1. A
REPORT ON WINTER TRAINING
On
"CEMENT MANUFACTURING PROCESS"
J.K. CEMENT LTD., NIMBAHERA
Vellore Institute of Technology, Vellore
DURING SESSION 2015-16
Guided By: Submitted to:
Mr. N K Vaishnav Mr. Shailendra Sharma
Sr. Officer – RTC Manager – HR & RTC
Submitted By:
Anshul Bhandari
13BCH0001
B. Tech (Chemical Process Engineering)
2. PREFACE
As per the requirement of engineering curriculum, J K Cement WORKS, Nimbahera has been
kind enough to permit me to complete my vocational training on “CEMENT
MANUFACTURING PROCESS”.
The internship report is a detailed submission on the cement making process starting from the
source to its final packing stage. It includes the unit operation, process equipments, control
systems, and the quality control analysis undergone by the JK Cement Works at Nimbahera
(Rajasthan).
(………………………………)
3. ACKNOWLEDGEMENT
It gives to me tremendous pleasure in acknowledge the invaluable assistance to me by various
personalities. In successful completion of this report, I express my gratitude towards Mr. S K
Rathore, Unit Head, and the entire management of J. K. Cement Works for giving me a chance
to work as a vocational trainee in their esteemed organization.
I wish to acknowledge my profound gratitude towards Shri M S Shekhawat, Asst. Vice
President – HR & IR for giving me opportunity in this field.
I also wish to acknowledge my profound gratitude towards Mr. Shailendra Sharma, Manager –
HR & RTC and Mr. N K Vaishnav, Sr. Officer - RTC for incessantly guiding me in-depth
training on “Cement Manufacturing Process”
I also wish to acknowledge my parents and university faculties who always encourage and
support me at every right step in my life.
(………………………)
4. An Introduction to
HR Department
JK Cement Works
Kailash Nagar, Nimbahera
District: Chittaurgarh-312617
(Rajasthan)
5. CONTENTS
1. Overview of J K Cement Works
1.1 The Company
1.2 About J K Cement
1.3 Grey Cement Plants and Production Capacity
1.4 Power Plant
2. Management Set- up.
3. Organizational Chart.
4. Regional Training Centre - North
5. Corporate Social Responsibility
6. Manufacturing of White Cement
7. Manufacturing of Grey Cement
8. A Passion for Quality - Characteristics of Cement
9. Preparation of Raw Meal
9.1 Mined and crushed raw material
9.2 Prehomogenization
9.3 Grinding
9.4 Homogenization
9.5 Raw Meal
10. Conclusion
11. Bibliography
6. 1. OVERVIEW OF J K CEMENT LTD.
1.1 The Company
Kamla Tower, Kanpur
J.K. Cement Ltd is an affiliate of the multi-disciplinary industrial conglomerate J.K.
Organisation which was founded by Lala Kamlapat Singhania. For over four decades, J.K.
Cement has partnered India's multi-sectoral infrastructure needs on the strength of its product
excellence, customer orientation and technology leadership The Company has over four decades
of experience in cement manufacturing. Our operations commenced with commercial production
at our first grey cement plant at Nimbahera in the state of Rajasthan in May 1975. Subsequently
the Company also set up 2 more units in Rajasthan at Mangrol and Gotan. In the year 2009 the
Company extended its footprint by setting up a green-field unit in Muddapur, Karnataka giving it
access to the markets of south-west India. In the year 2014, the company further expanded its
capacity in the north with brownfield expansion of 1.5 MTPA integrated unit at Mangrol and
split grinding unit of 1.5 MTPA at Jhajjar. Today J.K. Cement has an installed grey cement
capacity of 10.5 MTPA making it one of the leading manufacturers in the country.
The Company is the second largest manufacturer of white cement in India, with an annual
capacity of 600,000 tonnes in India. We are also the second largest producer of Wall putty in the
country with an annual installed capacity of 5,00,000 tonnes.
