Pilot Unit Research Articles

Electropolishing of 316 L Stainless Steel Parts Elaborated By Additive Manufacturing: From Laboratory to Pilot Scale

If the technological progresses of additive manufacturing have enabled to achieve outstanding components with complex geometries, without adversely affecting their core mechanical and structural properties, their degraded surface state remains a critical issue which constitutes a key obstacle for its broad deployment. Indeed, surfaces of parts elaborated by this technic are characterized by a high roughness (Ra up to 40 µm), a strong texture (directly linked to the process and the manufacturing parameters) and to the presence of potentially detachable unmelted particles. Evaluating and developing relevant finishing post-treatments is the aim of the AFTER-ALM project (AFTER-Additive Layer Manufacturing) managed by the IRT M2P (Metz, France) which brings together industrial partners with major OEM such as Airbus, Safran, Liebherr, Collins Aerospace, Stelia, NavalGroup and ArianeGroup. The project also concerns companies specialized in additive manufacturing production (LISI Aerospace, WeAreAerospace, Spartacus 3D, Add-up, Volum-e), surface treatment applicators (Galvanoplast, Chrome Dur Industriel, DEC SA, Satys, GIT), technological partners (Micronics, ABC Swisstech, Beckmann Institute, IREPA laser, R&D Nano, INVENTEC, AQUARESE) and academics ones (UTINAM, CIRIMAT, ENISE).The work presented here focuses on development of an electrofinishing process dedicated to 316 L stainless steel developed by SLM. A study, performed at laboratory scale, allowed to characterize the electrochemical behavior of raw substrates (produced according to different laser scan strategies) was the opportunity to define the bests operating conditions for the levelling (electrolyte composition, temperature, electrical parameters U/I, treatment duration...) with acceptable dissolution rates (around 5 µm/min). The transposition to a pilot unit for the treatment of decametric sizes workpieces (flat or more complex specimens with variable grooves, tubes) requires a precise recalibration. Difficulties are essentially due to the high roughness of the SLM substrates (Ra ⋍30 µm, Rz ⋍ 200 µm), but also to issues related to the process scale-up such as current lines distribution which induces an inhomogeneous dissolution. It is possible to obtain very good results in roughness decrease, but to the detriment of the dimensional characteristics.To meet the dual objective of roughness reduction combined with respect for the geometrical integrity, the use of pulsed potentials has been shown to be highly effective. Tested at laboratory scale and then extended to the pilot scale, a 90% decrease of the roughness was measured while preserving as much as possible the geometries of all samples. These good performances were explained by differences in the mechanisms involved with constant or pulsed potential, as highlighted by transient curves study (figure 1) and spectral power density processing of roughness data. Figure 1

Wet Torrefaction of Poultry Litter in a Pilot Unit: A Numerical Assessment of the Process Parameters

A numerical model for the wet torrefaction of poultry litter in a pilot unit was developed in this study. The model accounted for the following process steps: preheating biomass in a feed hopper, feeding biomass into the reactor, fluidized-bed generation using superheated steam, and the supply of additional heat by the electric heating of the reactor walls. Following a “black box” approach, a major assumption of the model is that the behavior of the fluidized-bed reactor is similar to a completely stirred tank reactor (CSTR). Under this assumption, the properties of the particles and gases do not depend on their location inside the reactor. During wet torrefaction, poultry-litter biomass was heated to a predetermined temperature and decomposed, generating biochar along with a gas phase (torgas), whose amounts depended on the content of inert ash in the biomass particles. Variable optimization in the model was performed using MATLAB software. The model successfully estimated the optimal duration required for the completion of wet torrefaction under various conditions: temperature, batch weight, reactor dimensions, etc. The model was validated using experimental data obtained from a series of wet torrefaction experiments performed in a fluidized bed, and provided reliable estimations of the duration of the process depending on material properties, reactor size and feedstock characteristics.

