mineral processing, including two or more devices, embodies everything character traits complex object, and optimization of the technological scheme can apparently constitute the main task of system analysis. Almost all previously discussed modeling and optimization methods can be used to solve this problem. However, the structure of concentrator plant circuits is so complex that it is necessary to consider additional methods optimization. Indeed, for a circuit consisting of at least 10-12 devices, it is difficult to implement a conventional factorial experiment or carry out multiple nonlinear statistical processing. Currently, several ways to optimize circuits are being outlined - an evolutionary path to generalize the accumulated experience and take a step in the successful direction of changing the circuit.
Pilot testing of the developed technological scheme for the enrichment of general waste and an industrial plant
The tests were carried out in October-November 2003. During the tests, 15 tons of initial mineral raw materials were processed in 24 hours. The results of testing the developed technological scheme are presented in Fig. 3.4 and 3.5 and in table. 3.6. It can be seen that the yield of the standard concentrate is 0.14%, the content is 62.7% with a WO3 recovery of 49.875%. The results of spectral analysis of a representative sample of the obtained concentrate are given in table. 3.7, confirm that W-concentrate III of magnetic separation is standard and complies with the KVG (T) grade of GOST 213-73 “Technical requirements (composition,%) for tungsten concentrates obtained from tungsten-containing ores.” Consequently, the developed technological scheme for the extraction of W from the stale tailings of the ore processing of the Dzhida VMC can be recommended for industrial use and stale tails transferred to additional industrial mineral raw materials of the Dzhida VMC.
For the industrial processing of stale tailings using the developed technology at Q = 400 t/h, a list of equipment has been developed, given in To carry out an enrichment operation with a particle size of +0.1 mm, it is recommended to install a KNELSON centrifugal separator with continuous unloading of the concentrate, while for centrifugal enrichment class -0.1 mm must be carried out on a KNELSON centrifugal separator with periodic unloading of the concentrate. Thus, it has been established that the most effective way extraction of WO3 from general waste with a particle size of -3+0.5 mm is carried out by screw separation; from size classes -0.5+0.1 and -0.1+0 mm and primary enrichment tailings crushed to -0.1 mm - centrifugal separation. The essential features of the technology for processing stale tailings from the Dzhida VMC are as follows: 1. A narrow classification of the feed directed to primary enrichment and finishing is necessary; 2. An individual approach is required when choosing a method for primary enrichment of classes of different sizes; 3. Obtaining waste tailings is possible with the primary enrichment of the finest feed (-0.1+0.02mm); 4. Use of hydrocycloning operations to combine dewatering and size separation operations. The drain contains particles with a particle size of -0.02 mm; 5. Compact arrangement of equipment. 6. Profitability of the technological scheme (APPENDIX 4), the final product is a standard concentrate that meets the requirements of GOST 213-73.
Kiselev, Mikhail Yurievich
The main tungsten minerals are scheelite, hübnerite and wolframite. Depending on the type of minerals, ores can be divided into two types; scheelite and wolframite (huebnerite).Scheelite ores in Russia, as well as in some cases abroad, are enriched by flotation. In Russia, the process of flotation of scheelite ores in industrial scale carried out before the Second World War at the Tyrn-Auz factory. This plant processes very complex molybdenum-scheelite ores containing a number of calcium minerals (calcite, fluorite, apatite). Calcium minerals, like scheelite, float with oleic acid; the depression of calcite and fluorite is produced by stirring in a liquid glass solution without heating (long-term contact) or with heating, as at the Tyrn-Auz factory. Instead of oleic acid, fractions of tall oil are used, as well as acids from vegetable oils (reagents 708, 710, etc.) alone or in a mixture with oleic acid.
A typical flotation scheme for scheelite ore is shown in Fig. 38. Using this scheme, it is possible to remove calcite and fluorite and obtain tungsten trioxide-standard concentrates. However, apatite still remains in such quantity that the phosphorus content in the concentrate is higher than standard. Excess phosphorus is removed by dissolving apatite in weak hydrochloric acid. Acid consumption depends on the calcium carbonate content in the concentrate and is 0.5-5 g of acid per ton of WO3.
