A Report

On

Industrial Training In Mechanical Maintenance And Introduction OfHindustan Zinc LimitedRajpura Dariba Mines

(1st june, 2013 to 15thJuly, 2013)

Submitted By

Garvit Agrawal(11001894)B.Tech Mechanical Engineering (2010-14)

Lovely Professional University, Punjab

Under the Guidance ofMr N.K.DevpuraMr J.P.VermaMr R. L. SainiMr Y. S. Bhati

Hindustan Zinc Limited, Rajpura Dariba Mines

CERTIFICATE OF COMPLETION

This is to certify that Mr. Garvit Agrawal,fourth year student of B.Tech Mechanical Engineering from Lovely Professional University has completed the project titled Industrial Training in Mechanical Maintenance and Introduction of Hindustan Zinc Limited, R.D.Mines during the period from 1st June 2013 to 15thJuly 2013 at Hindustan Zinc Limited, Rajpura Dariba Mines.

Mr N.K.Devpura(Sr. Manager, Safety & Training)

ACKNOWLEDGEMENT

First and foremost, I am highly indebted to the Hindustan Zinc Limited, R.D.Mines, for providing me an opportunity to carry out the project work under their highly skilled and experienced team. Moreover, the learning atmosphere present over here enhanced my interest in the project.

I would like to express my special thanks of gratitude to my mentors Mr. J.P.Verma, Mr. Ramji Lal Saini,Mr. Yogendra Singh Bhati, who were always there with me throughout the project despite their busy schedule. They helped me with everything they had, be it their approach towards the project, their practical knowledge and experience which made me analyze things in a better way.

I would also like to acknowledge the assistance of the following individuals, without whose help, successful completion of my project would not have been possible: Mr. Sunil, Mr. Prabhu Verma, and Mr. Babu Singh Ravna.Thanks are also extended to those who acted as a reference group, and to others who willingly contributed.

TABLE OF CONTENTS

1. Objective and Methodology.....12. Introduction.......22.1 Exploration History.......32.2 Regional Geology and Structure.......32.3 Aim of an industry........42.4 Problems/interruption with an indust...42.5 Uses of Zinc......53. Mineralisation...63.1 Mine Geology.......63.2 Lithology..63.3 Geological Discontinuous .......73.4 Lodes and Mineralization.............73.5 Reserves.......74. Mining...........84.1 Access to the mine...84.2 Fill Plant..94.3 Rock Mechanics Cell...95. Environment Management...106. Vocational and Safety aspects...107. Infrastructure Facility.......117.1 About Organisation........127.2 Central Workshop..127.3 Mining Department207.4 Mill Mechanical Department.308. Mining Process439. Overview of the Process.4510. Conclusion...46

OBJECTIVE & METHODOLOGY

OBJECTIVE

The objective of this training is to get practical and field knowledge of the mechanical engineering. To get in depth knowledge and role of the different departments such as workshop, mill, mining and to know how mining is done.

METHODOLOGY

The training started with the importance of the safety aspects and what are the safety measures taken in the industry. Further, the equipment required and how the mining is done and what are the parameters for designing the cement slurry that is required during mining. The training also focused on how to refine and separate the different elements from the ore that was taken out by the mining process.Also involved, the different machines used at different departments such as workshop, mill, mining. The training included how to refine and separate the elements from the extracted minerals.

1. INTRODUCTION

There are many places in our country, where we get different types ofmetallic substances as raw material for industries. In these substances, the metals are present in compound form. These substances are called as minerals. Minerals are mostly present as oxides, sulphides, carbonates, chlorides and silicates. Those minerals from which we can get the metals conveniently and at low cost are called ores.Less reactive metals, as gold, silver, platinum etc. are obtained in Free State in nature. Copper is basically obtained as copper pyrites (CuFeS2). It is obtained from mainly the states Rajasthan, Bihar, Madhya Pradesh, Orissa, Karnataka etc. Iron is obtained from Hametite (Fe2O3), from the states Madhya Pradesh, Andhra Pradesh, Tamil Nadu, Karnataka, Goa, and Maharashtra. Zinc is mainly obtained from its ore Zinc Blende (ZnS) available mainly in the states Rajasthan and Orissa.

Rajpura Dariba Mine is located at the southern extremity of Rajpura Dariba Bethumni metallogenic belt in Rajsamand district, Rajasthan, at a distance of 76 kms from Udaipur. Other prominent deposits in the belt are Sindesar Khurd and Bamnia Kalan. Rajpura Dariba has been under production since 1983 whereas Sindesar Khurd is currently under mine development stage.

