Alternate Approaches to Recover Zircon Mineral Sand from Beach Alluvial Placer Deposits and Badlands

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Alternate Approaches to Recover Zircon Mineral Sand from Beach Alluvial Placer Deposits and Badlands Topography for Industrial Applications Sunita Routray1, Tumula Laxmi2and Raghupatruni Bhima Rao3 C V Raman College of Engineering, Bhubaneswar 752 054, India CSIR‐Institute of Minerals and Materials Technology, Bhubaneswar 751 013, India 3Aryan Institute of Engineering and Technology, Bhubaneswar 752 050, India 1 2

sunitaroutray77@gmail.com, 2tumulalaxmi@gmail.com, 3bhimarao@gmail.com

1

Abstract At present, recovery of zircon from beach sand and red sediments of badlands topography is a priority due to high demand of zircon for industrial applications. Zircon content in these deposits varies from 0.2% to 2.7% by weight. Results of these studies reveal that heavy mineral content in the beach‐dune sand is 16.7%, in which the zircon is 0.16 %. Red sediment contains 33.2% heavy minerals in which the zircon is 0.32%. A common flowsheet with material balance is suggested to recover zircon by wet process and in combination of wet and dry process. Zircon concentrate recovered from beach‐dune sand contains 98.0% zircon with 79.6% recovery. The results of pre‐concentration of heavy minerals by judicious combination of magnetic separator and advanced air classifier reveal that about 63% of light heavy minerals can be rejected by which the use of fresh water in spirals can be minimized. Zircon concentrate recovered by traditional approach of India from red sediment sample contains 96.3% of zircon with 84.3% recovery and zircon recovered from alternate approach is 97.9% grade with 79.5% recovery. In depth characterization of zircon and their value addition is suggested.

Keywords Beach and Dune Sands; Red Sediments; Badlands Topography; Total heavy Minerals; Zircon; Flowsheet

Introduction Zircon has been recognised as a valuable material because of its combination of physical and mechanical properties, such as excellent chemical stability, thermal shock resistance, strength retention at high temperatures and low thermal expansion and heat conductivity (Singh, 1990). High zircon demand has made the exploitation of zircon enriched deposits as a priority. Beach and dune sand deposits and red

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sediments of badland topography are reported to be potential sources of heavy minerals (Indian Minerals Year book, 2008; Laxmi and Bhima Rao, 2010). Hence, it has attracted the attention of scientists, engineers and users to exploit zircons from these deposits and in depth characterizations for end use.

Zircon is used in industry with a wide range of applications, as zircon sand directly from the mine; as a milled product in the form of zircon flour (95% micronized to less than 45μm used in the manufacturing of frit) and opacifier grade (100% micronized to less than 6μm, used in ceramic glazes for tiles and sanitary wares). The most important market for zircon is as an opacifier for ceramic titles and sanitary ware. Zircon finds its application in ceramics (54%) and refractory industries (14%), which accounts for 68% of zircon’s total world consumption of 1.2 million tonnes. The rest (32%) is consumed in foundry, TV glass, zirconia chemicals and other applications (Murty et al., 2007).

Lean placer deposits containing 2–5% Total Heavy Minerals (THMs) are first concentrated to 20–30% THMs by cone concentrators. The general practice to recover zircon from the Indian beach sands involves complicated flowsheet with processes such as gravity separation, magnetic separation, electrostatic separation and flotation (Bhima Rao et al., 2009). In India, the IMMT has also developed few flow sheets for different placer deposits to recover zircon by using different unit operations (Bhima Rao et al., 2002; 2006; 2008; 2009). This product is then fed to spirals, which may give a concentrate of more than 80% THMs from which zircon is separated. Some of the Australian industries employing spirals, magnetic separators,

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electrostatic separators, pneumatic and hydraulic tables achieved concentrates of +95% grades of rutile and zircon, respectively, from feeds as low as 0.2% of the combined minerals in beach sand (Technology in Australia, 1988). Kelsey reported that to reduce the Al2O3 content to acceptable levels in the zircon product from kyanite‐containing minerals, a Kelsey jig will probably be required, as the spirals alone will be unable to make a satisfactory separation between the two minerals (Jones and Erasmus, 1999).