When leaching with acid, part of the scheelite, as well as powellite, is dissolved and then precipitated out of solution in the form of CaWO4 + CaMoO4 and other impurities. The resulting dirty sludge is then processed according to the I.N. method. Maslenitsky.
Due to the difficulty of obtaining quality tungsten concentrate, many factories abroad produce two products: a rich concentrate and a poor one for hydrometallurgical processing into calcium tungstate using the method developed in Mekhanobra I.N. Maslenitsky, - leaching with soda in an autoclave under pressure with transfer into solution in the form of CaWO4, followed by purification of the solution and precipitation of CaWO4. In some cases, with coarsely disseminated scheelite, finishing of flotation concentrates is carried out on tables.
From ores containing a significant amount of CaF2, extraction of scheelite by flotation has not been developed abroad. Such ores, for example in Sweden, are enriched on tables. Scheelite, entrained with fluorite in the flotation concentrate, is then separated from this concentrate on the table.
In Russian factories, scheelite ores are enriched by flotation, obtaining quality concentrates.
At the Tyrn-Auz plant, concentrates containing 6% WO3 are produced from ore containing 0.2% WO3 with a recovery of 82%. At the Chorukh-Dairon plant, with ore of the same VVO3 content, 72% WO3 is obtained in concentrates with an extraction of 78.4%; at the Koytash plant, with ore with 0.46% WO3 in concentrate, 72.6% WO3 is obtained with a WO3 recovery of 85.2%; at the Lyangarsky plant in ore 0.124%, in concentrates - 72% with extraction of 81.3% WO3. Additional recovery of poor products is possible by reducing losses in tailings. In all cases, if sulfides are present in the ore, they are separated before scheelite flotation.
The consumption of materials and energy is illustrated by the data below, kg/t:
Wolframite (Hübnerite) ores are enriched exclusively by gravity methods. Some ores with uneven and coarse-grained dissemination, such as Bukuki ore (Transbaikalia), can be pre-enriched in heavy suspensions, releasing about 60% waste rock with a particle size of 26+3 MM with a content of no more than 0.03% WO3.
However, with a relatively low productivity of factories (no more than 1000 tons/day), the first stage of enrichment is carried out in jigging machines, usually starting with a particle size of about 10 mm for coarsely disseminated ores. In new modern schemes, in addition to jiggers and tables, Humphrey screw separators are used, replacing part of the tables with them.
A progressive scheme for the enrichment of tungsten ores is shown in Fig. 39.
The finishing of tungsten concentrates depends on their composition.
Sulfides from concentrates thinner than 2 mm are separated by flotogravity: the concentrates, after mixing with acid and flotation reagents (xanthate, oils), are sent to a concentration table; The resulting CO2 concentrate is dried and subjected to magnetic separation. The coarse concentrate is pre-crushed. Sulfides are separated from fine concentrates from slurry tables by foam flotation.
If there are a lot of sulfides, it is advisable to separate them from the discharge of hydrocyclones (or classifier) before enrichment on the tables. This will improve the conditions for the release of wolframite on tables and during concentrate finishing operations.
Typically, rough concentrates before finishing contain about 30% WO3 with recovery up to 85%. For illustration in table. 86 shows some data on factories.
During the gravitational enrichment of wolframite ores (Hübnerite, ferberite) from slurries thinner than 50 microns, the recovery is very low and the losses in the slurry part are significant (10-15% of the content in the ore).
From sludge by flotation with fatty acids at pH=10 it is possible to further extract WO3 into lean products containing 7-15% WO3. These products are suitable for hydrometallurgical processing.
Wolframite (Hübnerite) ores contain a certain amount of non-ferrous, rare and noble metals. Some of them pass during gravity enrichment into gravity concentrates and are transferred to finishing tailings. From sulfide finishing tailings, as well as from sludge, molybdenum, bismuth-lead, lead-copper-silver, zinc (they contain cadmium, indium) and pyrite concentrates can be isolated by selective flotation, and the tungsten product can also be isolated.
