ABS BLENDED CEMENT We believe we are AT PAR WITH THE World's BEST http://cementconsultant.org/

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ABS BLENDED CEMENTWe believewe are AT PAR WITH
THE World's BEST http//cementconsultant.org/
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LOOKING BEYOND ORDINARY PORTLAND CEMENT

• The Cement Industry with annual worldwide
  production of around 1.5 billion tons is one of
  the largest users of high-grade limestone, coal,
  electricity other minerals.
• Each ton of cement requires 1.3 tons of
  limestone, 0.2 tons of coal around 100 kwh of
  electricity.
• Worldwide, cement production now accounts for
  more than 1.6 billion tons of CO2, or over 8 of
  total CO2 emissions from all human activities
  (Wilson 1993).
• It was the oil crisis of the 70s that made the
  world understand the evils of prolificacy of
  natural resources.
• The French, the Germans, the Japanese took the
  lead cause these were the countries blessed with
  little natural resources.

VSK in operation
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BLENDED CEMENT

• This led to the resurgence of blended cements.
  The thrust was clearly on conservance of natural
  resources, usage of waste materials on the
  durability of concrete.
• According to figures released by Cembureau (the
  European Cement Association), blended cement
  production in Europe during 1994 increased by 21
  percentage points to 51 of total cementitious
  production (from 30 in 1992).
• Portland cement production during the same period
  declined to 37 (from 52 in 1992). In the period
  from 1990 to 1995,
• The average clinker factor during this period
  (worldwide average) was reduced by more than 6.

Rotary Cement Plant
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BLENDED CEMENT IN INDIA

• Lafarge is the world leader in blended Cement
  technology
• Lafarge spends 5 of its turnover on RD
• Lafarge introduced a 16MPa one day strength
  cement with only 35 clinker ratio in the Indian
  market in 1999.
• Indian cement companies have been unable to
  decrease the clinker/cement ratio below 75 while
  maintaining the one day bench mark strength of
  16MPa.
• However blended cement production is up 15
  points now totalling 35 in the last two years as
  the Indian companies grapple to bring down costs
  improve cement quality in face of stiff
  competition from multinationals like CEMEX,
  LAFARGE etc

Blending Silos
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The NEED

• ABS Cement was set up at a cost of 4,00,000 in
  1991, with a term loan of 2,50,000 to
  manufacture 70 tpd OPC (Ordinary Portland Cement)
  using VSK technology.
• ABS made profits since inception repaid almost
  50 of the loan by 1996.
• However ABS had to be shut down for want of
  Limestone in 1996 as the Dehradun Limestone mines
  were closed following an order of the honourable
  Supreme Court.
• New product lines were required for survival.
• A need thus arose for the manufacture of Blended
  Cement.

Our VSK RAW MILL were sold in 2001
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THE BEGINNING

• The cost of the Rotary Clinker in India is 44
  PMT almost equivalent to the selling price of
  Cement.
• It is a well known fact that Clinker gives cement
  the early strength while the pozollan the later
  age strength.
• In 1998 we re-commenced production of Cement with
  65 clinker content balance being locally
  available pozollans.
• Our experiments to decrease the clinker content
  led to a cement with low one/three day strength
  which was unacceptable in the Indian Market.

Rotary Clinker received at ABS
Cement being packed
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ACI-Effect of fineness on cement

• The startling finding that the one/three day
  strength increases almost three fold if the
  fineness of cement goes up from 2500 blaines to
  4500 blaines( provided we maintain the desirable
  residue) was an important breakthrough.
• The effect of fineness on cement was published
  online by the American Concrete Institute in
  1999.

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Cement Fineness

• As our cement mill is designed for manufacturing
  cement at a maximum fineness of 3500 blaines
  further RD was required.
• With trial error we achieved our bench mark.
• Eight major changes had to be made to our cement
  mill to achieve the required fineness.
• These changes included
• Installing an on line Jaw crusher,
• Tinkering with the RPM of the cement mill,
• Changing Grinding media distribution etc etc.

On Line Jaw Crusher at ABS
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FLY ASH

• The only world class pozollan available near us
  was Class F Flyash containing less than 1 Carbon
• Fly is priced at a reasonable 8 PMT.
• This fly ash became the natural ingredient around
  which our research evolved.
• In1999 ABS trial marketed fly ash blended cement
  with 32 fly ash content.
• Indian standard IS 1489 permitted a maximum of
  25 fly ash content in cement.
• It was on our letter that the IS 1489 was
  AMMENDED to allow 35 fly ash addition in cement
  in 2001.
• We realized that if our technique was adopted the
  world can gainfully utilize 400 million tons of
  fly ash per year in cement alone.

Class F Fly Ash with 1 Carbon Note the colour
is off-white
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Calcined Clay Limestone

• Introduction of a pozollan is a time consuming
  affair as any material requires at least 6 months
  of extensive laboratory testing field trials.
• Emboldened we extended our research to calcined
  clay, low grade limestone their usage in
  cement.
• Our discussions with Bureau of Indian Standards
  (BIS), National Council For Cement Building
  Materials (NCCBM), the FLY ASH MISSION also
  paved way for the allowance of addition of
  low-grade raw limestone up to 5 in OPC cement.
• Further amendments including the allowance of
  more performance improvers in cement are under
  consideration.

Crushed Brick bats
Crushed Limestone
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AIR COOLED SLAG

• Cement Manufacture is all about incoming
  outgoing freight. Cement being an inexpensive
  commodity.
• Addition of GGBFS was out of question as the
  landed price was 32 PMT.
• We settled on air cooled slag from a local mini
  steel plant that was free excepting for the
  freight of 5 PMT.
• Although worldwide research on Air Cooled
  Slag-for usage in cement is not documented, we
  realized we were on the right track.

Air Cooled SLAG
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Alkali Activated Slag Additives

• To increase the one day strength we activated the
  slag by lime sludge etc.
• Further activators/accelerators were added.
• The Clinker/Cement ratio in 2002 stands at
  52.down from 65 three year ago.
• Research being a continuous process we hope to
  bring down the ratio by four percentage point
  this year to 48 by Sept this year.
• Thanks to Blended Cement, ABS has since repaid
  all outstanding loans to financial institutions.
• The 500 tpd Nirmaan Cement appointed us
  consultants to improve cement quality decrease
  their clinker ratio in 2001.

Lime sludge
Additives Accelerators being added
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Consistency in Cement

• ABS cement now had 7-8 pozollan/additives.
• We introduced the weighbridge system so that each
  ingredient could now be weighed for producing a
  cement consistent in quality.

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CEMENT INDIA

• The Journal Cement India showcased our cement for
  two years running on its website
  www.cementindia.net
• Several articles on blended cement and fly ash of
  ours were published by Cement India.
• At ABS our quest to produce better cement has
  just started.