We live in the times when world faces challenges like climate change, population growth, increasing global energy demand as well as possible shortage of fossil resources. These challenges force us to seek possibilities for shifting from oil-based to bio-based resources for energy and materials production. In this perspective, biorefinery concept is seen as the key to implement a future environmentally friendly sustainable biomass-based economy.
Nowadays, biorefineries are widely considered to be a promising route to deliver a spectrum of products and bioenergy in a more sustainable way. Biomass is acknowledged as the main foreseeable sustainable alternative feedstock of organic fuels, chemicals and materials to replace non-renewable raw materials in future. In order to tackle global challenges and to minimize the impacts on the food and fodder markets, development and implementation of new biorefinery processes utilizing natural non-food lignocellulosic resources such as wood and straw is of particular interest to us.
Is the idea of biorefinery new?
Definitely not! The concept of utilizing biomass as feedstock for wood-based construction materials, pulp and paper, fuel and chemicals is not new and has been known for centuries already.
However, modern advanced biorefinery concepts aim at valorizing a wide variety of biomass—from forestry, agriculture, and algae as well as biomass residues—into a broad range of bioproducts and bioenergy with reduced environmental impact compared to the fossil-based products.
Sounds promising, but why still so few novel commercial plants?
Even though the basic approach to the production of chemicals and transportation fuels from biomass is well known, tens of new advanced technologies for bioproducts and bioenergy are still under development, showing different levels of maturity.
Many developers face certain challenges on the way to commercializing a new bio-based process which looks highly promising on the laboratory scale. These challenges are mainly related to the economical, technical and sustainability features of the process. It is obvious, that for successful technology implementation it is not enough that process utilizes biomass and residues as feedstock. In addition to being bio-based, the new process should be proven to be environmentally friendly and economically feasible. The bioproduct must be competitive, so its quality and market price should be at least similar or improved compared to a product from conventional process.
What are the most common technical, economical and environmental challenges on the way to bioprocess establishment?
It should not surprise that all these challenges are very closely interconnected.
The technical challenges are usually associated with chemically diverse and varying raw material properties. Non-uniformity of biomass requires a search for an optimal sequence of process steps to obtain improved yield and properties of the valuable end-products in the most efficient way. In some cases, modern biorefinery process developers concentrate on the process leading to the main product, not paying attention to side products and side streams, especially process effluents. The process parameters may not be optimized in relation to the chemicals and energy consumption. Nevertheless, these secondary flows have significant impact on the valuable product’s manufacturing cost. Careful process design will significantly improve the economic feasibility of the process by optimizing the equipment, heat and water recovery, minimizing the energy and chemicals consumptions.
At the same time, closing loops of streams, for example recovery of heat and chemicals, is essential for a process to be commercially profitable and it also reduces the load to the environment by decreasing the emissions to water and atmosphere and by generating less process waste.
What can be done to overcome the challenges?
To ensure environmentally friendly, economically feasible and sustainable use of biomass, the cascading approach should be considered in every new biorefinery. In the cascading approach, the most valuable products are made first, then the side streams are utilized to produce second product and so on, leaving the process residues for producing bioenergy and biofuels. This approach increases resource efficiency by adding value to biomass feedstock as part of bioeconomy. Alternatively, the new process should be easy to integrate to existing facilities thus improving the efficiency of feedstock utilization.
Especially when developing new technologies, skilled engineering is required to understand the fundamentals, improve safety and availability, optimize material and energy efficiency and improve profitability in the current and subsequent process phases. Here at Sweco we have all the necessary expertise from early pre-feasibility analyses all the way to detail engineering and site assistance to help our customers during development of their bioproducts and biorefinery process to meet the future-circular world’s demands.
Olga Ershova, Bio process specialist, Sweco