7. J.K. Cement was the first Company to install a captive power plant in the year 1987 at Bamania,
Rajasthan. J.K Cement is also the first cement Company to install a waste heat recovery power
plant to take care of the need of green power. Today at its different locations, the Company has
captive power generation capacity of over 140.MWs which include 23 MW of waste heat
recovery power plants.
The Company has made its first international foray with the setting up of a green-field dual
process white cement-cum-grey cement plant in the free trade zone at Fujairah, U.A.E to cater to
the GCC and African markets. The plant at Fujairah has a capacity of 0.6 million tonnes per
annum for White Cement with a flexibility to change over its operation to produce upto 1 million
tonnes per annum of Grey Cement.The commercial production from Fujairah Plant started from
Sep'2014.With this, J.K Cement Ltd has become the second largest White Cement Producer in
the World.
As a part of its new initiatives, the Company plans to increase the production capacity of Wall
Putty to keep pace with the rising demand .In this direction, the company plans to put up 6 lac
tonnes capacity at Katni in M.P.The first phase of 2 lacs tonnes will be taken up by the end of
Fiscal 16.
Backed by state-of-the-art technology, access to the best quality raw materials and highly skilled
manpower against the backdrop of India's infrastructural growth in an overdrive, we are upbeat
about the future. Superior products and a strong Brand name, an extensive marketing and
distribution network and the technical know-how represent the Company's abiding strengths.
8. 1.2 About J K Cement
J.K Cement has three decades of experience in cement manufacturing. From modest beginning in
the year 1974 with a capacity of 0.3 million tonnes at Nimbahera in Rajasthan, today J.K Cement
has 6 kilns of different capacities with a combined annual capacity of 7.5 million tonnes. The
three cement units having aggregate capacity of 4.5 million tonnes are located in Rajasthan at
Nimbahera (capacity 3.25 million TPA), Mangrol (capacity 0.75 million TPA) and Gotan
(capacity 0.47 million TPA) and one unit in Karnataka at Muddapur with capacity of 3 million
TPA. The Company is the second largest manufacturer of White Cement in India, with an annual
capacity of 400,000 tonnes and value-added building products such as Wall Putty.
The Company also has a fully automated plant of White Cement based Wall Putty having a
production capacity of 3 lac tonnes per annum. J.K. White Cement's plants are accredited with
ISO - 9001 and 14001 Certified Company by LRQA. Further, the plant is also OHSAS 18001
(For safety and environmental upkeep) accredited.
1.3 Grey Cement Plants and Production Capacity
We manufacture grey cement in two facilities located at Nimbahera and Mangrol in the state of
Rajasthan in Northern India. Our plants have obtained many accolades and recognition, the most
noteworthy being IMS Comprising of : ISO-9001:2008 for QMS and ISO-14001:2004 for EMS
for the grey cement facility at Nimbahera and Mangrol.
The following tables shows: PRESENT CAPACITY AND PERFORMANCE
CLINKER PRODUCTION – Nimbahera and Mangrol Plant
Plant Capacity ( Tonnes / day)
J K Plant, Nimbahera
I. Kiln 1200 II. Kiln 1650 III. Kiln 4700
TPD
7550
Unit 1 at Mangrol 2100
Unit 2 at Mangrol 5000
Total Capacity 14650 TPD
9. PRODUCTION ANALYSIS TABLE: IN TONS – Nimbahera and Mangrol Plant
Year Clinker Cement
2012 - 13 2955814 3567226
2013 – 14 3008736 3523527
2014 – 15 1961430 2378020
FINANCIAL ANALYSIS: IN Million – J K Cement Ltd.
1.3.1 J.K. Cement Works, Nimbahera
Commenced commercial production in 1975 with an
initial capacity of 0.3 MnTPA. In the year 1979, a
second production line was added to enhance the
production capacity to 0.72 MnTPA. 1982 witnessed the
incorporation of another production line taking the
production capacity to 1.14 MnTPA. In 1988 a pre-
calciner was installed and the production capacity
touched 1.54 MnTPA. Constant modernization and up-
gradation was instrumental in bringing the plant to its
present capacity of 3.25 MnTPA. Major modification to
reduce the electrical energy cost & to utilize the waste
heat at maximum, Waste Heat Recovery System of 13.2
MW was installed in the year 2007-2008.Recognition:
IMS comprising of ISO-9001:2008 for QMS and ISO-
14001:2004 for EMS.
