The demonstration DBC at Howrah

TERI carried out diagnostic study of the foundries in Agra cluster, one of the largest clusters in India. Mounting environmental pressures for the protection of the Taj Mahal, the Supreme Court of India passed a ruling in 1996 that banned coke/coal use in the Taj Trapezium Zone (Agra-Mathura-Ferozabad Trapezium). This lead to the closure of many foundries. Since the use of a fuel other than coal/coke did not seem feasible, the focus of the project was shifted from Agra to Howrah, which is also a large foundry cluster.

Howrah foundry cluster also faced environmental pressure; however, there was no ban on use of coke but it had to conform to the emission standards of SPM (suspended particulate matter) through incorporation of suitable pollution control systems. TERI decided to address both energy and environmental issues through technology demonstration projects.

The improved DBC (divided blast cupola) to enhance energy efficiency and reduce fuel consumption and venturi-scrubber based PCS (pollution control system) to reduce SPM emissions were developed and commissioned at Bharat Engineering Works in 1998. Important partners in this effort were Sorane SA, Cast Metals Development Ltd, and Alstom Projects (then known as ABB). Charge coke savings to the order of 35% were achieved in the DBC, and the PCS delivered a much better performance (SPM – 50 mg/Nm³) than the pollution control board’s stipulated limit (150 mg/Nm³) for the foundries.