Potential use of wood pyrolysis coproducts: A review

Abstract

AbstractThe wood carbonization is made at an enclosed environment with controlled addition of atmospheric air producing, besides charcoal, other coproducts such as condensable and non‐condensable gases. These gases, which represent 70% of the dry wood mass, are released into the atmosphere, decreasing air quality and producing environmental and social impacts. In this context, it is necessary to develop technologies capable to convert these gases into usable products or transform them into heat and power. The incineration of gases from charcoal kilns opens new opportunities of business because the energy provided by burners can be utilized for drying the wood to be introduced into the kilns and for generation of electricity. On the other hand, condensable gases can also be used on a route to recover and purify the pyroligneous acid. Pyroligneous acid finds application in diverse areas, as antiseptic, antioxidant, antimicrobial, anti‐inflammatory, herbicide, pesticide, plant growth enhancer, antitermitic activities; is a source for valuable chemicals; and provides smoked flavor and aroma for food. The main objective of this review is to explore the potential use of wood pyrolysis coproducts, aiming to subsidize and to encourage the technological development of equipment for use of these coproducts. This paper highlights the potential benefits arising from pyroligneous acid application and discusses the charcoal cogeneration technologies.