Nimbahera
Year Turnover PBT
2012 - 13 3342.58 337.54
2013 – 14 3201.72 114.18
2014 – 15 3859.40 144.10
10. 1.3.2 J.K. Cement Works, Mangrol
Commenced commercial production in Dec'2001 with a capacity of 0.75 MnTPA. It is situated
close to Nimbahera plant (10kms away) - offers it significant synergy benefits like assistance
from technical & commercial staff of Nimbahera Complex. The current capacity is 1.0
MnTPA. We are also starting work on a brown field expansion at Mangrol having a capacity of
3 MnTPA, integrated plant with 1.5 Mn. TPA cement grinding capacity, 25 MW Captive
power plant and 10 MW Waste Heat Recovery plant.
1.3.3 J.K. Cement Works, Muddapur
It is situated near Muddapur village of taluka - Mudhol, District - Bagalkot (Karnataka) and has
the latest state of art technology to manufacture 3.0 Million tonnes of cement per annum. The
commercial production at Muddapur started in September, 2009 and the despatch commenced in
October, 2009. The plant has the latest and the most modern dry process pre-calcination
technology with sophisticated state of the art technology and control system from Internationally
renowned firms like FL Smidth, Tahio Engineering Corporation, Japan and others for
manufacturing cement with robotic technology and to ensure top quality cement consistently.
The best equipments available in the global market have found their way into the plant making it
the most modern plant. The plant has a 6500 TPD kiln. The cement production capacity of the
plant is upto 3.0 Milliontons per annum based on the quantum of OPC, PPC and Slag Cement.
1.3.4 J.K. White Cement Works, Gotan
Our pioneering foray into white cement 25 years ago created a new chapter in the history of J.K.
Cement and the J.K. White Cement Plant is an integral part of the same.
We were the first White Cement facility in India, which was limestone based, and manufactured
Cement through the dry process. The White Cement plant was commissioned in 1984 at Gotan,
Rajasthan, with an initial production capacity of 50,000 tons. The White Cement plant uses
technical expertise from F.L. Smidth & Co. from Denmark and state of the art technology with
11. continuous on-line quality control by micro processors and X-rays ensure that only the purest
White Cement is produced. Over the years, continuous process improvements & modifications
have increased the plant's production capacity to 400,000 tons per annum.
1.3.5 J.K. Cement Works, Fujairah
The Foundation Stone being laid by H.H. Sheikh Mohammed Bin Hamad Al Sharqi - Crown
Prince of Fujairah along with Shri Yadupati Singhania - MD & CEO, J.K. Cement Ltd. and Shri
Raghavpat Singhania - Special Executive.
J.K. Cement Ltd. has added yet another feather to its cap with the announcement of its maiden
overseas plant at Fujairah, UAE which has a capital outlay of US $ 150 million. The plant's
foundation stone laying ceremony was held on November 14th, 2011in the presence of His
Highness H.H. Sheikh Mohammed Bin Hamad Al Sharqi - Crown Prince of Fujairah. Also
gracing the occasion were Shri Yadupati Singhania – MD & CEO, J.K. Cement Ltd., Shri
Raghavpat Singhania – Special Executive, Mr. A.K. Saraogi – CFO & President (CA), Mr. N.
Gowrishankar – Unit Head (J.K. Cement Works, Fujairah) and Mr. D. Ravisankar – President,
J.K. Cement Works, Nimbahera.
The capacity of the Grey cum White cement plant is slated to be at 1,750 tonnes per day (tpd) for
White Cement clinker and 2,800 tonnes per day (TPD) Grey cement clinker.
The Commercial production from the plant started from Sep'14.