Extensively mining both by opencast and underground methods was carried out by ancient miners for many centuries. Carbon dating of wooden implements recovered from the ancient working has these operation are as old as 2500 years. Surface manifestation of mineralization is by the way of an extremely well developed Gossan (declared as an National Gossan Monument by GSI).The zone of oxidation extends to depth of 40-50m from surface. The presence of ancient workings, heaps of mine debris and slag serve as guides to Sulphide Mineralization.

1.1.1 EXPLORATION HISTORYThough worked extensively in the past, well-developed gossan / ferruginous breccia and slagheaps were first reported by B.C. Gupta of Geological Survey of India (GSI) in the year of 1934. However, systematic exploration was initiated by GSI in 1962 at the southern end of belt.Drilling in Rajpura Dariba, Bethumni and few other locations were completed by 1970. This was followed by detailed delineation, feasibility study and commencement of mining at Rajpura Dariba deposits by Hindustan Zinc Limited (HZL).

1.1.2 REGIONAL GEOLOGY AND STRUCTUREDariba, Bethumni Metallogenic belt comprises an assemblage of medium to grade metamorphic equivalents of orthoquartzites carbonates and carbonaceous facies rocks belonging to Bhilwara Super-Group (3.5-2.5 Ga) and extends for about 19 km in north-south direction. This cover sequence is underlain by basement rocks (gneisses and schists) of Mangalwar Complex.The structure of the belt is as an isoclinal fold (GSI, 1990) having synformal closure at Dariba in south and antiformal closure at Bethumni in the north.

The synformal closure exhibits steep plunge (55- 60) towards ENE and the antiformal closure shows shallow plunge (15- 20) towards NE.

The regional trend of the formations veers from N-S between Dariba and Rajpura in the south, to N15E-S15W between Sindesar Khurd and Sindesar Kalan in the middle and finally to N50E-S50W around Bethumni in the north. The rocks generally show moderate to sleep deep towards E\SE.

1.1.3 Aims of an industry To produce goods To have continuous production To produce goods at low cost To produce goods of high quality Have long life of equipment.

1.1.4 Problems/interruption with an industry Break Down Power Failure Industrial relation problem Fire and Explosives.1.1.5 Uses of Zinc Zinc Powder Bras Items GI pipes CuSO4

2.1 MINERALIZATIONLead zinc deposits of various sizes and grades occur throughout the belt in both calc-silicate bearingdolomite and graphite mica schist horizons. The latter in general containing low grade disseminated Sulphides of large volumes. The resources of the belt is around 261MT grading 3-4%Pb+Zn. However, the reserves with higher grade constitute only 37MT with 2.2% Pb and 7.3% Zn confined to Dariba, Sindesar Khurd and Bamnia kalan.

Ore mineralogy of the belt, particularly at the south end, is unique due to its multi-metallic sulphosalt association. Sphalerite and galena mineralization exhibits lithological, stratigraphic and structural control and occurs in the form of fracture filling, veins, stringers and disseminations forming tabular to lenticular bodies, Rhythmic banding is characteristics of mineralization in graphite mica schist.The nature of mineralization is synsedimentary, later remobilized and recrystallized during subsequent polyphase deformation and metamorphism.

2.1.1 MINE GEOLOGYDariba mine is located at the southern extremity of the belt. The ore materials are designated at main lode (south and north) and east lode. Mining activities are, at present, restricted to main lode only.

2.1.2 LITHOLOGYThe mine area is constituted mainly by a sequence of meta-sedimentaries consisting of mica schist, calcareous biotite schist and graphite mica schist (from footwall to hanging wall).

Calc-silicate bearing dolomite occurs within the graphite mica schist horizon towards its contact with the calcareous biotite schist. The formations, in general, strike N-S with moderate to steep easterly dips. Cross-beds and laminations are observed in mineralized schist and dolomite bands. The area between the South and North lodes is traversed by 2-10m wide meta-basic dykes.

2.1.3 GEOLOGICAL DISCONTINUITIES

Four sets of joints developed due to deformation.

Shears are represented by narrow zones of crushing, beneficiation and gouging, mostly 0.1-2.0m wide. These are highly persistent along strike and dip and occur at the contacts and within the ore bodies.

Faults are of reverse type with low south-easterly dipping planes striking N40- 60E.

2.1.4 LODES AND MINERALIZATION

The main lode extends over a strike length of 1700m and is separated by a barren stretch of 3000m into two ore bodies viz. South and North lodes. The South lode, striking N-S and dipping 60-70 towards east, has a strike length of 500m. The North lode has a strike length of 900m. It strikes N-S and dips 70-75 towards east. The East lode, with a length of 600m, also strikes N-S and dips easterly at 60-70. It is located about 150-200m away from the hangwall side of the South lode. The average widths of South, North and East lodes are about 24m, 18m, 18m respectively and to decrease in depth.

