Biofuels Midterm 2
375 million acres of rice world wide - 3 million in US
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Who are the Major Microalgae Players?
Diatoms, Cyanobacteria, Algae Microaglae are minature biochemical factories that are photosynthetically efficient CO2 fixers that can grow in a variety of water environments.
Fuel Efficiency of Biodiesel Compared to Petrodiesel
Diesel engine relies on the heat of compressed air to trigger ignition rather than a spark.This leads to a 15% increase in the efficiency over gasoline engines for converting the chemical energy of fuel into mechanical energy.
Light Determines Algae Biofuels Production
Diurnal cycles Seasonal Light Variations Wavelength Utilization as well as temp. fluctuations and evaporation
Pathogens and predators of algae
chytrid fungi and rotifers
Processing Green Crude to Fuel
grow, harvest, extract, concentrate.The concentrated algae oil can go directly to a traditional oil refinery
2nd Generation Biofuels Aquatic Biomass: Cyanobacteria, Diatoms and Algae
- In many cases, aquatic systems can produce biomass at a faster rate than any land system. - Aquatic systems do not tend to compete for resources with current agricultural systems.
What components of a plant are important for cellulosic biofuels production?
Cellulose(long chain of glucose molecules) Hemicellulose(2nds most abundant constituent) lignin( conidered the cellular glue functioning in strength, stiffness and resistance to invasion)
2nd Generation Biofuels
Cellulosic Ethanol from herbacious and woody crops.
The Cost of Ethanol Production
Cellulosic Ethanol is still Cost Prohibitive.Food, Conservation and Energy Act of 2008 - $1 billion in incentives for cellulosic feedstocks and biofuel production including $1.01 per gallon tax credit for cellulosic biofuel production and cost share payments
Lifecycle Analysis of Biodiesel Feedstocks
Fossil Enery Ration: 4.56
Cellulosic Feedstocks- Herbaceous Grasses
bagasse,corn stover, swithcgrass, miscanthus
Preparing Lignocellulose Biomass
harvest( source and topography), size reduction(straw less energy). pretreatment(steam or dilute acid), Biochemical hydrolysis( Cellulases, this is expensive part 25kg/ton of cellulose), fermentation of sugars to ethanol
Anaerobic Conversion Process
hydrolysis, acidogenesis, acetogenesis( creates acetic acid), methanogenesis.
Biochemical Conversion of Cellulose to Ethanol
1. A "pretreatment" phase, to make the lignocellulosic material such as wood or straw amenable to hydrolysis 2. Cellulose hydrolysis (cellulolysis), to break down the polymer molecules into simple sugars 3. Separation of the sugar solution from the residual materials, notably lignin 4. Microbial fermentation of the sugar solution 5. Distillation to produce roughly 95% pure alcohol 6. Dehydration by molecular sieves to bring the ethanol concentration to over 99.5%
Barriers to Hydrogen Production
Basic science, fermentative, engineering
Biological Hydrogen Production Pathways
Can produce H2 directly from water and sunlight.Can produce H2 from water and fixes nitrogen. Can produce H2 without light and uses a variety of carbon sources. Uses a wide spectrum of light energy and different waste materials.Goal 12 mol H2 per mol hexose
Methods of Harvesting
Centrifugal Sedimentation-Rapid but energy intensive process Biomass Filtration-Most appropriate for relatively large microalgae and is not efficient for algae approaching bacterial dimensions
Lignin Degradation in Wood Feeding Insects
Chemical changes in lignin upon passage of un-degraded wood through wood-feeding insect gut systems results in evidence that microorganisms in these systems are capable of degrading lignin.
Biogas -Waste to Energy
Conversion of organic matter directly to a gas, usually a mixture of mainly methane and carbon dioxide with small quantities of other gases such as hydrogen sulfide. Cows are responsible for about 18% of greenhouse gas emissions
Lifecycle Analysis of Lignocellulosic Biomass
Corn and Corn Stover can act to reduce GHG emissions, but Miscanthus and Switchgrass can actually serve as net carbon sinks! 7.54 from gas 13.17 from switchgrass
What are "omics" technolgoies
Genomics - DNA Study of the genomes of organisms Transcriptomics - RNA Expression profiling of all RNA within a cell or organism Proteomics - Proteins Study of the structure and function of proteins Metabolomics - small molecules Collection of metabolites in an organism
Synthetic Biology
The design and construction of new biological parts, devices, and systems, and the re-design of existing, natural biological systems for a dedicated purpose
How is Vegetable Oil Made
Threshing( loosening the deible parts of a crop) Drying (Natural and artificial, lower moisture for storage or further processing) Cleaning Extraction
Chemistry of Biodiesel
Tranesterification of Triglycerides. FFAs (reacted with base, for soap)
Cayan Video (climate change: water and energy in california)
arid region. 19% of electricity is in some way tied to water.biggest water use in SD is landscape/outdoor water use. highly variable rain. warming intensified in summer. length of heat wave spell will continue to increase per day. less snow more rain driven by warmer temps.
