This document discusses the promotion of using foundry slag waste from iron and steel production in foundries as an aggregate in paver block making. It begins by providing background on foundry slag waste and the Indian foundry sector, noting that approximately 5 lakh tonnes of slag waste is generated annually. It then describes the development of a technology to produce paver blocks by completely replacing coarse and fine aggregates with foundry slag. Test results found that paver blocks produced this way met strength standards. The document concludes by outlining the business potential and costs for setting up an enterprise to produce paver blocks using this waste-to-resource process.

1. Promotion of Technology for
Utilization of Slag Waste from
Foundries
in
Paver Block Making
Kolkata
20 January 2016
NSTEDB
Department of Science & Technology
Government of India
1

2. NSTEDB
Department of Science & Technology
Government of India
2

3. Secondary Raw Materials
WASTE MATERIALS
oIndustrial
oAsh
oMarble Sludge
oFoundry Waste
oEtc.
POTENTIAL USE
Material Process End Use
Plain
Concrete
Crushed Aggregate
Fresh
Concrete
Washed to remove
cement & recover
aggregate
Aggregate
Reinforced
Concrete
Crushed & Steel bars
removed
Steel recycled
Crushed
Concrete reused as
aggregate
NSTEDB
Department of Science & Technology
Government of India
3

4. What is foundry slag waste?
NSTEDB
Department of Science & Technology
Government of India
o The slag is a non-metallic inert by-product
primarily consists of silicates, alumina silicates
and calcium alumina-silicates produced during
production of iron and steel in foundry units
Batala
Jalandhar
Ludhiana
Delhi
Agra
Indore
HowrahRajkot
Ajmer
Mumbai
Kolhapur
Chennai
Jaipur
Ahmedabad Bhopal
Bhavnagar
Belgaum
Coimbatore
There are approx 5,500
units in the Country
located in the areas
marked in the map
engaged in various
types of metal castings
4

5. Indian foundry sector… at a glance
NSTEDB
Department of Science & Technology
Government of India
Casting production
- Fourth largest casting producer in world
- Annual production – 10 million tonnes (approx.)
Decentralized unorganized production
- Decentralized production > 5,500 units
- Annual turnover – Rs. 400 billion
- Employment to 0.5 million workers (direct) and 1.5 million
workers (indirect)
Resource intensive process
- 90% small to medium using cupola technology
- Low productivity and high energy consumption
- No pollution control measure
5

6. Indian foundry sector… at a glance
NSTEDB
Department of Science & Technology
Government of India
Slag generated
is approximately
10% of the total
production
#source-The Institute of Indian
Foundrymen
6

7. Challenge identified
NSTEDB
Department of Science & Technology
Government of India
Waste generation
- Slag waste generation – 5 lakh tonnes/ annum (approx.)
Use
- Slag dumped in open field, barren land
7

8. NSTEDB
Department of Science & Technology
Government of India
8

9. NSTEDB
Department of Science & Technology
Government of India
9

10. Howrah foundry sector… at a glance
NSTEDB
Department of Science & Technology
Government of India
Technology used
- DB Cupola furnace
Production
- No. of units > 200 units
Raw materials
- High ash coke, metal and limestone
Slag generated*
- 60,000 metric tonnes/ year
10

11. Current Building
Material Technology
Scarcity of natural sand/
aggregate
Soil and land
pollution
High cost of
building material
Introduction of
New Technology
Project Intervention
Reduced Pollution
Reduced Cost of
Building Material
Dissemination
Co-Benefits for
Environment, Business
& People
Dissemination
11

12. NSTEDB
Department of Science & Technology
Government of India
Innovative Solutions
12

13. Technology developed
NSTEDB
Department of Science & Technology
Government of India
• Methodology developed for replacement of
coarse and fine aggregates, used in conventional
production of Paver Blocks
• Paving blocks produced by completely replacing
6-8 mm aggregate with Foundry Slag
• A lab scale plant set up at Datia, Madhya Pradesh
13

14. NSTEDB
Department of Science & Technology
Government of India
Foundry Slag Grinding
14

15. NSTEDB
Department of Science & Technology
Government of India
8 – 10 mm foundry slag aggregate
15

16. NSTEDB
Department of Science & Technology
Government of India
Foundry Slag Based Paver Block
Production Unit
16

17. 17
Foundry Slag Waste Utilization
Enterprise details
• Micro enterprise ~ Rs. 25 lakhs investment
• Product - Paving block (can be expanded to other
building materials with low CAPEX)
• Working days - 300 in a year
• Production capacity - 1500 blocks per day
Foundry slag waste requirement
• Paving block - Approximate 5 kg weight (hexagonal)
• Composition - 1:4:4 (M30 grade)
• Raw materials - Cement, sand, foundry slag waste aggregate
• Annual consumption - 1,000 Tons per enterprise
Impacts
• Jobs created - 6-8 persons
• Waste utilized - 1,000 Tons per year
• Business generated - Rs. 72 lakhs/ year (Rs. 16 per block)

