Ammonia: Advantages and Challenges
Context:
In a recent event in Chennai, a serious Ammonia gas leak from an underwater supply pipeline to a fertilizer plant creates terror and tension amongst citizens.
Relevance:
GS-03 (Mobilization of resources)
What is Ammonia?
- Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the formula NH3.
- It is a colourless gas with a distinct pungent smell.
- Biologically, it is a common nitrogenous waste, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers.
- Because of the chemical inertness of nitrogen gas, production of ammonia from atmospheric nitrogen is difficult. Biological nitrogen fixation is only performed by a few families of microorganisms, the diazotrophs.
- The Haber process that enabled industrial production was invented at the beginning of the 20th century, revolutionizing agriculture.
Uses of Ammonia:
- Around 70% of ammonia produced industrially is used to make fertilisers in various forms and composition, such as urea and diammonium phosphate.
- Ammonia in pure form is also applied directly into the soil.
- It is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products.
Ammonia as a Fuel:
- High Energy Density: Ammonia boasts a high energy density, making it suitable for long-term applications. With nine times the energy density of lithium-ion batteries and three times that of compressed hydrogen, it offers efficient energy storage.
- Low Carbon Emissions: Ammonia has the potential for near-zero carbon dioxide (CO2) emissions during combustion. As an environmentally friendly choice, it stands out compared to traditional fossil fuels.
Challenges Associated with Ammonia as a Fuel:
- Environmental Impact: Despite the promise of low CO2 emissions, current ammonia engines emit pollutants, including unburned ammonia and Nitrogen oxides (NOx), posing risks to the environment and health. Nitrogen in the atmosphere can lead to tropospheric ozone, respiratory issues, and acid rain.
- Production Challenges: Ammonia production relies on energy-intensive processes like the Haber-Bosch method, often using fossil fuels. Green ammonia production, utilizing renewable energy and sustainable hydrogen, faces developmental challenges related to cost and scalability.
Additional Considerations:
- Bridge Fuel: Serving as a bridge fuel, ammonia aids in reducing reliance on conventional fossil fuels. Its use contributes to diversifying the energy mix, enhancing energy security by reducing dependence on a single source.
- Toxicity and Safety: Ammonia’s high toxicity poses risks to human health and the environment if not handled with care. Accidents or mishandling could result in severe consequences due to its corrosiveness.
- Fuel Quality Standards: Establishing consistent quality standards for ammonia proves complex, especially considering variations in production sources and impurity levels.