Herz (thermochemical conversion)
best way to use waste biomass: agricultural waste, forest clearings, MSW. Cellulosic biomass is stong, heat: liquids, gases, solids are primary products(endothermic)-require energy input supplied by secondary products which are exothermic.dual fluidized bed gasifier steam and acid GTL- product gas from biomass gasifier can be used to make liquid fuels. syngas is H2 and CO. all catalyzed by porous solid catalysts. water gas shift reaction to adjust H2/CO .
Synthetic biology is still in need of rapid gene sequencing, accurate gene synthesis, sensitive metabolite detection methods, high throughput screening of synthetic microbes, and multifunctional microenvironments for individual cells.
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The European Union alone produces 1,284 x 108 tons of cow manure every year
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Rapeseed (Canola) Biodiesel
10-15% of the World Oil Crop. Production away from equator where there is dry weather and shorter growing seasons. Production away from equator where there is dry weather and shorter growing seasons. U.S. only produces 0.7 million metric tons of canola, but we import a significant amount from Canada. Canola primary oilseed in EU
Global Oil Seed Crop Production
90% of Oil Seed Production from the U.S. is from Soybeans. 2011/12, 441 million metric tons of oil seed crops were produced
Hydrogen Production and Use
95% of Global Hydrogen Production is from Fossil Fuel Sources - primarily via the thermocatalytic reformation of natural gas
Genetically Modified Organism -GMO
A genetically modified organism (GMO) or genetically engineered organism (GEO) is an organism whose genetic material has been altered using genetic engineering techniques. Use recombinant DNA technology and DNA molecules from a different species to introduce a new gene into an organism Need all aspects of this to be a GMO DNA must be from another species Must use recombinant DNA technology - lots of organisms exchange DNA! Can often achieve the same result with genetics - but takes time
Important Operational Parameters
A variety of factors affect the rate of digestion and biogas production; Elevated Temperature Mesophilic 30 - 38 C Thermophilic 49 - 57 C pH is important - should be between 5.5 and 8.5 Carbon to Nitrogen Ratio of 20-30:1 Organic Loading Rate - or residence time
Toxic Byproducts can Limit Fermentation
Acid pretreatment releases low molecular weight fatty acids, aromatic compounds and dehydrated sugars toxic to yeast.Secondary metabolite production can be toxic to microorganisms
Biosynthesis of Fatty Acids
Activation of a malonyl, acetyl or acyl group by a thioester linkage to the fatty acid. Hydrocarbon chain is extended by condensing two carbons from the malonyl-CoA and the activated acyl group releasing carbon dioxide. Reduction of the beta-keto group yields and alcohol which is subsequently dehdyrated creating a double bond. Reduction of the double bond yields a saturated fatty acyl group
Producing Biogas is Possible
Aerobic Digestion-Commercial composting & Activated sludge wastewater Higher Reaction Rate Typically do not produce useful fuel gases (CO2 and H2O) Anaerobic Digestion-Wastewater treatment & decomposition of food wastes and landfill biomass Bacterial Fermentation Process Typically produces fuel gas called biogas (CH4 and CO2)
Crop Protection
After energy and fertilizer pesticides are large expense in agriculture 2% of your genome is brain function. 25% is dedicated to fighting infection.Looks much like Industrial Agriculture. Naturally Resistant Strains are first line of defense. Cropping Practices - crop rotation and consortia. Resistance genes moved into production strains Breeding and Selection Genetic Engineering Chemical Protectants - herbicides and pesticides These are expensive so used sparingly
Cetane number
As cetane increases the ignition delay decreases the main combustion phase increases, should not be higher than 65.
Important Conversion Technologies
Biochemical(polysaccharides broken down into free sugar molecules and the sugar molecules are used in fermentation) Thermochemical( feedstock is gasified to produce syngas and the syngas is used to reformat hydrocarbons or in fermentation)
Cost of Biodiesel Production
Cost of feedstock is a significant limitation (90%) for the development of biodiesel fuels - Main limitation is that these are cooking oil!
Diatoms
Diatoms are unicellular microalgae distinguished by silica cell walls. grow under bloom conditions.
Analysis of Raw Landfill Gas
Exploitation of landfill gas is economically most feasible after 1 year.