Evaluation of Tannery Wastewater Treatment by Integrating Vesicular Basalt With Local Plant Species in a Constructed Wetland System

Tannery wastewater is composed of a complex mixture of organic and inorganic components from various processes that can critically pollute the environment, especially water bodies if discharged without treatment. In this study, integrated vesicular basalt rock and local plant species were used to establish a horizontal subsurface flow constructed wetland system and to investigate the treatment efficiency of tannery wastewater. Four pilot units were vegetated with P. purpureum, T. domingensis, C. latifolius, and E. pyramidalis, and a fifth unit was left unvegetated (control). The constructed wetland units in horizontal subsurface flow systems were effective in removing total chromium (Cr), chemical oxygen demand (COD), and 5-day biological oxygen demand (BOD5) from the inflow tannery wastewater. The removal efficiency reached up to 99.38, 84.03, and 80.32% for total Cr, COD, and BOD5, respectively, in 6 days of hydraulic retention time (HRT). The removal efficiency of total suspended solid (TSS), total phosphorus (TP), and nitrate (NO3−) of the constructed wetland units reached a maximum of 70.59, 62.32, and 71.23%, respectively. This integrated system was effective for treating tannery wastewater, which is below the Ethiopian surface water standard discharge limit set to BOD5 (200 mg L−1), COD (500 mg L−1), total Cr (2 mg L−1), NO3− (20 mg L−1), TSS (50 mg L−1), and TP (10 mg L−1).

Concentric Heat Integrated Distillation Column (HIDiC): a new specific packing design, characterization and pre-industrial pilot unit validation

The concept of Heat Integrated Distillation column (HIDiC) was introduced by Mah et al [1] to improve the energy efficiency of distillation processes. Firstly, a brief review of the HIDiC configurations and pilot plants is introduced. The objective of this study is to demonstrate the performance of a new packing specific for HIDiC tested in a concentric HIDiC pilot plant to prove the operability and the overall performance. First, the new specific packing and its characterization are presented. The characterization includes the hydrodynamics, the mass transfer and heat transfer performance. For the experiments on HIDiC pilot plant, several tests are performed at steady state of 90 min. One of these experiments is presented with the operating parameters (boiler heat and pressure ratio). The cyclohexane/n-heptane binary mixture is used for these experiments. The simulation results of a classical distillation column are compared to HIDiC column steady state operation. This comparison demonstrates energy savings about 40 %.

Use of charcoal from gasification residues in adsorption pilot plant for the practical application of circular economy in industrial wastewater treatment

In the present work, the charcoal obtained after the gasification of wood residues was tested in a pilot adsorption unit to evaluate the feasibility of treating real textile wastewater on a semi-industrial scale. The aims were to evaluate the global performance of the adsorption column in the pilot system using a methylene blue (MB) solution, and then a real sample of textile wastewater. Two charcoal samples, which were a by-product of the gasification process, were obtained, characterized, and tested with a MB dye solution. The experimental adsorption capacity of the fixed-bed was near 34 mg.g−1 in both cases, and the overall removal efficiency of the column was >91%. Experimental data were fitted according to the Thomas and Adams-Bohart models. The pilot plant proved to be effective for improving the treatment of real textile wastewater, regarding the removal of color and part of organic matter, verified by the evolution of chemical oxygen demand over time. The cost to operate the pilot plant was calculated, and the contribution to the circular economy was considered. The pilot unit was promising for improving the wastewater treatment process, adding value, and giving a new purpose to a waste that normally would be disposed in the environment.

Hydrodynamic study of the oil flow in a protective relay coupled to a power transformer: CFD simulation and experimental validation

The present study aimed at performing a hydrodynamic analysis of the safety device's behavior in a gas relay, using computational fluid dynamics techniques and experimental data validation obtained in a protective relay pilot unit (PRP) using different safety flaps geometries for fault detection within high-power transformers. The proposed methodology was carried out in four stages: (i) development of computational meshes from the three-dimensional geometry of the protective relay and safety flaps; (ii) specification of the physical properties of fluids, boundary conditions, and fluid dynamic models; (iii) obtaining speed profiles, flap angle, oil flow and system pressure difference; and (iv) comparison of simulated and experimental data. The devices installed in the relay showed satisfactory performance for failures caused by the oil volumetric expansion. It was observed that from the flap 10° tilt, the orifice ceases to be the preferred path oil, reducing detection sensitivity of the flow. Using the CFD (computational fluid dynamics) computational tool, it was possible to understand the flow behavior within the relay, allowing to detect quickly and efficiently cases of failure with oil expansion.

