EVALUATING ANAEROBIC DIGESTION PROJECTSamericanbiogascouncil.org/biocycleWorkshop/mcDonald.pdf · AND DIGESTATEAND DIGESTATE • Biogas -> Electricity + District Heat + Wood Drying

EVALUATINGEVALUATING ANAEROBIC DIGESTION

PROJECTSPROJECTS

Norma McDonaldNorma McDonald

DESIGN AND CONSTRUCTION OF AD PLANTS34 FULL-SCALE PLANTS ON:34 FULL-SCALE PLANTS ON:

- FOOD/BIOWASTE: 14 DRANCO PLANTS (S/U 1992)14 DRANCO PLANTS (S/U 1992)

- RESIDUAL/MIXED WASTE: 10 DRANCO PLANTS (S/U 1997)( )

- ENERGY CROPS: 1 DRANCO-FARM PLANT (S/U 2006)

- ENERGY CROPS/FOOD WASTE/MANURE: 9 WET ADWASTE/MANURE: 9 WET AD PLANTS (S/U 2005)

Five sites under constructionFive sites under construction

2

INNOVATORS IN USE OF BIOGAS, ENERGY AND DIGESTATEAND DIGESTATE

• Biogas -> Electricity + District Heat + Wood Drying D Ch T Hi h T l A i lt+ Dog Chew Toys + High Tunnel Agriculture

• First interconnected biogas plant in many locationsFi t US d i bi t i li i ti (75• First US dairy biogas to pipeline insertion (75 scfm)

• First Quad Generation Biogas Plant• First Quad-Generation Biogas Plant • First US dairy biogas to RCNG (775 GDE/day)• World’s largest AD biogas to RNG (at the time)• World s largest AD biogas to RNG (at the time)• Digestate -> Bedding -> Compost -> Fertilizer

Pellets -> RDF fuelPellets > RDF fuel

SUCCESS STORIESSUCC SS S O S

• Reference plants in 14 different countries, treating source-separated and mixed-household waste, industrial and commercial waste organics, as well as energy crops. • “Senior” plant has demonstrated 99.59349% in-service, active digestion time over the last 20 years!active digestion time over the last 20 years!• Managed/advised >150 plants we did not build

TECHNICAL MERITFEEDSTOCKS EQUIPMENT• FEEDSTOCKS– QUANTITY– QUALITY

CONSISTENCY/

• EQUIPMENT– INSTALLATION– OPERATIONS/

MAINTENANCE– CONSISTENCY/ SEASONALITY

– SECURITY/CONTROL

MAINTENANCE

• VENDORS/SUPPLIERSRELEVANT EXPERIENCE

• PROCESS– FLEXIBILITY– COMPLEXITY

– RELEVANT EXPERIENCE– EXPERIENCED

PERSONNEL ON YOUR PROJECTCOMPLEXITY

– RELIABILITY

• SITE

– ABILITY TO BACK PERFORMANCE WARRANTY, REMAIN IN BUSINESSSITE

– FOOTPRINT RESTRICTIONS

– HEIGHT RESTRICTIONS – REGULATORY/PERMITS– INTERCONNECTION

ECONOMIC MERITCOSTS AMOUNT BENEFITS• COSTS – AMOUNT AND PREDICTABILITY

• BENEFITS -AMOUNT AND PREDICTABILITY

– FEEDSTOCK COST– PROCESSING COST

– PRODUCTIVITY– ON-SITE SAVINGS

– SITE ACQUISITION/ PREPARATION

– PERMITTING

ON SITE SAVINGS– OFF-SITE

REVENUESPERMITTING PROCESS

– EQUIPMENT • INITIAL PURCHASE

• FUNDING SOURCES

AMOUNT AVAILABLEINITIAL PURCHASE• REPAIRS• REPLACEMENT

– GRANTS

– AMOUNT AVAILABLE– CONDITIONS– FINANCING COSTGRANTS

DEFINITION OF SUCCESSFUL PROJECT

• Project works • ProjectProject works technically most of the time

Project technologyadapts toof the time,

within narrow process window

adapts to changing conditionsprocess window

• Can make payments/cover

co d t o s• Market ROR• Lower ratespayments/cover

costs• Lower rates

for community

COMPOSITION OF INCOMING WASTEWELL UNDERSTOOD

MADISON, WISCONSIN SSOWSSOW

Distribution of sorted waste (fresh weight): inner ring: 1st sample outer ring: 2nd

samplesample

KEY ELEMENTS OF SUCCESSFUL PROJECTS

• High Feedstock Security and Predictability– Which is more important?

