This Small Business Innovation Research Phase I project will use waste methane gas (biogas) as a feedstock to produce pellets of polyhydroxyalkanoate (PHA), a valuable polymer that is converted into a variety of eco-friendly plastic products such as children?s toys, electronic casings, water bottles, and food packaging. The current plastics market is dominated by traditional petroleum-derived, non-biodegradable, energy-intensive plastics. Alternative plastics are derived from rapidly renewable biological resources (biobased) and consumed by microbes when no longer needed (biodegradable). Unfortunately, these alternative plastics are often costly and energyintensive to produce. The company has a novel, energy-efficient method to produce a biodegradable, biobased plastic at a cost competitive with petroleum-based plastics. Phase I will assess the feasibility of this novel process for full-scale commercial production using biogas from a wastewater treatment plant. The main objective is to achieve stable-operation and increased bioplastic production through optimization of parameters including biological yields, rates, and costs at the Phase I scale. This optimization will result in the production of bioplastic from waste biogas at a price competitive with petroleum-based plastics.
The broader impact/commercial potential of this project will ultimately be the widespread production of low-cost bioplastics from waste biogas and the eventual displacement of petroleum-based plastics. Bioplastics have the potential to capture an increasing fraction of the plastics market, thereby giving consumers the choice to purchase affordable, environmentally friendly, bioplastic-based products. When bioplastic products produced by the company are disposed in modern wastewater treatment plants or landfills, they biodegrade anaerobically (without oxygen) to methane. This methane can be cycled back and reenter the process as feedstock to produce more PHA. Thus, the life cycle may be closed, creating a ?cradle to cradle? system. This use of biogas will provide a strong economic incentive for facilities to capture their methane, rather than releasing or flaring it, which will reduce greenhouse-gas emissions and reduce corresponding impacts on global warming. The innovation will enhance scientific understanding by studying the production of bioplastic from waste biogas and by characterizing the microbial species responsible for this conversion. This project represents one of the first times that waste biogas will be used commercially to feed a community of bacteria to produce a valuable product.
Mango Materials produces biobased, biodegradable plastics from waste biogas (comprised mostly of methane) that are economically competitive with petrochemical-based plastics. Biogas is readily available at wastewater treatment plants, landfills, and other industrial and agricultural sources. The Mango Materials process begins with waste biogas that is consumed by bacteria to create a valuable and cost-competitive product, the biopolymer polyhydroxyalkanoate (PHA). Conventional methods of producing PHA use sugar feedstocks, which involve significant energy to grow, harvest, and ship to polymer production facilities, in addition to requiring the creation of special bacteria to consume the sugar feedstock. The Mango Materials process has numerous environmental benefits, including (1) use of a greenhouse gas as feedstock, (2) a less energy-intensive process, and (3) production of a biobased, biocompatible, completely biodegradable product. The novel Mango Materials PHA manufacturing process will increase the amount of environmentally friendly, non-toxic polymer on the market. As part of the National Science Foundation SBIR grant, Mango Materials carried out various studies over different scales, to test PHA production using waste biogas from a wastewater treatment plant. The first study Mango Materials performed validated that bacteria given waste biogas produced about the same amount of PHA as bacteria given pure methane gas as a feedstock. As part of this study, the composition of the naturally occurring bacteria community was monitored over time. The results of this investigation are significant because it further proves that Mango Materials can produce an inexpensive biodegradable plastic by using waste biogas. Mango Materials also performed another investigation to prove that the process could be scaled up effectively. The second study took place on-site at a wastewater treatment plant and involved the continuous feeding of unfiltered biogas to a bioreactor. At the end of this study, Mango Materials was able to confirm that PHA could be produced from waste biogas even with no pretreatment of the biogas while obtaining relevant operating parameters, which has positive implications for commercialization. Mango Material’s proprietary technology of making biodegradable plastic has been proven to not only work, but to also be feasible across multiple scales. Once scaled up further, this process will be able to produce biodegradable plastic that is competitively priced with petrochemical-based plastics, and will be available in large quantities for consumer use. In addition to making a replacement for petrochemical-based plastics, Mango Materials reduces greenhouse gases by using waste biogas as a feedstock. Overall, Mango Materials solves three environmental issues with the reduction of greenhouse gases, preservation of energy within the system, and production of a biodegradable plastic, making this product genuinely environmentally friendly.
