Producing Algal Biofuel for Profit Page 1

Producing Algal Fuel for Profit

Jaw-Kai Wang

CEO, Jawkai Bioengineering R&D Center, Shenzhen, China; Member, National Academy of Engineering (USA)

INTRODUCTION

Among the most promising candidates for the production of biofuel are diatoms. An outstanding attribute

of a diatom-based open biofuel production system is its ability to simultaneously capture carbon dioxide,

and remove nutrients and heavy metal from the waste water while producing biofuel. Fast growing

diatoms can double their weight in a few hours.

An economically competitive open diatom production system must be able to successfully confront two

major problems: 1) How to control contamination by other species; in an open production system invasive

species will come into the system and the ability to maintain the dominance of a selected species in the

system is essential, 2) There are many aquatic microorganisms that feed on microalgae and an open

production system must be able to control these microorganisms. In agriculture, these tasks are often

taken care of by herbicides and pesticides. In the cultivation of aquatic plants, including diatoms,

poisonous chemicals cannot be used, because while they may control the undesirable species and

microorganisms, they will also kill the aquatic plants one wishes to cultivate.

DIATOMS

Diatoms are photosynthetic, eukaryotic microalgae of the Bacillariophyta family. There are more than

200 genera of living diatoms, and it is estimated that there are approximately 100,000 extant species.[1, 2]

Diatoms contain a wide variety of lipids, which include membrane-bound polar lipids and non-polar

lipids that also encompass free fatty acids and fatty acids.[3,4] Compounds such as sterols, waxes, and

acyl lipids have also been identified. Increased lipid concentrations within different species of diatoms

have been observed by modification of nutrient availability and other requisite growth conditions. [5-10]

Syvertsen [11] has concluded that to maximize microalgae fatty acid production, it is best to maximize

total microalgae production. Lipid fractions as high as 70–85% have been reported in some diatoms. High

growth rates of diatoms combined with significant lipid productivities make them a leading candidate

source of biofuels. However, this opportunity has not been explored successfully. [12]

The use of silicon by diatoms is believed by many researchers to be the key to their ecological success.

Egge & Aksnes stated diatom use silicate as regulating nutrient in phytoplankton competition. they found

that diatom dominance occurs regardless of season if silicate concentration exceeded a threshold of 2 µM,

they found that diatoms typically represented more than 70% of the phytoplankton community. [14]

Raven noted that, relative to organic cell walls, silica frustules require less energy to synthesize

(approximately 8% of a comparable organic wall), potentially a significant saving on the overall cell

energy budget. [15] Other researchers have suggested that the biogenic silica in diatom cell walls acts as

an effective pH buffering agent, facilitating the conversion of bicarbonate to dissolved CO2 (which is

more readily assimilated). Notwithstanding the possible advantages conferred by silicon, diatoms

typically have higher growth rates than other algae of a corresponding size. [13, 16]

MITIGATION OF CARBON DIOXIDE AND OTHER POLLUTANT

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Diatom cultures can remove biological NOx from combustion gases.[17] The ability of an open algae

production facility to simultaneously capture carbon dioxide and other pollutants can be very useful in a

symbiotic (power generation)/(diatom production), or (oil refining)/(diatom production),or

(brewery)/(diatom production) relationship. Similarly, the ability to remove nutrients can be used to

advantage in the treatment of waste water.

PRODUCTION AND HARVESTING OF MICROALGAE

The mechanism of photosynthesis in diatoms is similar to that of higher plants, but single cell organisms

are inherently more efficient converters of solar energy due to their simple cellular structure. In addition,

because the cells grow in aqueous suspensions, they enjoy more efficient access to water, carbon dioxide,

and other dissolved nutrients. For these reasons, microalgae are capable of producing up to 30 times the

amount of oil per unit area of land, compared to terrestrial oilseed crops.[18] Weyer, et al calculated the

theoretical maximum for using algal feed stock to be 354,000 liters per hectare per year of unrefined oil

(bio-crude), while the best cases in real world production to be 40,700-53,000 liters per hectare per year

of bio-crude. [19] Against the best real world production estimates made by Weyer, et al we should take

note, as it is shown later in the pages, that, since 2009, in Shenzhen, Jawkai Bioengineering R&D Center

has already achieved a sustained yield of over 36,000 liters of bio-crude per hectare on a 300-day year

basis.