Ore forming minerals are mainly sphalerite, galena, chalcopyrite and fahlore (tetrahedrite-tennantite).Preferred concentration of silver has taken place in fahlore and chalcopyrite.

2.1.5 RESERVESThe main lode ore resources are estimated to be about 17.76 million tonnes grading 2.0% lead, 7.6% zinc, and 90-100gm\t of silver.

The East lode has a potential of 6 million tonnes with 1.3% lead and 6.9% zinc2.2 MINING Underground exploratory mine development was started by GSI in July, 1967 through two incline shafts, located 100m apart on the Western side of Dariba Hill, to open levels at 436 and 400mRL respectively.

Subsequently, HZL acquired mining lease of 11.42 Sq. km covering Dariba and parts of Rajpura block in April, 1970.

Mine was re-opened by HZL on December 28, 1971 and deepening of one of the inclines upto 300MRL was taken up for underground exploration and mine development works.

2.2.1 ACCESS TO THE MINE Access to the mine is through a main and an auxiliary shaft.

The main shaft is 592m deep from the surface (500mRL) to (-) 92mRL. It is equipped with tower mounted keeps winder for skip (740kw) and cage winding (236kw).

The skip winder is equipped with two counter balanced 6t capacity skips and raises ore from underground.

On the other hand, the auxiliary shaft extends down to 0mRL and is used for material winding only besides serving as a second outlet. It is provided with a 225kw drum winder, which can hoist 3.5t of load at a time. 50m spaced main levels have been opened between 400 and 0mRL, and each level is connected to both the shafts.

A computerized process control system along with an automated grinding circuit control, In-stream analysis (ISA) and instrumentation for other parameters is in use for improving metallurgical efficiency.

Multi-gravity separators (MGS) for removal of graphite in lead concentrate and column flotation for controlling silica in zinc concentrate have been installed.

2.2.3 FILL PLANT A fill plant is in operation fill to the mine. Classified mill tailings from a fill storage tank is conveyed to a mixing tank where it is mixed with cement at a desired rate through RV feeder and a conveyor belt as per demand from the mine.

The cement mixed slurry is pumped to underground through centrifugal pumps for filling into void spaces.

The quality parameters of the fill materials like grain size, pulp density and cement proportion are constantly monitored through proper instrumentation.

2.2.4 ROCK MECHANICS CELL This Department works for safety of employees working in the underground mining. This Dept. deals with:

Vibration testing: for this, vibration meter is used to measure vibration produced due to explosion in underground mining. It is max. up to 15mm\sec. It can be controlled by reducing the amount of explosives used to carry out explosion.

Stress testing: for this, stress meter is used to find out tensile strength of rock bolts which are used to provide support to rocks. It can support wt. max upto 8 tonnes but used to support only 1 tone in mining.

Measurement of flow rate: flow rate of water is measured through cement filling in void spaces to check the strengthening of cement. It should be upto 10cm\hr. More fine is the grain size, less the water flow. Hence grains of -400 mesh size should not be more than 20%.

Displacement measurement:To determine displacement of rocks under given depth, HOOK JOINT method is used.

Rock testing: Testing of compressive strength of sample of rock under given depth is carried out on universal testing machine (UTM).

2.3 ENVIRONMENT MANAGEMENTAn Environment Management Plan has been prepared which covers monitoring of the environment on regular basis and also deals with the input required to improve it.

The various parameters of environment which are constantly monitored are Water and waste water, Air Noise Soil Dispersal of metal in vegetation Flora and fauna. In addition, a planned scheme has been launched for afforestation in and around the mine area.

2.4 VOCATIONAL AND SAFETY ASPECTS A Vocational Training Centre educates the work force on various vocational and safety aspects related to the profession.

Periodical Refresher Courses are also conducted for the workers to apprise them of the latest safety aspects with a view to handle the equipment with safety.

Accidents is most unwanted interruption because it involves human life and the main effects of accidents are Stopping of production Human suffering Loss of good skilled employees Material loss Demoralizing effect on employees and society Legal proceeding Harassment to management Compensation

Safety Materials:Safety Belt,Safety Shoes, Ear Muff, Face Shield, Helmet, Ear Plug, Safety Glass, Breathing Set, Acid proof glass, Air stream helmet, Dust and gas mask.

2.5 INFRASTRUCTURE FACILITYRajpura Dariba Mine has all the infrastructure facilities including a Central Workshop for any major overhauling, maintenance and fabrication job.

The power supply to the mine is received from Rajasthan State Electricity Board. Two 3.5MW DG sets have been installed at the mine as standby.

