In News: Ministry of Coal has constituted two Committees, one to oversee the program and another of experts to give guidance to the Ministry. This is aimed for contributing to PM’s agenda of a hydrogen-based economy in a clean manner.
Producing Hydrogen through Coal
Coal is one of the important sources of hydrogen making (Brown Hydrogen) apart from Natural Gas (Grey hydrogen) and renewable energy (Green Hydrogen) through electrolysis. In case of renewable energy (Green Hydrogen) surplus solar power is used to electrolyze water into hydrogen and oxygen.
The global emphasis is on substituting liquid fuels with hydrogen (as fuel in vehicles), storage of surplus renewable power as hydrogen (as power cannot be stored at a cost effective price), and cutting down emission.
However, Coal has not been encouraged elsewhere because of the fear that while extracting hydrogen via coal (from the moisture embedded in coal) there may be carbon emission.
Almost 100% of Hydrogen produced in India is through Natural Gas.
The Challenges
Production of hydrogen from coal will have challenges in terms of high emissions and ‘carbon capture, utilisation and storage’ (CCUS) will play an important role. However, when the carbon monoxide and carbon dioxide formed during coal to hydrogen process are trapped and stored in an environmentally sustainable manner (CCUS), then, Indian coal reserves could become a great source of hydrogen.
For every tonne of brown hydrogen produced, we get – at a minimum – between 10 and 12 tonnes of CO2. That’s not even including the CO2 produced by the energy source driving the process, or the CO2 produced in transporting the hydrogen to the customer. In all, production and transport of brown hydrogen is very bad for the environment.
In steel making, lots of work has been done on production of steel by use of Hydrogen. However, iron reduction through hydrogen is an endothermic reaction and will require lot of heat. This heat can be generated in DRI plants due to presence of CO in syn Gas being produced from coal gasification process.