Treatment of gaseous emissions from tire manufacturing industry using lab-scale biofiltration pilot units

Continuously seeking the improvement of environmental protection, the limitation of exhaust emissions is of significance for the tire manufacturing industry. The aim of this study is to assess the potential of biofiltration for the treatment of such gaseous emissions. This work highlights that biofiltration is able to remove both hydrophilic and hydrophobic compounds within a single pilot unit of biofiltration. Due to Ethanol/Alkanes ratios (95/5 and 80/20), high performance levels were observed for low EBRT (16 and 12 s). After twenty days of stable running, the dynamic of stratification patterns could be explained as a result of species coexistence mechanisms. While its impact on performance has not been observed under stable operating conditions, the use of an adsorbent support such as granular activated carbon (GAC) could be relevant to promote system stability in the face of further perturbations, such as transient regimes, that are problematic in full-scale industrial applications.

Fine hydraulic screening of ground ores on a multi-frequency screen by Kroosh Technologies: in-process testing

This paper describes high-frequency screens developed by Derrick and Landsky and multi-frequency screens developed by Kroosh Technologies, how they function and the differences between them. The fundamental difference between the vibration parameters in the high-frequency and multi-frequency modes is the difference in the accelerations created by the vibration excitation system. In high-frequency screens, the maximum acceleration of the screening media does not exceed 10g. In multifrequency screens, the measured positive and negative accelerations of the screen body are 3g. However, when interacting with the developed system of multi-frequency vibration, the positive peak accelerations of the screen mesh reach (50÷60)g, and the negative accelerations — (150÷200)g. This mode ensures that the screening media are kept free from material, and thus the specific throughput and the screening efficiency rise. A few dozens of tests with different ores were carried out on a pilot unit. The paper describes some qualitative and quantitative results of hydraulic screening of finely ground ores with 75 and 100 micron media, which were obtained on a pilot unit with a 1,500×600 mm multi-frequency screen. As a result of hydraulic screening of ground chrome ore with a 0.1×2.6 mm mesh at the ore feed rate of 2.65 t/(h·m2), the undersize product included 91.8% of particles smaller than 100 microns. With the hydraulic screening of ground chrome ore with a 0.075×2.6 mm mesh at the ore feed rate of 1.66 t/(h·m2), the recovery of particles smaller than 75 microns as the undersize product was 88.78%. With the hydraulic screening of ground tin ore with a 0.1×2.6 mm mesh at the ore feed rate of 2.94 t/(h·m2), the recovery of particles smaller than 100 microns as the undersize product was 93.93%. Multi-frequency screens are successfully used by the concentrator plants of Kazzinc and Glencore (South Africa).

Insights in the phenomena involved in deactivation of industrial hydrocracking catalysts through an accelerated deactivation protocol

