Attainment of the theoretical yield of carbon from biomass

Citation
Mj. Antal et al., Attainment of the theoretical yield of carbon from biomass, IND ENG RES, 39(11), 2000, pp. 4024-4031
Citations number
28
Categorie Soggetti
Chemical Engineering
Journal title
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
ISSN journal
08885885 → ACNP
Volume
39
Issue
11
Year of publication
2000
Pages
4024 - 4031
Database
ISI
SICI code
0888-5885(200011)39:11<4024:AOTTYO>2.0.ZU;2-8
Abstract
Previous work has shown that very high yields of charcoal are obtained when pyrolysis of the biomass feedstock is conducted at elevated pressure in a closed vessel, wherein the pyrolytic vapors are held captive and in contact with the solid products of pyrolysis. In this paper, we show that, for som e biomass species, the yield of carbon produced by this process effectively attains the theoretical value predicted to exist when thermochemical equil ibrium is realized. Various agricultural wastes (e.g., kukui nut, macadamia nut, and pecan shells) and tropical species (e.g., eucalyptus, leucaena, a nd bamboo) offer higher yields of carbon than the hardwoods traditionally e mployed by industry in the U.S. and Europe. Moreover, the yields of carbon from oat and rice hulls and from sunflower seed hulls are nearly as high as the yields of carbon from hardwoods. There is a correlation between the yi eld of carbon and the acid-insoluble lignin content of the feed. Charcoal b riquettes made from agricultural wastes and lump charcoal from tropical spe cies are promising sources of renewable carbon for use in the smelting of m etal ores.