A significant problem in mineral processing industries demands for fresh water. Water demand already exceeds supply in many parts of the world and as the world population continues to rise, so does the water demand. In view of this, pre concentration of heavy minerals by dry process may be alternate approach to solve the scarcity for fresh water. Thus wet circuits of mineral processing industries can be replaced (wherever possible) by dry circuits using air fluidized bed separators or air classifier or any advanced unit operations. Such unit operations may be installed anywhere in the circuit, regardless of water supply. In most cases, dry processing plants increase capacity, cuts down number of units and space necessary, resulting in smaller and less expensive plants with lower power costs of heavy minerals of beach sand by dry method, which is a priority area.

In this paper, an attempt is made on recovery of zircon from beach‐dune sand and red sediments samples and the results are discussed.

Materials and Methods Raw Material

meters. Total ten beach and ten dune sand samples were collected covering about 7 kilometers distance.

All the samples were thoroughly mixed and a sub sample was prepared for characterization and composite sample for beneficiation studies to recover zircon. Recovered zircons were characterized in detail for industrial applications.

[A]Concentration of ilmenite along the shore

[B]Typical dune deposits away from shore

FIG. 1 TYPICAL TOPOGRAPHICAL VIEW OF BEACH SAND AND ALONG THE COAST AT KONARK‐RAMACHANDI BEACH AREA, ODISHA, INDIA

2) Red Sediments from Basanputti Village, Odisha About one ton of sample was collected from red sediments of badlands topography of Basanputti village, Ganjam Dist, Orissa, India (Lat.19o21’N and Long. 85o03’E). Typical red sediment sample of badlands topography of Basanputti village, Ganjam Dist., Orissa is shown in Fig. 2. Samples were collected by channels along the foot hills and grab samples were collected from the field. All samples were thoroughly mixed and representative sub samples were used for characterization studies and the composite sample was subjected for beneficiation studies to recover zircon. Recovered zircons were characterized in detail.

Raw materials were collected from Konark‐Ramachandi coastal stretch, Puri district, Orissa, India and red sediments of badland topography of Basanputti village, Ganjam district, Odisha, India.

1) Beach and Dune Sands from Konark‐ Ramachandi Coastal Stretch Beach and dune sand samples were collected along Konark –Ramchandi areas, Puri district, Orissa, India (Lat.17o49’‐22o34’N and Long.81o29’‐87o29’E).

The coastal beach plain extends from the ocean edge to the river Kusabhadra which joins the Bay of Bengal Sea.

Characterization Studies of Feed Samples

Typical topographical view of beach sand and dune sand along the coast at Konark‐Ramachandi beach area is shown in Fig. 1. Beach and dune sand samples were collected in a grid pattern at an interval of 700

Physical characteristics such as bulk density, true density, apparent porosity, angle of repose, size analyses and sink‐float analyses were carried out for both composite beach‐dune sand and red sediment

FIG. 2 TYPICAL SEDIMENTS OF BADLAND TOPOGRAPHY SHOWING CONCENTRATION OF HEAVY MINERALS AREA: BASANPUTTI VILLAGE, GANJAM DIST, ODISHA, INDIA

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samples.

Beneficiation Studies Beneficiation studies of both beach sand and red sediment sample were carried out by alternate approaches.

Beneficiation Studies on Beach‐dune Sand Composite Sample

separator to obtain reject able coarse material. The cut size of the VSK separator was determined. Fine fractions from VSK separator contain mostly sillimanite, rutile, zircon etc while as rejectable coarse fraction contains mainly quartz, feldspar and pyriboles. The fine fraction is subjected to gravity table, flotation cell and high tension separator for recovery of zircon.

TABLE 1 DESIGN OF EXPERIMENTS FOR COMPOSITE SAND SAMPLE USING VSK SEPARATOR

Beneficiation studies were carried out following both wet and dry route. Both the methods are explained below.