12. The plant at Fujairah has a capacity of 0.6 million tonnes per annum for White Cement with a
flexibility to change over its operation to produce upto 1 million tonnes per annum of Grey
Cement. The plant shall have the flexibility to have 100% white cement, a mix both of white
cement and grey cement or 100% grey cement, depending upon the market demand. Thus, the
Company plans to cater to the demand in the region as well as to the neighbouring countries
through this manufacturing facility.
As has been a ritual with J.K. Cement Ltd., in this venture as well, we will continually strive to
uphold the quality consciousness, customer experience and best ethical practices that J.K.
Cement Ltd. is known for.
1.4 Power Plants
All our plants have captive power facilities except grinding unit at Jhajjar. Infact, J.K. Cement
was the first Company to install captive power plant in the year 1987. J.K Cement is also the first
cement Company to install a waste heat recovery power plant to take care of the need of green
power. Today at its different locations, the Company has captive power generation facilities of
over 140.7 MWs including Waste Heat Recovery of 23.2 M.W.
13. 2. MANAGEMENT SET- UP
2.1 Corporate Level- Kanpur
Chairman & Managing Director - Shri Y P Singhania
Special Executives - Shri Raghavpat Singhania
Shri Madhavkrishna Singhania
Business Head - Shri Rajnish Kapur
2.2 Heads:
Project
President Project Shri D Ravishankar
Units
Unit Head Shri S K Rathore
J K Cement, Nimbahera and Mangrol,
Distt: Chittaurgarh, Rajasthan
Unit Head Shri A K Jain
JK Cement Works, Muddapur,Distt:
Bagalkot, Karnataka
President - Works Shri B K Arora
J K Cement- White and Grey Plants at
Gotan, Distt: Nagaur, Rajasthan
14. 3. ORGANISATIONAL CHART
J K Cement Ltd.
Production & Location
J K Cement
Works,
Mangrol
(Raj.)
Unit 1 & 2
Grey
Cement–
7100 TPD
J K
Thermal
Power,
Bamania
(Raj.)
CPP – 15
MW
J K
Cement,
Mudhol,
Karnataka
Grey
Cement –
9000 TPD
CPP– 50
MW
J K Cement,
Gotan (Raj.)
White Cement
–1000 TPD
Grey Cement
– 1200 TPD
CPP – 7.5MW
J K Cement
Works,
Nimbahera
(Raj.)
Grey Cement–
7550 TPD
CPP – 22MW
WHR–13.2 MW
ABROAD:
JK Cement
Fuzairah,
UAE
White and
Grey Cement
2800TPD
J K Organization
15. 4. Regional Training Centre: Nimbahera
The Regional Training Centre - North is a premier training centre of India promoted with
assistance from World Bank, DANIDA and Govt. of India as a unique HRD project in Cement
Industry. It is equipped with modern training aids and caters to the skill enhancement and
competency developmental needs of more than 20 cement and other plants. It has trained over
13000 technical and managerial personnel during the last 21 years.
The centre has conducted many tailor-made in-house programs for cement and other industries in
India and abroad including for Oman Cement, Oman and Star Cement, Dubai and Hama Cement,
Syria / EHDASSE Sanat Corp.Iran and NCC Yemen.RTC has specialized packages / modules in
Mining, Process, Maintenance disciplines like Operation & Maintenance of HEMM / Gear-boxes
/ Pumps / Compressors / Electrical & Electronics Equipments / Energy Conservation
/Environment Management and Machinery Alignment, etc. designed and developed by renowned
International / National agencies like FLS Denmark, NCCBM, TATA Interactive Systems, VEC,
NITTTR, etc. More than 100 senior line mangers from ten plants have been trained at Denmark,
NITTTR, Bhopal and Chennai, who act as resource persons. Besides OEM's and management
experts of national repute are invited to make these programs effective and gainful experience for
the participants.
16. RTC VISION Be a premier centre of excellence in competency development of
human resources in cement,mining and other industries for meeting
the techno-economic challenges under globalized environment.
RTC MISSION RTC seeks to develop ordinary manpower to produce extra ordinary
results by providing the best inputs of learning to help industry
generate surpluses with sensitivity towards environment, quality and
cost.
