Life cycle assessment of an efficient biomass power plant supported by semi-closed supercritical CO₂ cycle and chemical looping air separation

Biomass power plant with carbon capture facility has great carbon emission reduction potential due to biomass's carbon neutrality characteristic, but it has been long-time suffered from undesirable system efficiency. This paper explored the life cycle carbon emission of a high-efficient biomass power generation system, which was comprised by the semi-closed supercritical CO2 cycle and chemical looping air separation sub-units. This system was proved to be environmentally superior with the life cycle warming impact value at 97.69 kg CO2 eq./MWh, the life cycle carbon emission reduction rate was 49.61 % and 45.46 % compared with traditional biomass gasification combined cycle system and biomass chemical looping gasification combined cycle system, respectively. The fuel and materials preparation stage should receive improvement attention due to its largest emission share of 76 %. In addition, the effects of key parameters, such as CO2 to biomass ratio (CO2/C), biomass gasification temperature, oxygen carrier and biomass types on environmental performance were investigated to further reveal this system's carbon emission reduction potential. The biomass/coal co-fired system showed net zero carbon emission was achieved when biomass share exceeded only around 10 %.