Water requirement for industrial and township usage is met from Matrikundia dam built on Banas River about 22km away. HZL also has a few tube wells in Banas River near Bamnia Kalan for augmenting water supplies from Matrikundia.

A Workforce of 704 Workmen is employed to support various operations of the mine. The strength of Executives is 94.The mine has a well-laid township having marketing, recreational and cultural facilities.

A 30 bed hospital fully furnished with modern therapeutics equipment manned by specialized staff attends to the medical requirement of the employees and their families.

2.5.1 ABOUT ORGANIZATION

Sterlite Industries India Ltd. (SIIL), a part of Vedanta Group is one of major player in non-ferrous metal industry. SIIL in turn controls Bharat Aluminium Company (BALCO) and Hindustan Zinc Ltd. (HZL). The Indian promoters Chennai Aluminium Company (MALCO) currently holds 7.13% in SIIL.

Vedanta is a London listed metals and mining company with its principal operation located throughout India.

The major metals produced are Aluminium, copper, zinc and lead.The company also manufacture aluminium cold rolled products with technical know-how from J W aluminium, US. During 1994, it entered into the manufacture of optical fibres, the basic raw material for optical fibre cables.

This project was promoted through Sterlite Communication (SCL), a subsidiary, in technical collaboration with the Nokia group, Finland leaders in the telecommunication sector.

2.5.2 CENTRAL WORKSHOPNEED:

This workshop is responsible to maintain all the mechanical equipment of the plant. Any damaged from any department is brought to this workshop and after required repairing will be sending back to the concerned department for further use.

SUB-DEPARTMENT:

HEMM: Heavy Earth Moving MachineS.NName of AssetsDescriptionName of Company

1.Lathe machine Model 1675Height 200mmSpindle bore 55mmM\s Mysore Kirloskar Ltd., Hubli

2.Lathe machine Model LB 17Height 170mmSpindle bore 90mmM\s Chamundi Machine Tools Ltd., Banglore

3. Lathe machine Model LB 20M\s HMT

4.Lathe machine Model EP 2215 Spindle bore 90mmM\s Mysore Kirloskar Ltd., Hubli

5.Shaper machine Model WE 0366M\s Modgil Comp., Batala

6.Radial drill machineModel UVR-5M\s Batiboi and co., Surat

7.Power-hacksaw machine Model heavy dutyM\s Machinery Impex, Mumbai.

8.Hydraulic press200 tonesM\s Advance Automation and Process Control Pvt. Ltd.

9.Plate-bending machineModel PINCTM\s Citizen Engg. Works, Mumbai

10.Horizontal-boring m\c Size 100mmM\s Kamala Foundary, Batala

11.Compressor Model VT 250 P.DM\s Atlas Foundary, Batala

12.Crane Model Double girderM\s Dhiraj Enterprises Ghaziabad

SPECIFICATION OF THE MACHINE TOOL:1. Central Lathe LB 17ManufacturerHindustan machine tool

ModelLB 17

Height of centre170mm

Type of the bedStraight bed

Spindle speed18

Range(standard)45-1000

(slow)23-1000rpm

Spindle noseAmerican standard

Spindle bore42mm

Motor(standard speed)7.5\3000kw\rpm

(slow speed)5.67\1500Kw\rpm

LubricantsMobile Oil DTE Heavy ormedium Mobil Grease BRB No.1

2. Centre Lathe LB 20

ManufacturerHindustan machine tool

ModelLB 20

Height of centre200mm

Type of the bedStraight bed

Spindle speed18

Range(standard)32 to 1600 RPM

(slow)16 to 800 RPM

Spindle noseAmerican Standard L1-Type

Spindle bore42 mm

Motor(standard speed)7.5/3000 KW/RPM

(slow speed)5.6/1500 KW/RPM

LubricantsMobile Oil DTE Heavy ormedium Mobil Grease BRB No.1

3. Enterprise 1675 High speed Precision LatheManufactureMysore Kirloskar Limited

Centre Height200 mm

Swing over Bed400 mm

Swing over Cross Slide245 mm

Spindle NoiseCam lock D 1-6or 2-6

Spindle Bore 55

Motor of Motor7.5 HP

Speed630 to 800 RPM

4. Enterprise 2215 High Speed Precision LatheManufactureMysore Kirloskar Limited

Centre Height280 mm

Swing over Bed560 mm

Swing over Cross Slide375 mm

Spindle NoiseCam lock 11

Spindle Bore1.5/1500 KW/RPM

Capacity of Motor15 HP

5. Knee Type Milling MachineManufactureHindustan Machine Tools Limited

ModelFN 2

No. of Spindle Speeds18

Speed Range355-1800

No. of Feeds18

Power of Main Motors5.5/1500 KW/RPM

Feed Motors1.5/1500 KW/RPM

Weight3300 KG

LubricantsMobile DTE Oil, Mobile Grease No.2

CoolantSOLVAC 1535 or Indent Cutting Oil

Swivel of Table on either side45

Swivel of Milling Head oneither side45

6. Punching, Shearing, Cropping Machine:ManufactureAshok Manufacturing Co. Pvt. Ltd.,New Delhi

ModelPBSCN-13

This machine serves as three machines in one, it have different units They are:Punching UnitPlate13 mm

