Utilisation of Waste Derived out of Mining

1
Utilisation of Waste Derived out of Mining

• V.D. Rajagopal, M.Sc., B.L.,
• Director of Mines Geology, Govt. of Andhra
  Pradesh
  Vice-Chairman Managing
  Director,
• Andhra Pradesh Mineral Development Corporation
  Ltd.,
• (A Government of AP undertaking)
• Hyderabad

2
A.P. at a Glance on various Mineral Revenue Share
(Revenue in Crores)
3
Comparative Statement with Other States Mineral
Revenue Collections
4
Introduction

• Exploitation of mineral resources creates huge
  waste/sub grade material dumps
• A waste is a waste as long as it is unused
• Waste dumps all along the mining belt for
  various minerals reveal necessity of attention
  to be paid for its utility for prosperity of
  human kind by way of creation of large scale
  employment in rural areas
• This would form as best environmental mining
  planning practice.

5
Case studies

• Dimensional Stones
• Barytes
• Clay
• Asbestos
• Dolomite
• Slate
• Tailings derived out of gold mining
• Sand Stone out of waste derived from M/S. S.C.C.
  Ltd.

6
Dimensional Stones

• Andhra Pradesh is one of the important Granite
  producing states
• unique varieties are
• Galaxy granite deposit of Chimakurthy in Prakasam
  district
• Jet black granite of Warangal and Khammam
  districts
• G20 variety of black granite from chittore
  district.
• Blue and White variety of Srikakulam district
• Tan brown variety of Karimnagar district
• Sierra grey of Anantapur dist
• Kuppam green.

7
Recovery of Granite blocks

• Black Granite 10
• Colour Granite 40
• Presently producing sizes
• Gang saw size (270 cm x 150 cm and above)
• Block cutter size (below 270 cm x150 cm)
• Small sizes (70 cm x 35 cm x 35 cm).

8
Recovery of Granite blocks contd..

• The rest of the material is thrown as waste
• Waste granite can produce useful slabs, which
  ultimately serve on par with granite of bigger
  sizes.
• Recovery of small size granite blocks ranging
  from 15 centimeters to 35 centimeter is possible
• As masonry technique is superior in India,
  Flooring can be laid without any surface
  variations and, if colour combinations are used
  flooring can be of different designs.

9
Recovery of Granite blocks contd..
10
Interesting statistics of value of waste Granite
The situation is more or less similar in other
granite producing states
11
Limestone Slabs

• Flaggy limestone deposits occurring throughout
  the State of Andhra Pradesh in
• Kadapa basin
• Palnadu basin
• Bheema basin
• Mining of flaggy lime stones for the last several
  years produced huge waste dumps in Anantapur,
  Kadapa, Kurnool, Guntur, Nalgonda and RR
  districts.

12
Limestone Slabs contd..

• Flaggy limestone mainly constitutes
• Calcium Carbonate ranging between 36 and 50
• SiO2 ranging from 7 to 24.
• Due to its perfect cleavage, it is easy to
  extract slabs over a thickness of 20 mm to 50
  mm.
• Used for
• Flooring
• Wall construction
• Roofing.
• There are number of stone polishing industries
  developed basing on these flaggy Limestone in
  Andhra Pradesh.

13
Limestone Slabs contd..

• GOAP got estimation of these deposits and its
  grades through National Council for Cement and
  Building Materials (NCCBM) and DMG.
• There are about 200 million tonnes of such waste
  dumps, which consist mainly of flaggy limestone
  of irregular sizes
• These reserves could be made use of for the
  following purposes
• Manufacturing of ordinary Portland cement
• Blending with high quality cement grade Limestone
• Manufacturing of Masonry Cement
• Manufacturing Hydrated lime

14
Limestone Slabs contd..

• This will make way to
• Open the areas locked up of additional reserves
  of limestone
• Improving the environment.
• Manufacturing hydrated lime and masonry cement
• Assuming a basic minimum price of about Rs.800/-
  per tonne of hydrated lime and about Rs.2000 for
  masonry cement, about Rs.1400/- per tonne can be
  realized. For 100 million tonnes the value is
  about Rs.14000 crores.
• Assuming 20, as labour component on this Rs.2800
  crores can be set apart towards wages _at_ Rs. 200/-
  per day providing employment to about 2 lakh
  labour in the State.