A representative accelerated experimental deactivation procedure was developed to understand the activity loss of bifunctional vacuum gasoil (VGO) hydrocracking catalysts over time. Experiments were performed in an up-flow fixed-bed pilot unit with a typical vacuum gas oil feedstock. The deactivation was measured by tracking the decrease of VGO conversion (370 °C+) with time on stream. The catalyst consisted of nickel-molybdenum sulfide particles dispersed on a carrier containing USY zeolite. The impact of temperature, liquid hourly space velocity (LHSV), hydrogen to hydrocarbon (H2/HC) ratio and organic nitrogen (Norg) on the catalyst deactivation rate was first studied. The variables with the most significant impact on conversion loss were temperature and space velocity. Temperature directly influences the production rate of coke precursors, whereas space velocity affects the local concentration of feed contaminants along the reactor. Based on these results, the following operating conditions were selected to establish the final accelerated deactivation experimental protocol: T = 418 °C, LHSV = 3 h−1, H2/HC = 1500NL/L, P = 14 MPa, organic nitrogen content (Norg) = 150 ppm weight, total nitrogen content = 2500 ppm weight and a total time on stream of 30 days. Spent samples from this procedure presented similar properties to some industrial catalysts submitted to cycle lengths between 12 and 18 months. Both types of samples yield similar values of surface area and pore volume loss as well as a similar amount and nature of coke deposits. These results led to the qualitative validation of the protocol representativeness. This experimental procedure was then used to get more insight into the deactivation phenomenon. It was found that the organic nitrogen content of the feedstock is crucial, as it determines the ratio between available metal and acid sites. This ratio determines the reactions that take place and, therefore, the type of coke produced.

Nursing Praxis for Reducing Documentation Burden Within Nursing Admission Assessments.

The purpose of this quality improvement project was to conduct a scholarly assessment of the information collected within the nursing admission encounter and implement content revisions across three pilot medical surgical units. The guiding principles were to preserve regulatory information, identify nurse-sensitive data, and eliminate nonessential information. The goal was to decrease the number of clicks and time expended to document electronically an acute admission encounter by 20% and to project the number of hours returned to patient care as a result of decreasing computer clicks. A second goal was to quantify the projected costs of completing a nursing admission encounter. This quality improvement project leveraged nurse executive competencies to intersect the nursing process to develop a nursing documentation praxis. This author's praxis reduced nursing documentation burden in clicks by 29% and reduced time to document on an admission encounter by 34%. This restored the focus on nurse-patient interactions by returning 1016 hours per year to patient care activities, across three pilot units, as well as quantified the costs of completing a nursing admission assessment to utilize in future cost analysis of nursing tasks.

Plate heat exchanger design for the utilisation of waste heat from exhaust gases of drying process

The vapour condensation is typical for processes of waste heat recovery from exhaust gases. It complicates the selection of condensers and requires reliable correlations for estimation of heat transfer coefficients and pressure drop in the unit. In the presented paper, a novel model was elaborated to be applied for commercially produced plate heat exchangers (PHEs) assembled from plates with different geometries of corrugations, which accounts the change of process parameters at the main corrugated field, in PHE collectors and channels distribution zones. The process of waste heat recovery from exhaust gases after tobacco drying is discussed in the case study. The pilot unit assembled with PHE of TS-6MFG type manufactured by Alfa Laval was installed at a tobacco factory. The examined condensing media was an incoming air-steam mixture with 10% of air content and temperature equal to 140 °C. The comparison of modelling results and data of industrial operation has shown good accuracy of prediction. It allowed recommending obtained correlations and developed mathematical model for the design of plate heat exchangers in applications with heat utilisation from exhaust gases after drying processes in the industry, with a considerable saving of heat energy. In the considered example, it is up to 640 kW or 2090 kJ/kg of exhaust gases.

Flue gas purification from SO2 and NOx using molten mixture of alkali metal carbonates

ABSTRACT Sulfur dioxide (SO2) and nitrogen oxides (NOx) in flue gas are a hazardous atmospheric pollutant associated with coal combustion and non-ferrous metal production. Here we report that laboratory pilot unit for scrubbing of industrial flue gas containing 80 ± 2 ppm SO2 followed by melt regeneration with either CO or natural gas, verified that only 1.5–2.0 ppm SO2 remained in the flue gas. The tests with the semi-industrial scale unit (271.26 kg of the eutectic carbonate melt and flue gas containing 0.15% SO2, 13 ppm NO, 52 ppm NO2) were received. In all tests, sulfur extraction from flue gas to the carbonate melt was >90–95% and nitrogen oxides extraction from flue gas to the carbonate melt was 60%. Sulfur and nitrogen oxides extraction from carbonate–sulfate–nitrite melt during regeneration stage was >99%. Carbonate melt-based SO2 scrubbing therefore represents a practical and economical method for limiting sulfur and NOx emission to the atmosphere from both coal-firing power stations and non-ferrous metallurgical processing plants.

