RUSSIAN RARE EARTH METAL RAW MATERIALS:PROSPECTS FOR THE DEVELOPMENT OF MINERAL RESOURCES

*L.Z. Bykhovsky

All-Russian Scientific-Research Institute of Mineral Resources named after N.M. Fedorovsky (FSUE "VIMS")Staromonetny per. 31, Moscow, Russia119017

(*Corresponding author: lev@vims-geo.ru)

ABSTRACT

Due to the sharp increase in demand for rare-earth materials in the world market, their Russian mineral resources are considered. Ranging of possible sources of rare-earth raw materials on terms of their involvement in industrial development is executed. It is noted that the mineral resources of rare earth metals existing in Russia can not only satisfy completely predicted requirements of the domestic industry, but also will allow entering on the world market with rare-earth production as the large player.

KEYWORDS

Russia rare earth resources, Lovozersk, Katuginsk, Tomtor, Chuktukon, Khibine apatite, Tugansk, Yakutiya, prospective deposits, processing

INTRODUCTION

The rare earth metals (REM) representing today the greatest interest from all types of mineral raw middle levelmaterials for the industry caused real "rare-earth boom" around the world. Fourteen elements of the lanthanum group (lanthanides) and yttrium belong to REM. Based on the physical and chemical and technological properties they are subdivided into cerium (4 elements – lanthanum, cerium, praseodymium, neodymium) and yttrium groups (10 lanthanides – samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium) (Arkhangelskaya, Lagonsky, Usova, & Chistov, 2006). It is also used the division of REM into lights (4 elements of cerium group), medium (6 elements of yttrium group – from Sm to Нo), heavy (4 elements of yttrium group – Er, by Tm, Yb, Lu and Y). Sometimes samarium and europium (Lavrenchuk & Dyomin, 2012) belong to cerium (light) group. The standard division of rare earths is absent. Sometimes scandium also belongs to rare earths.

The use of REM began at the beginning of the XX century, developed fast rates, and now totaling over 100 fields of application. Their most part is used in the form of the mixed compounds, oxides and a misch metal (an alloy on the basis of REM) as catalysts for oil cracking, in production of glass and ceramics, and also in metallurgy. Prior to the beginning of the `90s, more than 95% of consumption were the share of these scopes, but in the last 20 years of REM began to be applied actively in hi-tech knowledge-intensive areas where individual REM, their oxides and connections are used. Level of application of REM, as well as the majority of other rare metals, is an indicator of scientific and technical level and competitiveness of the industry of the country (Arkhangelskaya, Lagonsky, Usova, & Chistov, 2006; Bykhovsky, Arkhangelskaya, & Tigunov, 2008; Usova & Konin, 2008).

At the beginning of 1990 the world output of REM was estimated at 40 thousand tons, now it is ~ 125 thousand tons, by 2020 180-200 Kt are expected. In 1989 in the USSR about 8.5 Kt of REM oxides were produced (the 3rd place in the world on their production and export). Now production of rare earths in the form of carbonate is reduced to 1.5-2 Kt (1.5% of world production). Final productions on release of individual REM remained outside of Russia – in Estonia, Kazakhstan and Kyrgyzstan. Current and expected needs of the Russian industry for REM, including individual rare earths, are unknown. According to various estimates, the requirement for 2020 makes from 6-8 to 20 thousand tons/year.

Jump of interest in REM is caused in recent years not only all by the increasing their application in hi-tech sector of world economy, but also policy of the People's Republic of China – the monopolist in production of rare-earth raw materials who delivered it many years at the dumping prices of the world market (95% of world requirement) that led to closing the many rare-earth enterprises around the world. However in 2010-2011 the People's Republic of China considerably reduced export of rare-earth raw materials, on what the world market reacted jump the prices (at 5-10 times and more). Now the prices are stabilize, and it is already obvious that they will not reach peak values of 2011. For separate REM, first for cerium and lanthanum, also further reduction of prices is possible.

