Samalkha foundries melt on coke for chaff cutter castings: how much CO2, and does a divided blast cupola help?
Yes. A divided blast cupola takes coke from 150 to 200 kg per tonne of liquid metal to about 100 kg; the cluster profile counts on 25 to 30% less coke, paid back within a year. Samalkha's 30 working foundries burn about 4,560 t of coke a year, roughly 13,800 t CO2, for 36,000 t of castings.
The cluster
- About 50 foundries, of which about 30 operate, along GT Road and in the HSIDC estate.
- About 22 units make around 120 t a month of chaff cutters and cane crushers; about 8 make around 50 t a month of motor casings, impellers and pump parts.
- Chaff cutters are about 70% of output, cane crushers 15%.
- Only two foundries melt in induction furnaces. About 10 cupolas are already divided blast.
- Coke is about 90% of the cluster's 3,300 toe; electricity is 4.1 million kWh.
Your unit's CO2 per tonne
The profile's typical unit makes 600 t of saleable castings with 75 t of coke and 60,000 kWh. Coke at 3.02 t CO2 per tonne gives 227 t, power at 0.675 kg per kWh gives 41 t: about 0.45 t CO2 per tonne of castings. The larger 1,440 t unit lands at about the same, so cutting coke is the only lever that moves the figure much.
What else cuts coke
- A blower sized to the cupola's inner diameter: about 5% less coke. Most local blowers are not.
- Standard cupola operating practice: 5 to 10%.
- Rejections of 10 to 15% brought below 5%, with little spending.
- Shot blasting sand off runners and risers before remelting.
- Testing coke ash: low ash coke sold at 12% often runs above 15%.
Funding the switch
Samalkha is not on the first-phase ADEETIE cluster list, so a bank's energy efficiency or green loan is the usual route. A lender will want your coke per tonne before and after, from purchase bills and melt logs, not the cluster average.
A 120 t a month unit moving to a divided blast cupola (estimate)
- Coke now: 180 t a year for 1,440 t of castings, 544 t CO2
- 25% saving: 45 t coke a year, about 136 t CO2 less
- At the profile's coke prices of Rs 11,000 to 20,000 a tonne: Rs 4.95 to 9 lakh a year saved
- Cluster coke: 4,560 t x 3.02 = 13,771 t CO2; electricity 4.1 million kWh x 0.675 = 2,768 t
Quantities and prices from the 2015 cluster profile; the saving is the profile's lower bound. Your own coke bills decide it.
What Senseible does here
The green loan check shows what a lender will ask about your unit; Senseible reads coke bills and electricity bills into monthly figures you can put before and after the change.
Sources: TERI, Cluster profile: Samalkha foundries (2015), BEE, ADEETIE scheme booklet (eligible clusters and technologies), IPCC 2006 Guidelines, Volume 2 Energy (fuel emission factors), CEA, CO2 Baseline Database for the Indian Power Sector (grid factor 0.675 kg CO2 per kWh, FY 2025-26)
Last reviewed 2026-10-31.