BIOGAS 101: On-Farm Anaerobic Digestion

1
(No Transcript)
2
Patrick A. Topper Robert E. Graves Agricultural
and Biological Engineering
3
BIOGAS 101 On-Farm Anaerobic Digestion (AD)

• This presentation is an introductory
  informational tool on biomass renewable energy
  with emphasis on Biogas.
• Comments on how this material can be made more
  useful for extension education are appreciated.

4
Whats Biogas?
Its a gaseous Biofuel made up of a mixture of
methane (60) and carbon dioxide (40) with
trace amounts of hydrogen sulfide and water vapor
(contaminants).
What Biogas is NOT Biogas is NOT pure methane
(natural gas). Biogas is NOT biodiesel. Biogas
is NOT bioethanol.
5
Compare Fuel BTU Values
GASES Biogas Impure expensive to compress
and very expensive to liquefy 600 BTU/ft3
or 80.2 BTU/gal. (vol.) _at_ atmospheric pressure
Methane Higher energy content than biogas
(no CO2) expensive to compress and very
expensive to liquefy 1031 BTU/ ft3 or 137.8
BTU/gal. (vol.) _at_ atmospheric pressure Gaseous
Propane (LP Gas) 2570 BTU/ft3 or 343.6
BTU/gal. (vol.) _at_ atmospheric pressure
LIQUIDS Liquefied Propane (LP Gas)
Concentrated, high energy liquid fuel 91,600
BTU/gal. Petroleum Gasoline High energy,
compact liquid fuel 124,000 BTU/gal. 1 Diesel
Fuel High energy, compact liquid fuel 136,000
BTU/gal.
6
THE BOTTOM LINE Biogas is low in BTUs/gal.
(vol.), so it isnt feasible to use as a motor
fuel. It needs to be used as a stationary
fuel, such as in an electrical power-generating
plant or boiler.
7
How Are Biofuels Produced?

• Anaerobic
• Digestion
• Biogas
• Manure
• Microbes

• Fermentation and
• Distillation
• Bioethanol
• Yeast / Sugar
• Alcohol

• Extraction, Blending,
• and Refining
• Biodiesel
• Refined Diesel Fuel
• Refined Ag-Based Oils

Distiller
Ag- Based Oil(s)
Biogas
Liquid
Refine / Blend
Liquid
Diesel Oil
8
Keep in Mind

• Biogas can be burned and used as a heat source
  (produce hot air, hot water or steam).
• Biogas can be used to operate an engine generator
  set that produces electricity and if the waste
  heat is captured and used, (Combined Heat
  Power-CHP), plant efficiency improves.
• The monetary benefit occurs when the electricity
  generated is used to replace electricity thats
  normally bought at retail.
• A Combined Heat Power (CHP) unit increases the
  cost of an anaerobic digester system.
• You can store gas but cant store electricity.
• PA Net Metering power company must buy
  electricity generated, but you must meet their
  requirements.

9
How Do Anaerobic Digesters (AD) Work?
10
(No Transcript)
11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14
(No Transcript)
15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
Summary

• Biofuels Biogas, Bioethanol, Biodiesel
• Use of Biogas Heat or Electricity
• AD Costs to Consider Design, Materials,
• Temperature, Location, Permits, CHP Unit,
• Grid Interconnection, Extra Management and
  Knowledge
• Feed Stocks Manure and / or Food Waste
• AD is for ODOR REDUCTION OF MANURE !
• The energy is a bonus !

22
(No Transcript)
23
THANK YOU!
With additional project support funding provided
by
24
(No Transcript)