Many countries (USA, Australia, Greenland (Denmark), Canada, Japan, Republic of South Africa, Kazakhstan, Kyrgyzstan, India, Vietnam, Democratic People's Republic of Korea, etc.) were beginning revitalize or create new capacities for production and processing of REM.

Requisite of reconstruction of REM industry sector became apparent and for Russia. Orientation of the country leaders to innovative development promoted to creation within the "Development of the Industry and Increase of Its Competitiveness" program of the State subprogramme "Development of the industry of rare and rare-earth metals" (it is approved as the Resolution of the Government of the Russian Federation No. 328 of 15.04.2014). A few workshops were held on a topic of rare and rare earth metals. In different scientific and technical domestic magazines tens articles on rare-earth subject are published. In 2013 issue of the Rare Earths magazine where the special attention is paid to a reconstruction of the rare-earth industry of Russia is begun.

Expansion of application of REM provides progress in many spheres of the industry as promotes creation of essentially new technologies, materials, devices, technical devices. Growth of volumes of consumption of many rare-earth metals makes now 10-15% a year: the share of individual REM in consumption actively and steadily grows, but demand for separate elements develops unevenly. Among them are the most demanded: neodymium, europium, cerium, lanthanum, praseodymium, samarium and yttrium. Consumption of terbium, dysprosium, erbium, gadolinium and scandium grows.

It should be noted that unique properties of scandium cause interest in many industries and first of all in military industrial complex (Cherny, 2013). In particular, Sc additive in aluminum alloys to 0.3% increases their durability by 3 times, and they become capable to a welding, corrosion firmness, a malleability improve and the area of working temperatures almost increases twice. Superalloy (aluminum with 2% of scandium) takes root into modern aircraft and space equipment and is a part of solid oxide fuel elements (SOFE).

Areas of application of scandium oxides, metal and its compounds are rather diverse. Today scandium is the most expensive of all REM. The price of Sc2O3 (99.5%) makes ~ the $3000/kg.

The first "scandium boom" was in the late fifties – the beginning of the 1960th. In 1960 the resolution of Council of ministers of the USSR on development in the country of the scandium industry was accepted (it was planned to production 7 t a year Sc2O3 to 1965). As a result, the USSR took the 1st place in the world in production of scandium (in 1980 – to a maximum of 10 t a year). At this time, annual release of Sc2O3 in the rest of the world was estimated at 500 kg.

The second "scandium boom" was in the second half of 1980 when the State Program of large-scale production of scandium from domestic raw materials was developed (in 2002-2005 were planned to make about 50 t of Sc2O3 and 1000 t aluminum-scandium ligature per year). After collapse of the USSR, production of scandium was sharply reduced. Excessive demand for scandium, however as well as on other REM, in the early nineties is explained, in particular, by aspiration of banks and some companies to use it as world currency (Bykhovsky, Arkhangelskaya, Tigunov, & Anufriyeva, 2007).

Now again interest in scandium sharply increased. The volume of the world market of scandium is estimated at 15-20 t today. It is possible to assume that the world is on a threshold of the third "scandium boom". Large-scale use of scandium restrains its high price.

The variety of possible raw sources of scandium, and identification of complex fields with the increased concentration of Sc2O3 (~ 500 g/t) allow to count for significant increase in its production and respectively reduction of prices of scandium raw materials.

With regard to the already explored reserves of rare earth metals (REM), Russia is in second place in the world (TR2O3with reserves of 28 million tonnes). All the 17 deposits included in the State Balance of Mineral Reserves are complex. REMs are present there either as associated components (9 apatite deposits (8 at Khibine Mountains and one at Seligdarskoye in Yakutia), 1 titanium (Yaregskoye in the Komi Republic), 1 niobium-phosphoric (Beloziminskoye at the Irkutsk region) and 1 zirconium-niobium-tantalum deposits (Ulug-Tanzekskoye in the Republic of Tyva)) or as one of the main components (4 complex Nb-, Ta- and TR-containing deposits (Lovozersk, Katuginsk, Tomtor and Chuktukon) and one technogenic deposit containing Au and REM (Fig. 1)). The deposits, except for Lovozersk, are considered as having the potential for industrial exploitation. The perspectives for their development will rely on the achievements in the development of innovative ore processing technologies.

