Frequently Asked Questions
Why do you use algae instead of corn for plastics?
Algae represents a sustainable non-food based plant protein that can exhibit thermoplastic properties like other plant proteins. However, since algae is considered a nuisance and wasted by-product, it improves the environmental and economic impacts of using food crops for biobased products.
How does algae clean water?
Algae cells absorb nutrients such as nitrates, phosphates, and carbon dioxide during photosynthesis. These nutrients are used to metabolic process and are converted into plant biomass and oxygen by light induced photosynthesis.
Why does algae and fish grow together?
Algae cells feed off the nutrients and waste given off by growing fish. In aquaculture, the fish stocking density of ponds is usually higher than what is found in nature. The large amount of nutrients in the ponds makes them fertile for algae blooms. Therefore, to sustain these dense populations, the algae blooms need to be controlled and not crash the ponds. Pond crashes can occur when algae cell populations gets so dense that during nighttime when there is no light, nor photosynthesis, the algae cells begin respiring and consuming oxygen. The algae respiration, much like the fish respiration, can consume the oxygen in the pond causing anoxic zones and suffocate the fish in the pond. Therefore, there must maintain a balance between the fish and algae populations in the pond to sustain a viable ecosystem.
Why is algae based water treatment systems better than conventional oxidation water treatment?
Algae based water treatment systems can use either open or closed cultivation systems. In the case of complete waste water treatment, an open system is best suited. The open pond algae water treatment systems have primary, secondary and tertiary treatment integrated into an advanced algae pond design. In the first stages, there is a combination of microbial activity, including anaerobic digestion and oxidation occurring that breaks down organic compounds down into smaller inorganic compounds. These compounds are things like ammonia, nitrates, nitrites, phosphates, and carbon dioxide. The open pond algae water treatment system uses sunlight, carbon dioxide and the nutrients from wastewater to grow and remediate the water.
The open algae based water treatment systems use a simple land based ponding system that is a lower capital expense that conventional oxidation water treatment systems. Also, the energy cost of using algae to produce oxygen and absorb these nutrients is significantly lower than using higher energy blowers or aerators. The personnel cost is also significantly less, only requiring one or two operators to run the system. Lastly, the algae water treatment process produces a valuable co-product, i.e. protein rich algae biomass, as a result of absorbing these waste nutrients. The algae biomass can be used for other commercial applications providing some additional revenue to the operation.
How does algae become a plastic?
Algae biomass can have a composition that varies depending on the cultivation techniques, species and nutrients available during the growth phase. In nutrient rich conditions found in wastewater treatment, and aquaculture, the algae biomass is dominated by the protein fraction. The plant protein found in algae, like other plant proteins, exhibits interesting properties when thermomechanical forces are applied to the material. By definition, protein is comprised of polymer chains of amino acids. Thus, by applying these thermomechanical forces, the protein chains are denatured (hydrogen bonds broken), deformed and stretched out in the orientation of the mechanical forces. In an extrusion process, the deformation and stretching allows the algae cells to deform and stretch and become elongated and entangled with the thermoplastic base resin. In the image below, you can see the transformation of distinct algae cells on the left melting together and becoming a homogeneous plastic like material on the right.
What kind of plastics can be made with algae?
Algae can be blended with wide variety of base resins, where the final resin has properties similar to that of the base resin. Therefore, depending on the base resin used, the final product can offer a wide range of material properties from very stiff and rigid plastics, to very flexible and elastomeric plastics. The Solaplast resins are comprised of 45% algae, but can be increased or decreased depending on the type of base resin and the desired end application.
The types of products made from these Solaplast resins can be produced using injection molding, extrusion and 3D printing. Thus, any type of product made with resins such as PP, HDPE, EVA, HIPS, PLA and PBAT, for example, can be made with a respective grade of Solaplast resin.
The limitations of the Solaplast resins are currently clear plastic (Solaplast resins are opaque and/or pigmented), food contact (not FDA approved yet), and are slightly hydroscopic (absorbs small amounts of moisture over time depending on the algae loading level).
