Expert Opinion on Municipal Solid Waste Gasification and Pyrolysis

For anyone interested in Municipal Solid Waste gasification and pyrolysis, read the truths reported by  Mr. Hakan Rylander in the following article:

http://wtert.blogspot.co.uk/2012/04/history-of-gasification-of-municipal.html

For a rare occasion amid all the promotional talk of those with financial interests, we have an admittance about the reasons for repeated failures when trying to thermally decompose mixed waste in oxygen limited conditions in practical situations. Apart from the negative energy balance, the insurmountable factor is the heterogeneity of the waste and its varying reaction kinetics. As Mr Rylander says:

“Waste is not a homogenous fuel. It has so far turned out to be too heterogenous to be able to treat in a gasification or pyrolysis process, irrespective of how you pre-treat the waste. It is absolutely not applicable for mixed MSW with today’s technology.”

All over the world these systems are being promoted, because incineration has such a bad press. But as I’ve mentioned previously [1, 2, 3], before considering whether these will ever work, look at whether the technology has ever had one hour of operation, and look at the history of previous system failures. As Mr Rylander goes on to say:

“In the middle 1970-ies [I] participated in a very good conference in Antwerp about waste management. There was a whole session about gasification and pyrolysis and I was full of enthusiasm, expecting a lot from the different presentations. On the way in to the conference room I walked beside an older gentleman and colleague from Germany. I told him about my expectations and he looked very friendly upon me telling me that he had started to work with R&D within waste management already in 1922 at the Batelle Institute in Frankfurt, and the task was to gasify/pyrolyse waste in a better way than could be done in a waste incineration plant. He told me that they without any success had been trying to do so and that he still had very little faith gasification/pyrolysis could be developed and turn out to be a successful technology for waste.”

The Batelle Institute experts should know as this was the height of gasification development, and Batelle were at the forefront.

Gasifiers are a great technology that can give fantastic results for sustainable energy from wood chip. When set up right, as the Swedes and Germans have shown over the last 90 years, they can provide small-scale localised heat and power on demand. People however need to know the truth about what the present technology cannot do before they invest in it or consider passing it for planning permission.