Biomass by ewghwehws

VIEWS: 45 PAGES: 15

									   Biomass
Samantha Fisher, Emily Noyd,
 and Mariam Hovhannisyan
             What is Biomass?
• The energy comes from the sun, so as long as biomass
  is produced and extracted sustainably—with only as
  much used as is grown—the battery will last indefinitely
• Biomass is any organic matter that can be converted to
  use as an energy source
• Until the 19th century, wood gave Americans 90% of
  the energy used in the country.
• Today biomass provides about 3.3% of our energy.
• Industrial utilities and homes are the biggest users of
  biomass
              Biomass Cont.

• Burning is not the only way to convert
  biomass into usable energy
  – Fermentation produces alcohols (ethanol)
     • From various plants and waste products
  – Conversion
     • Biomass can be converted into gas or liquid fuels
       by using chemicals or heat
  – Bacterial Decay
     • Bacteria feed on dead organisms and produce
       methane
                 Abundance

• Regions holding crop and
  pasture land with “medium to
  high conversion potential”
  are recognized as productive
  regions for biomass.
• Switchgrass (grass crop)
  and Poplar (wood crop) are
  produced in high yields by
  these regions.
                        Distribution
• Ethanol production comes
  in many forms:
  – Manure (Southern regions)
     • Feedlots across the country
       produce billions of pounds of
       manure each year
  – Wood-waste
     • By-products (such as wood
       chips) from wood processing
  – Corn and crop remnants
    (Mid-west)
     • Crop production on a huge
       commercial scale and crop
       waste products after
       harvesting
      Extraction- Environment
• POSITIVE
  – Essentially carbon-neutral
  – Very few pesticides or fertilizers are used.
  – Reduces CO2 emissions by 90% compared to fossil
    fuels
• NEGATIVE
  – Deforestation, soil erosion, desertification, damages
    landscapes, diminishes biodiversity, impoverishes
    human societies dependent on an area’s resources.
    Worse in arid, heavily populated areas.
  – Potentially could lead to a monoculture
  – Causes significant changes in forest vegetation
    structure and species composition in the tree layer
        Extraction- Workers
• Already supports
  66,000 jobs in the
  US, but it could end
  up supporting 3
  times as many jobs
  in the near future.
             Extraction- Animals
• Mild human diversity can boost biodiversity, but intensive
  disturbances (like the extraction of biomass) can harm
  biodiversity.
• Sariska Tiger Reserve- India
   – 10 sites underwent biomass extraction
   – Bird species’ diversity declined, but the number of birds
     remained the same
   – Bird community composition effected by extraction on
     vegetation structure, canopy cover, tree density, and tree height.
   – More than half of the 48 bird species were affected directly or
     indirectly. 8 of the species were very sensitive to the extraction
     (became the indicators of “affected areas”), and 4 species were
     actually encouraged by the extraction.
          Biomass Production
• Burn biomass in presence of large amounts of air
• POWER PLANTS – combustion heats water> steam>
  turn turbines and generators>electricity
• CO-FIRING – Coal and biomass mixed as energy
  source.
• MICROBES – decomposition>biogases
  (methane)>biogases burned>energy.
• GASIFICATION –biomass vaporized at high temp.
  without oxygen>gaseous mixture>energy
• PYROLYSIS – burned without oxygen>pyrolysis
  oil>burned>electricity
Diagrams!
    Production - Environment
• POSITIVE
  – Renewable
  – Burns waste products that would otherwise have
    produced methane emissions during decomposition
  – Reduces pressure to expand landfills by burning
    waste
• NEGATIVE
  – Burning of biomass emits CO2, and when sources
    are overharvested and replacements not planted, has
    significant effects on environment.
          Production - Workers
• POSITIVE
  – Simple to operate
  – Generates employment
  – Balances trade between US and other countries (reduces
    dependency)
  – Can be converted to several different forms of energy
• NEGATIVE
  – Least expensive type of fuel to burn in power plants BUT
    expensive to collect, harvest and store raw materials. There is
    an extra cost of installing technology to process and recycle
    wastes.
      • Less expensive when local fuel sources and no need for costs with
        transportation.
  – Not getting a significant amount of net energy when taking into
    account energy required for farming and to convert plant matter
    into fuel. (this is true for crop plant fuel sources)
Production – Nearby Residents
• POSITIVE
  – reduces emissions of
    nitrogen oxides and
    sulfur dioxide
     • wood contains no
       appreciable sulfur
       content so burns more
       cleanly
                               Doesn’t this look like it smells revolting?
• NEGATIVE
  – could smell revolting
         Disposal and Storage
• The disposal of waste consists of burning,
  burying or storing the material that is potentially
  hazardous. But, landfills (among other methods)
  are becoming a non-viable option due to stricter
  government regulations, environmental impacts
  and lack of space.
• Using biomass in an unregulated way, such as
  the burning of wood for heat, can result in
  emissions of CO2 into the atmosphere.
  However, the controlled combustion of biomass
  waste products generally has limited waste to
  dispose of.
   Disposal and Storage Cont.
• Essentially, biomass as energy converts waste
  products instead of creates them. One of the
  only side-effects is the possibility of chemical
  pollution due to burning.
• New biotechnology options aim to take waste
  and convert it into useable fuel products that can
  be handled at regular refineries instead of
  specialized ones.
• These “bioconversion” units could be set-up at
  sites of continuous biomass waste. Generally,
  compression of the waste at high temperatures
  converts it into an energy source.

								
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