Flate125*16 sq. mm

Length of Blade250 mm

Round Bars41 mm

Square Bars38 mm

Plate Shear & Bar CropperPlate13 mm

Flate125*16 sq. mm

Length of Blade250 mm

Round Bars41 mm

Square Bars38 mm

Section Copper UnitAngle Squarer110*1000*111 cu mm

Notcher Weight square ToolsPlate10 mm

Notching Width50 mm

Notching depth on stroke65 mm

No. of strokes/min36 mm

Motor Power5 HP

Net Weight of Machine3 TPmmes

LubricantsTELLUS 29 BURMAH SHELLO,Shell Nareta 3.

2.5.3 MINING DEPARTMENTNEED:The need of mining is to take ore from earth by process like drilling, blasting, mucking and crushing.The need of a mechanical engineer is in maintenance the various machines in used in the process that done the process of taking ore from underground.

Vision:

Fitness of machine:

For this regular checking of various machines is necessary which include:a) Proper lubricationb) Proper maintenance for regular working.

Service:In this monitoring of condition of machine is done atregular interval of time.

Repair:In this damaged parts are either replaced by new parts or repaired so that machine works properly.

List of Major Equipment& Machineries of Mining BlockmRL: Meter Reducing LevelLevel nameMachines observed

250 mRL1. CUBEX R1102. LHD 10A3. SIMBA M\C

300 mRL1. TORO LH2032. DIESEL LOCO

100 mRL1. WAGNOR2. CUBEX R1103. SIMBA M\C

-35 mRL1. Crusher

-55 mRL1. Conveyor\Belt

50 mRL1. LHD

Other levels are 200,150 and -92 mRL.100 mRL# Distance from North to South: 1900m1) Wagnor machineMachine typeLoader

Weight17 tone

Bucket capacityApprox. 5 tone

Motor capacity100 BHP

Tyre size (Tubeless)17.5x 25

Tyre pressure65-70

Speed gears03

Hydraulic tank capacity273 litre

PumpTandon pump

Pump flow capacity64 GPM

Power supplied440 volts

Hydraulic fluidFluid-32

BOBCAT Machine It is also a loader type machine used to displace the other machines like simba machine, pump sets, motors etc. to the required place. Its output power is 36.4kw. It is a diesel operated loco operated by single operator. It is also provided with a bucket to carry load.300 mRL1) TORO LH 203Company nameSandvick mining and const.

Machine typeLoader

Engine power71.5 CC

FuelDiesel

Total wt.8200 kg

Tyre size12x20

Tyre pressure (front)87

(Rear)67

Bucket capacity1.51 cube tone

Tank capacity122 litre

Torque converter capacity22.5 litre

OilNo.30

Functions: Loading Hauling Dumping0 mRL# North- South distance: 914mName of loco1.Clayton2.Gemco

TypeElectric loader

Company nameClarke company ltd.,England.

Power supplied250 volts

Motor capacity45 BHP

Wagon capacity5 tones

No. of wagons10

No. of motors02

Function of loco:Electric-operated loco are also called as Tram. Tram has the function of loading the wagons from the suits where ore is received from different levels and then carry it on the ramp.At the dumping point, ore is dumped into the main hole; transfer the ore to -35mRL for crushing operation.

250 mRLSIMBA Machine:

It is simply a drilling machine used to make holes of 57mm diameter and 6m depth in the roof of the level. PVC pipe along with cable bolts are then fitted into the hole. Cement slurry is then injected into the pipe with pressure by injector. Cable bolts are used to support the surface of adjacent upper level.PARTS OF SIMBA MACHINE:SkidRingMotorFeed beamJack column bar

Levers to control Air and Water supply

Drilling tool having chuck and valve

Screw bar with lead screw

Water along with compressed air of 92-110 PSI is used to carry out operation.