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The invention relates to a method complex processing tailings from the enrichment of tungsten-containing ores. The method includes their classification into small and large fractions, screw separation of the fine fraction to obtain a tungsten product and its cleaning. In this case, re-cleaning is carried out on a screw separator to obtain a rough tungsten concentrate, which is refined on concentration tables to obtain a gravity tungsten concentrate, which is subjected to flotation to obtain a high-grade conditioned tungsten concentrate and a sulfide-containing product. The tailings of the screw separator and the concentration table are combined and subjected to thickening. In this case, the waste obtained after thickening is fed to the classification of tailings for the enrichment of tungsten-containing ores, and the thickened product is subjected to enrichment in a screw separator to obtain secondary waste tailings and a tungsten product, which is sent for cleaning. The technical result is to increase the depth of processing of tungsten-containing ore tailings. 1 salary files, 1 table, 1 ill.
The invention relates to the beneficiation of minerals and can be used in the processing of tailings from the enrichment of tungsten-containing ores.
When processing tungsten-containing ores, as well as their tailings, gravitational, flotation, magnetic, as well as electrostatic, hydrometallurgical and other methods are used (see, for example, Bert P.O., with the participation of K. Mills. Gravity enrichment technology. Translated from English. - M.: Nedra, 1990). Thus, for the preliminary concentration of useful components (mineral raw materials), photometric and lumometric sorting (for example, the Mount Carbine and King Island concentration plants), enrichment in heavy environments (for example, the Portuguese Panasquera factory and the English Hemerdan factory) are used. ), jigging (especially of poor raw materials), magnetic separation in a weak magnetic field (for example, to separate pyrite, pyrrhotite) or high-intensity magnetic separation (to separate wolframite and cassiterite).
For the processing of tungsten-containing sludge, the use of flotation is known, in particular wolframite in China and at the Canadian Mount Pleasade factory, and in some factories flotation has completely replaced gravity enrichment (for example, the Jokberg factories, Sweden and Mittersil, Austria).
It is also known to use screw separators and screw sluices for the enrichment of tungsten-containing ores, old dumps, stale tailings, and sludge.
For example, when processing old dumps of tungsten ore at the Cherdoyak factory (Kazakhstan), the initial dump material, after crushing and grinding to a size of 3 mm, was subjected to enrichment on jiggers, the under-sieve product of which was then cleaned on a concentration table. The technological scheme also included enrichment in screw separators, in which 75-77% of WO 3 was recovered with a yield of enrichment products of 25-30%. Screw separation made it possible to increase the extraction of WO 3 by 3-4% (see, for example, Anikin M.F., Ivanov V.D., Pevzner M.L. “Screw separators for ore dressing”, Moscow, Nedra publishing house ", 1970, 132 pp.).
The disadvantages of the technological scheme for processing old dumps are the high load at the head of the process for the jigging operation, insufficiently high WO 3 extraction and a significant yield of enrichment products.
There is a known method for the associated production of tungsten concentrate by processing molybdenite flotation tailings (Climax Molybdenum factory, Canada). Tailings containing tungsten are separated using screw separation into tungsten waste sludge (light fraction), primary wolframite - cassiterite concentrate. The latter is subjected to hydrocyclonation and the sludge discharge is sent to the waste tailings, and the sand fraction is sent to the flotation separation of pyrite concentrate containing 50% S (sulfides) and discharged into the waste tailings. The chamber product of sulfide flotation is purified using screw separation and/or cones to obtain waste pyrite-containing tailings and wolframite-cassiterite concentrate, which is processed on concentration tables. In this case, wolframite-cassiterite concentrate and waste tailings are obtained. After dehydration, the crude concentrate is cleaned sequentially by purifying it from iron using magnetic separation, removing monazite from it by flotation (phosphate flotation) and then dewatering, drying, classifying and separating using stage magnetic separation into a concentrate containing 65% WO 3 after stage I and 68% WO 3 after stage II. A non-magnetic product is also obtained - tin (cassiterite) concentrate containing ~35% tin.
