Bioplastics from pulp and paper side streams

The world is flooded with plastic and even scientists are comparing the balance of plastic trash versus fish in the oceans. However, plastic can come in many forms. There is technology to transform wastewater into biodegradable bioplastics. Alan Werker is one of those who work to help industrialize production of such biobased renewable resources.

Plastic is a major problem for the environment and several projects around the world look for solutions with new management practices and alternate biobased materials. One project is MultiBio; a collaborative project in Sweden where side streams from pulp and paper mills is offered new life and circularity through conversion into biodegradable products.

Many participants work together

The project looks to evolve ideas where independent processes are combined in a cascade and by-products become inherent raw materials in a new production process.

One of the participant researchers is Alan Werker, an environmental engineer and specialist in biological treatment. He grew up in Canada, where his doctoral thesis focused on purification processes and toxicity removal for forest industry wastewaters.

“When purifying water, waste sludge is produced. The sludge contains interesting bacteria that can convert pollutants into useful/attractive polymers if fed properly”.

These polymers are natural polyesters called PHAs (polyhydroxyalkanoates) and they are building blocks that can be processed into biodegradable bioplastics.

Bioplastics concepts throughout the world

Alan Werker has for many years devoted himself to developing a working concept. In 2017, he and his colleague Simon Bengtsson, started the company Promiko. They collaborate with specialists and academic groups and participate in projects around the world that support biobased developments. For example, they collaborate with research groups and companies in Sweden, the Netherlands, Australia, Portugal, and Italy. In the Horizon 2020 project Scalibur, work continues to produce bioplastics and other renewable resources from Dutch municipal organic waste.

Technology are being evaluated at the mills

In MultiBio, practical tests have been performed at mills in the region Värmland.

“We make assessments of mass balances, and the existing waste management practices and evaluate steps to integrate the production of biopolymers as a by-product from the existing treatment processes”.

For Alan, it is fascinating to delve into the depth of the bioprocesses and understand ways to utilize the interesting properties of these biopolymers in applications including bioplastics.

“It is a great advantage to work in real industrial processes and gain insight into challenges but also opportunities that are possible for the mills”.

85 million PET bottles 

MultiBio is about applying the ideas for the benefit of the forestry industrial sector. To motivate developments forward with eyes wide open and to find the niches that can work in practice.

“For the future, we look for the road that makes the production of PHA economically sound, and that products and services from these polymers, that we cannot possibly know or anticipate today, will be developed. Each mill could produce between one thousand and three thousand tons of PHA per year just on the mill organic waste. Raw material that could, for example, be used for environmentally friendly multilaminates, coatings or composite materials for the pulp and paper industry”, says Alan Werker.

To give a sense, 2,000 tonnes of PHA polymer equals approximately 85 million 1/2-liter PET bottles.

Bioplastics with many advantages

PHA based bioplastics can have many advantages over oil-based plastics. Biodegradability in nature can be tuned and this can form part of the material function in, or after, service. Another benefit to the environment is that it is a renewable resource. But Alan does not believe that PHA based plastics are a solution to the whole big global plastics problem, far from it. There are far too many types and uses of plastic but PHA does have a role to play in a biobased society.

He does not anticipate that it will be possible to replace all plastic in the world with bioplastics. The plastics we use today are excellent materials and hard to do without in many cases.  Products and services with plastics need to be delivered in improved ways that avoid environmental impact.

“The best applications for PHAs are those that exploit unique properties of this polymer compared to others. PHA could supplant other polymers in some applications. However, it becomes more interesting if the polymer has a duality of function, like conversion into biogas for energy after the product is thrown away”.

What do you think about the future of the biobased industry?

“I hope that more projects will be started where we help industry and municipalities to create opportunities by converting waste into renewable raw materials. It is a development that is favorable to society and gives meaning”.

Facts

Twelve stakeholders participate in MultiBio such as the pulp- and paper mills BillerudKorsnäs, Stora Enso and Rottneros, the cluster organization Paper Province, Karlstad University, Lund University and RISE Research Institutes of Sweden.

More photos can be downloaded here>

 

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