Wet Method The composite beach‐dune sand sample was subjected to a laboratory model, Humphrey’s spiral concentrator, supplied by M/s. Humphreys Mineral Industries, Inc., Denver, USA with 17½” pitch used to recover total heavy minerals (~ 98% grade). The concentrate was then subjected to Wet High Intensity Magnetic Separator (WHIMS) to recover magnetic heavies and non‐magnetic heavies separately. The non magnetic fraction contains mostly sillimanite, zircon, rutile, quartz etc. The non magnetic fraction was subjected to gravity table. The concentrate from gravity table was subjected to flotation cell to separate sillimanite. The flotation tailing was subjected to High Tension Separator (HTS) to recover zircon in non conducting fraction.

All products and tailings obtained from spiral concentrator, magnetic, flotation and HTS units were subjected to sink and float tests to assess the quality of the products.

Dry Method Pre‐concentration of heavy minerals from a composite beach sand sample was done by using VSK separator‐ an advanced air cyclone, model no. SKS VS 10.4, M/s Humboldt Wedag India, The representative sample was subjected to Dry High Intensity Magnetic Separator (developed by ELB‐YANTV and supplied by Ore Sorters, Australia Pty., Ltd) to separate magnetic minerals from non magnetics. The non magnetic fraction was subjected to a series of VSK separator.

Continuous VSK separator studies were carried out at different operating conditions such as cage wheel speed, feed rate (screw feeder ‐ rpm), air rate (Fan, Hz.) to get the desired cut size, as given in Table 1.

The first stage coarse material was further targeted to second stage VSK separator to obtain clean coarse material and fine material. Similarly, the second stage coarse material was subjected to third stage VSK

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Beneficiation Studies on Red Sediment Sample Scrubbing and desliming of red sediment sample was carried out using a high speed impeller conditioner followed by a hydrocyclone. The slimes were rejected and the sand was used for further studies to recover total heavy minerals followed by recovery of individual heavy minerals. Deslimed feed sample was subjected to laboratory model, Humphrey’s spiral concentrator used to recover total heavy minerals (~98% grade). Beneficiation studies include recovery of zircon by two alternative methods of wet process.

1) Traditional Approach In India The concentrate obtained from number of stage spirals was subjected to High Tension Separator (HTS) to recover conducting and non conducting fractions separately. The non conducting fraction contains mainly zircon, sillimanite and quartz. The non conducting fraction was subjected to gravity table. The concentrate from gravity table was subjected to flotation cell to separate out sillimanite as concentrate and zircon as tailing.

2) Alternate Approach The concentrate obtained from number of stage spirals was subjected to Wet High Intensity Magnetic Separator (WHIMS) to recover magnetic heavies and non‐magnetic heavies separately. The non magnetic fraction contains mostly sillimanite, zircon, rutile, quartz etc. The non magnetic fraction

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was subjected to gravity table. The concentrate from gravity table was subjected to flotation cell to separate sillimanite. The flotation tailing subjected to High Tension Separator (HTS) to recover zircon in non conducting fraction. The recovered zircon minerals from both the sources were subjected to chemical and mineralogical analyses.

Results and Discussion Physical Characterization of Composite Beach Sand Samples

Typical result on size analysis followed by sink‐float studies on close size fractions for beach‐dune sample is presented in Table 3. The data reveal that the coarser fraction +600 μm also contains small amount of total heavy minerals. Maximum percent of THM accumulated at below 100 μm size fraction is 93.5% by weight. The modal analysis of the sample given in Fig.3 shows that the sample contains 0.16% zircon, 7.37% ilmenite, 5.26% garnet, 3.33% sillimanite, 0.15% rutile, 0.43% other heavy minerals and 83.3% quartz.

Physical characterization of composite beach‐dune sand sample is given in Table 2. The bulk and true densities of the sample are 1.7 and 2.8 g/cm3 respectively. The d80 passing size of the sample shows a value of 430 μm. The THM content of the sample is 16.7% out of which Total Magnetic Minerals (TMM) content is 12.74% by weight.

TABLE 2 PHYSICAL PROPERTIES OF COMPOSITE BEACH‐DUNE SAND SAMPLE

FIG. 3 MODEL ANALYSIS OF KONARK‐RAMACHANDI SAMPLE

Beneficiation Studies 1) Recovery of Zircon from the Composite Beach‐ Dune Sand Sample by Wet Method Zircon concentrate which is recovered in the non conducting fraction (obtained from gravity table concentrate followed by flotation tailings and HTS) contains 98.0% zircon with 79.6% recovery. The conceptual flow sheet with material balance on recovery of zircon is shown in Fig. 4.

