Tidal Current Energy

Chapter 9
Biomass
Pascale Champagne
Department of Civil Engineering, Queen’s University, Kingston,
Ontario, K7L 3N6, Canada
Summary: New biomass is generated at a rate of approximately 224 � 10 9
metric tonnes of dry biomass per annum as a result of photosynthesis on a
global scale. However, biomass currently contributes less than 15% of the
total annual energy use and meets approximately 35% of the energy needs of
developing countries. Biomass feedstocks for alternative energy production
include trees, forestry products, agricultural crops, agricultural residues, animal
wastes, sludges, biosolids, municipal solid waste, marine vegetation and marine
wastes. These biomass feedstocks can be converted to biofuels and bioenergy
through a variety of chemical, biological and thermal conversion processes,
such as enzymatic or acid hydrolysis followed by fermentation and gas/
liquid fermentation, anaerobic digestion, thermal depolymerization, pyrolysis,
gasification, combustion and co-firing. Heat, power, bioethanol, biodiesel and
fuel-cell hydrogen can be produced from these processes. The use of biomass,
particularly the use of organic waste materials as feedstocks, presents significant
benefits, including reduced strain on non-renewable resources, lower greenhouse
gas emissions, decreased landfilling and land application waste management
practices, and economic growth in rural communities and developing countries.
In many cases there remain significant economic, technological and knowledge
challenges and barriers that must be overcome before these chemical, thermal
and biological processes can be implemented on a large scale worldwide.
1. Introduction
Biomass is a sustainable organic matter feedstock, derived in recent times, directly
or indirectly, from plants as a result of photosynthesis. It includes a variety of
materials such as forestry and agricultural residues, organic waste by-products,
energy crops, sewage sludges and biosolids, woody plants and municipal green
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