INNOVATORS OF ZINC - PRODUCING 200M3 WATER PER DAY FROM UNUSED STEAM…

Hydro-I plant at Chanderiya Smelting Complex, commissioned in 2005 generated about 43-45 tonnes of steam from Waste Heat Recovery Boiler which is used to generate power in condensate type turbine of 9.40 MW. During this process, about 25 tonnes of steam gets condensed and remaining 20 tonnes is used for leaching process. Since leaching LP steam requirement is about 35 tonnes, the remaining 15 tonnes steam needs to be taken from CPP.
To reduce the cost of steam from CPP, in 2012 condensate type turbine was replaced by 4.3 MW back pressure type turbines. Due to this, the excess steam of 6-8 tonnes/hr started venting off through final vent. This contributed to water loss of about 150 m3/day.
A team comprising Mr. Deepak Jain - AM, O&M, Mr. Kailash Chandra Choubisa - AM, E&I, Mr. Sunil Dutta - Executive, O&M, Mr. P.C. Kumawat - AM, O&M, Mr. Bhagwan Lal Dhakar - Executive, O&M of Unit-II under guidance of Mr Rajesh Luhadia - Unit Head, Unit-2  brain-stormed for utilization of this vent steam as part of water conservation project.
The team came up with an innovative idea to utilize the available spent heat exchanger to arrest the unutilized 6-8 tonnes of vent steam.
A condensing system was connected before the final vent to convert the excess steam into condensate water and recycled the same into the boiler circuit. Due to additional in-built capacity of condensing system, vent steam of Hydro-2 Roaster could also be condensed with the same system. This lead to water recovery of more than 200m3/day against target of 130m3/day from unused steam.