Context:
IIT Jodhpur’s innovative technology uses algae-assisted fuel cells to capture carbon dioxide, treat wastewater and generate power.
- 1st time that the integration of algae Microbial fuel cells (MFC) with flue gas carbon capture has been attempted anywhere.
Algae-assisted Carbon capture method:
- An indirect method for converting CO2 into carbonates and then use it for algal growth.
- Aim – To generates power, algae biomass and treats water by utilising algae-assisted MFC for flue gas carbon capture.
Flue gas – the gas produced from the flue or chimneys of thermal power stations and other industrial plants.
- Working –
- CO2 from the flue gas is absorbed by the wastewater supplemented with sodium bicarbonate and generates flue-gas-derived bicarbonates (FGDBs).
- FGDB helps in growth of algae Chlorella vulgaris which is thermo-tolerant and can grow in wastewater.
- Algae-assisted MFC is then used to generate electricity.
- Significance –
- More inorganic carbon can stay in the water.
- 1 tonne of algae captures 180 tonnes of flue gas CO2.
- For a cubic meter of wastewater and FGDB in MFC, they got energy of 0.0066 kWhr.
- Limitations – A tonne per day of CO2 capture requires 2 sq. km algae culture area (aerial) in vertically aligned pipes.
Microbial fuel cells (MFC):
- A bio-electrochemical device
- Generates electricity by harnessing the metabolic activity of microorganisms.
- When microorganisms break down organic matter as in wastewater into simpler molecules, electrons are released in the process.
- If these electrons are made to flow through an external circuit, you get electric current.
Source: The Hindu
Previous Year Question
Consider the following activities:
1. Spreading finely ground basalt rock on farmlands extensively
2. Increasing the alkalinity of oceans by adding lime
3. Capturing carbon dioxide released by various industries and pumping it into abandoned subterranean mines in the form of carbonated waters
How many of the above activities are often considered and discussed for carbon capture and sequestration?
[UPSC Civil Services Exam – 2023 Prelims]
(a) Only one
(b) Only two
(c) All three
(d) None
Answer: (c)