TORO-151 Loader

Noise level(at 2300rpm)93 DB

Total length6970mm

Width without bucket1420mm

Maximum width1480mm

Height with safety canopy1740mm

Operating weight8700kg

Total loaded weight12200kg

Bucket capacity1,5m

Bucket motion time(raise)(lower)5.5sec2.9sec

Driving speed (Ist gear)(IInd gear)(IIIrd gear)5km\hr3.3km\hr24km\hr

Frame materialRaex multisteel

No. of cylinder06

Cooling systemAir cooled

Combustion systemDirect injection,4-stroke

Exhaust systemDouble wall exhaust pipe

Turning angle40

Tyre size12x20

Fuel tank capacity130litre

Tyre pressure (front)(Rear)87.1psi50.8psi

250 mRLCUBEX R-110Function: This is used to drill a hole of 165mm diameter and depth of 50m in the underground mining surface so that operator can fill up explosives in it for blasting.It has two basic parts: 1. Compressor 2. Drilling machineCUBEX CompressorPressure of compressed air received from1. Surface compressor2. CUBEX R-110 compressor92-110psi300psi

Thus, function of compressor is to compress the air received from surface compressor.

PATH OF COMPRESSED AIR IN CUBEX COMPRESSOR:Primary filter ---- Secondary filter ---- Valve Suction ---- Inlet manifold ---- Compressor ---- Discharge manifold ---- After Cooler ---- Thermostat Valve ---- Air receiver ---- Transmission

Primary filter: It is used to remove dust particle, moisture etc. having size upto 12 from compressed air.

Secondary filter:Remove dust particle, moisture having size upto 5.

Valve:It is operated automatically by joystick, to control the amount of compressed air to pass.

Suction inlet manifold: It is attached with three piston-cylinder assembly to compress the air. These are operated independently to control the magnitude of pressure of compressed air.

After Cooler: Compressed air received is at high pressure and temp. (Boyles law), so to lower down the temp it is passed through after cooler having tiny fins on surface.

Thermostat valve: To further lower the temp. air is passed through thermostat valve having two sections: one for compressed air and other for cold water. Water absorbs heat from air and then drained off.

Motor capacity75 BHP

Receiver tank capacity550psi

Price2cr 30lks

DRILLING Machine of CUBEX R-110Machine typeDriller

Hydraulic pump capacity71CC

Diesel pump capacity85CC

Hydraulic fluidFluid-32

Length of feed rod1.5m

-35 mRLCRUSHER:TypeDouble Toggle Jaw Crusher

CompanyUTMAL

Size1200x900m

Power supplied160 KW

Capacity250 TPH

Discharge size6

FeedRose Chain Feeder

The blasted ore cannot be taken as it is to the surface because lumps are large in size and heavy to carry. So before taking it to the surface, the ore should be crushed in DTJ crusher. Lumps of ore from each level are dumped into the main hole at 0 mRL transferring it to the crusher where it is crushed down into lumps size of 6. Skip from -55mRL carry the crushed ore on the surface for further processing.

-55 mRLBelt\Conveyor: Total length: 150m Motor capacity: 20HP Belt material: Linol Load carried by skip: 6tone Rock material after crushing into small lumps is passed over the vibrator, which transfer it on the conveyor.

Belt at it other end dump the lumps into the container having load cell and diverter. As the wt. of ore equals to 6tonne, load cell get activated and these are dumped into the skip which carry it on the surface.

There are two skips; skip A and B.

Diverter controls the process of loading of ore into the skip alternatively.

2.5.4 MILL MECHANICAL DEPARTMENTNEED: The ore extracted from mine are in form of large lumps with high percentage of impurities. Hence ore cannot be taken to smelting plant as it is. So the process of ore dressing is carrying out at mill dept.

Mill block has been divided into following section:

1. CRUSHER

This Dept. works to fulfil the requirement of ball mill. Lumps having size in the range of 250-150 mm are crushed down to 16mm or less. One sec. and two tertiary crusher work to crush lumps of large size.

Crusher AssemblyFollowing are the parts of crushers installed:

CONVEYORS:

Conveyor\belt is used to carry ore in bulk from one place to other where ore is required. These conveyors are installed horizontally and somewhere in inclined manner. It moves on rollers with the help of pulleys which are driven by motors. Snub pulley is also installed to increase the contact area of belt on pulley to prevent slipping. Conveyors are made of rubber plies and fasteners are used to join two conveyors.

Conveyor no.Width sizeMotor power

1085800mm45KW

1325

1340

12201200mm110KW

12701000mm70KW

Reciprocating Plate FeederCompanySISCO

Size1526x760mm

Capacity20-200TPH

Power5HP

Stroke30-175mm

Stroke\min32

Weight1840kg

Sun Iron & Steel Co.(P)Ltd.

Function: Feeder is used to transfer heap of lumps on the conveyor by the reciprocating motion of plate on the wheels driven by the motor and chain on sprocket.

CrusherType CapacityMotor FeedDischargeCrusher No.Feeder No.

