TRANSFORMING ALGAE INTO BIO-PLASTIC
S.K ANSARI & SEEMA ANSARI
Updated July 31, 2010
Not this year but maybe next, that plastic wrap in your kitchen drawer could be made of sustainable bio-plastic from algae instead of petroleum. Most of the plastic manufacturing companies have already made a name for itself with compostable bio-plastics made from food starches including corn, tapioca, wheat, and potatoes.
The company sees non-food crops as the next frontier. The bio-fuel industry has been hungrily eyeing algae oil for a number of years because its potential yield per acre could range up to 15,000 gallons, compared to only 50 gallons for soybeans and 130 for rapeseed. The hitch, until now, is developing a cost effective method for growing algae and harvesting the oil. It has been expecting that algae bio-plastic will replace 50 per cent or more of the petroleum content in conventional plastics, with a particular emphasis on single-use applications in the food industry.
Bio-plastics are derived from organic sources like corn, pea starch, vegetable oil and microbes, as opposed to petroleum-based plastics. Some bio-plastics are disposable and some are not depending upon their degradability. Bio-plastics are used for disposable items such as packaging and utensils, and other non-disposable items such as cell phone casings and carpet fibers.
Companies currently use corn starch, tapioca, wheat, and potatoes to make sustainable plastics and will expand its family of products with algae-based resins that could serve as a substitute for the petroleum used in traditional plastics. Algae-based resins represent an outstanding opportunity for companies across the plastic supply chain to become more environmentally sustainable and reduce the industry's reliance on oil. This technology is still in the development phase, but it is believed that breakthrough in this technology could result in a significant new line of business in the years to come.
The researchers foresee algae becoming a leading green resource for bio-fuels and bio-plastics. Researchers have taken step with several companies planning to use algae to minimise the carbon dioxide and nitrogen oxide gases from polluting smoke stacks. The company is also in negotiations with chemical conversion companies interested in converting algae biomass into biopolymers.
Companies have been seeking revolutionary technologies by teaming up with several companies that plan to use algae to minimise the CO2 and NOX gases from polluting smoke-stack environments. Algae from a typical photo-bioreactor are harvested daily and may be treated as biomass, which can be used as bio-fuel or as a raw material source for biopolymer feed stock.
Bio-plastics makers are planning to launch a line of bio-plastic resins based on all-natural algae by the end of 2010. Algae-based resins represent an outstanding opportunity for companies across the plastic supply chain. It is believed that algae has the potential to become one of the most important green feedstock for bio-fuels as well as bio-plastics.
One of the companies in United States Cereplast Inc. has chosen the site for a new facility that will add 500 million pounds per year to its bio-plastic resin production capacity. Research at the University of California, Riverside, and Gwangju Institute of Science and Technology in Korea has identified bacteria that produce semi-conducting nano-tubes. Shell and HR Bio-Petroleum are building a pilot facility to grow algae for bio-fuel oil in Hawaii. Canada's Vertigro has completed the first field test of its algae process in Texas. US DOD is funding research on converting waste materials generated at military bases into motor and jet fuels. Masada and Zapata Associates will produce ethanol and electricity from municipal solid wastes in the Dominican Republic.
Plastic in all its many forms is a reality of modern life. Unfortunately, plastic production has needed petroleum, which evokes images of polluting refineries and a dwindling supply of fossil fuels to feed those refineries. It is highly likely that image is going to drastically change a far greener image as algae becomes the preferred feedstock for a new generation of bio-based plastic products.
Algae is already proving to be a contender in the bio-fuel refinery because of the potential yield of algae oil per acre ñ up to 15,000 gallons versus a relatively meager yield of 50 to 130 gallons per acre for crops such as soybeans and rapeseed. Even the US military is intrigued, as it is trying to actively move towards bio-fuels and bio-plastic food packaging.
The need for alternatives to traditional petroleum-based plastics couldn't be clearer. In the past decade, oil prices have more than doubled, and land fills are rapidly running out of space to dispose of used bottles. In an effort to remain competitive, many companies have begun to develop what are called bio-plastic which are made from either microbial products or plant material.
One of the big leaders in this effort is the German corporation BASF, which has manufactured plastic bottles for the European market for decades. It expects that the global bio-plastics market will be worth about one billion dollar within the next two years, as fuel and disposal costs rise.
American corporations such as Archer Daniels Midland, Dow Chemical and DuPont are also interested in bio-plastic making. However, current market demand favoring traditional plastic bottles means that their research is going forward slowly to make sure the bottles are ready when consumer demands change.