Marine diatoms could also, in fact, be cultivated in the open ocean. [20] For systems that float in water,

the problem of hear removal may be reduced. However, the cost of maintenance will increase.

OPEN SYSTEM PRODUCTION OF MICROALGAE

Aquaculturists have traditionally produced microalgae in closed systems to prevent the inevitable

contamination encountered in open systems. Closed systems have many difficulties, and the more

important ones are the need to remove heat and the overwhelming difficulty in maintenance. Photo-

bioreactors must receive light to operate, and with light comes heat. Solar heat received must be removed

from a closed system, making the system prohibitively expensive, both in terms of cost and energy.

Marine diatoms such as Chaetoceros have been continuously cultivated successfully in a commercial

open production system. [21] The basic pilot plant has been further developed and a patent was issued to

Wang. [22] Kona Bay Oyster & Shrimp company in Kona, Hawaii has built a commercial system and

successfully operated it since the late 1990s producing marine diatom Chaetoceros in an open system.

The diatom produced was used to produce shrimp brood stock and bivalves. Basically, if one can

maintain the Chaetoceros, or any other diatom, in an open system growing at the log phase by controlling,

among other things, the concentration of Si, then it will outgrow non-diatom species and thereby maintain

its dominant position in the production system. [23] The control of aquatic animals that feed on

microalgae has been achieved and a patent is currently pending.

PHOTO-BIOREACTOR

Photo-bioreactors need to be inexpensive in order to meet the stringent cost limitation in biofuel

production. Any container that is made of transparent material of sufficient strength is likely to be overly

expensive. The photobioreactor must be able to maintain a sufficiently turbulent flow in order to insure

the microalgae receive the incoming solar energy evenly. A high yielding photo-bioreactor should have a

cell density of 2–4.25 g/L. At an average weight of 4 pg per individual diatom, such as Chaetoceros, the

density range is between 5 and 10.625x106 cells per ml. At this density the effective solar penetration

start to become limited and it is wise to keep the effective distance of penetration to within 30 cm. To

effectively utilize the incoming solar energy, it is desirable to have the microalgae cells well mixed in the

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growth media. To give each cell an equal opportunity to benefit from the incoming solar energy a degree

of turbulence needs to be maintained in the growth media. However, no study has been done to quantify

the effect of turbulence on the grow rate of microalgae.

Following is a chart showing the yield of diatom in Shenzhen, China during the months of February to

April, 2011. The data show an average daily yield of 0.44 tons of dry diatom per hectare per day. Using

300 useful days per year, the average annual yield is 132 tons per hectare of production surface area. It

should be noted that February and March are normally not best months for the production of diatoms.

HARVESTING MICROALGAE

The separation of microalgae from their growth media can be energy intensive. Traditional methods, such

as centrifuging, filtering, or flocculation, are either energy intensive or difficult to operate, or require the

introduction of chemicals into the process. These chemicals must then be removed before refining can

proceed. Naturally occurring surfactants, which are produced by the microalgae themselves (such as in

the case of Chaetoceros), could provide a partial solution. Such surfactants would allow the use of foam

fractionation to concentrate microalgae. Foam fractionation can be applied to remove 90% of the

Chaetoceros from its culture media, which could then be reused. Hai Yuan [24] working under Wang first

demonstrated the applicability of fractionation to microalgae harvesting. This concept was further

developed by Csordas and Wang. [25]

If a process known as Hydro-Thermal Liquefaction (HTL) is used to obtain crude from the diatom then

the requirement for water-diatom separation can be minimized, and foam fractionation may be used to

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坐标

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Diatom Yield: Shenzhen, February - April, 2011

干重(g/l)

每日每公顷产量(吨)

平均干重(g/l)

平均每日每公顷产量(吨)

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harvest diatom because Hydro-Thermal process requires certain amount of water and the process itself is

quite tolerant of water presence.

