BIOMASS ENERGY. Biomass consists of all living plant matter as well as organic wastes derived from plants, humans, marine life, and animals.
Biomass consists of all living plant matter as well as organic wastes derived from plants, humans, marine life, and animals.
In addition trees, grasses, animal dung, as well as sewage, garbage wood construction residues and other components of municipal waste are all examples of biomass
Biomass energy is the first form of energy exploited by man. Biomass is the natural energy for conversion of solar energy to high-energy content products that can be stored transported, and used conveniently.
The main source of biomass energy is from the sun. Plants grow by the process of photosynthesis in which sunlight transforms two abundant raw materials, water and carbondioxide, to carbohydrates and other complex organic compounds of great natural and commercial value. The reaction is shown below:
The process is intermediate in the formation of glucose/sucrose, cellulose polymers, fuel for plant respiration, or variety of other compounds depicted in the figure below:
Since biomass is considered as a renewable there is the need to estimate how rapidly it is regenerated in quantities that are useful to humans.
Semi quantitative measure of the rate of regeneration was proposed by Paul Weisz (1978)
His idea compared the time for regeneration of commercially meaningful quantity of the resource quantity of the resource under scrutiny, Tr to a time at which the resource will be beneficial to mankind Tu
Table 10.1 Selected Dimensionless Time Constant Related to the Renewability of Biomass
EXAMPLE OF US INSTALLED CAPACITY
– 18-24% (14,000-19,000 Btu/kWh)
– $0.065 – 0.08/kWh
– Oxygen = 30-45 wt % dry basis
Bioconversion or biochemical processing refers to the direct or adaptive use of the chemistry of living things to transform one substance to another eg. Fermentation
~ 50%vol CH4, 50%vol CO2
– Animal, Human Wastes
– Sewage Sludge
– Crop Residues
– Environmental Neutralization of Waste
– Fertilizer From Waste
– Household 11.6
– Village 5.8
– Industrial 0.7-1.1
Bacteria that promote fermentation and CORN FEEDSTOCK
acetic acid fermentation
SHORT CHAIN ACIDS
ALCOHOLS, H2 etc.
CH4 CO2 MINERAL AND
Bacteria that promote methane formationOVERALL PROCESS CHEMISTRY FOR PRODUCTION OF BISGAS BY ANAEROBIC DIGESTION OF WET BIOMASS
– Liquid Hydrocarbon Fuels–Chemicals
– Other High Value Products