This processing method has disadvantages - complexity and multi-stage nature, as well as high energy intensity.
There is a known method for additional extraction of tungsten from gravity enrichment tailings (Boulder plant, USA). Gravity enrichment tailings are further crushed and deslimed in a classifier, the sands of which are separated using hydraulic classifiers. The resulting classes are enriched separately on concentration tables. Coarse tailings are returned to the grinding cycle, and fine tailings are thickened and re-enriched on slurry tables to produce a finished concentrate, middlings sent to regrinding, and tailings sent to flotation. The main flotation concentrate is subjected to one cleaning. The original ore contains 0.3-0.5% WO 3; Tungsten recovery reaches 97%, with about 70% of tungsten recovered by flotation. However, the tungsten content in the flotation concentrate is low (about 10% WO 3) (see, Polkin S.I., Adamov E.V. Enrichment of non-ferrous metal ores. Textbook for universities. M., Nedra, 1983, 213 pp.)
The disadvantages of the technological scheme for processing tailings from gravity enrichment are the high load at the head of the process on the enrichment operation on concentration tables, multi-operation, and low quality of the resulting concentrate.
There is a known method for processing scheelite-containing tailings in order to remove hazardous materials from them and process non-hazardous and ore minerals using an improved separation process (KR 20030089109, CHAE et al., 11/21/2003). The method includes the stages of homogenizing mixing of scheelite-containing tailings, introduction of the pulp into the reactor, “filtration” of the pulp using a screen to remove various foreign materials, subsequent separation of the pulp by screw separation, thickening and dehydration of non-metallic minerals to produce a cake, drying the cake in a rotary dryer, crushing the dry cake using a hammer crusher operating in a closed cycle with a screen, separation of crushed minerals using a “micron” separator into fractions of fine and coarse grains (granules), as well as magnetic separation of the coarse-grained fraction to obtain magnetic minerals and a non-magnetic fraction containing scheelite. The disadvantage of this method is the multi-operation nature and the use of energy-intensive drying of the wet cake.
There is a known method for additional extraction of tungsten from the waste tailings of the concentrating plant of the Ingichki mine (see A.B. Ezhkov, Kh.T. Sharipov, K.L. Belkov “Involvement in the processing of stale tungsten-containing tailings of the Ingichki mine.” Abstracts of reports of the III Congress of concentrators of the CIS countries, vol.1, MISiS, M., 2001). The method includes preparing the pulp and desliming it in a hydrocyclone (removal class - 0.05 mm), subsequent separation of the deslimed pulp on a cone separator, two-stage re-cleaning of the cone separator concentrate on concentration tables to obtain a concentrate containing 20.6% WO 3 with an average recovery 29.06%. The disadvantages of this method are the low quality of the resulting concentrate and insufficiently high WO 3 extraction.
The results of research on the gravitational enrichment of tailings from the Ingichkinsky enrichment plant are described (see S.V. Rudnev, V.A. Potapov, N.V. Salikhova, A.A. Kanzel “Research on the selection of the optimal technological scheme for the gravitational enrichment of man-made formations at the Ingichkinsky enrichment plant "//Mining Bulletin of Uzbekistan, 2008, No. 3).
The closest to a patented technical solution is a method for extracting tungsten from stale tailings of the enrichment of tungsten-containing ores (Artemova O.S. Development of technology for extracting tungsten from stale tailings of the Dzhida VMC. Abstract of the dissertation of a candidate of technical sciences, Irkutsk State Technical University, Irkutsk, 2004 - prototype).
The technology for extracting tungsten from stale tailings using this method includes the operations of obtaining rough tungsten-containing concentrate and middling product, gold-bearing product and secondary waste tailings using gravitational methods of wet enrichment - screw and centrifugal separation - and subsequent finishing of the resulting rough concentrate and middling product using gravitational (centrifugal) enrichment and magnetic separation to obtain a conditioned tungsten concentrate containing 62.7% WO 3 with a recovery of 49.9% WO 3 .