TABLE 3 TYPICAL RESULTS ON SIZE ANALYSIS FOLLOWED BY SINK‐FLOAT STUDIES ON CLOSE SIZE FRACTIONS OF COMPOSITE BEACH‐DUNE SAND SAMPLE

FIG. 4 FLOW SHEET WITH MATERIAL BALANCE TO RECOVER ZIRCON CONCENTRATE FROM COMPOSITE BEACH‐DUNE SAND SAMPLE OF KONARK‐RAMACHANDI BEACH

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2) Recovery of Zircon from the Composite Beach‐ Dune Sand Sample by Dry Method Summary of results on continuous VSK separator studies at different operating conditions such as cage wheel speed, feed rate (screw feeder ‐ rpm), air rate (Fan, Hz.) is given in Table 4.

TABLE 4 SUMMARY OF THE RESULTS OF VSK SEPARATOR AT LARGE SCALE CONTINUOUS OPERATION

TABLE 5 SIZE ANALYSES OF VSK PRODUCTS AND PARTITION FACTORS

(CAGE WHEEL: 1000, SCREW FEEDER: 1200)

most frequently use is Ep value (probable error) defined as half of difference between the sizes at which 75% and 25% recoveries are observed: 0.5 . Here the calculated Ep value is 80. It is observed from these results that the best operating condition achieved for a cut size of 215 μm is at a cage wheel speed of 1000 rpm, screw feeder 1200 rpm and air rate at 49 Hz. It is essential to explain the principle of operation of VSK separator (Manual of VSK separator, Humboldt Wedag Limited, 2005) for mineral sand.

The principle of operation is self explanatory in Fig 6. The raw sand enters to the V‐Separator at a controlled rate from hopper via an electro‐magnetic tube feeder by gravity. The actual classification takes place between the array of steps and an opposing array of baffle plates. Classifying air enters this space transversely to the material flow, dragging the fine fraction in between the classifying baffles to the exit for fines and air. The coarse fraction mostly contains lighter minerals, quartz and light heavy minerals such as pyroboles, sillimanite etc, which cascades to the bottom discharge of the classifier. The cascading movement causes repeated impact on the passing material.

Only the remaining fine fraction is passed on for further processing in a cage wheel separator and to a classifying cyclone. The result is helpful to separate liberated fine particles containing mostly heavy minerals and super fines which are air lifted from the VS fines out to cyclone by cage wheel operation for efficient separation.

FIG. 5 PARTITION CURVE FOR VSK PRODUCTS (UNDER CONDITIONS OF CAGE WHEEL 100RPM, SCREW FEEDER 1200RPM)

The percentage of coarse responded from the feed vs. average size in microns plotted to determine the effective size separation of VSK unit. Typical data is presented in Table 5 and partition curve is plotted in Fig. 5. The sharpness of the cut depends on the slope of the central section of the partition curve.

The closer the vertical to the slope is; the higher the efficiency is. The cut size or d50 value found from the curve is 215 μm. For the partition curve, the

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FIG. 6 PRINCIPLE OF OPERATION OF ADVANCED AIR CYCLONE (VSK separator‐static and dynamic separator with cyclone)

A flowsheet with material balance on pre‐concentration of zircon by judicious combination of dry high intensity magnetic separator and advanced air cyclone (VSK Separator) is shown in Fig. 7. The

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content of sample enriches 33.2%. The downstream sample of red sediments contains 71.8% of total heavy minerals. Physical characterization of stream sample of red sediment is given in Table 6.

XRD data shown in Fig. 8 of the 3rd stage coarse fraction (rejectable tailings) indicate that the sample contains mostly quartz and the light heavy minerals are mostly pyriboles.

