Biomass and Biofuels

Where do they come from?



The main source is the corn; in the US it is used to produce ethanol which is
then blended with gasoline to make a greener fuel that produces less CO2. After the extraction of ethanol some byproducts were wastes but recent research has found out that those might have energetic properties as well.

Methods of production

Combustion- biomass is burned to produce energy.
Pyrolysis- Biomass materials decompose.
Gasification- turns into gas some parts of the solid biomass.
Digestion and fermentation- Bacteria in power plants convert wastes into gas.

Common Uses


Ethanol
Methanol
Fertilizers
Biogas
Bioethanol
Biobutanol
Biodiesel


Sources-

"Where is biomass energy found?." Centre of Energy. Centre of Energy TM, n.d. Web. 9 Nov 2010. <http://www.centreforenergy.com/AboutEnergy/Biomass/Overview.asp?page=5>.

"How biomass energy works." Clean Energy. Union of conserned scientists, n.d. Web. 9 Nov 2010. <http://www.ucsusa.org/clean_energy/technology_and_impacts/energy_technologies/how-biomass-energy-works.html>.

"Biomass energy – Part Of A Sustainable Future?." Alternate Energy Sources. N.p., n.d. Web. 9 Nov 2010. <http://www.alternate-energy-sources.com/biomass-energy.html>.


Undernutrition, malnutrition and overnutrition.

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Undernutrition, malnutrition and overnutrition


There are several types of nutritional problems and for us to be able to detect them and solve them we should know the differences between them.

  • Undernutrition means that people cannot grow or buy enough energy to meet their basic energy needs.
  • Malnutrition means that people have deficiencies of proteins, calories or other key nutrients
  • Overnutrition occurs when food energy intake exceeds energy use and causes excess of body fat.

Population Pyramids

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Types of  Population Pyramids


In order to understand how population pyramids work we should know they are 3 types of pyramids:
  • Expanding- They have a triangular shape, and they indicate high birth rate, usually due to lack of education and contraceptives and a high death rate due to the lack of medicines and a poor health system. They indicate a poor standard of living.
  • Stable- They have an elipse shape and they indicate a low birth rate due to education and access to contraceptives and a low death rate because of the access to medicines and doctors. They indicate a good standard of living.
  • Contracting- This pyramids usually show the population of a high developed country, this can be seen in the trend of decreasing the birth rate in the country.


Source
http://www.cdli.ca/courses/geog3202/unit06_org03_ilo02/b_activity.html