Within the coal gasification (CG) process, coal is partially oxidised (burned) with pure oxygen to produce syngas: a mixture of carbon monoxide (CO) and hydrogen (H2). Contrary to coal firing there is hardly any production of exhaust gasses in this process, as shown below:
The process can be presented in the (highly simplified!) equation below:
CH + O2 → CO + H2 + char
“coal” oxygen carbon monoxide hydrogen
After this, the generated carbon monoxide (CO) is further processed into carbon dioxide (CO2) using water (H2O), as follows:
CO + H2O → CO2 + H2
carbon monoxide water carbon dioxide hydrogen
Therefore, with this process, even more hydrogen is generated, leading to the following total reaction (again highly simplified):
CH + O2 + H2O → CO2 + 2H2 + char
The generated carbon dioxide (CO2) can be harvested and stored or used for further biobased processing; the generated hydrogen (H2) can be burned to produce electricity.
It is important to understand, that with coal gasification the generated CO2 is harvested as a pure by-product, before the actual burning of the generated hydrogen takes place.
This is the reason why this technology is CO2-free: the first unique sellig point of this technology; the second unique selling point being that it generates the cheapest blue/turquoise hydrogen possible, thereby leading us slowly though smoothly into a final CO2-free, sustainable and green hydrogen economy.
Since the produced hydrogen is very cheap, it could even be taxed significantly, to subsidise more green hydrogen projects. This way, total hydrogen production, be it blue, turquoise or green, will be stimulated immensely.
Production of water
Even more interesting is the fact that after burning of the produced hydrogen, only pure water is generated as an “exhaust”. Therefore, the technology is much cleaner than any traditional coal firing process.
Moreover, since more water is generated than initially added to the process (see the last total equation above), there is a net production of pure water.
City with 100,000 inhabitants
With a standard 1,000 MW coal gasification power plant the production of water can easily cover the demand of an eco-friendly city of 100,000 inhabitants.