According to this method, stale tailings are subjected to primary classification with the release of 44.5% of the mass. into secondary tailings in the form of a +3 mm fraction. The tailings fraction with a particle size of -3 mm is divided into classes -0.5 and +0.5 mm, and from the latter, coarse concentrate and tailings are obtained using screw separation. The -0.5 mm fraction is divided into classes -0.1 and +0.1 mm. From the +0.1 mm class, a coarse concentrate is separated using centrifugal separation, which, like the coarse concentrate of screw separation, is subjected to centrifugal separation to obtain rough tungsten concentrate and a gold-containing product. The tailings of screw and centrifugal separation are further crushed to -0.1 mm in a closed cycle with classification and then divided into classes -0.1+0.02 and -0.02 mm. The -0.02 mm grade is removed from the process as secondary tailings. Class -0.1+0.02 mm is enriched by centrifugal separation to produce secondary tailings and tungsten middlings, sent for finishing by magnetic separation along with the centrifugal separation concentrate, ground to a size of -0.1 mm. In this case, tungsten concentrate (magnetic fraction) and middling product (non-magnetic fraction) are obtained. The latter is subjected to magnetic separation II with the release of a non-magnetic fraction into secondary tailings and tungsten concentrate (magnetic fraction), which is enriched sequentially by centrifugal, magnetic and again centrifugal separation to obtain standard tungsten concentrate containing 62.7% WO 3 with a yield of 0.14 % and recovery 49.9%. In this case, the tailings of centrifugal separations and the non-magnetic fraction are sent to secondary tailings, the total yield of which at the stage of finishing the rough tungsten concentrate is 3.28% with a content of 2.1% WO 3.
The disadvantages of this method are the multi-operational nature of the technological process, which includes 6 classification operations, 2 additional grinding operations, as well as 5 centrifugal and 3 magnetic separation operations using relatively expensive equipment. At the same time, finishing the crude tungsten concentrate to the required standard is associated with the production of secondary waste tailings with a relatively high tungsten content (2.1% WO 3).
The objective of the present invention is to improve the method of processing enrichment tailings, including stale tailings from the enrichment of tungsten-containing ores, to obtain high-grade tungsten concentrate and an associated sulfide-containing product while reducing the tungsten content in the secondary waste tailings.
The patented method for complex processing of tailings from the enrichment of tungsten-containing ores includes classification of tailings into small and large fractions, screw separation of the fine fraction to obtain a tungsten product, re-cleaning of the tungsten product, and finishing to obtain high-grade tungsten concentrate, sulfide-containing product and secondary waste tailings.
The method differs in that the resulting tungsten product is subjected to re-cleaning on a screw separator to obtain rough concentrate and tailings, the rough concentrate is subjected to finishing on concentration tables to obtain gravitational tungsten concentrate and tailings. The tailings of the concentration table and the cleaning screw separator are combined and subjected to thickening, then the thickening discharge is fed to the classification stage at the head of the technological scheme, and the thickened product is subjected to enrichment on a screw separator to obtain secondary tailings and a tungsten product, which is sent for cleaning. The gravity tungsten concentrate is subjected to flotation to obtain a high-grade tungsten concentrate (62% WO 3) and a sulfide-containing product, which is processed by known methods.
The method can be characterized by the fact that the tailings are classified into fractions, mainly with a size of +8 mm and -8 mm.
The technical result of the patented method is to increase the depth of processing while reducing the number of technological operations and the load on them due to the separation at the head of the process of the bulk of the initial tailings (more than 90%) into secondary waste tailings, using energy-saving screw separation technology that is simpler in design and operation. This makes it possible to dramatically reduce the load on subsequent enrichment operations, as well as capital and operating costs, which ensures optimization of the enrichment process.
The effectiveness of the patented method is shown using the example of complex processing of tailings from the Ingichkinsky enrichment plant (see drawing).