RTC OBJECTIVE To prepare the employees of Cement and other industries by
developing desired competencies for meeting the requirements of
present and future roles.
To develop and maintain a pool of competent technocrats and
managers to meet the emerging challenges of competition &
growth.
To help people strive for innovative solutions and create a passion
for quality, energy, Environment conservation and optimization
of resources.
5. CORPORATE SOCIAL RESPONSIBILITY
J K Cement has contributed significantly to the development of various services in and around its
offices and plants. Some of such activities can be enumerated as under :
Education Schools and University:
Dr Gaur Hari Singhania Institute of Management & Research, Kanpur
Sir Padampat Singhania Technical University at Bhatewar, Udaipur.
J K Institute of Technology – JKIT at Nimbahera
Padam Vidya Vihar – Primary School at Nimbahera
Kailash Vidya Vihar – Sr Secondary School at Nimbahera
Sr Secondary School, Gotan
17. Educational services:
Construction of rooms in Govt. College at Nimbahera.
Running JK Institute of Technology, ITI in five trades affiliated to NCVT.
Running 10+2 CBSE affiliated school
Running Regional Training Centre for Cement technocrat’s aided by WorldBank &
DANIDA.
Various constructions in nearby Govt. Schools of Chittorgarh district.
We are involved in girls school (under construction) and committed reasonable financial
contribution for above
Medical services
Rs. 36 lacks contribution for the construction of govt. Hospital at Nimbahera.
Ambulance to govt. Hospital.
Free facility of pathological laboratory for the persons of surrounding area.
Financial contribution to various NGOS for medical camps in the district.
Financial contribution for construction of dispensary & health centre in nearby villages.
Free Homeopathic consultancy/medicines for the patients of nearby area.
Religious services
Radhakrishna temple at colony premises.
prayer hall in hanuman temple in Nimbahera.
Bheemkeshwar temple in staff colony.
Dharmashala at Bhanwarmata (tourist/ religious place).
8 rooms for Dharamshala at Pashupati Nath temple in Mandsaur (M.P.).
Various temples in number of nearby villages.
Sports services
Sports infrastructure like wooden badminton court, table tennis court, billiard room, and
cricket ground, volleyball ground in colony campus.
Sponsoring all India youth football, volley ball and badminton tournaments.
18. Sponsoring inter-district tournaments.
Arranging summer camps for various sports.
Other social services
Construction of approach roads in and around villages of mining area.
Digging of tube wells.
Supply of tube well pumps.
Construction of water tanks.
Supply of drinking water in tankers in nearby needy places during summer.
Regular plantation in plant, colony and nearby villages.
Direct and indirect employment to thousands of persons of surrounding area.
Financial helps to NGOS.
Financial aid to organize religious festivals by municipal board.
6. Manufacturing Process - White Cement
At J.K. White Cement Works, Gotan we use technical expertise from F.L. Smidth & Co. from
Denmark and state of the art technology with continuous on-line quality control by micro
processors and X-rays to ensure that only the purest White Cement is produced. We manufacture
White Portland Cement through these 5 significant stages - Crushing, raw meal grinding,
clinkerisation, cement grinding and packing for dispatch.
At raw mill, crushed limestone, clays and feldspar of desired chemical compositions are fed
through electronic weigh feeders.
Clinkerisation is the heart of cement manufacturing process, where the raw material is fed to
pre-heater at controlled rate through electronic weigh feeder. The feed enters the kiln through
cyclones and fuel is fired at the kiln outlet end.
Clinker and gypsum are fed to the cement mills through electronic weigh feeders at controlled
rate and ground in ball mills. The classifier (high efficiency separator) controls the fineness of
white cement. The finished product of desired chemical composition and physical properties
is transported to Cement Silos for storage.
19. White cement is drawn from cement silos, for packing in bags by electronic rotary packer and
in small pouches by Fill, Form and Seal machines..