Figure 1 – REM deposits of Russia

Deposits of apatite ores include 80,9% of stocks ΣTR2O3 of the categories A+B+C1; 57,1% of the category A+B+C1+C2. In mltimetal REM deposits together with niobium, frequent tantalum, sometimes zirconium, scandium, cryolitas, etc., are enclosed 2,4% of stocks ΣTR2O3 of the categories A+B+C1; 42,8% of the category A+B+C1+C2. The structure of stocks of REM of Russia is shown in Fig. 2.

Now from the 17 deposits included in the State Balance, the Lovozerskoye complex REM deposit and 7 nepheline-apatite ores deposits in Khibine Mountains are developing. It is annually taken from a mineral resources and more than 80 Kt of REM oxides are derecognising off from the State Balance. In the present article attempt to range possible sources of REM raw materials on terms of their involvement in industrial development is made.

Among the deposits included in the State Balance, potential deposits with author's stocks and objects with the expected resources (approved and author's), and it is possible to distinguish real, potential and perspective sources of rare-earth raw materials from technogenic mineral formations.

Figure 2 – Structure of reserves of rare-earth metals of Russia as of 01.01.2015

Real sources of REM is the developing (Lovozerskoye, 8 deposits in Khibine Mountains) and explorated and prepared for industrial development deposits. The State Balance consider reserves of REM of these deposits, and deposits are in the distributed fund of mineral resources (Katuginskoye) or are offered for auctions (Kular technogenic ore placer).

The Lovozerskoye deposit in Murmansk region is developed since 1951. This is a large multimetal deposit (Та, Nb,TR, Ti), loparite ores of that contain at average, %: TR2O3 – 1.12; Та2O5 – 0.02; NЬ2O5 –0.24; TiO2 –1.29; Sг – 0.08. Development of a field is conducted by JSC Lovozersky GOK with receiving the loparite concentrate, containing, %: TR2O3 – 30.5-36; Та2O5 –0.6-0.7; Nb2O5–7.3-8.7; SrO –1.0-3.0; TiO2 –39.0-40.4; ThO2 –0.5-0.7.

JSC Solikamsk Magnesian Plant in Perm Krai carries out processing of a concentrate with receiving carbonates of rare earths, tantalum and niobium pentoxides, and titanium dioxide. Lovozerskoye deposit only in Russia from which ores rare earths are taken. The Lovozersky GOK works for 1/4 design capacities with low economic efficiency now. REM carbonates made by it practically entirely are sent for export. Metals of ceric group prevail (98%) as a part of REM. Increase in power of Lovozersky GOK to 1 million t of ore a year (in 2012 314 Kt of ore were get and processed at design capacity of 455 Kt) perhaps when involving in development of the Alluaiv site of a deposit and doubling of refinery capacities. Considering a difficult economic situation of GOK, its state support will be required (in the form of concessional loans and other preferences).

Other real sources of REM are apatite concentrates from Khibiny nepheline-apatite deposits (Arkhangelskaya, Lagonsky, Usova, & Chistov, 2006; Bykhovsky, Arkhangelskaya, & Tigunov, 2008; Golubev, 2014).

In Russia in 2014 were mine 84.6 Kt of TR2O3, including 2.2 Kt from the loparite ores of the Lovozerskoye deposit and 82.4 Kt from 7 Khibiny deposits of apatite ores. REM from apatite ores in Russia are almost not taking today, but they can be considered as a perspective source of raw materials of both ceric and yttric group. Now pilot plant for extraction TR from the apatite concentrates is constructed in Chepetsk town. Concentrates are processed according to the sulphuric-acid scheme (from EFK where

passes ~ 50-60% of TR2O3, and the rest in a phosphite), power - 12 tons/year of TR2O3. Building of similar pilot plant for extraction of TR from apatite concentrates comes to the end. Processing will be by the carbonitric scheme in Novgorod town (power – 200 tons/year of TR2O3).

