Historical Developments of Pyrolysis Reactors: A Review

Abstract

This paper provides a review on pyrolysis technologies, focusing on reactor designs and companies commercializing this technology. The renewed interest on pyrolysis is driven by the potential to convert lignocellulosic materials into bio-oil and biochar and the use of these intermediates for the production bio-fuels, biochemicals and engineered biochars for environmental services. This review presents slow, intermediate, fast and microwave pyrolysis as complementary technologies that share some commonalities in their designs. While slow pyrolysis technologies (traditional carbonization kilns) use wood trunks to produce char chunks for cooking, fast pyrolysis systems process small particles to maximize bio-oil yield. The realization of the environmental issues associated with the use of carbonization technologies and the technical difficulties to operate fast pyrolysis reactors using sand as heating media and large volumes of carrier gas, as well as the problems to refine resulting highly oxygenated oils, are forcing the thermochemical conversion community to rethink the design and use of these reactors. Intermediate pyrolysis reactors (also known as converters) offer opportunities for the large scale balanced production of char and biooil. The capacity of these reactors to process forest and agricultural wastes without much preprocessing is a clear advantage. Microwave pyrolysis is an option for modular small autonomous devises for solid waste management.

Biomass pyrolysis: A review of the process development and challenges from initial researches up to the commercialisation stage

“…A condenser is considered to liquefy the volatiles. The bio-oil and char yields for the products of auger reactor are similar to the fluidised bed reactor yields [251,265] . Auger reactors are divided into four Fig.…”

“…A plan with the capacity of 650 kg/h was built by Ensyn [251,252] . In Canada and USA, circulating fluidised bed reactor was used to produce flavours for food with the capacity of 20 0 0 and 1700 kg/h [251,253] .…”

“…A plan with the capacity of 650 kg/h was built by Ensyn [251,252] . In Canada and USA, circulating fluidised bed reactor was used to produce flavours for food with the capacity of 20 0 0 and 1700 kg/h [251,253] . Recently, companies like Metso, UPM and Fortum developed a circulating fluidised bed reactor with the capacity of 400 kg/h [251] .…”

“…Mainly CNRS laboratories in Nancy, France worked on ablative pyrolysis reactors [260] . The National Renewable Energy Laboratory produced bio-oil with the yield of 60 wt%-65 wt% using an ablative reactor [4,251] . Researchers in Aston University produced bio-oil with the yield of 70 wt%-75 wt% [261] .…”

Recent research progress on bio‐oil conversion into bio‐fuels and raw chemicals: a review

“…The fundamentals of fast pyrolysis and the degree of implementation of different technologies have been summarized in several reviews . The reactors used in continuous operation can be classified as follows: bubbling or circulating fluidized bed, spouted bed, rotary kiln, transported bed, ablative and screw/auger reactors.…”