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Recently, a novel two-stage reactorconfiguration for packed bedchemical-looping combustion (CLC) has been proposed and studied bynumerical simulations. This two-stage CLC consists of two pressurizedpacked bed reactors connected in series, where the first bed containsan oxygen carrier material which is reactive at relatively low temperatures(450 °C) such as CuO/Cu, while the second bed contains an oxygencarrier which is resistant to relatively high temperatures (typically1200 °C) such as NiO/Ni. In this work, this two-stage CLC concepthas been experimentally demonstrated using CuO/Al2O3and NiO/CaAl2O4as bed materials ina high-pressure, high-temperature packed bed reactor. The influenceof the operating conditions has been examined, and a validated reactormodel has been used to scale up the process to industrial scale. Thetwo-stage CLC concept is successfully demonstrated with a maximumtemperature of 839 °C in the second bed. The operating pressure,the throughput during the reduction cycle, and the fuel concentrationshave been found to result in small or negligible influences on themaximum temperature rise. This means that they do not affect the TS-CLCperformance as long as the cycle time is adopted such that the heatproduced in the first reactor bed is exactly transferred to the secondbed. It has also been demonstrated that operation at higher pressures(to reach a higher overall process efficiency) does not affect theperformance of the TS-CLC reactor. However, the fuel type (H2, syngas, CO, or CH4) strongly influences the temperatureincrease in the reactor, since it influences to what extent the oxygencarriers can be reduced. The experimental results could be well describedby a one-dimensional packed bed reactor model provided that the extentof heat losses and the response time of the thermocouples are properlytaken into account. The validated reactor model shows that the desiredgas flow rate at 1200 °C can indeed be produced after some smallchanges in the operating conditions and the active weight contentof the oxygen carriers. Therefore, TS-CLC can be regarded as a feasibletechnology for power production with inherent CO2capturewith high LHV efficiency. [ABSTRACT FROM AUTHOR]

Background: Currently available tools for the management of safety in health care are largely based on quantitative management information. Executive WalkRounds (WalkRounds [WR]) seems useful as a leadership tool to detect "soft signals"-alerts of unsafe situations or practices-and to enhance the mutual trust between frontline staff and the board of directors. The majority of the research on WR has been performed in hospitals. Therefore, a study was conducted to assess how the boards of directors of long term care organizations value WR as a leadership tool to perceive soft signals, and whether soft signals are of added value to enhance patient safety., Methods: WRs were introduced in a convenience sample of six organizations-two mental health care institutions, two nursing homes and home care organizations, and two institutions for the physically and intellectually disabled-between July 2012 and December 2013. Data were gathered from observation and reporting forms. Feasibility was evaluated by open-group interviews. A mixed-method analysis was performed using descriptive statistics and content analysis., Results: WRs were considered feasible, and the added value for the boards of directors consisted of an increased sense of urgency and safety awareness. The dialogue between the board of directors and frontline staff in each organization was essential for a collective patient safety culture. In total, WRs were used 68 times, and 298 soft signals were identified; most addressed care delivery and communication. Overall, 245 improvement activities were reported, of which 109 related to work environment., Conclusion: WRs were considered useful and feasible for detecting soft signals in long term care organizations. These signals are valuable for enhancing patient safety and can be used by the board of directors in addition to the current quality management systems., (Copyright 2016 The Joint Commission.)