OPTIMIZATION OF PHOTO-BIOREACTOR EFFICIENCY

It is important to note that most bio-productions, such as farming, are essentially batch processes. You

plant corn and wait months for it to grow to maturity. At the beginning the corn plant does not take full

advantage of the resources available. The longer the time required for plant growth the less efficient is the

plant’s ability to utilize the total available solar energy. The diatom Chaetoceros has a very short growth

cycle. Under subtropical condition, Wang and his group have demonstrated that by using 20% of the

algae produced during the previous day as seeds, their photo-bioreactor can fully restore the diatom

Chaetoceros density during the following day, which means 20% of Chaetoceros will grow to a full 100%

density during a single day. Nevertheless, this is still a batch process, repeated on a daily basis. Since we

now have the capability of continuously harvesting Chaetoceros, or other diatoms, by continuous foam

fractionation for example, we can maintain the algal density in the photo-bioreactor at an optimal level at

all time, thus greatly increasing the ability of the photobioreactor to continuously convert the solar energy

into cell growth.

BIO-CRUDE FROM THE DIATOM

Getting bio-crude from the diatom, or any microalgae, is a complex process that can involve a number of

issues. For example, if we have a process that tolerates a moderate amount of moisture in the harvested

algae, then we can avoid having to dry the algae. Removing moisture from algae is expensive.

Another issue which needs to be raised here is more fundamental: just how much oil is there in the algae?

On the surface, it is an easy question, we look for lipids and all forms of saturated and unsaturated fatty

acids and extract them and that is how much bio-crude there is. But is it? It is well known that by

manipulating the nutrients in the growth media we can affect the oil content of the algae we produce.

Uunder nitrogen-starved conditions, it has been reported that triacylglycerols can account for 70% of the

total cell volume in Chaetoceros gracilis. There are, however, a wide variety of lipids found in diatoms

including membrane-associated glycolipids and extrachlorplastic phospholipids. The proportion of lipids

can vary greatly even within species and depends on the culture conditions [26] and the cultivation

methods. [27]. What if we wish to produce bio-crude and therefore do not have to worry about preserving

the chemical structure of the lipids? To further complicate the issue, let us assume that future advances in

the HTL process would eventually allow us to take advantage of all the organic carbon without having to

destroy the lipid structure. In that case, what is the oil content of an alga? Why are we even want to be

concerned about the oil content? Clearly, it is the organic carbon content and not the oil content that we

should be concerned of.

We have been mistakenly over concerned over oil content in our search for an alga that would lead us to

competitive bio-oil production? What should be clear to us is the importance of organic carbon

production per hectare per day, which means growth rate and organic carbon content will outweighs oil

content in the selection of algae species. This has important implication for genetic and genetic

engineering work relating to microalgae and bio-oil production.

BREAKING CELL WALL

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An alternative method that seems promising subjects the diatom cells to high pressure followed by a

quick release (HPQR) of pressure. Rossignol et al. [28] stated that a rapid transfer of diatoms from a

region of high pressure (30–270 MPa) to one of low pressure (0.1 MPa) can cause cell breakage. Their

experiments have shown that a significant breakage of Haslea ostrearia cells occurs at 30 MPa. Kelemen

and Sharpe [29] determined and compared the pressure required to disrupt half the population of various

microorganisms. They showed that cells are not broken at one pressure but a certain pressure must first be

applied before disruption starts. The microalga Chlorella was the most fragile species and was damaged at