• Cost/tipping fee per tonpp g p• Quantity per week or year• Composition• Composition

Complete Mix Digester - 3-20% dry matter

DRANCO – 35-55% dry matterOWS, n.vAPPROPRIATE DIGESTER DESIGN

Scenic View Dairy, Fennville, MI. Photo courtesy of Phase 3 Renewables

Horizontal plug flow – 15-30% dry matterOWS, n.v

FACTOR WET DIGESTION BATCH TUNNEL DRY CONTINUOUS

PARTICLE SIZE

PUMPING COMPACTION PUMPINGSIZE

MIXING, FLOATING, SETTLING

POROSITY, PERCOLATION

RATE OF DIGESTION

RATE OF DIGESTION ZONES WITHIN PILE

DEWATERING  RATE OF DIGESTION

LIGHT FRACTION

FLOATING LAYER PERCOLATION, POROSITY

BIOGAS/TON

BIOGAS/TON BIOGAS/TON

HEAVY FRACTION

SEDIMENTATION COMPACTION, PERCOLATION

BIOGAS/TONFRACTION PERCOLATION

BIOGAS/TON BIOGAS/TON

SOLIDS CONTENT

8‐13% 45% ‐ 55% 25% ‐ 50%

KEY ELEMENTS OF SUCCESSFUL PROJECTS

T h l d E i t P id• Technology and Equipment Provider Remains a Positive Factor– On time, on budget– Sufficient support for startup, performance

t t i titest, ongoing operations– Quickly addresses issues or new conditions– Financial strength to back warranties

Why have projects failed –t h i ll i ll b th?technically, economically or both?

• DESIGN-RELATED:– INAPPROPRIATE DESIGN– FLAWED DESIGN

FEEDSTOCK RELATED• FEEDSTOCK-RELATED– QUANTITY SHRINKS– CHARACTERISTICS CHANGE (impacting material handling,

energy potential)

• MANAGEMENT-RELATED– INSUFFICIENT FUNDS– INSUFFICIENT FUNDS– IMPROPER OPERATION– INSUFFICIENT MAINTENANCE

INADEQUATE SITE PLANNING

PUMPAGIT

PUMP

BARNS

DIGESTER

GENSET/BOILERCONTROLS

SITE PLANNING-Location of existing

and proposed PUMP

FLARE

facilities, energy use-Determine process

flow and footprint

STORAGE-DISTANCE-ELEVATION p-PRESSURE DROP-GPM/GPD NEEDSSOIL BEARING-SOIL BEARING

-MONITORING- STORAGE

REDUNDANCY-REDUNDANCY-UTILITY INFRASTRUCTURE

COMPOSITION OF INCOMING WASTE CHANGES DESIGN DOES NOTCHANGES, DESIGN DOES NOT

CATESTROPHIC EVENTS

Flame Flame Arrestor

Flame Arrestor

Flame Trap with

Flame Arrestor Flame

Arrestor

with Thermal Shut-OffFlame Trap

with ThermalThermal Shut-Off Waste Gas

Burner or Flare

Flame

Flame Trap with Thermal Shut-Off

Flame Check

TROUBLES COME NOT AS SINGLE SPIES, BUT IN BATTALLIONS - ShakespeareIN BATTALLIONS Shakespeare

“All it took is 5 years and $150,000,000 from 215 shareholders to see y , ,(EPGRQ.PK) going bust. The reason is very simple - debt. If you think that Crude Oil will reach over $144 a barrel in a short time then their financials will get better (margins increase) and it can change everything but as you see at current oil prices they can't turn a profit $46 5M in debt with $4 7Msee at current oil prices they can t turn a profit - $46.5M in debt with $4.7M in yearly revenues.”

DEFINITION OF SUCCESSFUL PROJECT

• Project works • ProjectProject works technically most of the time

Project technologyadapts toof the time,

within narrow process window

adapts to changing conditionsprocess window

• Can make payments/cover

co d t o s• Market ROR• Lower ratespayments/cover

costs• Lower rates

for community

RECOMMENDATIONSRECOMMENDATIONS

• Run risk-adjusted pro-formasRun risk adjusted pro formas• Run failure mode analysis early in

engineering processengineering process• Obtain reasonable assurances• Place appropriate value on track record

THANK YOU!

QUESTIONS?

Norma McDonald