15
Limestone Slabs contd..

• Also this waste can be used for making stone
  bricks of normal sizes like 9x4.5x4
• These bricks can be replace the traditional clay
  made bricks.
• Preserve the soil/clay for agricultural purposes.
  
• Use of cement and iron can be reduced since
  outside plastering of walls can be avoided and
  only line plastering is enough for wall
  construction.
• The stone bricks can also be used as pavement
  stone which is 2/3rd cheaper to the Granite
  pavement stone

16
Barytes Mining

• The Barytes deposit in Mangampeta village,
  Cuddapah district in Andhra Pradesh is unique
  with its bedded nature and grey in colour.
• It occurs in the form of two lensoid bodies
• Northern lense with a strike length of 1222
  meters and width of 90 meters occupying an area
  of 0.81 sq. kilometers
• Southern lense is located towards 700 meters
  south of northern lense with a strike length of
  300 meters and width of 80 meters occupying 0.11
  sq. kilometers.

17
Barytes Mining contd..

• The thickness of Barytes ranges from 16 to 40
  meters with a overburden ranging from 140 to 180
  meters.
• The total estimated reserves are 74.05 million
  tonnes.
• A.P.Mineral Development Corporation Ltd., is
  presently operating these mines since 1975.
• Corporation produced about
• 11 million tonnes of ore
• 40 million tonnes of overburden.

18
Barytes Mining contd..

• Overburden mainly consists of
• 75 of white shale
• 25 of black shale, which are otherwise called as
  volcanic tuff.
• Black shale
• Jet black having grayish striations with a
  thickness of about 30 to 45 centimeters.
• The Corporation is resorting to blasting as a
  result of which it develops multiple cracks and
  is thrown as waste.
• Samples are dressed to rectangular sized slabs
  after cutting and polishing, the results are
  found encouraging.

19
Barytes Mining contd..

• The 20 mm thickness slabs varying in sizes from 6
  centimeters to 45 centimeters in combinations can
  be produced.
• With a production cost taken as zero, since it is
  a waste, the black shale, after cutting and
  polishing _at_ Rs.5/- per sq.ft,(the cost taken on
  par with naturally occurring slabs elsewhere in
  the State), the same can also be equally
  marketed.

20
Barytes Mining contd..

• The total overburden so far removed is 40 million
  tonnes out of which if 25 is taken as black
  shale the reserves come to about 10 million
  tonnes.
• Out of this, even assuming 50 as useful
  recovery, about 3 million tonnes of black shale
  can be put to use for making slabs of different
  sizes. It comes to about 58 million sq.meters of
  slab.
• If the waste towards cutting and polishing is
  deducted we may get about 46 million sq.meters of
  slabs.

21
Barytes Mining contd..

• Assuming a production cost of Rs.50/- per
  sq.meter the value would be about Rs.230 crores.
  
• If these blocks are proved useful then instead of
  resorting to blasting the black shale can be cut
  into blocks using wiresaw so that the recovery
  percentage can be increased.

22
Clay

• Along with good grade Ball Clay there are huge
  quantities of inferior grade ferruginous clay,
  which are dumped as mine waste near the open cast
  mines of Dwarakatirumala, West Godavari district
  of A.P.
• The ferruginous clay occur as overburden to the
  Ball Clay in 5 1 ratio within Raghavapuram
  shales of Upper Gondwana formation.
• The production of the low-grade clay is Rs.20/-
  at mine head. The beneficiation cost works out to
  be Rs.200/-.

23
Clay contd..

• After beneficiation, the cost of the washed clay
  at plant is about Rs.800 per tonne. Already the
  Corporation established a clay washery near the
  site to utilize these clay dumps to produce high
  quality washed clay.
• There is still scope for establishing some more
  clay washeries to cater to the needs of micro
  ceramic and refractory industries.

24
Asbestos

• Chrysotile Asbestos occurs in the Vempalli
  formation of Cuddapah Super Group of rocks over a
  15 km Pulivendla belt of Cuddapah district.
• Serpentine, a Magnesium silicate, both in lemon
  yellow and green colour, is available in plenty
  as waste dumps near the Asbestos mines.
• Serpentine is also known to have the chemical
  nature to absorb the fluorine content in the
  water which could be tried for utilization for
  water treatment in the fluorine infested areas in
  Nalgonda district of A.P.