Step 1 (Mining) Step 2 (Crushing) Step 3 (Grinding) Step 4 (Fuel Preparation)
Step 5 (Kiln Operations) Step 6 (Cement Grinding) Step 7 (Packing Process) Step 8 (Loading Process)
7. Manufacturing Process - Grey Cement
The production process for cement consists of drying, grinding and mixing limestone and
additives like bauxite and iron ore into a powder known as "raw meal". The raw meal is then
heated and burned in a pre-heater and kiln and then cooled in an air cooling system to form a
semi-finished product, known as a clinker. Clinker (95%) is cooled by air and subsequently
ground with gypsum (5%) to form Ordinary Portland Cement ("OPC"). Other forms of cement
require increased blending with other raw materials. Blending of clinker with other materials
helps impart key characteristics to cement, which eventually govern its end use.
20. All J.K. Cement plants are dry process plants. Limestone is crushed to a uniform and usable size,
blended with certain additives (such as iron ore and bauxite) and discharged to a vertical roller
mill/Ball Mill, where the raw materials are ground to fine powder. An electrostatic precipitator
dedusts the raw mill gases and collects the raw meal for a series of further stages of blending.
The homogenized raw meal thus extracted is pumped to the top of a preheater by mechanical
transport /FK pumps. In the preheaters the material is heated to 750ºC. Subsequently, the raw
meal undergoes a process of calcination in a precalcinator (in which the carbonates present are
reduced to oxides) and is then fed to the kiln. The remaining calcination and clinkerization
reactions are completed in the kiln where the temperature is raised to between 1,450ºC and
1,500ºC. The clinker formed is cooled and conveyed to the clinker silo from where it is extracted
and transported to the cement mills for producing cement. For producing OPC, clinker and
gypsum are used , for producing Portland [Pozzolana] Cement ("PPC"), clinker, gypsum and fly
ash are used and for producing Portland Slag Cement (PSC), cement uses clinker , gypsum and
slag.
The JK Cement has adopted the latest technology of manufacture of cement by dry process with
suspension pre heater and pre calcination. The unit has selected the dry process for the
manufacturing of cement because the fuel consumption in dry process of cement manufacture is
less; compared to wet process, The coal consumption ratio of wet and dry process is about 1.3: 1.
However, in the case of dry process power consumption is higher. The present worldwide trend
in cement industry is to put up all plants with dry process mainly because of the overall economy
and lesser need of water resources.
RAW MATERIALS USED
1) Lime Stone
2) Gypsum
3) Laterite
4) Alumina
5) Coal
6) Fly Ash
21. STAGES OF MANUFACTURING PROCESS
STAGE I - MINING
Maliakhera, Karoonda and Tilakhera are the mines feeding the plants. Open cast mining
technique is used. The limestone is transported to the crusher hopper through conveyor belts and
dumpers.
STAGE II - CRUSHER
The limestone is crushed to the standard size for feeding the Raw Mill.
STAGE III - STACKER RECLAIMER
The stacker is used to make huge stockpiles of crushed raw material while the reclaimer picks up
the required quantity of raw material from the stockpiles and feed them into the Raw Mill
through a belt conveyor.
STAGE IV - RAW MEAL HOPPER
There are different hoppers for storing crushed Limestone, Alumina, Laterite & Gypsum, before
being fed into the Raw Mill.
STAGE V - RAW MILL
All these components of raw mix are put through grinding mills and then properly homogenized
and stored in silos.
STAGE VI - KILN
The materials from the silos are fed to the kiln through automatic weigh feeders. The hot flue
gases from the kiln passes through pre heater where raw meal gets partly calcinied and converted
into clinker at a temperature of about 1400 degree centigrade in the main burning zone of the
kiln.
STAGE VII - COAL SECTION
Bituminous and Lignite varieties of coal are used here. The coal from the stock yard is fed into
the coal crusher from where the crushed coal is stored in the coal hopper. This coal to be used as
fuel for the kiln is crushed, pulverized and fed into the kiln along with primary air.
