WOOD-TO-CHARCOAL CONVERSION IN A PARTIAL-COMBUSTION KILN - AN EXPERIMENTAL-STUDY TO UNDERSTAND AND UPGRADE THE PROCESS

Commercial partial-combustion kilns (PCK) used in carbonization yield a mass efficiency of 15-30% (based on initial wet mass). The present process control of these kilns is tedious, subjective and difficult to generalize. The low yields not only accelerate deforestation but cause atmospheric pollution through smoke. This paper reports the findings of experimental research on a pilot PCK. The weight loss during carbonization, smoke characteristics (flow rate, temperature and chemical composition) and kiln temperatures were investigated to find a process parameter. Weight loss and smoke temperature (when kiln and chimney are insulated) can yield useful process parameters. Oxidation of the carbonization smoke is important in production of charcoal by PCK

Technical and Environmental Performances of Wood Combustion in Domestic Turbo Boilers: Influence of Operating Parameters

International audienc

Les bio-ultracarbofluides (melanges charbon de bois/fuel/eau) CADET/U.T.C./C.T.F.T./CEEMAT

SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : RP 400 (1697) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Local pesticide use intensity conditions landscape effects on biological pest control

International audienceComplex landscapes including semi-natural habitats are expected to favour natural enemies thereby enhancing natural pest biocontrol in crops. However, when considering a large number of situations, the response of natural biocontrol to landscape properties is globally inconsistent, a possible explanation being that local agricultural practices counteract landscape effects. In this study, along a crossed gradient of pesticide use intensity and landscape simplification, we analysed the interactive effects of landscape characteristics and local pesticide use intensity on natural biocontrol. During 3 years, using a set of sentinel prey (weed seeds, aphids and Lepidoptera eggs), biocontrol was estimated in 80 commercial fields located in four contrasted regions in France. For all types of prey excepted weed seeds, the predation rate was influenced by interactions between landscape characteristics and local pesticide use intensity. Proportion of meadow and length of interface between woods and crops had a positive effect on biocontrol of aphids where local pesticide use intensity was low but had a negative effect elsewhere. Moreover, the landscape proportion of suitable habitats for crop pests decreased the predation of sentinel prey, irrespectively of the local pesticide use intensity for weed seeds, but only in fields with low pesticide use for Lepidoptera eggs. These results show that high local pesticide use can counteract the positive expected effects of semi-natural habitats, but also that the necessary pesticide use reduction should be associated with semi-natural habitat enhancement to guarantee an effective natural biocontrol