Extraction & Purification of Algae Biomass
Extraction: concentrated algae is processed using proprietary technology to extract oil and nutrients
Examples of Bioenergy Genomes
Feedstocks & Feedstock Models,Fuel Producers,Biomass Degraders
Important Traits of Cyanobacteria
Fix Nitrogen from Air Some are Extremophiles Regulate Flotation Grow as Mats Make Secondary Products Some are Naturally Transformable
Closed Photobioreactor Systems
Flat plate, tubular, column(BEST). For any engineered system The capital expense (CapEx) must be matched to the product revenue.
negative environmental consequences of N fertilizers
GHG emissions during production, nitrate runoff (hypoxia), nitrous oxide emissions from soils in response to the presence and cycling of inorganic N
Nitrogen is important for production of corn for both food and ethanol production
Grain saw a 73% increase in yield a t the highest nitrogen concentration
Two Important Parts of a Plant's Lifecycle
Growth: cellulose-polysachh beta glucose, most organic compound on Earth, 33% of all plant matter for structure. Starch- poly alpha for energy storage Reproduction: Seed dispersal and Seed germination
History of Photolysis Hydrogen Production
H2-photoproduction observed in cyanobacteria in the late 1890s. Jackson and Ellms, "On odors and tastes of surface waters". Mass. Board of Health 1896. Gaffron and Rubin reported eukaryotic algal H2 photoproduction in the late 1930s. [FeFe]-hydrogenase. Cyanobacteria and algae catalyze H2-production in the light from nitrogenase and/or [NiFe]-hydrogenase. Hydrogenase systems theoretically more efficient than nitrogenase systems. Nitrogenase requires 2 ATP/e- ATP and not electrons become limiting
Biomass Productivity for Open Pond Systems
Harvesting is the most expensive part of the process higher biomass concentration reduces the effective harvesting cost
Agricultural Expenses of Cellulosic Crops
Harvesting, Baling, and Storing Cellulosic Feedstocks are the most important items to consider in the cost of producing cellulosic feedstocks
Indirect Photolysis
Heterocyst formation allows for the fixation of nitrogen in the presence of oxygen.H2 and O2 production are separated both temporally and spatially
Environmental Aspects of Cellulosic Feedstocks
High water efficiency (c4 plants 6%) and carbon sequestration(switchgrass can sequester 1-10 tons/hectare)
Cellulosic Feedstocks- Woody Species
Hybrid oplar, willow, eucalyptus
Environmental Impact of Biogas
In 2000, an estimated 282.6 million tonnes of anthropogenic methane was released. Biogas is particularly important because of its dual GHG benefit Reduction of emissions of methane Reduction of the release of CO2 from fossil fuels
Identifying Microorganisms Without Culturing
In Situ hybridization probed for bacteria (green) and several phylogenetic groups of methanogens (red) found within mesophilic sludge granules.
What about unculturable organisms?
It is estimate that less than 2% of bacteria can be cultured in the laboratory. How do we access the other 98% of microbial resources? DNA Technologies.
Cellulosic Biomass Composition
Lignin associates with cellulose and hemicellulose negatively impacts the release of polysaccharides during the pretreatment process
Dark Fermentation Hydrogen Production
Majority of microbial hydrogen production comes from the anaerobic metabolism of pyruvate during catabolism of various substrates
Five Challenges for Synthetic Biology
Many parts are still undefined Circuitry is unpredictable, or not robust Complexity of pathways and side reactions Unintended effects on host cell Variability can lead to unreliability
Is Miniaturization the Future of Synthetic Biology?
Microfluidics - technology that deals with fluids at a micro scale.Enables a large number of individual experiments Allows for the investigation of individual cells in a short time using a wide range of environmental parameters with less labor
Oil Production in Algae
Needs 5,000 gal/acre X 30 million acres = 150 billion gal
Outdoor Ponds
Open pond systems are less efficient, but also less expensive than closed photobioreactors for a number of reasons
Cellulosic Biofuels "Opportunities & Challenges"
Opportunities: Non-edible part of plants (negate food vs. fuel debate) Most abundant organic material on Earth (lots of it) Largely sugar polymers (glucose) that can be converted to ethanol or other fuels by chemical (reforming) or microbial (fermentation) processes Challenges: Cellulose sugars trapped in insoluble fibers Fibers held together by hemicellulose ("difficult" sugars) & lignin (phenolic polymer) Not all plant cells walls are the same (different cellulose, hemicellulose, lignin contents, etc.) There is a reason we make houses out of wood!
