Preparation of wood for energy use
This paper presents an overview & current sources and forms of raw .materials for wood energy use and the types of machines available to convert them to the desired form for boiler fuel. Both the fuel source or raw material, and the combustion furnace will dictate the requirements for the processing system. Because of the wide range of processing equipment available, systems can be designed to meet most wo6d burning boiler requirements.
Interfacing Forest Engineering with Bioenergy Production
Woody biomass from forestland, urban greenbelts, and residential areas has the potential to provide more than 150 million tons per year of cellulosic feedstocks for biorefineries, pellet fuels, and fermentation. Production sites range from urban lots to large wildland forest tracts. Destinations range from small urban boutiques to large remote industrial complexes. The systems, logistics and equipment will need to be matched to the context of each combination of source and destination. This paper offers a discussion and postulates an operational context for planning equipment, business models, and logistics systems that may represent the likely evolution of the woody biomass feedstock industry. The context includes thousands of very small producers and users, and a continuum toward a few very large industrial complexes. Forest engineers are the logical engineering professionals to expanding their practices to include urban sources and new woody biomass uses. A premise is that forest engineers are well equipped to address issues of materials collection, handling, preprocessing into commercially valuable feedstocks, and transportation systems to move large volumes of woody biomass to market.
Mechanical behaviour and durability of high volume fly ash cementitious composites
The purpose of this research is to separate different morphological particles of ASTM class F fly ash, and study their effect on mechanical behaviour and durability of high volume cementitious mixtures. In this research wet separation of raw fly ash is carried out, which resulted in three layers of different morphological particles. The first layer of particles float, comprise of about 1-5% of fly ash, is identified as cenospheres or hollow spheres. The second layer of particles is measured to be 55-60% of raw fly ash and consisting of porous spherical and rounded particles rich in Si and Al. The third layer particles is measured to be about 35-40% of raw fly ash. High volume fly ash cementitious composites containing second or third layer particles are tested under compression and bending, highlighting a higher strength and ductility in comparison to cementitious ones containing raw fly ash particles. KEYWORDS. Cementitious matrix; Raw fly ash; Second layer particles; Third layer particles.