South Australian company ByGen (Adelaide, Australia) has expanded its focus on activated carbon from using sources such as agricultural wastes to now include plastics. The company has successfully made activated carbon from several types of polymers, including contaminated plastic waste.
ByGen co-founder and CEO Lewis Dunnigan, PhD, said he believed the breakthrough made with co-founder/CTO Ben Morton was the first conversion of its kind in the world.
Dunnigan and Morton established a pilot plant last year at the University of Adelaide where they’ve experimented with a variety of widely available agricultural wastes including almond shell, sawdust, grape marc and rice husks to produce high quality activated carbon.
The scientists considered that plastics contain a high level of carbon.
“There’s a big problem with contaminated plastics globally, and we think making activated carbon from it could be a good way to remedy that,” Dunnigan said. “Because we’re both scientists, we noticed some fundamental similarities between agricultural wastes and plastics. Agricultural waste has a high carbon content, as does plastic, so the idea occurred to us ‘why not make activated carbon out of plastic?’”
Activated carbon has a variety of industrial uses, including purifying liquids such as drinking water, food and beverage processing, odor removal, contaminated soil remediation and gold processing.
It is traditionally made from coal, hardwood or coconut shells and sells for about A$2,000/US$1,380 a tonne.
“Traditionally you have to make it at about 1,000 degrees, using steam or harsh chemicals,” explained Dunnigan. “We felt like the energy intensive processes in developing countries with non-renewable feedstocks weren’t sustainable, so we tried lots of different Australian agricultural wastes and came up with the ByGen process.
“We’ve proven we can make high-quality activated carbon from plastics and also generate a lot of heat at the same time, more so than with agricultural waste,” Dunnigan said. “Heat can be a valuable bi-product for industries like brick making, cement production, and industrial drying processes. One tonne of plastic generates 3-5MW of heat, which is quite a lot; enough that this could even be converted to electricity or exported to the grid.”
|ByGen co-founders Ben Morton and Lewis Dunnigan.|
The ByGen process is significantly less energy intensive with quality and yields in-line with existing technologies; four tonnes of agricultural waste produces approximately one tonne of activated carbon, with a value of up to A$2,500/ US$1,724 a tonne.
ByGen was focusing on the areas of water purification and soil remediation, and has also worked with prospective customers to tailor the carbon specifically to their end uses, Dunnigan reported.
“The feedback is ongoing, but the test results show that the quality of the carbon we make is at least comparable to what is already on the market,” he said.
The company is now looking for an industry partner in the plastics sector to develop the technology further and take it to market. Dunnigan said it was hoped the latest round of capital raising would be completed by May next year with construction of the new plant beginning shortly afterwards.
PlasticsToday found that, according to a Grand View Research study released in May, the global activated carbon market size was estimated at $4.7 billion in 2018 and forecast to expand at a CAGR of 17.5% during 2019-2025. A regional benefit for ByGen's technology is that Australia is a currently a net importer of the material.