48 MPa. The HPQR cell disruption method has proven its efficiency for recovering intracellular

metabolites from diatoms. The technique is complementary to, or competitive with, conventional

laboratory-scale techniques such as Sonication[30] or shear-based systems previously applied to

marennine extraction. [31] This technique is clearly suited for the separation of natural compounds from

microalgae or cyanobacteria (nucleic acids, enzymes, proteins, pigments, etc.). A precise particle size

analysis of the resulting debris (by laser technique) can give useful information for the choice of further

metabolite separation and partial purification steps such as ultrafiltration and nanofiltration. [26] For the

separation of fatty acids no filtration is required. Investigations and additional engineering of existing

techniques such as HPQR and the development of other approaches for lipid release will further enhance

the development of microalgae-based biodiesel toward commercial viability in the near future. Since all

the research efforts have been limited to laboratory exploratory experiments, the cost-effectiveness of

such techniques remain unknown.

Apply one or more strong but very short electric field pulses to diatoms suspended in an aqueous medium

with a moderate electrical conductivity, if the field is big enough, a large number of transient aqueous

pores should be created. If the internal space within diatoms has a high concentration of dissolved ions

and molecules an osmotic pressure difference exists, and now water from the external medium should

move in, increasing the pressure within "lipid bilayer membrane-protected" regions of the diatom. The

pressure difference will be large enough to rupture the diatoms. The mean lifetime of such pores is

controversial, maybe one or more seconds, so more than one pulse may be needed. The temperature rise is

generally small. [32, 33, 34, 35]

Richard Nuccitelli of BioElectroMed Corp. [36] stated he had routinely used pulsed electric fields of 30

kV/cm that make nanopores in lipid membranes and also send shock waves through water. However, he

did not see anything released when he tried the technique on diatom we supplied him. The nsPEF-induced

pores were very small (1 nm) and only stay open for a few minutes at most.

It is our experience that both centrifuge and freezing will break the diatom frustules apart and that we can

extract the lipids using solvents. However, no accurate data has been kept on the separation of those

frustules.

HYDRO-THERMAL LIQUEFACTION OF DIATOM INTO CRUDE OIL

The diatom biomass has relatively high water content (80–90%). The high water content and inferior heat content makes the microalgal biomass inefficient to be used for heat and power generation directly, thus necessitating pre-treatments to reduce water content and increase the energy density. [37, 38, 39, 40].

Direct hydrothermal liquefaction in sub-critical water conditions is a technology that can be employed to convert wet biomass material to liquid fuel. This technology is believed to mimic the natural geological processes thought to be involved in the formation of fossil fuel, but in the time scale of minutes or hours. The process essentially utilizes the high activity of water in sub-critical conditions in order to decompose biomass materials down to shorter and smaller molecular materials with a higher energy density or more valuable chemicals. Goudriaan et al. claim the thermal efficiency (defined as the ratio of heating values of bio-crude products and feedstock plus external heat input) for the hydrothermal upgrading process (HTU®) of biomass of a 10 kg dry weight h−1 pilot plant is as high as 75%. The