Processing begins with the classification of tailings into small and large fractions with the separation of secondary waste tailings in the form of a large fraction. The fine fraction of the tailings is subjected to screw separation with the separation of the bulk of the original tailings (more than 90%) at the head of the technological process into secondary waste tailings. This allows for a correspondingly dramatic reduction in downstream workload, capital costs and operating costs.
The resulting tungsten product is subjected to re-cleaning using a screw separator to obtain rough concentrate and tailings. The rough concentrate is subjected to finishing on concentration tables to obtain gravity tungsten concentrate and tailings.
The tailings of the concentration table and the cleaning screw separator are combined and subjected to thickening, for example, in a thickener, mechanical classifier, hydrocyclone and other devices. The condensation discharge is fed to the classification stage at the head of the technological scheme, and the condensed product is subjected to enrichment in a screw separator to obtain secondary tailings and a tungsten product, which is sent for cleaning.
The gravity tungsten concentrate is brought by flotation to a high-grade tungsten concentrate (62% WO 3) to obtain a sulfide-containing product.
Thus, high-grade (62% WO 3 ) conditioned tungsten concentrate is isolated from tungsten-containing tailings upon achieving a relatively high WO 3 extraction of ~49% and a relatively low tungsten content (0.04% WO 3 ) in the secondary waste tailings.
The resulting sulfide-containing product is processed in a known manner, for example, it is used to produce sulfuric acid and sulfur, and is also used as a corrective additive in the production of cements.
High-grade tungsten concentrate is a highly liquid commercial product.
As follows from the results of implementing the patented method using the example of stale tailings from the enrichment of tungsten-containing ores from the Ingichkinsky concentrating plant, its effectiveness is shown in comparison with the prototype method (see table). Provided additional receipt sulfide-containing product, reducing the volume of fresh water consumed by creating a water cycle. It creates the possibility of processing significantly poorer tailings (0.09% WO 3), a significant reduction in the tungsten content in secondary waste tailings (up to 0.04% WO 3). In addition, the number of technological operations has been reduced and the load on most of them has been reduced due to the separation at the head of the technological process of the bulk of the initial tailings (more than 90%) into secondary waste tailings, using a simpler and less energy-intensive screw separation technology, which reduces capital costs for the purchase of equipment and operating costs.
1. A method for complex processing of tailings from the enrichment of tungsten-containing ores, including their classification into small and large fractions, screw separation of the fine fraction to produce a tungsten product, its re-cleaning and finishing to produce high-grade tungsten concentrate, sulfide-containing product and secondary waste tailings, characterized in that the resulting after screw separation, the tungsten product is subjected to re-cleaning on a screw separator to obtain rough tungsten concentrate, the resulting rough tungsten concentrate is subjected to finishing on concentration tables to obtain gravity tungsten concentrate, which is subjected to flotation to obtain high-grade conditioned tungsten concentrate and sulfide-containing product, tailings of the screw separator and concentration table are combined and subjected to thickening, the resulting waste after thickening is fed to the classification of tailings for the enrichment of tungsten-containing ores, and the thickened product is subjected to enrichment in a screw separator to obtain secondary waste tailings and a tungsten product, which is sent for cleaning.
Vladivostok
annotation
This paper discusses technologies for the enrichment of scheelite and wolframite.
The technology for enriching tungsten ores includes: preliminary concentration, enrichment of crushed products of preliminary concentration to obtain collective (rough) concentrates and their finishing.
Keywords
Scheelite ore, wolframite ore, heavy-medium separation, jigging, gravity method, electromagnetic separation, flotation.
1. Introduction 4
2. Pre-concentration 5
3. Technology of enrichment of wolframite ores 6
4. Technology of enrichment of Scheelite ores 9
5. Conclusion 12
References 13
Introduction
Tungsten is a silver-white metal with high hardness and a boiling point of about 5500°C.
Russian Federation has large explored reserves. Its tungsten ore potential is estimated at 2.6 million tons of tungsten trioxide, of which proven reserves amount to 1.7 million tons, or 35% of those in the world.