Biogas Production from Landfills
Per capita generation of municipal solid waste in the U.S. is 1.19 tonnes/year. Only about 7% of the 336 million tonnes of MSW generated in the U.S. is used for energy
Photo-Fermentation
Photosynthetic bacteria including Rhodopseudomonas and other purple non-sulfur bacteria have the capacity to produce hydrogen Nitrogenase Dependent Hydrogen Production Nitrogen fixation and H2 production activity; stimulated by light and strongly inhibted by oxygen,ammonium and nitrogen as
Cold flow
Plug fuel lines and filters, decreases with % of carbon atoms and increases with double bonds
What will bioprospecting of this do for bioenergy? - Traits
Rapid growth High density High oil or energy content Resistance to predators and pathogens Easy in harvesting Efficient nutrient utilization Seems unlike all of these traits will be in a single organism
What are the Challenges that Remain for microalgae
Reaching world scale production (engineering) Need to reach economies of scale Economic viability with products Food and feed probably economically viable first Economic viability of fuel products Carbon tax may be essential Economic sustainability - viability without subsidies
Harvesting Technology
Recovery of microalgae biomass usually requires at least one solid-liquid separation step which is both a challenge and adds to the cost of production bulk harvesting-seperation of biomass from bulk water thickening- concentrate the biomass
Methane is a strong GHG and its levels are increasing faster than CO2
Releasing methane into the atmosphere increases global warming and wastes useful energy!
Reasons for Unculturability
Required Nutrient Not Present Culture Media is Toxic Another Bacteria Inhibits Growth Bacterium Needs Another Bacterium
Bioprospecting
Scientific research that looks for a useful application, process, or product from nature, often these are found from organisms inhabiting specific niches such as extreme environments.
Soybean Biodiesel
Soybeans represent 90% of the U.S. total oil seed production. In 2011, we produced 3.06 billion bushels of soybeans, second largest crop in the U.S. Oil Content of seed 20-22%. 59-92 gallons per acre biodiesel. 73% of US Biodiesel is produced from soybeans Largest export is to China 895 million bushels
Metagenomics
Study of genetic material recovered from an environmental sample Always multiple species and often extremely complex Can be used to identify species present, or identify new genes
The Role of Synthetic Biology in Biofuels
Synthetic biology - ability to design and chemically synthesize genetic sequences that can be imported into host cells.Cells can now be produced from computer-designed genome sequences
Unsaturated bonds in fatty acids are good in your diet Not so good in biodiesel - makes the product unstable
Tallow,lard,grease
Process of Bioprospecting
Temp, Desiccation, salinity, pH
Importance of Mixing
Temperature Stratification, Light Penetration, Mixing results in increased light utilization and increased gas exchange (O2 out and CO2 in) resulting in increased biomass productivity - but mixing is an expense
What's in a Seed?
Triglycerides, FFAs, Phytiseterols Triglycerides are 90-98% total lipid mass in seeds
Why Convert Cellulose to Fuel?
US agriculture produces ~1 billion tons/yr cellulosic "waste" At 50 gal/ton that equals 50 billion gallons ethanol Total process could produce ~30% of transportation fuel This includes Ag and forestry waste as well as dedicated cellulosic energy crops Produces liquid fuels (ethanol, biodiesel, etc.) Could be used to make chemical feedstocks (precursors) Energy sources (H2, electricity) - Renewable Power
The Role of Regulatory Organizations in Biofuels
USDA-Concerned with protecting agriculture and the environment from potential pests Regulates all genetically engineered plants prior to environmental stresses FDA-Responsible for ensuring the safety and security of human food and the supply of animal feed Monitor genetically modified foods for the presence of new or altered allergens and toxins EPA-Regulatory authority over substances with pesticidal characteristics including those with risks for human health Regulates pesticides including those pesticide properties associated with genetically modified plants Regulates transgenic algae under TSCA- Toxic Substances Control Act
Productivity for algae
algae have a 3-9% solar energy conversion efficiency. Better solar range and light capture efficiency.
challenges for cyanobacteria
excess carbon stored as glycogen, polar membrane lipids, mini triacylglycerides
Golden Videos on cyanobacteria
extract naturally occuring molecules- sugars, lipids hydrocarbons needed skills and technology- genetic and mol bio for strains, grow in large scale. two pronged approach to move forward- use model organisms and find good production strains. synnecoccus elongotus 2.7mb and homologous recombination
Mayfield Video (Biofuel land and water)
glaciers and icecaps are most of the freshwater on earth, ice and snow is the most of surface water. two biggest are thermoelectric cooling and irrigation dominates freshwater consumption. water required to produce specific foods, 1 hamburger= 2400 liters of water. 40% of corn crop is used to make ethanol fuel. most corn in calfornia from surface water. 3.6gall/per gall of ethanol. 5 trillion gallons of water for fracking. ground water pumping reduces ground level. To improve- contour, biotechnology, precision agriculture.
