Researchers from IIT Guwahati have developed an innovative biological process that uses naturally occurring bacteria to remove lead from acidic industrial wastewater, offering a sustainable solution to industrial pollution.

Lead contamination from industries such as battery recycling, mining, smelting, and metallurgy poses serious environmental and public health risks. The new technology provides an eco-friendly alternative to conventional chemical treatment methods.

Key Highlights

• The research was led by Prof. Pranab Kumar Ghosh of the Department of Civil Engineering, IIT Guwahati, along with research scholar Sreekanth Yadav Golla.
• The process uses sulphate-reducing bacteria, naturally occurring microorganisms that thrive in oxygen-free environments.
• The bacteria convert sulphate present in wastewater into sulphide, which reacts with dissolved lead to form lead sulphide, a stable solid mineral that can be easily removed.
• The process also reduces the acidity of wastewater, creating favourable conditions for bacterial growth and improving treatment efficiency.
• The researchers developed a gradual acclimatisation technique that enables the bacteria to survive in highly acidic and lead-contaminated wastewater.

Significance of this Innovation 

• It provides an environmentally friendly and cost-effective method for treating industrial wastewater.
• It reduces toxic lead pollution, protecting human health and ecosystems.
• It converts hazardous dissolved lead into stable lead sulphide, reducing the risk of environmental contamination.
• The treated biosludge was found to release lead well below regulatory limits, making it suitable for safe disposal in engineered municipal landfills.
• The technology can be applied to wastewater generated by battery recycling, mining, smelting, and metallurgical industries.

Health Impact of Lead

• Lead is a highly toxic heavy metal.
• According to the World Health Organization, lead exposure can damage the brain, nervous system, and kidneys, particularly affecting children’s cognitive development.

Future Scope

• The research team plans to improve economic viability by using low-cost carbon sources, reducing sulphide in treated water, and exploring metal recovery from wastewater.
• The findings have been published in the Journal of Environmental Chemical Engineering.

Exam Hook (Prelims)

1. Consider the following statements regarding the biological wastewater treatment developed by IIT Guwahati:

1. It uses sulphate-reducing bacteria to remove dissolved lead from wastewater.
2. The process converts dissolved lead into stable lead sulphide.
3. The technology is suitable only for battery recycling industries.

Which of the statements given above are correct?

(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

One-Line Wrap

IIT Guwahati’s new bacterial treatment offers a sustainable solution for removing toxic lead from industrial wastewater while reducing environmental and public health risks.