Methane

Methane

From Coal To Methane with Microbes

[|Ciris Energy]

Anaerobic Digester -Bellingham Technical College

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Michigan State Anaerobic Bio Digester media type="youtube" key="aULRryCVMyY" width="784" height="439" align="center"

5 Categories of Digesters

2. Plug - Flow (First in - First out) - works like a tube of toothpaste
 * 1) CSTR (Complete Stirred Tank Reactor
 * 2) Vertical steel tank- small footprint
 * 3) Found in Europe and waste water facilities
 * 4) Provide very consistent environment for bacteria - therefore they are easy to control except for duration of process
 * Vertical tank design
 * more difficult to completely mix



3. Pack Bed Biofilm Reactor media type="youtube" key="mwFAGs_yQyQ" width="840" height="470" align="center"
 * Packing provides surface area for bacteria
 * Packing can be engineered or shredded plastics or rubber
 * provides higher population of bacteria
 * clogs easy. Especially if wastes are high in fiber

4. Covered Lagoon media type="youtube" key="ozrirkRf4f4" width="672" height="501" align="center"
 * No heat
 * No Mix
 * Must be in warm regions - below the 40th Parallel
 * cheapest

5. UASB (Up Flow Anaerobic Sludge Bed)
 * Sludge comes up from bottom
 * Most industrial waste-water systems use this
 * Bacteria cling together (snowball affect) forming beads
 * Beads (pellets make up the bed
 * enormous bacteria population

[|How Bio Gas Plant Operates]