Standard Head Cone Crusher(HEC)350TPH160KW150mm50mm12151095

Short Hand Cone Crusher(SYMON)300 TPH184KW50mm16mm1296,12951286,1285

The ore from mining is feed to crusher where it is crushed to desired size, that crushed ore is then subjected to screens which have very fast vibrating motion, the screened ore is collected in the tank and remaining ore is again feed to SYMON crusher by conveyor1270.

Scalping Screen This is also called Double Deck Screen. Both the screens are large metal grid of size 20x8 with square holes in it to allow ore particle. It is inclined at 20. The upper grid of 25mm holes to pass through for bottom screen of holes size 16mm. The ore particles of size bigger than specified above are feed back to the crusher through conveyor 1270.

2. Ball Mill

Need:This is required for crushing the ore of 16mm size into (-) 400 mesh size to carry out froth flotation process.

Balls of Ball MillBall Mill FeedMotor capacity7.5KW

Gear boxElecon

Reduction ratio60:1

Gear box type7FSS

Belt materialNylon

Width600mm

Length51.3m

Capacity63TPH

No. of plies05

PulleyDrum dia x width

Head pulley400 x 880

Snub pulley210 x 675

BALL MILLCompanyKCC, Madras

Size(Diameter x Length)3.3 x 4.5m2.7 x 3.7m

Capacity900 TPD

Rotational speed (rpm)18

Bearing typeDouble row spherical roller

Gear box

CompanyElecon

Reduction ratio10:1

TypeSBN-500

No. of teeth on girth gear228

No. of teeth on pinion gear26\27

Grinding media size2,3,4

There are four ball mills for crushing of ore. Three are of dia. 3.3 and one is of 2.7. The ore size of 16mm is supplied to ball mill through conveyor belt. For proper crushing of ore, rotational speed of ball mill should always be less then critical speed otherwise grinding media will keep on rotating along with ball mill results in improper crushing of ore.

Power transmission to Ball MillMotor ---- Fluid Flywheel ---- Gear Box ---- Pinion Gear ---- Girth Gear ---- Ball Mill

These Ball Mills are cylindrical in shape having layer of manganese steel as a liner to prevent the wear and tear of mother body during the crushing of ore.

About 12 tonnes of manganese steel balls (Grinding Media) are used in each Ball Mill to grind the ore into fine particle of (-) 400 mesh size.

InstrumentsLoad Cell:It is mounted near the end of conveyor belt to measure total feed (ore) to the ball mill. It measures feed in tonnes. It converts the measured value into electric signals representing the output to the operator.

To Measure Level in Sump:

UV radiations are used to measure level of slurry in sump. UV radiations after reflecting back from the bottom of sump is received by radiation meter and measures time required by the radiations to travel total distance. Motor used to pump slurry is also frequency based and adjusted according to level of slurry in the sump.

3. FLOTATION CELL

Ore slurry from ball mill is mixed with chemicals like MIBC, Copper Sulphate in definite proportion to extract the concentrate of Lead and Zinc from slurry. The flotation cell is an assembly of tank and a rotor fitted in series. There are basically two cell blocks: AS2-6, AS2-3

Flotation CellSpecificationAS2-6AS2-3

Volume (in m)63

No. of motors0201

Motor capacity11KW11KW

Impeller diameter400mm400mm

Process Description Ore slurry from Ball mill is carried to conditioner from where it is distributed equally to four cell blocks. Slurry is mixed with definite proportion of MIBC and CuSO4. Here, MIBC act as a Froather and copper sulphate along with cyanide settle down zinc present in slurry. Impeller near the bottom of tank rotates the slurry and the air from bottom blow concentrate to top of tank called filtration. Froths are separated and passes into lead filtration block. Remaining slurry is mixed with ZnSO4 and froths so obtained are separated passing into zinc filtration block.

FILTRATION

In this section water is removed from the ore using two filters:

1. Drum Filter 2. Pressure Filter

Drum FilterIn drum filter, there is a cylindrical drum which rotates so that slurry is uniform in composition. One end of the drum is attached with vacuum pump so that moisture is absorbed from the slurry by applying pressure of 500 mm Hg. The outer part of drum is made of cloth having high porosity.Drum is 8 feet in dia. and 10 feet in length.

Pressure filterIn this filter, water is drained from slurry by applying high pressure. It is made in Germany and controlled automatically by computer. Process of pressing is completed in 8 minutes and about one tonne of concentrate lead\zinc is produced.

THICKENERSThickener where excess water is recovered for recycling in plant and underflow is pumped to Tailing Dam constructed 4 kms.