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main product of the process is bio-crude accounting for 45% wt. of the feedstock on dry ash free basis, with a lower heating value of 30–35 MJ kg−1, which is compatible with fossil diesel and can be upgraded further. [41 As moist biomass can be easily heated by microwave power, a process similar to the HTU® process using a novel microwave high-pressure (MHP) reactor has been developed in order to further minimize the energy consumption of the process [42]. Recent work by Tylish, et al (43) converted the marine microalga Nannochloropsis sp. into a crude bio-oil product and a gaseous product via hydrothermal processing from 200 to 500 C and a batch holding time of 60 min. They estimated the heating value of the bio-oil to be about 39 MJ kg-1, which is comparable to that of a petroleum crude oil. The H/C and O/C ratios for the bio-oil decreased from 1.73 and 0.12, respectively, for the 200 C product to 1.04 and 0.05, respectively, for the 500 C product. Major bio-oil constituents include phenol and its alkylated derivatives, heterocyclic N-containing compounds, long-chain fatty acids, alkanes and alkenes, and derivatives of phytol and cholesterol. CO2 was always the most abundant gas product. H2 was the second most abundant gas. The activation energies for gas formation suggest the presence of gas-forming reactions other than steam reforming. Nearly 80% of the carbon and up to 90% of the chemical energy originally present in the microalga can be recovered as either bio-oil or gas products. Integrated utilization of high temperature and high pressure conditions in the process of hydrothermal liquefaction of wet biomass would significantly improve the overall thermal efficiency of the process. Suitable systems for such utilization are an internal heat exchanger network, or a combined heat and power (CHP) plant. A thermodynamic study, for example, has been performed to calculate the energy efficiency of the HTU process on the basis an integrated heat exchanger network [44]. Many past research in the use of hydrothermal technology for direct liquefaction of biomass can be found in the literature. Only a few of them, however, used algal biomass as feedstock for the technology. Minowa et al. [45] report an oil yield of about 37% (organic basis) by direct hydrothermal liquefaction at around 300°C and 10 MPa from Dunaliella tertiolecta with a moisture content of 78.4 wt%. The oil obtained at a reaction temperature of 340°C and holding time of 60 min had a viscosity of 150–330 mPa and a calorific value of 36 kJ g−1, comparable to those of fuel oil. The liquefaction technique was concluded to be a net energy producer from the energy balance. In a similar study on oil recovery from Botryococcus braunii, a maximum yield of 64% (dry wt. basis) of crude oil was obtained by liquefaction at 300°C catalyzed by sodium carbonate [46]. Aresta et al. [47-49] have compared different conversion techniques viz., supercritical CO2, organic solvent extraction, pyrolysis, and hydrothermal technology for production of microalgal biodiesel. The hydrothermal liquefaction technique was more effective for extraction of microalgal biodiesel than using the supercritical carbon dioxide [57]. Zhou et al reported using hydrothermal liquefaction to convert E. prolifera to bio-fuel at 300 C with a reaction time of 30 minutes and the addition of 5% by weight of Na2CO3 [55]. Anastasakisa and Ross [51] reported on the HTL of brown macro-algaLaminaria Saccharina. From these studies, it is reasonable to believe that the hydrothermal liquefaction is the most effective technological option for the production of bio-diesel from microalgae. Nevertheless, due to the level of limited information in the hydrothermal liquefaction of algae, more research in this area would be needed.

Using freeze-dried diatom produced in Shenzhen, China, by Shenzhen Jawkai Bioengineering R&D Center, Professor Yuanhui Zhang of the University of Illinois at Urbana has shown that very preliminary data indicated crude oil yields at 300C and 320C were 56.1% and 58.1% based on the dry weight of the feedstock,. There was no aqueous product produced during the conversion of diatom, instead water was consumed. A second test however, showed crude oil yield at on 36%. It is suspected that the test result may be more accurate.

Table 1 HTL results of converting diatom, University of Illinois

Bio-Crude Solid residue Gas Toluene solubility[a]

300 56.1% 39.4% 4.5% 60%

320 58.1% 37.4% 4.5% 63% [a]

On the total weight of raw oil basis

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A subsequent test showed a crude oil output of 32%. It is believed the second test was more accurate. Even the lower value gave a clear indication that direct conversion of diatom into bio-crude must be taken seriously. The energy efficiency of the hydrothermal process would depend, to a large extent, upon the efficiency of

heat recovery. Modern heat exchangers normally can have an efficiency exceeds 90 percent. In an

integrated system, heat from an oil refinery or a coal power plant would

Epilogue

The major building blocks for an open diatom production system are all here. A system of outdoor open production of preferred diatom while controlling the wild invasive species and predatory aquatic animals that feed on the diatoms has been in operation in Shenzhen, China since late 2009 with an average annual yield 132 metric tons (dried biomass) per hectare. This means an annual production of 1 million metric tons of crude oil will require only about 500 km