18. Product certification
NSTEDB
Department of Science & Technology
Government of India
The paving blocks produced by using the foundry slag were tested by the
NIT Bhopal and Shriram Institute for Industrial Research, New Delhi
The results up till M30 grade blocks were found to be very positive and duly
complying to IS 15658:2006
The Compressive Strength test results of M30/ M40 grade blocks were
found to be higher than those manufactured by using aggregate
18

19. Product certification
NSTEDB
Department of Science & Technology
Government of India
19

20. NSTEDB
Department of Science & Technology
Government of India
20
The Technology Package
o Processing of foundry slag waste through medium duty jaw crushers
o Use of OPC grade cement
o Mixing of concrete through ordinary concrete mixers
o Production through vibration in table vibrators
o PVC moulds for shaping
o Open atmosphere curing for 7 days

21. Market opportunity
NSTEDB
Department of Science & Technology
Government of India
• Howrah district
• Rural road – 948.68 kms**
• Pavers required – 960 lakhs numbers*
• Metro rail
• Private housing
• Shopping mall
• Petrol pump
• Tourism park
Sources:
* http://dcmsme.gov.in/dips/HOWRAH_wb.pdf
21

22. The business
NSTEDB
Department of Science & Technology
Government of India
22
CAPEX (CAPITAL COSTS)
Vibrating table - Rs. 3 lakhs
Moulds (2000 nos.) - Rs. 6 lakhs
Jaw crusher - Rs. 3 lakhs
Concrete mixer - Rs. 1 lakhs
Miscellaneous - Rs. 1 lakhs
Infrastructure (shed, office, electricity etc.) - Rs. 6 lakhs
Total investment - Rs. 20 lakhs
OPEX (WORKING CAPITAL)
For a period of 1 month including raw
material, labour, electricity etc. - Rs. 10 lakhs
Total investment ~ Rs. 30 lakhs (approx.)
(excluding land)

23. The business
NSTEDB
Department of Science & Technology
Government of India
ASSUMPTIONS
Selling price of a hexagonal paving block - Rs. 15 per block
Production period - 300 days
No. of units per day - 1500 nos.
Total production per year – 4,50,000 units
23
Existing production technology
Raw material
Cement 3.60
Stone aggregate 4.35
Sand 2.15
Manpower 1.50
Energy 0.95
Overheads 1.30
TOTAL 13.85
Slag based technology
Raw material
Cement 3.60
Foundry slag 2.60
Sand 2.15
Manpower 1.50
Energy 0.95
Overheads 1.30
TOTAL 12.10

24. The business
NSTEDB
Department of Science & Technology
Government of India
24
ASSUMPTIONS
Selling price of a hexagonal paving block - Rs. 16 per block
Production period - 300 days
No. of units per day - 1500 nos.
Total production per year – 4,50,000 units
PROFITABILITY IN EXISTING PAVING BLOCK PRODUCTION (FROM SINGLE
MACHINE)
Production cost - Rs. 13.85 per block
(including expenses and bank loan returns)
 Profitability - Rs. 9.5 lakhs per year
PROFITABILITY IN FOUNDRY SLAG WASTE BASED PAVING BLOCK
PRODUCTION (FROM SINGLE MACHINE)
Production cost - Rs. 12 per block
(including expenses and bank loan returns)
 Profitability - Rs. 18 lakhs per year

25. The enterprise establishment cost
NSTEDB
Department of Science & Technology
Government of India
The establishment of an enterprise can be financed through the PMEGP scheme of the
Ministry of MSME
Total project cost – Rs. 25 lakhs
• Entrepreneur’s contribution – 2.5 lakhs
• Term loan (from Banks) – 15.75 lakhs
• Govt. of India subsidy – 6.75 lakhs
PMEGP (Prime Minister’s Employment Generation Programme) scheme (KVIC)
• General Category
• Urban – 15%
• Rural – 25%
• Entrepreneur’s contribution – 10%
• Special Category
• Urban – 25%
• Rural – 35%
• Entrepreneur’s contribution – 5%
25

26. NSTEDB
Department of Science & Technology
Government of India
Thanks
26