Figure 3 – The scheme of complex use of concentrates at different systems of their uncovering

Processing of apatite concentrates is made by two technologies – carbonitric and sulphuric-acid (~80% of concentrates). Complex carbonitric processing gives the chance to receive a concentrate of REM and strontium (Fig. 3) along with nitric and phosphate fertilizers.

To the middle of 1980 rare earths were taken when processing the Khibinium apatite concentrates at two enterprises of Minsredmash (Ministry of Medium Machine Building) of the USSR, and in GDR, Poland and Norway. After an entry into the world market cheap Chinese rare-earth raw materials, production of REM was stopped (Bykhovsky, Arkhangelskaya, & Tigunov, 2008). When processing by a sulphuric-acid method, ~ 50-60% of REMs pass into a phosphogypsum (wastes of processing of an apatite concentrate which collects in significant amounts, polluting environment). Today the considerable attention is drawn by a problem of complex use of a phosphogypsum with receiving a wide range of nonmetallic production, strontium and REM. Works are conducted by IHTREMS, VIMS, VNIIHT and other organizations. Recovery of REM from extraction phosphoric acid (40%) is also possible (see Fig. 3).

In view of stable structure of the Khibinium apatite concentrate containing about 1% of TR2O3 and huge volumes of processing of these raw materials; it is possible to claim that its complex processing would allow to cover practically any needs of the industry for rare-earth metals and strontium and to provide their export. Structure of rare earths on individual elements are those metals and their connections, which are in the greatest demand in the sphere of high technologies and have a high price in the world market. The content of yttric group REM ~ 10%. Possible volumes of products at complex processing of apatite concentrates of the Khibiny deposits are presented in Tale. 1. The close contents of TR2O3 are considered also in apatites of the Beloziminskoye and Seligdarskoye deposits in the Republic of Sakha (Yakutia). Both deposits are in the undistributed fund of mineral resources.

Table 1 – Possible product output at complex processing of apatite concentrates from Khibiny deposits

Annual output of apatiteconcentrate

Volume ofproduction,

Mt

Salable production output, KTA

TR2O3 SrO Fluoride

Carbonitric process(REM oxides recovery – 60%) Up to 1-1.5 6-9 15-22 20-30

Sulphuric-acid process(REM oxides recovery – 40%) 7-8.5 28-34 42-51 -

Total 8-10 34-43 57-73 20-30

Real source of REM is the Katuginskoye complex deposit of the REM ores (Nb, Ta, TR, etc.) in alkaline metasomatita, which is in details explorated and being in the distributed fund. It is located in Zabaykalsky Krai in 24 km from the railway station Cheena. There are two industrial types of ores at the deposit – tantalum and yttrium, which stocks of useful components are counted: in tantalum (cut-off grade – 0.006% of Ta2O5), in yttrium (cut-off grade – 0.1%Y2O3) (Mashkovtsev, Bykhovsky, Rogozhin, & Temnov, 2011; Lepeshkin, 2014).

By quantity of the stocks, explorated in a contour of a pit the deposit belongs to very large, and taking into account stocks behind a pit contour to unique. The average contents of Ta2O5 and Nb2O5 in reserves of tantalum ores of the categories B+C1 makes 0.02 and 0.347% respectively. On the category C2,

reserves of rare-earth metals at the average content of 0.348% of TR 2O3 are counted, including 0.16% of Y2O3. In the same ores on the C2 category of ZrO2 stocks at the average content of 1.6% of ZrO2, and cryolite are counted. In yttrium ores the main useful components are rare earths with the stocks counted on the category C2 with the average content of 0.59% of TR2O3, including yttrium – 0.19% of Y2O3. The content of other useful components – Ta, Nb, Zr – low, as well as their stocks in these ores are insignificant.

VIMS in the 1970th developed and checked in trial scale technology of enrichment of ores with receiving pyrochlore (Nb, Ta), zirconium (Zr) and gagarinit-yttrium-fluorite (TR) concentrates. The technology can be improved. Advantage of the object is a high share of yttrium group (~ 50%) in the REM-concentrate and its confinedness to the mining knot of the region, including Udokanskoye copper and Chineyskoye Ti-Fe-V and Pd-Cu, Apsatsky coal deposits, etc. Possibilities of production of REM and other marketable products during the development of multimetal REM deposits are illustrated in Table 2.

