Industry perspective on biooil production via fast pyrolysis

Abstract

After 40 years of research and limited commercialization, the time has come to accept that biooil from biomass is simply not going to make a significant dent in the renewable fuel spectrum. In 2022, there were 2700 publications on pyrolysis, but only one new plant has been constructed, and while several are on the books, many of those plants have not yet been started. There is lots of hype, but not much action. The pathways to biooil production have been well researched and documented. Apart from some possible optimization, there is little room for wholesale improvements in the technology. In the past, studies promoted economies of scale with large plants processing hundreds of tonnes per day into biooil. These plants are large fixed installations requiring years to construct and commission. The return on investment is simply not there for large systems.Gasification of biooil offers a pathway to produce syngas that can be separated into its components. Smaller and modular fast pyrolysis facilities are recommended. These plants would be located close to the biomass source. Pyrolysis plants are actually low temperature gasification systems where the volatile matter in the biomass is effectively distilled out of the biomass, leaving a carbon-rich biochar as a valuable by-product. Rather than cooling and condensing the vapors into biooil only to reheat, atomize, and gasify at some central facility, the option is to gasify on site at the time of pyrolysis, compress, and ship a compressed product to a central facility where the gas can be separated into components. The downside of this option is there is only 5% by weight of hydrogen in the syngas and that may not be enough to drive the economis.This is an industry perspective paper, and the details of a shift away from biooil to gasification have not been fully developed. The objective of this paper is to stimulate conversation on this topic and start thinking outside the box to come up with novel solutions that are technically and economically sound.