Comparing Fly Ash Samples from Different Types of Incinerators for Their Potential as Storage Materials for Thermochemical Energy and CO2.

This study aims to investigate the physical and chemical characterization of six fly ash samples obtained from different municipal solid waste incinerators (MSWIs), namely grate furnaces, rotary kiln, and fluidized bed reactor, to determine their potential for CO2 and thermochemical energy storage (TCES). Representative samples were characterized via simultaneous thermal analysis (STA) in different atmospheres, i.e., N2, air, H2O, CO2, and H2O/CO2, to identify fly ash samples that can meet the minimum requirements, i.e., charging, discharging, and cycling stability, for its consideration as TCES and CO2-storage materials and to determine their energy contents. Furthermore, other techniques, such as inductively coupled plasma optical emission spectroscopy, X-ray fluorescence (XRF) spectrometry, X-ray diffraction (XRD), scanning electron microscopy, leachability tests, specific surface area measurement based on the Brunauer-Emmett-Teller method, and particle-size distribution measurement, were performed. XRF analysis showed that calcium oxide is one of the main components in fly ash, which is a potentially suitable component for TCES systems. XRD results revealed information regarding the crystal structure and phases of various elements, including that of Ca. The STA measurements showed that the samples can store thermal heat with energy contents of 50-394 kJ/kg (charging step). For one fly ash sample obtained from a grate furnace, the release of the stored thermal heat under the selected experimental conditions (discharging step) was demonstrated. The cycling stability tests were conducted thrice, and they were successful for the selected sample. One fly ash sample could store CO2 with a storage capacity of 27 kg CO2/ton based on results obtained under the selected experimental conditions in STA. Samples from rotary kiln and fluidized bed were heated up to 1150 °C in an N2 atmosphere, resulting in complete melting of samples in crucibles; however, other samples obtained from grate furnaces formed compacted powders after undergoing the same thermal treatment in STA. Samples from different grate furnaces showed similarities in their chemical and physical characterization. The leachability test according to the standard (EN 12457-4 (2002)) using water in a ratio of 10 L/S and showed that the leachate of heavy metals is below the maximum permissible values for nonhazardous materials (except for Pb), excluding the fly ash sample obtained using fluidized bed technology. The leachate contents of Cd and Mn in the fly ash samples obtained from the rotary kiln were higher than those in other samples. Characterization performed herein helped in determining the suitable fly ash samples that can be considered as potential CO2-storage and TCES materials.

Attitude is everything? The impact of workload, safety climate, and safety tools on medical errors: a study of intensive care units.

BACKGROUND: Hospitals face an increasing pressure toward efficiency and cost reduction while ensuring patient safety. This warrants a closer examination of the trade-off between production and protection posited in the literature for a high-risk hospital setting (intensive care). PURPOSES: On the basis of extant literature and concepts on both safety management and organizational/safety culture, this study investigates to which extent production pressure (i.e., increased staff workload and capacity utilization) and safety culture (consisting of safety climate among staff and safety tools implemented by management) influence the occurrence of medical errors and if/how safety climate and safety tools interact. METHODOLOGY/APPROACH: A prospective, observational, 48-hour cross-sectional study was conducted in 57 intensive care units. The dependent variable is the incidence of errors affecting those 378 patients treated throughout the entire observation period. Capacity utilization and workload were measured by indicators such as unit occupancy, nurse-to-patient/physician-to-patient ratios, levels of care, or NEMS scores. The safety tools considered include Critical Incidence Reporting Systems, audits, training, mission statements, SOPs/checklists, and the use of barcodes. Safety climate was assessed using a psychometrically validated four-dimensional questionnaire.Linear regression was employed to identify the effects of the predictor variables on error rate as well as interaction effects between safety tools and safety climate. FINDINGS: Higher workload has a detrimental effect on safety, whereas safety climate-unlike the examined safety tools-has a virtually equal opposite effect. Correlations between safety tools and safety climate as well as their interaction effects on error rate are mostly nonsignificant. PRACTICE IMPLICATIONS: Increased workload and capacity utilization increase the occurrence of medical error, an effect that can be offset by a positive safety climate but not by formally implemented safety procedures and policies.

Safety climate reduces medication and dislodgement errors in routine intensive care practice.

PURPOSE: To assess the frequency and contributing factors of medication and dislodgement errors attributable to common routine processes in a cohort of intensive care units, with a special focus on the potential impact of safety climate. METHODS: A prospective, observational, 48 h cross sectional study in 57 intensive care units (ICUs) in Austria, Germany, and Switzerland, with self-reporting of medical errors by ICU staff and concurrent assessment of safety climate, workload and level of care. RESULTS: For 795 observed patients, a total of 641 errors affecting 269 patients were reported. This corresponds to a rate of 49.8 errors per 100 patient days related to the administration of medication, loss of artificial airways, and unplanned dislodgement of lines, catheters and drains. In a multilevel model predicting error occurrence at the patient level, odds ratios (OR) per unit increase for the occurrence of at least one medical error were raised for a higher Nine Equivalents of Nursing Manpower Use Score (NEMS) (OR 1.04, 95 % CI 1.02-1.05, p < 0.01) and a higher number of tubes/lines/catheters/drains (OR 1.02, 95 % CI 1.01-1.03, p < 0.01) at the patient level and lowered by a better safety climate at the ICU level (OR per standard deviation 0.67, 95 % CI 0.51-0.89, p < 0.01). CONCLUSIONS: Safety climate apparently contributes to a reduction of medical errors that represent a particularly error-prone aspect of frontline staff performance during typical routine processes in intensive care.