Equilibrium model analysis of waste plastics gasification using CO2 and steam

Utilization of carbon dioxide (CO₂) in thermochemical treatment of waste plastics may significantly help to improve CO₂ recycling, thus simultaneously curtailing dioxins/furans and CO₂ emissions. Although CO₂ is not such an effective gasifying agent as steam, a few investigations have explored the utilization of CO₂ in conjunction with steam to achieve somewhat higher carbon conversion. This work presents a comparative evaluation study of CO₂ and steam gasification of a typical post-consumer waste plastics mixture using an Aspen Plus equilibrium model. The effect of flow rate of gasifying medium (CO₂ and/or steam) and gasification temperature on product gas composition, carbon conversion, and cold gas efficiency has been analyzed. Simulation results demonstrate that CO₂ can serve as a potential gasifying agent for waste plastics gasification. The resulting product gas was rich in CO whereas CO₂-steam blends yield a wider H₂/CO ratio, thus extending the applications of the product gas.

Expert panel consensus recommendations for the pharmacological treatment of acute pain in the Middle East region

The findings of an expert panel convened to review critically how best to apply evidence-based guidelines for the treatment of acute pain in the Middle East region are presented. The panel recommended a three-step treatment protocol. Patients with mild-to-moderate levels of acute pain should be treated with paracetamol (step 1). If analgesia is insufficient after 1-2 days, a selective cyclo-oxygenase-2 inhibitor or, if gastrointestinal safety and bleeding risk are not an issue, a non-specific nonsteroidal anti-inflammatory drug, should be used (step 2). If analgesia remains inadequate, treatment with tramadol, or paracetamol plus codeine/tramadol is recommended (step 3). Patients reporting severe pain should be referred to a pain clinic or specialist for opioid analgesic treatment. Measures of pain and functioning that have been validated in Arabic, with culturally appropriate and easy to understand descriptors, should be used. Early and aggressive acute pain management is important to reduce the risk of pain becoming chronic, especially in the presence of neuropathic features.