The 6th International Conference on Biomass Energy (ICBE2018)

441 / 2018-09-01 17:04:37

Options for integrated biochar-bioenergy systems as negative emission technologies

Plenary track > A. Policies & Strategies

Biochar’s potential to store atmospheric carbon has been estimated to be 0.7-1.8 Gt CO2-C(eq) yr−1. This presentation will focus on ways to achieve or increase this potential, while maximizing positive and minimizing potential negative environmental and economic impacts. In the first part the potential to integrate biomass pyrolysis into bioenergy systems and negative emission technologies concepts with the aim to boost their performance in respect to reduction of greenhouse gas emissions and profit will be discussed. While pyrolysis as a standalone technology has been under development and use for a number of decades, focussing on bio-oil production and waste management, its integration into biorefineries is a more recent concept. This presentation will discuss different options and provide specific examples of ways to integrate pyrolysis with other thermochemical or biological systems into a zero-waste biorefinery, examples of which are schematically shown in Figure 1. Specific examples of benefits of such integration include:
1) Increased yield of methane and improved stability of AD reactors, our results showed that certain types of biochar can be used to control ammonia inhibition in AD reactors and to increase methane yield.
2) Upgrading of low-value aqueous fractions of pyrolysis liquids into methane or volatile fatty acids in AD reactors. We showed that while the organic fraction of bio-oil contained too many inhibitors to allow AD decomposition, the aqueous fraction could be successfully converted.
3) Beneficial utilisation of mineral-rich residues from marine biomass utilisation, offering controlled release of nutrients into soil or growing media, such as K and P. Our results showed that most of the minerals are available, and their release dynamics can be controlled by adjusting pyrolysis conditions.
4) Use of waste lignin for co-production of biochar and other products