2 of surface area. This will

allow the production of large quantity of biomass within reasonable land size. Hydro thermal processes can then be used to efficiently obtain over 30 percent of crude oil from the biomass produced. The production of diatoms is much more affected by variations in available solar irradiation than variation in temperature. Our review of literature has shown there are low temperature diatoms available. Therefore, they can be produced in desert, where saline water is available, and in the temperate zone, at low temperatures. Diatoms have been found in desert and high altitude lakes. To produce diatom fuel competitive economically will require a complex integrated system. The major costs of algae production, not counting facility investments, are fertilizers including carbon dioxide, and electricity. These items alone would make producing competitively priced diatom fuel near impossible. Thereby they must be reduced or eliminated; better yet, whereas possible, producers of diatoms should seek to be compensated for the consumption of pollutants, such as industrial heavy metal waste water, city waste water and carbon dioxide. The frustules of diatoms are excellent material for the removal of heavy metal from industrial waster water. One of the worst pollutions the world faces today is caused by city waste water and it is, incidentally also, a very good fertilizer. Modern societies are used to paying for waste water management. If we are to use treated waste water to replace fertilizers, we can save the cost of fertilizer, and by cleaning up the waste water, we should also gain payment for service rendered. The world is full of lakes and rivers polluted by waste water discharge. A famous example, the world renowned Kunming Lake (Dianchi) is so polluted that in Summer time the smell becomes insufferable. The reason for the pollution is simple: the amount of nutrients that goes into the lake annually exceeds what the lake itself can remediate. Billions of RMB have been devoted to solve the problem to no avail. The solution seems to be simple: reduced the nutrient load of the incoming water sufficiently, and in time the lake will right itself. The solution is to treat the city waste water at the point where they leave the treatment plant by using it to grow diatom, thus remove the nutrient from the waste water. The modern waste treatment plant removes little nutrient from the city waste water. It mostly just converts the organic nutrients into inorganic ones. We have demonstrated in our Shenzhen facility that we can sufficiently consume the nutrients in the waste water by using it to grow diatom. From the beginning of the NREL project, funds and efforts were directed in finding a best species for the production of bio-fuel. Millions of dollars were spent on the effort, and thousands of species were examined both in the laboratory and tested in the field. It is an effort doomed to failure. To produce algae year round and compete with varying wild species, it is obviously necessary for us to cultivate different species during different time of the year. Even in Shenzhen, which enjoys a subtropical climate, it is necessary for us to cultivate several species of diatom during the year. To meet this requirement, we have specially developed a procedure that allows us to continuously produce the current most competitive diatom from the surrounding ocean bay to replace part of our diatom, thus maintaining its competitive vigor. It is well known that diatoms get smaller as they subdivide and new seeds are needed to maintain

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the vigor of the growth. Partial but continuous replacement of the species under cultivation with diatoms from the wild will insure that. By using locally developed seed we also avoid the pollution that can come from the introduction of foreign species into local waters. To reduce the cost of electricity, we need to consider wind power. Wind is another underutilized source of renewable energy because there are problems in converting wind energy into useful electricity. Drastic variation in wind can occur suddenly. For this reason the power grid operators must limit the percentage of wind generated electric power accepted by the grid. The grid operators are forced to limit the amount of wind generated power they can accept by their inability to modulate the disturbances caused by the sudden changes in wind power. An open microalgae bioreactor system can be designed to tolerate extreme variations in its power supply. A wind power generating system requires large space since units of the system cannot be located in close proximate. An open microalgae bioreactor system can make full use of the vacant spaces. The ability to complement each other in energy use, in space allocation, and to share cost in land preparation, can improve the economical efficiency of the joint operation to insure the profitability for both.

The economic viability of a diatom for fuel facility requires that as many co-products are utilized as possible, as is the case with current petrochemical processing facilities. Many potential bioproducts are possible, including specific organics like food-grade betacarotene, pharmaceuticals, pigments, as well as compounds like polysaccharides, carbohydrates, and surfactants.

Lipids from microalgae can be used to produce cooking oil. The high quality lipids will produce excellent oils for human consumption. The shortage of cooking oil is a serious problem for the world. As the world population increases, especially in the rapidly emerging economies, the demand for cooking will increase faster than the demand for fuel oil; for after all there are other energy sources while there is no substitute for cooking oils.

