Coal will remain the key fuel for electricity generation in the near future, despite its major contribution to the greenhouse effect. That was the key takeaway from the 38th International Technical Conference on Clean Coal and Fuel Systems, which concluded recently in Clearwater, Florida, U.S.A. A large focus of the event was to provide information about the cleaner use of coal now and in the future.
That message was expected, given that there has been a concentrated effort by many researchers and engineers to make energy from coal as clean as possible. It was interesting to hear one of the speakers directly couple the economic growth of a country with its use of coal.
The five-day conference provided comprehensive and up-to-date information on emerging, evolving and innovative technologies, fuels and policies in the power generation industry. Information and discussions during the conference help industrialists, academicians, researchers, and technology and equipment suppliers to plan their strategies for cleaner use of coal to mitigate environmental concerns in the 21st century.
Panels and technical sessions included discussions on the collection of clean coal technologies (CCTs) like chemical washing, gasification, oxy-fuel combustion, carbon capture sequestration, biomass co-firing, super- and-ultra critical pulverized coal combustion boilers, chemical looping, etc.
This was my second time attending this conference, and I got a lot out of it. In my view, gasification and biomass combustion were the top two topics of discussions this year. I sensed that the focus is back on gasification because environmental drivers like carbon capture are creating great opportunities for more gasification-based projects.
The world-wide gasification capacity is expected to double from 2010 to 2016 (from ~60,000 to ~120,000 MWth of syngas). This is because gasification is one of the most mature clean-coal technologies, and the net pollutant (in this case, mainly carbon dioxide) released from an integrated gasification combined cycle (IGCC) plant is easy to sequestrate, as it is usually in the compressed state.
For the uninitiated, this is how it works. Gasification is a process of partial oxidation of fuel to produce synthetic gas (known as syngas), which is composed primarily of carbon monoxide and hydrogen. Syngas coming out of gasifiers can be transported and burned to produce energy in a cleaner way, as in IGCC plant. It can be also used to produce gasoline, diesel or jet fuel through methanol synthesis or the Fischer–Tropsch conversion process.
I presented our technical paper on computational fluid dynamics (CFD) validations for entrained flow coal gasification. Entrained flow coal gasifiers operate with lower volume fractions of pulverized coal in a high-pressure environment of oxygen or air (though there are some gasifiers that operate at atmospheric pressure). Other fuels like petroleum coke, biomass, heavy oil, natural gas, etc. are used in gasifiers.Our paper presented comparison of predicted syngas composition and temperature profiles from CFD analysis with measured data for two entrained flow gasifiers, including oxygen blown and air blow configurations. Our predicted results were found to be in very good agreement with measured data.
These types of simulation studies are certainly adding values to developing such devices by providing insights on effect of operating conditions or parameters on the performance of the equipment. The end result is that engineers can develop cleaner and more cost-effective designs. I left the conference with a satisfied feeling that, thanks to power of simulation, I could contribute my part for a cleaner tomorrow.