Pilot-scale assessment of twin-screw extrusion combined with lime pretreatment to improve semi-continuous biomethane production from corn stover, and potential of produced digestate as fertilizer.

This study investigated the effect of lime pretreatment coupled with twin-screw extrusion on corn stover to improve anaerobic digestion at pilot-scale. The extrusion pretreatment was successfully optimized at pilot-scale with limited energy consumption of 537 W h/kg DM and water losses at 6%. Extrusion followed by lime impregnation resulted in 14% total cellulose, hemicelluloses and lignin depolymerization, increase of specific surface area by a factor of 5, and particle size reduction up to 16%.

Chemical composition and mesophilic anaerobic digestion of commercial compostable food packaging: Implications for bio-waste management.

This study assessed the chemical composition and mesophilic anaerobic biodegradability (BI) of 34 commercial compostable food packaging products, including sixteen bags, twelve coffee capsules, and six other products (cups, forks and straws). Thermogravimetric analysis and spectroscopy techniques allowed to determine the proportions of polymers (PLA, PBAT, PBS, PHBV, PE, cellulose, and starch) and additives (inorganic and organic). Six compositional clusters were identified: PHBV-based products (BI = 92 ± 1 %), cellulose-based products (BI = 85 ± 9 %), PLA-based products (BI = 30 ± 20 %), PBAT/starch-based bags (BI = 25 ± 8 %), PE/starch-based bags (BI = 9.

Anthropogenic Fingerprint Detectable in Upper Tropospheric Ozone Trends Retrieved from Satellite.

Tropospheric ozone (O) is a strong greenhouse gas, particularly in the upper troposphere (UT). Limited observations point to a continuous increase in UT O in recent decades, but the attribution of UT O changes is complicated by large internal climate variability. We show that the anthropogenic signal ("fingerprint") in the patterns of UT O increases is distinguishable from the background noise of internal variability.

Ozone-related acute excess mortality projected to increase in the absence of climate and air quality controls consistent with the Paris Agreement.

Short-term exposure to ground-level ozone in cities is associated with increased mortality and is expected to worsen with climate and emission changes. However, no study has yet comprehensively assessed future ozone-related acute mortality across diverse geographic areas, various climate scenarios, and using CMIP6 multi-model ensembles, limiting our knowledge on future changes in global ozone-related acute mortality and our ability to design targeted health policies. Here, we combine CMIP6 simulations and epidemiological data from 406 cities in 20 countries or regions.