22. STAGE VIII - CLINKER STORAGE
After the coal is fired into the kiln and the raw meal undergoes chemical reactions, the product,
which emerges, is called the clinker. The clinker obtained from the kiln is cooled and transported
to the clinker storage yard through pan - conveyors.
STAGE IX - CEMENT MILL
The material from the clinker storage is fed into the clinker hopper and gypsum into the gypsum
hopper. The proportionate mixture of gypsum and clinker in the crushed form is sent to the
cement mill, which grinds it into fine powder called cement.
STAGE X - PACKING AND DISPATCH
The cement from the cement mill is pneumatically fed into cement storage silos from where it is
packed in HDPE bags by rotary packing machine and then directly loaded into wagons or trucks.
The complete process is controlled by a most modern process control instrumentation system.
There is a well-equipped laboratory for controlling the quality of the product at various stages in
its manufacturing process.
8. A Passion for Quality – Characteristics of Cement
At J.K. Cement, quality is not just a product centric vision but an Omni-organisational vision.
With a firm belief that quality begins and ends with people, the management has inculcated a
quality culture in the very thought process of the organisation.
23. J.K. Cement Works - Nimbahera & Mangrol
J.K. Cement has effectively pledged its reputation as the market leader in quality of cement
manufactured. At Nimbahera and Mangrol, our labs are equipped with State-of-the-art Process
control instrumentation and quality control system. The testing laboratory is manned by qualified
personnel to ensure quality of product comparable to the best available in the market at all times.
The quality management system at J.K. Cement Works is certified by the Prestigeous Lloyds
Register for quality assurance since the year 1995.
Our plants are also ISO 9001:2008 & ISO 14001:2004 certified and are in the process of getting
our laboratory accredited with the NABL-National Accreditation Board for Testing and
Calibration Laboratories.
Locate our Plants
Grey and White Cement Works
NIMBAHERA
Nimbahera Dist - Chittorgarh,
Kailash Nagar - 1,
Rajasthan – 312617
Phone - 01477 - 220087
MANGROL
Mangrol, Tehsil Nimbahera
Dist - Chittorgarh, Rajasthan
Phone - 01477 - 246324
25. 9. Preparation of Raw Meal
Raw Meal is prepared from the mined raw materials in the following way:-
Mined and Crushed
Raw Material
Prehomogenization
Grinding
Homogenization
RAW MEAL
26. 9.1 Mined and Crushed Raw Material
Drill Compound Impact Crusher
The raw material is mined by blasting the mining sites using ammonia and fuel. An
approximately 8 meters of bench height is maintained for mining in JK Cements, Nimbahera
(Rajasthan). Also there are some other specifications like there should be a minimum of 4 meters
of distance between 2 successive holes and also there should be a minimum difference of 23
milliseconds between 2 successive blasts. Also a minimum of 300 meters of distance is to be
maintained from the blasting site for safety purposes.
The dumpers carry mined limestone from quarry to crushing plant where crushers are used for
coarse size reduction of limestone. Mainly three types of crushers are used:
1) Double Toggle Jaw Crusher
2) Double Swing Hammer Crusher
3) Single Rotor Impact Crusher
The mined limestone is first fed to the unloading hopper that has a maximum size allowance of
1m X 1.5m and has a capacity of 300 MT. This feed is then send to the main crusher
(Compound Impact type) having a rated capacity of 800TPH which gives an output size of less
than 40mm which is further send for prehomogenization process via Rubber Belt Conveyers
(RBCs)
27. 9.2 Prehomogenization
Linear Stacker (Chevron Formation) Scraper Reclaimer
Prehomogenization process involves stacking of crushed run of mined limestone onto a stock
pile and subsequently reclaimed in such a way that the inherent fluctuations in the Calcium
Carbonate (CaCO3) content are evened out.
The mined and crushed raw material is then transported from crusher to the stock piling site
using Rubber Belt Conveyors (RBCs) where the material is stacked either in chevron type
(longitudinal direction) or in windrow type (Linear direction). For this purpose, two types of
stackers can be used; either linear stacker that gives a longitudinal stock pile or circular stacker
that gives a circular stock pile with an arc formed by circular rotation of boom delivery point.