Improving the performance of vertical flow constructed wetlands by modifying the filtering media structure.

The aim of this research was to study the influence of the bed media configuration and particle size on the treatment efficiency of subsurface vertical flow (VF) constructed wetlands (CWs) treating municipal wastewater. Two outdoor pilot units (VF1 and VF2, planted with Phragmites australis) with the configuration C1 were operated in parallel for 2 years at similar surface loading rates of 9.7 ± 3.2 (VF1) and 10.1 ± 3.3 (VF2) g biological oxygen demand (BOD5)/m2·day (19.5 ± 6.4 (VF1) and 20.4 ± 6.2 (VF2) g chemical oxygen demand (COD)/m2·day). A different configuration C2 was used during the third year at 16.9 ± 4.6 (VF1) and 18.2 ± 3.0 (VF2) g BOD5/m2·day and 26.0 ± 7.2 (VF1) and 28.0 ± 4.7 (VF2) g COD/m2·day. Two different filtering materials (1-3-mm sand for VF1 and 2-6-mm fine gravel for VF2) were used for configuration C1. The same units were modified after 2 years of operation by adding a 10-cm layer of fine sand (0-2 mm) on the top (configuration C2). In C1 conditions, the unit with the coarse material VF2 showed significantly (p < 0.05) lower removal efficiencies of total suspended solids (TSS) and BOD5 than VF1, and both units failed to meet the BOD5 discharge limit. In C2 conditions, removal efficiencies reached 82% TSS, 97% BOD5, 76-81% ammonia, and 60-66% TN, without significant differences between VF1 and VF2 units. Removal efficiencies were significantly higher for configuration C2 than that for C1, due to the positive effect of the upper fine sand layer. The presence of this fine sand layer doubled the water retention time and increased the removal rates, while the infiltration rates were high enough for an operation free of clogging.

Hydraulic characterization and removal of metals and nutrients in an aerated horizontal subsurface flow “racetrack” wetland treating primary-treated oil industry effluent

Constructed wetlands (CW) are an attractive technology due to their operational simplicity and low life-cycle cost. It has been applied for refinery effluent treatment but mostly single-stage designs (e.g., vertical or horizontal flow) have been tested. However, to achieve a good treatment efficiency for industrial effluents, different treatment conditions (both aerobic and anaerobic) are needed. This means that hybrid CW systems are typically required with a respectively increased area demand. In addition, a strong aerobic environment that facilitates the formation of iron, manganese, zinc and aluminum precipitates cannot be established with passive wetland systems, while the role of these oxyhydroxide compounds in the further co-precipitation and removal of heavy metals such as copper, nickel, lead, and chromium that can simplify the overall treatment of industrial wastewaters is poorly understood in CW. Therefore, this study tests for the first time an innovative CW design that combines an artificially aerated section with a non-aerated section in a single unit applied for oil refinery wastewater treatment. Four pilot units were tested with different design (i.e., planted/unplanted, aerated/non-aerated) and operational (two different hydraulic loading rates) characteristics to estimate the role of plants and artificial aeration and to identify the optimum design configuration. The pilot units received a primary refinery effluent, i.e., after passing through a dissolved air flotation unit. The first-order removal of heavy metals under aerobic conditions is evaluated, along with the removal of phenols and nutrients. High removal rates for Fe (96–98%), Mn (38–81%), Al (49–73%), and Zn (99–100%) generally as oxyhydroxide precipitates were found, while removal of Cu (61–80%), Ni (70–85%), Pb (96–99%) and Cr (60–92%) under aerobic conditions was also observed, likely through co-precipitation. Complete phenols and ammonia nitrogen removal was also found. The first-order rate coefficient (k) calculated from the collected data demonstrates that the tested CW represents an advanced wetland design reaching higher removal rates at a smaller area demand than the common CW systems.

