algae symposium f&b - august 18 - 2009 - 02

Harvesting and Processing Midwestern Algae Commercialization Workshop Minneapolis – August 18th, 2009

Luca Zullo, Ph.D. VerdeNero LLC PO Box 239 Excelsior, MN 55331 [email protected]

VerdeNero LLC - Midwestern Algae Commercialization Workshop Minneapolis, August 18th, 2009

Substantive use of lipids to address world-wide fuel demand has three problems

•  Volume is relatively small

•  Cost is high

– Different elasticity of food and fuel S/D dynamics

•  Potential lousy environmental and social impact

– Food vs. Fuel – Carbon footprint


Algae promise : Large lipids production

Oil yields – Source unknown (somewhere in hyperspace), but widely used table


Reality check! Thermodynamics are not an opinion!

500-3500/5000

Still good, but where, at which cost and what are the challenges


Algae in a nutshell

•  Pros:

–  Address lipids production, one of the most relevant and potentially valuable biofuels feedstock

–  Provide a plausible pathway to solve the environmental and social issues plaguing the large scale deployment of biofuels

–  Are low level organisms which are easier to work than superior plants –  Can deliver extremely high productivity

•  Cons: –  Underdeveloped technology –  Dauntingly complex issues of system integration –  Economics still very uncertain –  Overoptimistic expectations


Algae: the challenges

  Consistent and realistic biomass and lipid yields   Cultivation method/productivity

-  Strain selection -  Lipid content -  Consistent Yield

  Control of ecosystem -  Predators and parasites -  Contamination and toxins -  Containment of genetically modified organisms, if used

  Nutrients (CO2, Nitrogen, Phosphorus, Iron among the most important ones)   Availability of suitable land and water   Temperature and solar irradiation   Harvesting and processing

-  Pumping -  Biomass concentration -  Oil extraction -  Salt removal

  Capital and operating cost -  Process scalability

»  Energy inputs   Co-products marketability and value   Permitting and environmental impact

-  Waste water -  Non native species containment and biosecurity

Biology

System Integration

Engineering

Business and Society Difficulty


Microalgae cultivation. Two approaches.

•  Closed systems - Photobioreactors –  Higher productivity –  Species and contamination control –  Higher cost, capital and operating –  Higher density –  Temperature control in warm climates –  Need for degassing

•  Open systems - Ponds –  Native species –  Water evaporation –  Lower cost –  Higher footprint –  Lower productivity

•  One commonality: desired product is very diluted


Algae are very diluted.

Algae are deceptive because they are very good at pigment production

Even in best conditions (much) less than 1 gram (db) biomass per liter!

Physical and biological processes prevents higher concentrations

Key differences with conventional crops: • Dilution

• Fast growth requires continuous harvesting • Storage is economically not viable

• Nutrient delivery


Productivity in controlled lab conditions of some non-gmo strains

Source: Prof. Mario Tredici University of Florence, Italy

<0.0003% ds


Is this a realistic representation of the future?


No… because, it already exists

Parry Nutraceuticals, Ltd - India

Earthrise Nutritional, CA

Chlorella producer, Japan


Flow process form Earth rise

Source Ahma Belay CTO – Earthrise Nutritional


Basic flow diagram of micro-algae processing

Primary harvesting step

Concentration, may include more than one step. More than 20% ds unlikely without physical disruption of cell wall structure and drying

May require drying to get to oil concentration high enough for oil extraction. May require additional treatment step to disrupt cell wall structure and facilitate separation

Current oil extraction approaches (e.g. solvent extraction) work fine but not optimal for relatively low fat content. We need to reduce the need for drying.


Harvesting and primary processing.

–  Key operational issues   Frequency and quantity of harvesting   Organism adaptation and efficiency   Water recycle and mixing optimization   Mechanical damage to organism and fouling of equipment   Use of brackish water add capital and maintenance costs

–  Existing technologies   Chemical flocculation

-  Cons: chemical cost, affected by salinity and large equipment volume. Pros: simple equipment and relatively low capital cost

  Physical flocculation (e.g. DAF) -  Cons: operating cost and equipment volume. Pros: very effective

  Centrifugation -  Pros: effective and well understood, potentially highest concentration level. Cons: Expensive

(capital and operations)   Filtration

-  Pros: Relatively inexpensive capital cost. Cons: Slow and uncertain operating cost, biological adaptation.

  Hydrocyclones -  Pros: Inexpensive and no moving parts. Cons: less concentration than centrifuges

  Ultrasonics -  Use ultrasonics to concentrate (low power) and after skimming destroy (high power) cells -  Pros: very effective. Cons: Energy and Capital intensive

  Settlers -  Pros: Inexpensive and relatively simple. Cons: very slow, water balance, high volume,

efficiency   Electrostatic separation

-  Pros: Effective. Cons: unproven at any significant scale, cost unknown, may require pH change which will impact cost of water recycle, affected by salinity


An example of a system integration issue

Source Ahma Belay CTO – Earthrise Nutritional


A little exercise to visualize and quantify dilution impact on cost

A regulation Olympic pool 50 m x 25 m x 2 m 2,500,000 liters 661,375 gallons


Now that we know how much water we have….

