How much petcoke does an auto temperature controller on jigger dyeing machines save?
About 2 t of pet coke a year per jigger, 20 t across ten, in BEE's Pali report. Operators ran dye baths above 96 C when the reactive dyes used need 80 C. A sensor and steam valve cost Rs 12,000 a machine, so payback is about 10 months at 2010 prices.
What the auditors saw
- Steam injection valves opened and closed by eye; every jigger checked ran above 96 C.
- Dyes in Pali are mainly reactive, needing 80 C. Direct, sulphur and disperse dyes need 95 to 100 C.
- A jigger draws about 250 kg of steam an hour while heating; a batch is about 450 m, 50 to 70 kg of cloth.
- Pali has over 5,000 jiggers; the report reckons about 2,000 suit this fix.
The arithmetic for one machine
- 2,400 litres of hot water a day heated 16 C less: 38,400 kcal a day.
- Boiler at 70%, coke at 8,200 kcal a kg: 6.69 kg a day, 2.0 t over 300 days.
- At Rs 7,500 a tonne: Rs 15,052 a year against Rs 12,000 for the controller.
- Ten machines: Rs 1.0 lakh of equipment plus Rs 0.2 lakh fitting, saving Rs 1.51 lakh: 9.6 months. No downtime.
Why the real saving may be larger
The sum counts only heating the water 16 C less. A bath held near boiling also loses more heat to evaporation and from its surface, and the report puts the extra heat used without control at 16%. Weigh coke for a month before and after to see your own figure.
What to specify
- A corrosion-resistant temperature sensor, since it sits in the dye liquor.
- A solenoid steam valve rated for frequent switching; keep a spare.
- A set point per dye class, locked so it cannot be turned up on the shop floor.
Ten jiggers, one year
- Heat saved per machine: 2,400 x 1 x (96 minus 80) = 38,400 kcal a day
- Coke: 38,400 / (8,200 x 0.70) = 6.69 kg a day x 300 = 2.0 t
- Ten machines: 20.1 t x 3.17 = 63.6 t CO2
- The report says 55 t, using a lower factor
Pet coke at the IPCC 2006 default, 3.17 t CO2 a tonne (32.5 GJ a tonne x 97.5 kg CO2 per GJ). An estimate; a lab analysis of your own coke is better.
What Senseible does here
Senseible turns pet coke invoices into monthly tonnes tied to each bill, which is the before and after record for ten controllers. Multiply by the 3.17 above, since it has no pet coke factor of its own.
- Green loan readiness check
- Pet coke emission factor in India
- Pali dyeing unit: boiler CO2
- Pali hand and power process units
- Jet dyeing condensate recovery
Sources: BEE, Detailed project report: auto temperature controller in jigger dyeing machine, Pali textile cluster (2010, SAMEEEKSHA), IPCC 2006 Guidelines, Volume 2 Energy, Tables 1.2 and 2.3
Last reviewed 2026-11-01. Report figures are from a BEE SME programme project report; costs and paybacks are at the report year's prices. Check today's fuel and power prices and a current quote before you rely on the payback.