The real resources of REM are the monazite concentrates of the State reserve (82 thousand tons), which are stored in Krasnoufimsk, Sverdlovsk region; monazite from complex Ti-Zr placers of the Tuganskoye deposit in the Tomsk region; kularit (a kind of a monazite with the raised content of europium and the low content of thorium) from the technogenic placer (the tails of concentrating of gold-bearing placer in the Kularsky area of the Republic of Sakha (Yakutia)). Possible production from the monazite concentrates is shown in Table 3.

Table 2 – Possible product output at the development of Ta, Nb, TR deposits

Deposit Processingcapacity, KTA

Salable production output, TPATR2O3 Ta2O5 Nb2O5 other

Lovozerskoye 500 3300 70 870 TiO2 - 4200

Katuginskoye 600 ( 1 st stage) 3000 (2nd stage)

13705700

62230-250

11504800

ZrO2 – 6900-20000

Tomtorskoye 10 ( 1 st stage) 30 (2nd stage)

6902070 - 580

1740Sc2O3 –3.8-11.4

Chuktukonskoye 150 3100 1300 MnO2 – 10000

Total 8460 ( 1 st stage) 14170 (2nd stage)

132 ( 1 st stage) 300-320 (2nd

stage)

3900 ( 1 st stage) 8710 (2nd stage) -

Table 3 – Possible product output from the monazite concentrates at the development of placers (State reserve)

Source ofconcentrate

Monazite reserves

/ TR2O3, Kt

Annual monazite

output / TR2O3, t

Remarks

State reserve (Krasnoufimsk) 7240

4000-80002000-4000 -

The tails of concentrating of gold-bearing placer in the Kularsky area of the Republic of Sakha (Yakutia) and gold-kularit placers

>6~3

(1.3 Kt on the State reserve)

540270

at processing 250 thousand m3 of sand a year (Giredmet, 1990)

Tuganskoye titanium-zircinium deposit 6331

~40002000

at production of 4 million m3 a year (The feasibility study, 1991)

Total 14374

8540-125404270-6270 -

Potential sources of REM is the deposits, on which exploration and appraisal works are complete, are developed temporary standards, reserves are approved by GKZ and considered by the State Balance, expediency of carrying out exploration of a prospecting stage on them is proved (Tomtorskoye and Chuktukonskoye deposits). On prognostic resources and author's reserves of a deposit are estimated as large and unique, however on the reserves included in the State Balance it is small deposits today with unique high concentration of REM and Nb. Industrial (large-scale) development of these deposits can be carried out after end of a exploration stage, trial production, development of technology of processing of ores and receiving commodity products with a high value added. For carrying out exploration on this deposits, the approval of the Feasibility study and materials of calculation of the reserves will be required at least 3 years, on the subsequent drawing up and the approval of the engineering design of development of the deposits - about 3 years. Respectively the minimum term for a little large-scale development of these deposits will make not less than 6-7 years.

The Tomtorskoye deposit is located in the north of the Republic of Sakha (Yakutia), in economically undeveloped area, in 110 km from the Ebelyakh settlement. mineralization is localized in the derivative residuum of carbonatites. Main ore minerals: pyrochlore, monazite, xenotime, crandallite (Arkhangelskaya, Lagonsky, Usova, & Chistov, 2006; Bykhovsky, Arkhangelskaya, & Tigunov, 2008; Tolstov, Konoplev, & Kuzmin, 2011).

