Reducing SOx, NOx, and Hg from Flue Gas



Challenge Summary

To reduce SOx, NOx, and Hg by biotreatment of flue gas by using Microalgae which is a promising bioremediation and biodegradation agent used as feedstock for biofuel production and other bio-based chemicals.

Challenge Scenario

Hindustan Zinc Limited operates the Captive Power Plant (CPP) for its own energy consumption which produces 500 MW of power required for running their smelters. The CPP's because of fossil fuel burning activities generate a huge amount of flue gas (exhaust gas) which comprises of harmful gases such as SOx, NOx, and Hg. The flue gas has negative effects on the environment such as atmospheric pollution, acid rain, and a series of health problems because of this, the central pollution board under their new norms has capped the NOx emissions at 900 mg/Nm3, SOx emissions at 3000 mg/Nm3, and Hg emissions at 0.03 mg/Nm3.

Profile of the End-User

- Compliance Team
- Existing System
Currently, Flue-gas desulfurization (FGD) is widely used for Flue gas treatment which contributes to environmental pollution and also leads to excessing landfilling.

Functional Requirements of the End-User

  • To reduce SOx, NOx, and Hg present in the Flue gas before releasing it into the atmosphere.

Functional & Operational Capabilities

  • To limit emissions at SOx - 3000 mg/Nm3, NOx - 900 mg/Nm3, and Hg 0.03 mg/Nm3.

Operational constraints

  • Easily retrofittable into existing equipment and should have less/easy maintenance.

Expected Tangible Benefits and Measurable Gains

  • Microalgal biomass formed to be used as suitable feedstock to produce biofuels and other bio-based chemicals.

Performance Metrics or Outcomes

  • Reduce any Capital Expenditure with no upfront investment cost
  • Enhance Safety with Ease of Operation

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