How Efficient Mixing can Contribute to a Circular Economy
Emergence of a new market - bio-based polymers
The development of processes for the production of basic materials for the chemical industry based on biomass has three main objectives:
- Use of renewable raw materials to reduce greenhouse gas emissions and combat climate change
- Development of a "sustainable" circular economy
- Reduce the dependence of the chemical sector on fossil raw materials (oil, natural gas,...)
Although the market for bio-based products is still in its infancy, it is currently experiencing strong growth due to the following factors:
- Increasing consumer interest in more sustainable consumer products
- Increased efforts by industry and brand manufacturers to offer bio-based packaging materials
- The resolution of a potential supply shortage of olefins and some high-demand aromatics, encouraging the use of new raw materials and new production processes
What are the Challenges for Large-Scale use of Bio-Based Chemistry?
- Production costs compared to petroleum-based processes
- Access to renewable resources
- The development of utility sectors
- The construction of biorefineries that exploit synergies between different biomass conversions, for example between biofuels production and bioproducts
- The development of new biobased products
- The market remains highly dependent on key economic and political factors, such as oil price changes, which are likely to favor or not the development of production capacity for biobased intermediates
- The absence or, conversely, the introduction of public and regulatory incentives
Process Chains for the Production of Bio-Based Polymers - the Biorefinery
The so-called «biorefinery» is developing as an alternative to the classic petrochemical processes, mostly based on naphtha or natural gas. The original processes of the biorefinery were mainly based on sugar as the starting product – and were therefore in competition with the production of food and animal feed. More modern processes, so-called second-generation bioprocesses, aim to utilize almost all components of regenerative raw materials, i.e. as many or even all plant components as possible.
The analogous idea has been the basis of oil refineries for decades, which is why the basic concept of the biorefinery is based on the established chemical processes of petrochemistry. In the first step of a biorefinery, the biomass is subjected to physical material separation. The main and by-products are then subjected to microbiological and/or chemical conversion reactions and thermal processes.
A biorefinery based on lignocellulose can be considered as an example. This uses naturally dry raw materials such as straw, grass, forest residues or cellulose-containing waste from the paper industry as the starting product. On this basis, products are produced in three different lines: Adhesives, binding agents, fuels or chemical products can be produced in the lignin line. Thickeners and xylose derivatives, such as nylon, can be produced in the hemicellulose line. And in the cellulose line, fermentation products such as ethanol or lactic acid are obtained from glucose, from which polylactic acid (PLA) can be produced.
Production and Purification of Bio-Based Monomers for Further Processing into Biopolymers
Aerobic fermentation plays an important role in the production of bio-based platform chemicals or monomers. The stirred large-scale fermenter is a highly efficient process solution, especially in terms of mass transfer, heat transfer and the yield and product quality that can be achieved as a result. Subsequent to the production of these bio-based monomers, they are purified, which often happens in a crystallization step. At the end there is the polymerization or polycondensation to the bio-based polymer.
EKATO not only offers the right agitators for all these different process steps, but also supports you both in the process development of the individual manufacturing steps and in the engineering of complete agitated reactor systems.
Some bio-based polymer products such as polylactic acid (PLA) or other polyesters have already reached market maturity or are already on the «home stretch» of process development. In order to promote independence from fossil feedstocks – and, of course, to meet challenging climate targets – many biobased products and their manufacturing processes will grow to industrial scale in the coming years. The safe scale-up of these processes and the energy efficiency of the individual process steps are of key importance.
In the context of these developments and adaptations of new technologies, modern agitation and mixing technology of EKATO can make a significant contribution.