TABLE 6 PHYSICAL PROPERTIES OF RED SEDIMENT STREAM SAMPLE

TABLE 7 RESULTS OF SINK‐FLOAT STUDIES ON CLOSE SIZED FRACTIONS OF

RED SEDIMENT SAMPLE

FIG. 7 RECOVERY OF HEAVY MINERALS FROM BEACH SAND USING DRY MAGNETIC SEPARATOR AND VSK AIR CYCLONE

FIG. 8 XRD PATTERN OF REJECTABLE COARSE FRACTION

Thus by judicious combination of DHIMS and VSK about 63% of light (<2.9 sp.gr minerals) and light heavy minerals (>2.9 <3.3 sp. gr) can be rejected by which the use of fresh water in the primary circuit of mineral separation plant can be minimized. Fine fractions obtained in all three stages of VSK operation are subjected to further downstream process for recovery of individual heavy minerals.

It is estimated from the present spiral concentration studies that about 150 liters of water per one ton of sand sample can be saved in dry process using advanced air cyclone.

Physical Characterization of Red Sediment Sample The red sediment sample initially contains 20.4% of total heavy minerals associated with 28.1% slimes.

After desliming, the Total Heavy Minerals (THM)

FIG. 9 MODEL ANALYSIS OF RED SEDIMENT SAMPLE OF BASANPUTTI VILLAGE, GANJAM DIST., ODISHA

The bulk and true densities of the sample are 1.92 and 3.42 g/cm3 respectively. The d80 passing size of the sample shows a value of 278 μm. The THM content of the sample is 71.8% out of which Total Magnetic Minerals (TMM) content is 62.7% and Total Non magnetic Minerals (TNM) content is 9.1%. Typical result on size analysis followed by sink‐float studies on close size fractions for beach‐dune sample is presented in Table 7. The data reveal that the total heavy minerals are distributed maximum in size

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fractions. Maximum percent of THM is accumulated at below 300 μm size fraction 86.9% by weight. The modal analysis of heavy minerals present in the red sediment samples of Basanputti is shown in Fig. 9. The data reveal that the THM of red sediment sample contains 0.32% zircon, 28.7% ilmenite, 3.32% sillimanite, 0.23% rutile and 0.61% of other minerals.

Beneficiation Studies on Red Sediment Sample Summary of results on continuous spiral test for development of flow sheet with material balance are given in Table 8 and Fig. 10. The data indicate that the concentrate (Product‐total heavy minerals) contains 32.8% by weight with 97.2% THM and 96.1% recovery.

The rejectable tailings contain 65.9% weight with 1.7% THM.

HTS to recover zircon concentrate as a non conducting fraction which contains 8.7% by weight and 3.54% zircon with 96.4% recovery. The conducting fraction contains only 0.02% zircon. The non conducting fraction is subjected to gravity table to remove quartz. The concentrate from gravity table contains mainly sillimanite and zircon (4.48% zircon and 93.9% recovery). The tailings contain 0.4% zircon.

After four stage flotation, the tailing fraction (zircon) contains 96.79% zircon with 78.6% recovery. The froth from flotation cell contains only 0.74% zircon.

The details of above results with material balance can clearly be seen in flow sheet shown in Fig. 11.

TABLE 8 SUMMARY OF SPIRAL RESULTS ON RECOVERY OF THM FROM RED SEDIMENTS

FIG. 11 FLOW SHEET WITH MATERIAL BALANCE ON RECOVERY OF ZIRON BY DRY METHOD FROM RED SEDIMENTS OF BASANPUTTI VILLAGE, GANJAM DIST., ODISHA

4) Alternate Approach

FIG. 10 FLOW SHEET WITH MATERIAL BALANCE TO RECOVER TOTAL HEAVY MINERALS FROM RED SEDIMENTS OF BASANPUTTI VILLAGE, GANJAM DIST., ODISHA

3) Traditional Approach in India The concentrate from stage spirals is subjected to

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The red sediment sample of Basanputti village, Orissa contains 0.32% zircon out of 33.2% THM. Results of beneficiation studies carried out on beach sand by using spirals, WHIMS, flotation, gravity table and HTS for recovery of zircon are discussed. The concentrate from stage spirals has 32.8% by weight which contains 0.945% zircon with 96.9% recovery. The rejectable tailing contains only

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0.015% zircon. Results of WHIMS on concentrate obtained in spiral concentrator reveal that 4.1% non magnetic contain 7.07% zircon with 90.6% recovery.