Notes and Comments

Paul Voosen, an E&E reporter, in an article published on March 29, 2011, said that ―…During World

War II, German scientists first attempted to produce oil from the microbes, discovering that green algae,

when deprived of nutrients, devoted more than two-thirds of their weight to oils. The oil built up slowly,

though, and the algae, investing their energy in survival, grew at a tepid rate -- a problem to this day.

After the war, mass cultivation of algae began in a few modest, translucent bags on an MIT rooftop,

focusing on protein-rich food production. The 1950s soon saw a bubble similar to the past few years, with

companies saying they could rapidly expand algae production in three years with drastic drops in price,

said Rene Wijffels, an engineer at Wageningen University in the Netherlands. Those claims amounted to

little, he added.

Given this precedent, it was natural that the Department of Energy's Aquatic Species Program, which was

launched in response to the 1970s oil crisis and ran from 1978 to 1996, focused on fat-producing algae.

Scientists collected some 3,000 strains, several of which seemed ripe for biodiesel. Ponds were built in

Roswell, N.M., to demonstrate that the algae could be, in effect, farmed. (The researchers soon discovered,

to their chagrin, that wild algae had overtaken the ponds.) The program ended in the face of persistent low

oil prices, but in an influential final report, its leaders prophesied algae's eventual return….‖

This preoccupation with oil content has been the curse of the development of algae-to-biofuel effort. Two

things are worthy of note here: (1) Algae grow fast but produce oil slowly, (2) algal farming failed

primarily because wild algae had a tendency to overtake the algae to be cultivated. To be successful,

microalgae’s model should be agriculture. Like in farming, the first thing needs to be done is to improve

Producing Algal Biofuel for Profit Page 9

the productivity of algae, and they need to protect it from predators. The algae need to produce

appropriate products, and an efficient way is needed to harvest algae oil.

The most aggravating myth about algae stems from a simple chart comparing the oil yields of common

crops. One version was published by Yusuf Chisti, a biochemist in New Zealand, in 2007. It portrays

algae, conservatively, as 130 times more productive than soybeans. Over the past five years, no other

algae fuel paper has been as widely cited.

There was a fundamental mistake people outside the algae business made when looking at the chart. They

extrapolated speedy growth rates from open waters and ideal conditions to the industrial setting necessary

for commercial cultivation, said Greg Stephanopoulos, a biochemical engineer at MIT and a longtime

expert in bacterial manipulation.

A frank assessment of algae fuel ponds released last fall by researchers at Lawrence Berkeley National

Laboratory found that the only economically viable route for algae ponds would be for use in wastewater

treatment, creating oil on the side. Without such a dual use -- and several regions do use algae for this

purpose -- oil costs from the pond would run between $240 to $330 a barrel, more than double current

crude prices. And the same reason will forced us to make use of waste carbon dioxide, and wasted wind

power.

Our paper has indicated that the technical problem s– such as controlling the wild algae and predator

aquatic animals have been solved. We have suggested a way that producing bio-fuel and bio-oil can be

made profitable - by integrating diatom production with waste water treatment, using CO2 from chemical

plants, and by taking advantage of the wind power and making use of other co-products. It is now time to

take a second at the age old problem and try once again with real hope.

It is all about Carbon, Stupid!

If we are to produce bio-fuel. It is most likely we will end up using Hydro-Thermal Liquefaction to obtain

crude oil from the diatom. Note that I said ―obtain‖ and not ―extract‖. Because Hydro-thermal process is

all about converting carbon to oil and not about extracting existing oil from the algae. Note again that

algae grow fast but produce oil slowly; it should then be easy for us to see that when we grow algae we

are actually interested in growing carbon and not oil. Genetic engineers please note!

The whole process is about converting inorganic carbon into organic carbon. Whether the organic carbon

is in the form of oil or sugar or anything else, matters little.

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