Finally a scraper reclaimer is used that evens out the fluctuations in CaCO3 content of raw
material. It uses a narrow rake covering the whole surface of pile. Its motion causes the particles
to roll down the slope. They are further reclaimed by the scraper chain moving in lateral
direction at the pile’s base.
The JK Cement Works uses a Swing Boom Luffing type stacker which forms a Chevron type
stock pile of capacity 30,000MT and is further reclaimed by Bridge type Scraper Reclaimer.
28. 9.3 Grinding
The prehomogenized raw material is then stored in supply hopper for fine size reduction.
Additional hoppers are used either for storing additives such as sandstone, Iron Oxide, etc or for
storage of corrective materials such as Laterite. The mixture is then ground in the raw mills and
the hot gases escaping from the pre heater exit are used for drying. For grinding purpose either
vertical raw mills or ball mills are used. Parallel to grinding, dust collectors either Bag Filters or
Electrostatic Precipitators (ESPs) are used for dust removal.
The JK Cement Works uses two Hammer Mills (200TPH) as secondary crusher which reduces
the prehomogenized raw material to 25 mm size from 40 mm input size and further sends it to
Ball Mills (RM1, RM2 and RM3) which further reduces size to 170 mesh. Apart from the
secondary crusher, the prehomogenized raw material, 40 mm in size, is directly send to the
Vertical Roller Mill (VRM 4) which gives an output size of 170 mesh. This grinded raw meal is
then stored in silos for further homogenization.
Prehomogenized
Raw Material
(40mm)
Secondary Crusher
(Hammer Mill)
(25mm)
Ball Mill (RM 1)
(170 mesh)
Ball Mill (RM 2)
(170 mesh)
Ball Mill (RM 3)
(170 mesh)
Vertical Roller Mill
(VRM4)
(170 mesh)
29. 9.4 Homogenization
The grinded raw material from the raw mills either the Ball mills or the Vertical raw mill is
stored in silos. In the silos homogenization process take place in which additives and corrective
materials are added and blended uniformly by passing compressed air to form required raw meal.
The compressed air can be passed either mechanically or pneumatically that involves porous
ceramic plates/fabric covered boxes permeable to air that passes to porous plates to fluidize the
raw meal stored in silos.
9.5 Raw Meal
Pyroprocessing (Rotary Kiln)
Finally raw meal is prepared which is further used for formation of clinker and cement at later
stages. This raw meal is then sent to kiln via pre heaters and pre calciner to form clinker which is
further cooled and is stored in silos. This clinker as per demand and requirement is taken from
the silos, grinded and then mixed with appropriate amount of Gypsum to form cement. Finally
the processed cement is send to packaging plant.
30. The JK Cement Works, Nimbahera uses Suspension Pre heater kiln type Pyroprocessing
technique to form clinker that consists of Pre heaters, pre calciner and rotary kiln. The clinker so
formed is then cooled and grinded by the ball mills. Gypsum is added to the crushed clinker to
alter the settling time of cement in the cement mill. In the plant there are 6 cement mills in which
the first and second one works individually while third and sixth; and fourth and fifth are coupled
to give processed cement.
Finally this cement is send to packaging plant where either mechanically or pneumatically
packing machines are used to fill cements in 50Kg bags which are finally forwarded to the
Loading Station.
Packing Station Loading Station
31. 10. CONCLUSION
The report focuses on the initial stages of Cement manufacturing process i.e. preparation of raw
meal from the mined and crushed raw material which is further used for making clinker and then
cement.
The limestone mined from the site has different grades and thus it is then prehomogenized so as
to obtain evened CaCO3 content which is further grinded and additives and corrective materials
are added to it in homogenization process which makes it suitable for Pyroprocessing and further
processes.
32. 11. BIBLIOGRAPHY
Books and Authors
Portland Cement 2nd Ed., Thomas Telford
Natural Cement Comes Back", October 1941, Popular Science
WEB SITE
www.jkcement.com
www.rtcnorthindia.org