VASA PUMPThese pumps are suitable for: Mining and Mineral processing Cyclone feed Industrial processing Mill discharge Medium duty abrasive slurriesBenefits: Robust construction designed for highly abrasive, maximum duty. Maintenance slide base option. Computer aided designed thick volute casing and heavy duty large diameter impellers, carefully matched to provide high efficiency, hydraulics for even wear.These pumps operate at or near their highest efficiency. Thereby reducing both the rate of wear and power consumed.

Impeller

Vasa Pump

Roller Bearing

TAILING DISPOSAL & FILL PLANTSlurry after separation of concentrates is pumped to Fill plant where Hydro cyclone separate slime (-) 37 and sand.

Slimes are pumped to Tailing Thickenerwhere excess wateris recovered for recycling in plant and underflow is pumped to Tailing Dam constructed 4 kms. away from mine.

Three pumps are connected in series to pump underflow to tailing dam.

In the mines for filling stops, + 32 microns fraction of tailing is used as fill material. River sand is used to supplement the fill as and when required.

Cement is added for the initial two lifts of the operations. The fill material (pulp) is pumped at 65% solid through 10 mm dia pipelines which pass from surface to underground through bore-holes. For this, two pumps are connected in series.

Design capacity of the supply of fill is 50 60 tonnes per hour through each of the three lines.Out of total tailings 55% is used for mine back filling and balance 45% is pumped to tailing dam. Solids are allowed to settle in Tailing Dam and water reclaimed through filter and recycled for plant use.

For VRM operations the Fill Plant has been modified with arrangement for automatic handling and addition of cement in the desired quantity. Monitoring of various quality control parameters such as particle size analysis, pulp density, cement ratio of10% and 5% being maintained depending on filling for plug formation. The average monthly requirement of cement in VRM back filling is approximately 700 1000 tonnes.

2.6 MINING PROCESS

1. Ore Detection First process that comes in mining is ore detection. It is done by taking sample of ore to the laboratory where percentage of Zinc and Lead are find out with various chemical methods.

2. DrillingDrilling process is carried out in underground mining for:

A hole of 165mm dia. and 50m depth has to drill in under-ground mining surface so that an operator can fill explosives in it for blasting. A hole of 57mm dia. and 6m depth has to drill in the roof of the level. PVC pipes along with cable bolts are then fitted into the holes so as to support surface of adjacent upper level.Following are the machines used to carry out operation: CUBEX R-110 SIMBA machine M.T.I

3. Blasting In blasting, explosives are filled in holes of 165mm dia to obtain ore rich in percentage of Zinc and Lead. All workers come at surface from underground during the blasting because loose can fall after explosion causing the severe accidents.

4. Mucking After blasting, ore so obtained is in form of large lumps. This blasted ore is taken to the place where it is collected in huge amount and then it is subjected to hauling machine. Thus, the process of taking ore to hauling machine is called Mucking. This process is done with Wagner and Toro which are operated either manually or automatically.

5. Hauling Hauling is the process of taking ore from suits of each level and dumping it into the main hole, subjected that ore to the crusher. Hauling process is carried out at 0mRL using the Loco which are:Electric LocomotiveDiesel Locomotive

6. WINDERSIt has two sections: Cage and Skip

Cage Cage is a type of lift used to carry workers to the various levels ranging from 200mRL to (-) 92mRL. Its maximum capacity is 6 tones and can carry 40 workers at a time. Its maxspeed is 10m\sec but for safety it is operated at 3m\sec.

SkipIt is used to carry crushed ore from underground i.e. (-) 55mRL to the surface. There are two skips; Skip A and B connecting to the winder. Both skips run simultaneously so that they balance each other. Its max capacity is 6 tonnes. Its max speed is 10m\sec3.1 OVERVIEW OF THE PROCESS

MiningScreen HouseMBall MillChemical Process Zinc ThicknerTailingThicknerBulkThicknerLead ThicknerCrusherPlantM

3.2 RESULT

The result of the training was to get the indepth knowledge about the machines used in industries and how to communicate and handle the workers in a team.The maintenance work gives idea about the different parts used in machines and how to handle a machine or any work during its failure.by this training I get knowledge about the mining processes ,different machines used during mining and their maintenance .then further in mill plant I get to know the crusher plant and ball mill process in detail and replaces the liners of the ball mill and the crusher. This training really help me during my job career in future and provide help to me in developing my professional future.

4.1 CONCLUSION

It was a wonderful learning experience at Hindustan Zinc Limited,R.D.Mines site for one and half month.i gained a lot of insight regarding almost every aspect of site like in mining ,mill and workshops .i was given exposure in almost all the departments at the site.The friendly welcome from all the employees is appreciating,sharing their experience and giving their peace of wisdom which they have gained in long journey of work.I am very much thankful for the wonderful teaching facility from HZL.I hope this experience will surely help me in my future and also in shaping my career.

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