Electronic nose to detect “Hydrogen Sulphide” from Sewers

• Scientists from the Centre for Nano and Soft Matter Sciences (CeNS), Bangalore have developed Electronic Nose to detect Hydrogen Sulphide from swamps and sewers.
• CeNS is an autonomous institute of the Department of Science & Technology

About Hydrogen Sulphide:

• Hydrogen Sulphide is the chemical compound with the formula H2S.
• It is a colourless chalcogen hydride gas. It is with the characteristic foul odour of rotten eggs. (Chacogen –  chalcogens are the chemical elements in group 16 of the periodic table).
• Hydrogen Sulphide is slightly denser than air. It is also poisonous, corrosive and flammable.

How is Hydrogen Sulphide produced?

• Hydrogen sulfide is often produced from the microbial breakdown of organic matter in the absence of oxygen gas, such as in swamps and sewers.
• This process is commonly known as anaerobic digestion.
• It occurs naturally in crude oil, natural gas, and hot springs.
• H2S also occurs in volcanic gases, natural gas and in some sources of well water.
• The human body also produces small amounts of H2S and uses it as a signalling molecule.

Impact of Hydrogen Sulphide on Health:

• The health effects of hydrogen sulphide depend on how much H2S a person inhales and for how long.
• Exposure to Hydrogen Sulphide includes headaches, memory loss, and problems with the cardiovascular system.
• However, many effects are seen even at low concentrations. Effects range from mild, headaches or eye irritation to very serious, unconsciousness and death.

New Delhi Dialogue 2021 on The Hydrogen Economy

The Union Minister inaugurated The Hydrogen Economy – New Delhi Dialogue 2021.

About Hydrogen Economy – New Delhi Dialogue 2021:

• New Delhi Dialogue 2021 is organized by The Energy Forum(TEF), an independent think tank in India in collaboration with the Federation of Indian Petroleum Industry(FIPI).
• FIPI is under the patronage of the Ministry of Petroleum and Natural Gas.
• The dialogue aims to discuss emerging hydrogen ecosystems and exploring opportunities for collaboration, cooperation and coalition.
• The dialogue will comprise a High-level Ministerial Session followed by Panel Discussions by eminent policymakers.
• The dialogue focus on policy roadmaps and mapping the demand and supply of Hydrogen.

About National Hydrogen Energy Mission:

• The Union Budget for 2021-22 announced a National Hydrogen Energy Mission (NHM). The mission will draw a road map for using hydrogen as an energy source.
• The mission will focus on the generation of hydrogen from green power resources.

Hydrogen as a fuel:

• Hydrogen is the lightest element in the periodic table. It is the most abundant chemical substance in the universe.
• However, the most common element in nature is not available freely. Hydrogen also exists only in combination with other elements. Thus, it has to be extracted from natural compounds, like water.
• Hydrogen is categorized by colour tabs, based on its source. We can divide it into ‘grey’ hydrogen (produced from fossil fuels), ‘blue’ hydrogen (produced from fossil fuels with carbon capture and storage) or ‘green’ hydrogen (produced from renewable electricity).
• Green Hydrogen is specifically focussed upon in the government mission.
• Hydrogen is considered an alternative to fossil and other types of fuels.
• However, Hydrogen is a carrier of energy, not a source of it. Fuel cells are required to transform Hydrogen into electricity and use it. Cells use oxidizing agents through an oxidation-reduction reaction, to convert chemical energy into electrical energy.
• In the case of Hydrogen, fuel cells combine Hydrogen and Oxygen to generate electricity.  A catalyst, usually made from platinum is generally used for this.

Advantages of Hydrogen fuel:

• Readily Available: It is a basic earth element and is available in abundance.
• Doesn’t Produce Harmful Emissions: When it burns, it doesn’t emit harmful substances. The only by-product or emission from the usage of hydrogen fuel is water. It makes this fuel 100% clean.
• Environmentally Friendly: It is a non-toxic substance which is rare for a fuel source.
• Fuel-Efficient: Compared to diesel or gas, it is much more fuel-efficient as it can produce more energy per pound of fuel.

Disadvantages of Hydrogen Fuel:

• Expensive: Although it is widely available, it is time-consuming to separate hydrogen gas from its companion substances.
• Difficult to Store: Hydrogen is very difficult to store. Its transportation even in a small amount is very expensive.
• Not Easy to Replace Existing Infrastructure: There is not much infrastructure that can support hydrogen as fuel. Also, cars need to be refitted in order to accommodate hydrogen as fuel.
• Highly Inflammable: Since it is a very powerful source of fuel, hydrogen can be very flammable. Hydrogen gas burns in air at very wide concentrations – between 4% and 75%.