•  Let’s assume:

–  That the same amount of water in an Olympic pool is used in a raceway pond 50 cm (1.6 ft) deep

  That is a growing area of 5000 m2 or 1.27 ac –  Very good – but not impossible - productivity values

  20 g/m2/day   30% lipids

•  That means: –  100 kg (220 lb) of biomass per day –  33 l (8.7 gal) of oil per day –  2,500 gal/ac of oil yield

In order to produce 8.7 gal of oil we need to process 661,000 gallons of water EVERY DAY


Some back of a small envelope calculation •  Pumping cost for 661,000 gpd

–  Pumping cost ($/hr) = 0.746 * F_gpm * H_ft * P_cost/(3960 * E_p*E_m) –  Assuming:

  $0.07/kWh   10 ft head

–  $1.80/day or $0.20/gal of oil –  Net of capital cost

•  Primary concentration –  661,000 gpd to 1322 gpd –  Ignore costs and energy demand

•  Secondary concentration

–  1322 gpd to 500 gpd –  Centrifugation of 1322 gpd –  500 gpd product (20% ds) –  1/3 to 2/3 hp centrifuge –  $0.07/gal of oil –  Net of capital cost

•  Dewatering

–  500 gpd @ 20% ds –  6% oil content –  Remove enough water to be at 10% oil, 72 gpd –  72 gpd -> 582 lb of water @ 1000 BTU/lb -> 582,000 BTU/day –  Assuming gas at $4/MMBTU –  $2.32/day or $0.26/gal of oil –  Net of capital cost and efficiency factors

In this extremely simplified circumstances already the processing cost is > $0.50/gal

Energy inputs: 256 kWh/day

Energy yield of oil 307 kWh/day

2/3 of oil energy already lost!


Detailed numbers indicate that a <$1.00/gal facility is nowhere insight

Economic Parameters

Desired rate of return 10.00% Depreciation years 10

Analysis Period (years) 20 Tax Rate 40.00%

Capital Recovery Factor 0.117 Present Value

Depreciation 0.614 Fixed Charge Rate 0.148

Algae Pond Operational

Data Pond Depth cm 20

Single Pond Area ha 10 Evaporation Rate cm/day 0.591366243

Area Productivity g/sq m-d 10.93990123 Pond Algae Concentration

g/l 0.38934736 % Lipid Content 15%

Total Pond Area (incr 10 ha) 1,000

Single Pond Flow lpd 2,809,805 Total Pond Flow lpd 280,980,491 Pond volume liters 20,000,000

Retention Time days 7

Other Inputs Electricity Cost $0.07

Power Plant Recov CO2 Cost oper mt $50.46

Natural Gas Price per MMBtu $6.51

Soy meal price per mt $203.38 Land Price per acre $3,000.00 Total to Pond Acres 1.50

Water Price per acre-ft $21.96 Water Price per cu m $0.018

Kadam (1997) cost $40.00 Inflation adjusted $49.46

$2006 Total Biomass Production 1,504,236 Total Oil Production 1,485,428 Total Capital $78,164,222 Total Operating Cost $13,706,821 Capital per Annual Gallon $52.62

Oil (gal) Algae ( mt) Pond (ha) Annualized Capital $7.77 $320 $11,541 Operating Cost $9.23 $380 $13,707 Total Cost $17.00 $699 $25,248 Credit Algae Coprod $2.77 $114 $4,110 Credit Elec $0.00 $0 $0 Net Cost $14.23 $585.49 $21,137

• CO2 from flue gas • Dedicated algae ponds • Primary dewater: belt filter • Secondary dewater: centrifuge • Drying natural gas • Hexane solvent extraction

Basic economics of a facility for 1.5 Mgal/yr


We need to think “out of the proverbial box”

•  Despite the challenges, algae still remain the most promising opportunity for a large scale biofuels feedstock

•  The comparison with land based crops is misleading as it cognitively force us to think in like manner

–  New thinking and approaches are necessary both at the systemic and unit operation level –  We are inventing a new system. Imagine that we want to create the ethanol industry while

inventing corn or sugar cane agriculture , introducing corn feed and sweeteners as new to the world products.

•  Algae is not only biofuels –  Feed products may make the industry viable before fuels. –  Algae based waste water treatment is very promising

•  Admit the challenge and face it rather than ride the hype. Report real number, forecast realistic projection

–  Realize that this is not completely new and much work was done in the last fifty years by very smart people –  Adopt a multidisciplinary approach and join forces –  Learn from failure. Why are so many on the same path to nowhere that lead to GreenFuel $70M fiasco? –  We need to focus where order of magnitude improvement are possible.

•  Extraordinary claims require extraordinary proofs.


Reference: Many ideas are not new. People were working on algae culture more than 50 years ago!

Handbook of Microalgal Culture Biotechnology and Applied Phycology Amos Richmond Ed. Blackwell Publishing, Third Edition 2006 ISBN-10 0-632-05953-2

algae symposium f&b - august 18 - 2009 - 02

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