It is hoped that through education and pricing these companies can slowly phase out plastic bottles in favor of bio-plastics once the latter becomes more affordable. In the meantime, there is an emphasis on recycling plastic bottle into new items, such as turning old milk jugs into railroad ties.
TYPES OF ALGAL PLASTICS
* Hybrid Plastics
* Cellulose based Plastics
* Poly-Lactic Acid
Bio-plastics or organic plastics are form of plastics derived from renewable biomass sources such as vegetable oil, corn starch, pea starch unlike fossil-fuel plastics derived from petroleum. Bio-plastics provide the twin advantages of conservation of fossil resources and reduction in CO2 emissions, which make them an important innovation of sustainable development.
Algae serve as an excellent feedstock for plastic production owing to its many advantages such as high yield and the ability to grow in a range of environments. Algae bio-plastics are mainly evolved as a byproduct of algae bio-fuel production. Companies were exploring alternative sources of revenues along with those from bio-fuels. In addition, the use of algae opens up the possibility of utilising carbon, neutralising greenhouse gas emissions from factories or power plants.
Algae based plastics have been a recent trend in the era of bio-plastics compared to traditional methods of utilising feedstock of corn and potatoes as plastics. While algae-based plastics are in their infancy, once they are into commercialisation they are likely to find applications in a wide range of industries.
Bioplastics are plastics manufactured using biopolymers derived from two routes:
* Biopolymers from living organism - these are typically made from cellulose, soy protein and starch.
* Polymerisable Molecules ñ these are typically made from lactic acid and triglycerides, wherein these molecules come from renewable natural resources, and can be polymerised to be used in the manufacture of biodegradable plastics.
These are the following companies which are working on bio-plastic manufacturing:
* Dow Chemicals
* Soley Biotechnology Institute
Algae bio-plastics can be commercialised in the future if they can negate the technical problems they posses. According to Cereplast, the company will launch its new 'Cereplast Algae Plastics' in the market by the end of 2010. But the plastics they produce contain only 50 per cent algae. Plastics that comprise material derived 100 per cent from algae are still not a reality and require innovative developments.
The use of biotechnology techniques can play a key role in conducting the feasibility and sustainability studies in algae bio-plastics. Fermentation and genetic engineering can take the lead in using novel techniques to make algae bio-plastics commercially viable.
The plastics market is worth more than $400 billion and has grown at an average of 3.5 per cent per year over the last two decades. But the contribution made by the bio-plastics is meager. The key reason for the minor contribution is its high cost. The good news is that significant R&D investments are made into bio-plastics by many companies especially in Europe, and these efforts are likely to result in significant cost reductions. Such cost reductions for bio-plastics in general are expected to make algae-based bioplastics more viable as well.
One of the best things about the process of creating bio-plastics from algae is that it still allows for the co-production of algae bio-fuels. For example, oil can be extracted from algae for use as fuel with the remaining algal biomass being used as a source for biopolymer, or plastic, production. Essentially, bio-plastic production can be considered a co-product of algae bio-fuel, giving the same batch of algae even more value.
It is believed that the bio-plastic market is growing and could top 30 per cent of the total plastic market in just 10 years. However, in order for algae to play a major part in this, algae producers need to develop a commercially viable production model.
ALGAE TO SOLVE JET FUEL PROBLEMS
Jet fuel from algae is just months away from producing with the same cost as its fossil-fuel equivalent. A cheap, low-carbon fuel would not only help the giant fuel consumers to wean themselves off oil addiction, but would also hold the promise of low-carbon driving and flying for all.
One of the projects has already extracted oil from algal ponds at a cost of $2 per gallon. It is now on track to begin large-scale refining of that oil into jet fuel, at a cost of less than $3 a gallon. That could turn a promising technology into a market-ready one. Researchers have cracked the problem of turning pond scum and seaweed into fuel, but finding a cost-effective method of mass production could be a game-changer.
The work is part of a broader effort to reduce the military's thirst for oil, which runs at between 60 and 75 million barrels of oil a year. Much of that is used to keep the US Air Force in flight. Commercial airlines - such as Continental and Virgin Atlantic ñ have also been looking at the viability of an algae-based jet fuel. Further technology development is being carried out to bring oil from algae.
Unlike corn-based ethanol, algal farms do not threaten food supplies. Some strains are being grown on household waste and in brackish water. Algae draw carbon dioxide from the atmosphere when growing; when the derived fuel is burned, the same CO2 is released, making the fuel theoretically zero-carbon, although processing and transporting the fuel requires some energy.