Evaluation work has been carried out at the Buranny site. Reserves were counted at the cut-off grade 3.5% of Nb2O5 and make about 9% of the general reserves of ores of site. The reserves of dry ore approved by GKZ on the categories B+C1 – 1.2 Mt, Nb2O5 – 79 thousand tons, Y2O3 – 7 thousand tons, Sc2O3 – 560 t, Ln2O3 – 112 thousand tons. Contents, %: Nb2O5 – 6.71; Y2O3 – 0.595; Sc2O3 – 0.048; Ln2O3

– 9.53. (Calculations are executed for dry ore at humidity in a subsoil of 21.13%). At statement of reserves to the State Balance humidity of ore and therefore the contents of passing components is respectively lowered was considered and make, in particular, for the sum of REM oxides (including Y 2O3) 7.98% that is reflected in separate publications (Usova & Konin, 2008). Prognostic resources on the Buranny site – 100 Mt of ore on the category P1, at the contents, %: TR2O3 – 8.2; Nb2O5 – 1.5; Sc2O3 – 0.05. In 2014, on the Buranny site the through license for additional exploration and development is granted. Now exploration is actively conducted, trial production of ores begins.

The Chuktukonskoye deposit is located in Krasnoyarsk Krai. Due to prognostic resources and author's reserves of the category C2 a deposit is unique. The approved reserves total ~ 5% of the general resources of a deposit. Mineralization is connected with laterization of carbonatites (Lomayev & Serdyuk, 2011). The main ore minerals – monazite, florencite, bastite, pyrochlore, pyrolusite, hydrogoethite. Reserves were counted at the cut-off grade of TR2O3 – 3%. Average content, %: Nb2O5 – 0.99 (in the

approved reserves – 0.60), TR2O3 – 5.11-5.34 (in the approved reserves 7.32), MnO – 4.4-5.0. Prospects of development of a deposit depend on implementation of the project of development of Lower Angara region. It is also necessary to pin a label on the potential the explorated deposits, included in the State Balance and which are in state unallocated subsoil reserve fund – multimetal REM Beloziminskoye, Ulug-Tanzekskoye and apatite Seligdarskoye, which development is improbable soon. The reserves of the Yaregskoye deposit would be rational to discharge from the State Reserves Register because of low concentration of REM in the leucoxene and the absence of commercially viable recovery method.

Perspective sources of rare-earth raw materials - potential deposits, mineral occurrences and technogenic formations, which industrial value is determined by preliminary technical and economic calculations or for an expert assessment, reserves (resources) are authentically not established and often are not approved. Technological study is often based on unpresentable tests or is not complete. Additional appraisal of these objects, their feasibility study and statement of reserves on the state account are necessary.

Among prospective target, it is possible to notice the Kiyskoye rare-earth potential deposit, organogenic-phosphatic uranium-REM ores of Kalmykia, a perofskite-titanium magnetite ores of Afrikanda deposit, orthite ores of the Uzhno-Bogatyrskoye potential deposit and some other, and eudialyte concentrates of Khibine Mountains and metal-bearing coals. Technogenic formations can also become perspective sources of receiving REM: red muds - waste of aluminum production and a phosphogypsum - waste of processing of apatite concentrates by sulphuric-acid technology.

Opportunity and economic feasibility for extraction of scandium and REM from red muds were discussed nearly half a century more (Bykhovsky & Rozov, 1965) back and then it was noted that it is possible only in case of utilization of the most part of this waste, which more than 200 Mt are saved up. Only in 2013. IK RUSAL have output on Uralsk aluminum plant a pilot scale batch of production with use of red muds – furnace addition. In 2014, receiving primary scandium concentrate is planned. Installation power on its receiving will make 2 tons/year.

Condition of profitable use of these formations is development waste-free (or low-waste) technology at which REM will be one of the main or passing useful components. Now OMK "Skaygrad" is developed and patented technology for processing of a phosphogypsum with recovery from it construction materials and a rare-earth concentrate. Project works for creation of the industrial module for processing of 20 Kt of a phosphogypsum a year (Rare earths come to the end. - 2013. - No. 1. - Page 101).

CONCLUSIONS

In summary, it should be noted, that the market of a REM collective concentrate in Russia is absent. Many experts note need for creation of technology and a choice of the equipment for division of a REM collective concentrate, and respectively and the enterprise (enterprises) for release of rare-earth production of the 3-4th extent of repartition. Only the vertically integrated complex including receiving a concentrate of REM and its processing in end products can be effective. Rare earths, scandium and other rare metals can become for Russia the same, than oil and gas are today.

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