Performance Improvement of Solar Water Distillation System Using Nano-Fluid Particles

The aim of this work is to utilize nano-fluid particles (Titanium dioxide, TiO2) to enhance the heat transfer characteristics of the Heat Transfer Fluid (HTF) of the solar heating system to improve its thermal performance. It is found that using the nano-fluid particles like TiO2 improves the heat transfer characteristics of the HTF of the solar water distillation system and consequently increases the rate of daily water productivity. It is found also that the system can produce distilled water of 5.616 m3/day, 6.048 m3/day, 6.134 m3/day, and 7.128 m3/day in case of using TiO2 with a concentration of 0 mg/l, 75 mg/l, 80 mg/l, and 100 mg/l respectively. The experimental pilot unit was installed in Solar Energy Department, National Research Centre, and Giza, Egypt. Several test runs are performed to measure all assigned parameters that affect the system performance. The tested system can positively contribute in water desalination units, especially in rural and isolated communities.

Hourly Rounding and Fall Prevention among the elderly in long term care: A change process.

AbstractLong term care facilities have a rising rate of falls and fall related injuries with increasing cost and more hospitalization. Hourly rounding® is an evidenced based intervention that is proactive for nursing staff to be able to identify patient’s needs. This helps with positive fall prevention outcome. This project focused on process improvement efforts for 10 weeks and examining the education and implementation of an evidenced-based hourly rounding program that assisted in reducing the number of falls in the pilot unit. The implementation of the intervention took place in a long-term care facility located in Dallas, Georgia. The hourly rounding tools used in this project were the Studer Group hourly rounding log and competency checklist with permission. Twenty staff members were included in the sample, age 18 years and 60 years. The unit has 41 residents who were included in the pilot case study design. Staff members were first educated regarding hourly rounding and documentation on the hourly rounding log was done two days before implementation and the pre and post fall rate was retrieved from the facilities fall database. Competency checklist was completed prior to implementation and post implementation to evaluate staff understanding of the main tenets of the 4 P’s (potty, pain, possession, and position). For this project, descriptive statistics was used to help determine fall rates. Minitab was used to analyzed data and to determine if it was clinically significant. In the ten weeks following the hourly rounding implementation, participants performed hourly rounding by incorporating it to each resident’s daily routine and documented their rounds on the log sheet. The results indicated that it is statistically significant and with a P-values = -&lt;0.0001 and t-value = -5.81.Keywords: Rounding and education; fall risk; fall reduction; older adult patients; quality improvement; fall prevention; fall and fall related injury.

Productive and reproductive traits of Kholmogorskaya breed of cattle when feeding grain molasses

The purpose of the work was to increase the effectiveness of rearing of young animals and milk production by providing dairy cows with easily digestible sugars obtained from local grain raw materials. The research on the use of grain molasses produced from rye grain in a pilot unit in the Sharkansky RTP UZHK-1000 in feeding cattle of Kholmogorskaya breed under the environments of the Udmurt Republic has been carried out. The innovative small-sized treacle unit operating on the basis of the principle of cavitation technology is designed for the enzymatic cleavage of grain polysaccharides to a more accessible form of sugars for assimilation. It has been revealed that the feeding of grain molasses to young cattle in the amount of 3 kg/head/day had a positive effect on the increase in the average daily gain of live weight and the intensity of growth of animals. In the first-calf heifers in control group the age of achieving the first insemination was 14,7 months with the live weight of 374,6 kg, in the first-calf heifers in experimental group it was 13,8 months, while their live weight was 378,2 kg. The insemination index in the first-calfheifers of the control group was satisfactory and amounted to 2,0, and in the cows of the experimental group it was good – 1,6 (P ≥ 0,95). The maximum milk productivity of first-calf heifers for 305 days of lactation has been recorded in the cows of the experimental group, where grain molasses was used, and amounted to 7702,0 kg, which was more than in the control group by 157 kg or 2,1% (P ≥ 0,95). Milk from cows of the experimental group was the most suitable for the production of fermented milk products. The physical and chemical parameters of milk were also higher in the group in which grain molasses has been fed. The lowest consumption of milk for the production of 1 kg of cottage cheese was noted in the experimental group of cows 6,43 kg, the same trend has been observed in the production of cheese where the consumption was 8,7 kg.