The Obama administration had earlier awarded $80 million in research grants to a new generation of algae and biomass fuels. The US Air Force wants its entire fleet of jet fighters and transport aircraft to test-fly a 50-50 blend of petroleum-based fuel and other sources ñ including algae ñ by next year.
The switch is partly driven by cost, but military commanders in Afghanistan and Iraq are also anxious to create a lighter, more fuel-efficient force that is less dependent on supply convoys, which are vulnerable to attack from insurgents. Give the military the capability of creating jet fuel in the field, and you would eliminate that danger. "In Afghanistan, if you could be able to create jet fuel from indigenous sources and rely on that, you'd not only be able to source energy for the military, but you would also be able to leave an infrastructure that would be more sustainable."
Rapid Algae Farming (RAF) is a low cost, highly adjustable technology for growing algae in both indoor and outdoor environments. Indoor RAF is a viable technology for controlled growth environments that will enable low cost algae cultivation for smaller scale algal based processes. This will ultimately lead to outdoor RAF, which is being developed for the large scale operations needed for algae based fuels, plastics and chemicals. The key features of RAF are:
* Low manufacturing costs
* Streamlined installation with quick turnaround times from first ground breaking to full algae production
* A range of features from manual to highly automated operation
Technology has been developed and demonstrated for separating suspended algae out of solution that dramatically reduces energy consumption by utilising surface physics and capillary action. Harvest, dewater, and dry (HDD) improves the economics of algae-based bio-fuel production, and removes a major barrier to large-scale commercialisation of this renewable alternative fuel source. Furthermore, this technology holds the potential to revolutionise the removal of solids from dilute solutions in a wide range of industries.
HDD consists of two belts moving in opposing directions. Solution containing the desired solid is poured through a spout on to the top belt, which is moving from left to right on the schematic. Water passes through the belt, while the solid remains on top. A capillary belt moving in a countercurrent direction passes directly underneath the first belt. The capillary belt is wetted and helps draw the water through the top belt using liquid adhesion. The concept for HDD was influenced by web-fed plastic processing.
ALGAE AS A RAW MATERIAL
The purpose of this technology is to contribute towards solving two environmental problems: algal proliferations and the elimination of plastic waste. The biomass created by green algae and Zostera plague could generate profit by being exploited as a raw material for the production of a new generation of functional bio-plastics and bio-composites for different applications. Methods for assessing biodegradability and bio-recyclability of algae-derived bio-plastics and bio-composites are to be evaluated, and standard test systems developed.
Cultivation of algae to produce long chain polymers having flocculating properties is disclosed. Algae are cultivated in an aqueous nutrient medium until relatively high culture densities are achieved and thereafter under conditions in which the cells become deficient in nitrogen thereby causing the cells to shift from a growth phase in which protein production predominates to a growth phase in which extra-cellular polymer production predominates. An adequate supply of other nutrients as well as CO2 and light are maintained in the culture medium during the latter phase to insure that a change in cell metabolism is produced by a deficiency in nitrogen. The algae then produce high molecular weight polymers exhibiting strong flocculating activity.
Scientists worldwide are striving to develop thin, flexible, lightweight, inexpensive, environmentally friendly batteries made entirely from nonmetal parts i.e. algae. Among the most promising materials for these batteries are conducting polymers.
There is a long hoped to find some sort of constructive use for the material from algae blooms and have now been shown this to be possible with a nanotechnologist. This creates new possibilities for large-scale production of environmentally friendly, cost-effective, lightweight energy storage systems. The new batteries consisted of extremely thin layers of conducting polymer just 40 to 50 nanometers or billionths of a meter wide coating algae cellulose fibers only 20 to 30 nanometers wide that were collected into paper sheets. They could hold 50 to 200 per cent more charge than similar conducting polymer batteries, and once better optimised, they might even be competitive with commercial lithium batteries, the researchers noted. They are also recharged much faster than conventional rechargeable batteries - while a regular battery takes at least an hour to be recharged. The new battery also showed a dramatic boost in the ability to hold a charge over use. While a comparable polymer battery showed a 50 per cent drop in the amount of charge it could hold after 60 cycles of discharging and recharging, the new battery showed just a six per cent loss through 100 charging cycles.
When you have thick polymer layers, it's hard to get all the material to recharge properly, and it turns into an insulator, so you lose capacity. When you have thin layers, you can get it fully discharged and recharged. Batteries made of paper may power electronics in the future, researchers say.