An Analysis of the Potential and Cost of the U.S. Refinery Sector Decarbonization.

In 2019, U.S. petroleum refineries emitted 196 million metric tons (MT) of CO2, while the well-to-gate and the full life cycle CO2 emissions were significantly higher, reaching 419 and 2843 million MT of CO2, respectively. This analysis examines decarbonization opportunities for U.S. refineries and the cost to achieve both refinery-level and complete life-cycle CO2 emission reductions. We used 2019 life-cycle CO2 emissions from U.S. refineries as a baseline and identified three categories of decarbonization opportunity: (1) switching refinery energy inputs from fossil to renewable sources (e.g., switch hydrogen source); (2) carbon capture and storage of CO2 from various refining units; and (3) changing the feedstock from petroleum crude to biocrude using various blending levels. While all three options can reduce CO2 emissions from refineries, only the third can reduce emissions throughout the life cycle of refinery products, including the combustion of fuels (e.g., gasoline and diesel) during end use applications. A decarbonization approach that combines strategies 1, 2, and 3 can achieve negative life-cycle CO2 emissions, with an average CO2 avoidance cost of $113-$477/MT CO2, or $54-$227/bbl of processed crude; these costs are driven primarily by the high cost of biocrude feedstock.

Surgical treatment of acute recurrent throat infections in children.

OBJECTIVE: The purpose of this study was to define the contribute of surgery and watchful waiting in the treatment of feverish episodes and other clinical manifestations related to acute recurrent throat infections in children. METHODS: An observational, retrospective and multi-centric study was carried out on 407 subjects, aged 2-11, with a minimum two-year follow-up. Chi square test and Fisher's test were used for the statistical analysis. RESULTS: Watchful waiting prevented, similarly to surgery, recurrences of feverish episodes, but did not favourably impact on other clinical manifestations (respiratory obstruction, otitis media, group A beta hemolyticus streptococcus positive laboratory findings) as compared to surgery (p<0.001). CONCLUSIONS: The higher effectiveness of surgical treatment, as compared to watchful waiting, was documented in the study patients, considering all the clinical manifestations related to acute recurrent throat infections.