Magnetic fraction which is 28.7% by weight contains only 0.07% zircon. The concentrate from gravity table contains 7.52% zircon with 84.6% recovery. Gravity table concentrate is subjected to two stage flotation, where flotation tailing fraction contains 56.91% zircon with 80.0% recovery. The non conducting fraction, zircon obtained from HTS contains 97.89% zircon with 79.5% recovery. The details of above results with material balance can clearly be seen in flow sheet shown in Fig. 12.

both beach‐dune and red sediment samples are presented in Table 10. The data indicate that d80 passing size of beach sand zircon is 202 μm while as d80 passing size of red sediment zircon is 182 μm.

Thus, it is clearly indicated that the beach‐dune sand zircon is coarser than red sediment zircon.

TABLE 9 PHYSICAL PROPERTIES OF ZIRCON CONCENTRATE

TABLE 10 WET SIZE ANALYSIS OF ZIRCON CONCENTRATE OBTAINED FROM COMPOSITE BEACH‐DUNE SAND SAMPLE AND RED SEDIMENTS

2) Modal Analysis Beach sand zircon concentrate constitute 98.0% of zircon, 0.7% rutile, 0.5% sillimanite and 0.8% other minerals. Modal analysis of red sediment zircon shows that the zircon concentrate contains 98.1% of zircon, 0.6% rutile, 0.9% sillimanite and 0.4% other minerals. Thus the data indicate that zircon obtained from both the resources is good quality and suitable for industrial applications.

FIG. 12 FLOW SHEET WITH MATERIAL BALANCE ON RECOVERY OF ZIRON BY WET METHOD FROM RED SEDIMENTS OF BASANPUTTI VILLAGE, GANJAM DIST., ODISHA

Characterisation of Zircon Concentrate 1) Physical Characterization The physical properties of zircon concentrate obtained from composite beach‐dune sand and red sediment samples are shown in Table 9. The bulk and true densities for beach sand zircon are 2.74 g/cm3 and 4.67 g/cm3 respectively. Red sediment zircon also shows approximately the same values for bulk and true densities. The wet size analysis of

3) Chemical Characterization The wet chemical analysis of beach sand and red sediment zircon is presented in Table 11. The data indicates that the ZrO2% of beach sand zircon is 63.33% by weight which is slightly higher than ZrO2% of red sediment zircon (62.7%). The HfO2 content for beach sand and red sediment zircon is 1.2% and 0.9% respectively.

TABLE 11 WET CHEMICAL ANALYSIS OF BEACH SAND AND RED SEDIMENT ZIRCON

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4) SEM/EDAX Morphology of zircons of beach sand and red sediment samples seen under SEM is shown in Figs.

13 and 14. The analysis shows major contents of zircon and silicon in zircon minerals of various strengths. The result reveals that Zr content ranging from 48.24% to 58.63% in weight while as Si content ranging from 16.8% to 25.31% for beach sand zircon.

In case of red sediment zircon, Zr varies from 39.67% to 55.36% and Si varies from 17.52% to 23.67%.

water per one ton of sand sample can be saved in dry process using advanced air cyclone.  The red sediment sample contains 33.2% total heavy minerals (THM), out of which zircon content is 0.32%.  Zircon concentrate recovered by traditional approach from red sediment sample contains 96.79% of zircon with 78.6% recovery while as zircon recovered from alternate approach is 97.89% grade with 79.5% recovery.  Beach sand zircon shows 63.33% of ZrO2, whereas red sediment zircon shows 62.7% ZrO2.

FIG. 13 SEM‐EDAX OF ZIRCON RECOVERED FROM COMPOSITE BEACH‐DUNE SAND SAMPLE

 U and Th contents of red sediment zircon sample are 364 ppm and 0.7% respectively, whereas for beach sand zircon U and Th (322 ppm and 0.05% respectively) contents are much higher than those of red sediment zircon sample.  Due to the presence of these radioactive elements, the metamictization effect is more significant in red sediment zircon than beach sand zircon.