Using the unit software model to improve design solutions and optimize process management

Advanced design power units are distinguished by a high degree of digital transformation. Therefore, of particular interest are operator information (intelligent) support systems, which can reduce the workload on operating personnel as well as predict possible deviations long before they evolve into severe emergencies. The article analyzes the current standard process documentation that requires solutions to support the operator and determines the list of system functions that should be provided to improve the safety level of nuclear power plants. A brief overview of the world experience in implementing such solutions is also provided. As an example of the further development of operator support systems, the authors consider the operator information support system (OISS), which is being developed at the NvNPP pilot unit with the VVER-1200 reactor. The OISS functions will make it possible to fulfill the requirements of standard process documentation that are currently not implemented in the power unit design. The key features of the OISS under development are step-by-step interactive procedures and the unit software model. The authors provide a brief description of the power unit software model and consider several examples of its practical application as part of the OISS to improve design solutions and optimize automatic process control. In the years ahead, it is proposed to implement the OISS at power units under construction in order to reduce the information overload of operators and create conditions for a step-by-step increase in the automation level of the power unit control.

Performance Evaluation of Dual Purposes Solar Heating System Using Heat Pipe Evacuated Tube Solar Collector

The aim of this work is to develop dual purposes solar heating system using a heat pipe evacuated tube solar collector. The heat transfer fluid between the thermal loads and the solar collector loop was heating oil. The study provided two thermal loads; a solar water heating system and a solar baking/cooking system that had experimentally investigated under various weather conditions. The experimental pilot unit was installed in the Solar Energy Department, National Research Centre, Giza, Egypt. Several test runs were performed to measure all assigned parameters that affect the system performance. The system is designed to provide hot oil surrounding the inner vessel of the baker with a temperature up to 250o C while the raw food can be baked/cooked and the outlet thermal energy can be used for heating water via an immersed coil in the hot water storage tank; then the relatively cooled oil is returned to the solar collector via hot oil circulating pump. The tested system can be positively contributed to baking and cooking purposes and providing hot water as well. It is considered an environmentally friendly system and can significantly enhance sustainable communities. The system is capable to produce hot water temperature up to 85 oC and an average temperature of about 60 oC during the day which is suitable for residential purposes and industrial process as well The auxiliary heating system can be an electric source in case of using in urban areas and can be renewable energy source like biogas or hydrogen fuels in rural and isolated areas.

Admission criteria for a cardiovascular short stay unit: a retrospective analysis on a pilot unit

Rapid intensive observation (RIO) units have been created to guarantee high standards of care in a sustainable health-care system. Within short stay units (SSUs), which are a subgroup of RIOs, only rapidly manageable patients should be admitted. Physicians are unable to predict the length of stay (LOS) as objective criteria to make such a prediction are missing. A retrospective observational study was carried out to identify the objective criteria for admission within a cardiovascular care-oriented SSU. Over a period of 317 days, 340 patients (age 69.4 ± 14.7 years) were admitted to a pilot SSU within our internal medicine department. The most frequent diagnoses were chest pain (45.9%), syncope (12.9%), and supraventricular arrhythmias (11.2%). The median LOS was 4 days (quartile 1:3; quartile 3:7). Predictors of LOS ≤ 96 h were age < 80, hemoglobin > 115 g/L, estimated glomerular filtration rate > 45 mL/min/1.73 m2, Charlson Comorbidity Index < 3, Barthel Index > 40, diagnosis of chest pain, syncope, supraventricular arrhythmias, or acute heart failure. The HEART (history, ECG, age, risk factors, troponin) score was found to be excellent in risk stratification of patients admitted for chest pain. Blood tests and anamnestic variables can be used to predict the LOS and thus SSU admission. The HEART score may help in the classification of patients with chest pain admitted to an SSU.