Developed deposits in the Primorsky Territory: Vostok-2, OJSC Primorsky GOK (1.503%); Lermontovskoye, OJSC Lermontovskaya GRK (2.462%).
The main tungsten minerals are scheelite, hübnerite and wolframite. Depending on the type of minerals, ores can be divided into two types; scheelite and wolframite (huebnerite).
When processing tungsten-containing ores, gravitational, flotation, magnetic, as well as electrostatic, hydrometallurgical and other methods are used.
Pre-concentration.
The cheapest and at the same time highly productive methods of preconcentration are gravitational ones, such as heavy-medium separation and jigging.
Heavy medium separation allows you to stabilize the quality of food entering the main processing cycles, to isolate not only the waste product, but also to separate the ore into rich coarsely disseminated and poor finely disseminated ore, which often require fundamentally different processing schemes, since they differ markedly in material composition. The process is characterized by the highest density separation accuracy compared to other gravitational methods, which allows for high recovery of the valuable component with minimal concentrate yield. When enriching ore in heavy suspensions, a difference in the densities of the separated pieces of 0.1 g/m3 is sufficient. This method can be successfully used for coarsely disseminated wolframite and scheelite-quartz ores. The results of studies on the enrichment of tungsten ores from the Pun-les-Vignes (France) and Borralha (Portugal) deposits under industrial conditions showed that the results obtained using enrichment in heavy suspensions are significantly better than when enriching only on jig machines - into the heavy fraction recovery was more than 93% of the ore.
Jigging compared to heavy-medium enrichment requires less capital costs, allows you to enrich material in a wide range of densities and sizes. Coarse jigging has become widespread in the beneficiation of coarse and medium disseminated ores that do not require fine grinding. The use of jigging is preferable when enriching carbonate and silicate ores of skarn and vein deposits, while the value of the ore contrast index in terms of gravitational composition should exceed one.
Technology of enrichment of wolframite ores
The high specific gravity of tungsten minerals and the coarse-grained structure of wolframite ores make it possible to widely use gravitational processes in their enrichment. To obtain high technological indicators, it is necessary to combine devices with different separation characteristics in a gravitational scheme, in which each previous operation in relation to the subsequent one is, as it were, a preparatory operation, improving the enrichment of the material. A schematic diagram of the enrichment of wolframite ores is shown in Fig. 1.
Jigging is used starting from the size at which tailings can be recovered. This operation is also used to isolate coarse tungsten concentrates with subsequent regrinding and enrichment of jigging tails. The basis for choosing the jigging scheme and the size of the enriched material is the data obtained by separating the material by density with a particle size of 25 mm. If the ores are finely disseminated and preliminary studies have shown that large-piece enrichment and jigging are unacceptable for them, then the ore is enriched in thin suspension-carrying flows, which include enrichment on screw separators, jet chutes, cone separators, sluices, and concentration tables. With stage-by-stage grinding and stage-by-stage enrichment of ore, the extraction of wolframite into rough concentrates is more complete. Rough wolframite gravity concentrates are brought to condition according to developed schemes using wet and dry enrichment methods.
Rich wolframite concentrates are enriched by electromagnetic separation, and the electromagnetic fraction can be contaminated with ferrous zinc blende, bismuth minerals and partially arsenic (arsenopyrite, scorodite). To remove them, magnetizing roasting is used, which enhances the magnetic susceptibility of iron sulfides, and at the same time, sulfur and arsenic, which are harmful to tungsten concentrates, are removed in the form of gaseous oxides. Wolframite (Hübnerite) is further extracted from sludge by flotation using fatty acid collectors and the addition of neutral oils. Rough gravity concentrates are relatively easily brought to condition using electrical enrichment methods. Flotation and flotation gravity are carried out with the supply of xanthate and a foaming agent in a slightly alkaline or slightly acidic environment. If the concentrates are contaminated with quartz and light minerals, then after flotation they are cleaned on concentration tables.
Related information.