Production of high added value bio-products from woody biomass applying thermo-chemical technologies improved by microwave heating.
Forests fires represent one of the most severe disruptions in all Mediterranean areas and numerous factors contribute to the origin of such fires. Some of these are related to climate change and global warming, but some are also related to the accumulation of biomass in forestry areas. Fire prevention is currently a significant expense for administrations and forestry clearance activities are not sufficient for the extensive areas that require silvicultural activities. Current activities in the relatively new high-density forest mass leave extracted biomass on the forest surface. This biomass largely consists of shrubbery and conifers and there is no use for this waste material.

Biomass waste is considered as the main renewable source for the production of fuels and raw materials for the manufacture of chemicals with high added value. These biomass wastes can be broken down by thermochemical processes such as pyrolysis. Pyrolysis is a thermal degradation process in the complete or partial absence of oxygen. Under these conditions biomass is converted by a cracking process into a liquid fraction, a gas phase that is mainly composed of non-condensable gases such as H2, CO, CO2 and CH4, and a solid fraction known as biochar.

Administrations, forest clearance companies, stakeholders related to the agricultural sectors and chemical companies are beneficiaries of this GP.

Resources needed

The development of the process required a multidisciplinary team of experts in different fields; chemical and mechanical engineering, microwave technology, analytical chemistry and others. There was important funding from public (ERDF) and private sources to scale up the process (600.000€ approx).

Evidence of success

- Implementation of two continuous pilot plants (1 kg/h and 1 ton/h) to turn biomass wastes into bio-products by microwave irradiation.
- Around 6000 kg of forest wastes treated since the implementation of the GP.
- R&D projects developed to assess the potential applications of the bio-products. Biochar is used as biofertilizer and the aqueous fraction is being studied as bio-herbicide to replace glyphosate, a carcinogenic substance.
- Publication of scientific papers.

Difficulties encountered

One of the challenge encountered during the implementation of the GP was the scale-up of the process but it was solved successfully.It is necessary to continue working on the promotion of the bio-products to enhance their utilisation within the bio-based circular economy framework.

Potential for learning or transfer

The production of bio-products from forest wastes is related to the sustainable use of biomass and contributes to the construction of a bio-based circular economy. It links the fight against climate change with forest use, and so it encourages the development of forest cleaning activities for fire prevention. Thus, wastes that are currently discarded and burned will be turned into valuable resources. This will result in the reduction of forest fires and, therefore, in the reduction of greenhouse gases emission.

This GP promotes the implementation of biorefineries based on thermochemical processes and the use of bio-products contributing to the circular economy model and the development of rural areas.
Some companies within the agricultural and weed prevention sector have shown their interest in the application of the bio-products obtained.

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Main institution
Chair of Environment (University of Alcala), Cátedra de Medio Ambiente (Universidad de Alcalá)
Andalucía, Spain (España)
Start Date
December 2014
End Date


María Caberta Please login to contact the author.