Are all algae resins biodegradable?
No. Only Solaplast resins grades marked as compostable are considered biodegradable. This is because with the durable series of resins, such as the Solaplast 1000 series, the base resin used is a non-biodegradable plastic. Therefore, even though the algae fraction blended with a non-biodegradable resin may be biobased and biodegradable, once the algae is blended with the conventional plastic, the finished product cannot claim biodegradability because the conventional plastic fraction will not degrade rapidly like the algae. In this case, we focus more on durable resins for carbon fixation, where we can lock in nutrients and carbon dioxide into the plastic for longer term carbon sequestration.
Where does the algae that ALGIX uses come from?
ALGIX has secured supply agreements with several algae producers including waste water treatment, aquaculture and ecological blooms. In some of these cases, ALGIX buys the dry algae biomass directly from the producer. In other cases, ALGIX is involved in the direct harvesting, drying and transporting of the dry algae to the Solaplast factory.
What is the value of algae biomass?
Algae biomass can offer a wide range of value depending on the compositional analysis of the feedstock. In the premium case, the algae is grown for nurtracuetical applications where the high value pigments or oils are extracted and sold for human or animal consumption. In these cases, the value of the algae biomass can be very high depending on the high value metabolites concentration in the material.
In biofuels, the algal oils are desired, and the growth conditions are modified to promote more oil or lipid content. In this case, the algal oils for biofuels are on par with conventional fuel products, such as diesel, gasoline or jet fuel. The value of these products are based on the commodity markets for fungible fuels.
In the case of algae for bioplastics, the value is calculated based upon the protein and mineral content of the algae feedstock. The protein is a value attractor, meaning that the higher the protein content the more valuable the material is. However, if the material has more mineral or ash content in it, this serves as a value detractor and reduces the value of the biomass. Thus, more protein more value, more mineral/ash less value. The protein value is set by comparing the algae protein meal to the conventional commodity traded crop meals, such as corn meal and soybean meal.
What differentiates bioplastics from conventional plastics?
The term bioplastics encompasses a whole family of materials that differ from conventional plastics in that they are biobased, biodegradable, or both. So what’s the main difference?
Biobased means that the material or product is (partly) derived from biomass (plants or algae). Biomass used for bioplastics stems from e.g. algae, corn, sugarcane, or cellulose. The term biodegradable refers to a chemical process during which micro-organisms, that are available in the environment, convert materials into natural substances such as water, carbon dioxide and biomass (artificial additives are not needed!).
The process of biodegradation depends on the surrounding environmental conditions (e.g. location or temperature), on the material itself, and on the application. Biodegradability is an inherent property of certain bioplastic materials that can benefit specific applications (e.g. biowaste bags or service ware).
Where to find bioplastics?
Bioplastics already play an important role in the fields of packaging, agriculture, gastronomy, consumer electronics and automotive to name a few.
In these market segments, bioplastic materials are used to manufacture products intended for short term use, such as mulch films or catering products, as well as durable applications, such as mobile phone covers or interior components for cars.
Why use bioplastics instead of plastics?
Bioplastics are driving the evolution of plastics. There are two major advantages of biobased plastic products compared to their conventional versions:
- They save fossil resources by using biomass which constantly regenerates
- Provides the unique potential of carbon neutrality.
Furthermore, biodegradability is an add-on property of certain types of bioplastics. It offers additional means of recovery at the end of a product’s life.
With a production of 280 million tonnes, plastics are a necessity in today’s economy. Normally they are produced from crude oil products. Many of the materials utilized to date can, however, also be made from renewable resources.
In recent years, the face of the plastic industry has begun to change. Numerous biobased plastic materials have been developed and today represent a proven alternative to their conventional counterparts. Roughly 85 percent of plastics could technically be substituted with biobased plastics. Bioplastics offer a broad range of functionalities optimized for each type of application and, in addition, can reduce the impact on the environment.
Bioplastics can also be processed into a vast array of products using conventional plastics processing technologies. The process parameters of the processing equipment simply have to be adjusted to the individual specification of each bioplastic type.