FIG. 14 SEM‐EDAX OF ZIRCON RECOVERED FROM RED SEDIMENT SAMPLE

Conclusions The following conclusions are drawn from the beneficiation and characterization studies of beach sand zircon and red sediment zircon.  Composite Konark–Ramachandi beach‐dune sand sample contains 16.7% total heavy minerals out which zircon content is 0.16%.  Zircon concentrate recovered from beach‐dune sand contains 98.0% zircon with 79.6% recovery.  Beach‐dune sand zircon concentrate contains 98.0% of zircon, 0.7% rutile, 0.5% sillimanite and 0.8 % other minerals.  The results of pre‐concentration of heavy minerals by judicious combination of DHIMS and VSK separator reveal that about 63% of light and light heavy minerals can be rejected by which the use of fresh water in spirals can be minimized.  It is estimated from the present spiral concentration studies that about 150 liters of

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 The REE abundance in the red sediment zircon sample indicates that La, contains 10630 ppm whereas beach sand zircon contain La, 93 ppm.

Similarly, the Ce contains 16980 ppm for red sediment zircon and 238 ppm for beach sand zircon.  The other REE trend is significantly high in red sediment zircon from beach sand zircon.  The summary of the data indicates that red sediment zircon contains significant radioactive and REE compared to beach sand zircon.

Hence utilization of these red sediment zircon minerals may be restricted to use in Pressurized Heavy Water Reactors (PHWR).

ACKNOWLEDGMENTS

The authors are thankful to the Director, Institute of Minerals and Materials Technology (CSIR), Bhubaneswar for giving permission to use laboratory facilities. One of the authors Ms. Tumula Laxmi is thankful to BRNS for granting Senior research fellowship.

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Dr Sunita Routray, is working as a Assistant Professor at C. V. Raman college of Engineering, Bhubaneswar, India. She was awarded Ph D in the area of Mineral processing from ITER, SOA University, Bhubaneswar, India. She carried out her research work as SRF under BRNS project at Institute of Minerals and Materials Technology (CSIR) Bhubaneswar. She obtained her Bachelor’s degree in engineering (Metallurgical and Material Science) from Utkal University, Orissa. She joined as a lecturer in Material Science Department at J.J.T.M. Paralakhemundi, Orissa. She worked as Research Intern at Institute of Minerals and Materials Technology, Bhubaneswar prior to joining as SRF. To her credit, she has a few publications in seminars and journals.

Er Tumula Laxmi, has been working as a CSIR‐SRF in Advanced Materials Technology department at CSIR‐IMMT, Bhubaneswar, India from 1st April 2013.

She passed B.Tech, Chemical Engg., during 2002 from JITM, Paralakhemundi, Berhampur University, Orissa, India.

Since then she has taught and involved in R&D for invention. Initially, she started her career as a lecturer to teach Chemical Engg., to the Polytechnical students at UGIE, Rourkela. Later, she moved to the Utkal University, Bhubaneswar to teach the undergraduate pharmacists.

Subsequently, she joined at JITM, Paralakhemundi, Orissa as a lecturer in the department of Chemical Engg. Then, she got an opportunity to join as a Senior Research Fellow under BRNS Project (Dept. of Atomic Energy), Bombay at CSIR‐ IMMT during 2010 prior to join as a CSIR‐SRF. She registered for Ph D at SOA University, Bhubaneswar, India during 2010. To her credit, she holds a few publications in seminars and journals.

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www.ijm‐me.org International Journal of Material and Mechanical Engineering (IJMME) Volume 2 Issue 4, November 2013

Dr Raghupatruni Bhima Rao is School of Mines, Dhanbad. He has visited Lulea University working as a Principal at Aryan Institute of Technology, Lulea, Sweden, as a Guest Researcher. He has of Engineering and Technology, a few patents and more than 200 publications in Bhubaneswar, India. He also worked as international and national journals and proceeding volumes.

Chief Scientist at CSIR, Institute of He has received many best paper awards and recognitions Minerals and Materials Technology, especially in the area of additives in grinding. The National Bhubaneswar, India, after completing Mineral Award in the area of mineral beneficiation is one of his double post‐graduation from Andhra University. He his prestigious recognitions. obtained Doctorate in Mineral Engineering from the Indian

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