Mcbride Video (production process for algae)
in agriculture only 4 traits matter: productivity:Methods for algae (open and photobioreactors) tubular photobio is the cheapest of reactors, flat plate has high biomass and light penetration, column is compact. crop protection: chytrid is a problem, uses algae to produce progeny. pumps help kill rotifers. also a biological approach harvest ability:centrifuge, filter, flocculation, dissolved air flotation. converting algae to energy using thermochemical or biochemical. getting it to scale has low GHG and high EROI , product profile.
Schmidt Videos
jatropha- from Central america. generation time is rapid(4-9mo) can reprouce by stem cutting or insect pollination. low cloudpoint (molecules fall out of solution) and high oxidation stability. can grow on subpar prime agriculture land, drought tolerant and is not a food crop. good for biomass,protein and vegetable oils (nonfood). Germplasm foundation for improvement and productivity. inflorescence breeding increased yields
Pour point
lowest temp. at which the fuel will still flow and can be pumped
Hein (renewable nautral gas)
methane is 20x more potent than CO2. methanogenic archaea specifically perform methanation at very high efficiency under a variety of environmental and industrial conditions. produce methane in anareobic conditions common in wetlands and guts of mammals. they haev high mass conversion effieciency biogas- CO2 and CH4,50% is non combustible. Biogas can be upgraded to >98% methane by in situ methanation. more than 270 biogas plants in Europe already inject biomethane into the grid. problem #1: surplus electricity production problem #2: gas challenge solution: power to gas energy storage. renewable natural gas by biocatylytic methanation. carbon free energy with CO2 sources goes to biological methanation goes to the grid
Hildebrand videos (carbon flux)
microalgae are extremely diverse when considering cultivation in different environments, metabolic flexibility, metabolic engineering key issue for biomolecules is carbon flux: inhibit carbon flux maximize the flow of carbon thru lipid pathway. requirements is that need to identify metabolic steps and appropiate tools to manipulate flux. used microarrays for a heatmap. a variety of manipulation leads to increased TAG by redirecting carobn influx knocking out enzyme for carbs, overexpression of a TAG synthess enzyme and by knockdown of a tag lipase all results increase tag with no detrimental effect on growth.
Palenik Video (Nutrient utilization and recycling)
nitrogen application increases plant yields. different crops need different amount of fertilizers. less N2 to soybean.fertilizer production produces GHG and requires energy. Haber-bosch- take N2 out of air to make liquid NH4 and apply to fields to increase crop production. Eutrophication is also a problem with fertilizer production. Nitrate to nitrite. GOAL: Biomass will supply 5% of nations power or 20% of transportation fuel and 25% of chemicals by 2030. nutrient fertilizer will need to be 5x more to achieve this goal. Solutions: nitrogen fixing bacteria and cyanobacteria,develop algal biofuels using recycling principles by hydrothermal liquefaction, nutrient recycling in agricultural systems, waste water recycling. omega and algae wheel
Mayfield Video (Green Algae)
photosynthesis takes place in the chloroplast, the proteins are encoded in the plastid and nucleus. Bovine SAA3 when a mammal eats this stimulates mucus production in gut. nuclear gene expression are poorly expressed or silenced. Gene stacking (red erwith green mito or blue) shows transformation from plant can be used for algae so leads to crop protection. domestication of algae will happen.
Microbial Inoculants may Enhance Fertilizer Efficiency
root nodules and enhanced growth. Many bacteria can function as biofertilizers capable of converting inorganic sources of nitrogen and phosphorus into organic (useable) sources.
Why Algae as a Biofuels Platform
scalability, productivity, sustainability, fungible fuels
mc bride video (bioprospecting)
to find the best strain, genotoype plus environment. xylanase activity in C.reinhartii
Burkart Video (FA metabolism)
type 1 (multidomain) or type 2 (plants andbacteria) FA synthase, acyl carrier proteins. all FA metabolism is in chloroplast. wanted to make medium chain FA by thioesterase engineering and made biodiesel. overexpression of Thioesterase led to increase short-chain FAs. modular synthases (FAS) utilize protein-protein interactions that are critical to catalytic domain interaction with ACP. TEs from vascular plant are not compatible with C.reinhardlgtrg ACP because non cognate protein-protein interactions. .crosslinking probes can be used to understand ACP TE protein-protein interactions.
Biogas Yield Depends on Substrate
used grease and wheat corn highest biogas yield. Most Agricultural Raw Materials produce 52-56% Methane. paper and food waster are suitable substrates.