25
Asbestos contd..

• Serpentine dolomite are generally used in the
  manufacture of Mosaic tiles.
• there is a scope for establishing a unit to
  produce these chemicals from serpentine after
  conducting pilot plant studies market
  feasibility studies.

26
Dolomite

• M/s. Hindustan Zinc Ltd., have operated lead
  mines in Agnigundala in Guntur district, Andhra
  Pradesh.
• Lead deposit occurs in association with dolomite
  of Palnadu series of Kurnool sub.group.
• Lead concentrate was produced by crushing the
  host rock.
• The Dolomitic powder has piled up at the mine
  site as waste tailings.
• Useful for steel flexing by way of mixing with
  high-grade dolomitic powder.
• Detailed study of these reserves is worthy.

27
Slates

• A.P. is the largest producer of Slate in the
  country.
• Deposits of Slate occur in Prakasam, Guntur and
  Cuddapah districts.
• The Markapur Slate in Prakasam district is of
  high quality.
• Slates are being used for a variety of purposes
  such as wall clading, rooftop and other
  decorative purpose.
• Last year production of slates of export quality
  is 80,000 tonnes.

28
Slates contd..

• Taking 20 waste from the production of slates
  since last 15 years, about 2,40,000 tonnes is
  expected to be present covering a slate bearing
  stretch of about 10 km.
• The present sale price of designed slate is about
  Rs.180/- per sq.mt.
• Some industries are coming up using the waste to
  produce smaller size designed slates

29
Slates contd..

• There is a scope for some more units for wall
  cladding/paneling purposes as there are different
  coloured slates such as Black, Blue-black,
  Grey-blue, purple-green and red are available in
  plenty.

30
Tailings Derived Out Of Gold Mining

• The age-old mining for gold in Kolar Gold Fields
  have produced huge tailings, which are seen
  around Kolar Gold Fields.
• The total quantity estimated is 50 million
  tonnes. It also contains a little gold
  concentrate.
• Apart from the gold concentrate if these tailings
  are chemically analyzed, the same can be put to
  use for ceramic tile making.

31
Tailings Derived Out Of Gold Mining contd..

• By substituting the required mineralogical
  compositions for making ceramic tile mud, these
  reserves can be best utilized.
• It is a deserving Research Project. Also it can
  be used as reconstituted stone with a ceramic
  binder or resin binder or a cement binder.
  Presently this technique is in use at Europe as
  well as in Japan and Taiwan

32
Sandstone From Coal Mines

• Andhra Pradesh is one of the largest producers of
  coal from Gondwana Basin.
• The main rock that is derived from the overburden
  is sandstone with a thickness ranging from 30 to
  150 meters.
• Though here and there the sandstone is weathered,
  75 is hard, massive and varies in colour from
  brown to grey.
• Compressive strength of this sandstone is 250
  kg., for centimeter square.

33
Sandstone From Coal Mines contd..

• These sandstones removed in the process of
  opencast mining of coal by Singareni Collieries
  Co. Ltd., out 11 leases are in huge area
• These sandstones can be made use of by making
  decorative tiles, curb stones for pavement
  purposes.
• It has got good export value.
• Further, the weathered zone of sandstone can be
  used for making sand, which is an essential
  ingredient for construction activity.

34
Sandstone From Coal Mines contd..

• Due to recent alarming situation of depletion of
  ground water level due to indiscriminate removal
  of sand from the riverbeds, processed sand gained
  attention of the construction industry.
• Studies to make use of these sandstone deposits
  for variety of purposes so that waste dumps can
  be put to use is required.

35
RD for continuous studies on various aspects

• In Andhra Pradesh a share on profits derived by
  State owned Mining Corporation is set apart for
  taking up RD Activities
• Recently under this Scheme studies for
  beneficiation of low grade barytes could be made
  through National Metallurgical Laboratories (NML)
  Jamshedpur, which has resulted fruitfully.
• Other states may also take up such programmes if
  not yet taken up.

36
Conclusion

• In many areas, we may find lot of mineral waste.
  If extensive studies are made the said waste also
  can be put to use and it adds to the growth of
  the Nation by conserving the valuable and
  exhaustible mineral resource.

37
THANK YOU FOR PATIENT LISTENING