Optimal bed height for passive manual tasks

The aim of this study is to use the dry fibers of date palm as low-cost biosorbent for the removal of Cd(II), and Ni(II) ions from aqueous solution by fluidized bed column. The effects of many operating conditions such as superficial velocity, static bed height, and initial concentration on the removal efficiency of metal ions were investigated. FTIR analyses clarified that hydroxyl, amine and carboxyl groups could be very effective for bio-sorption of these heavy metal ions. SEM images showed that dry fibers of date palm have a high porosity and that metal ions can be trapped and sorbed into pores. The results show that a bed height of 6 cm, velocity of 1.1Umf and initial concentration for each heavy metal ions of 50 mg/L are most feasible and give high removal efficiency. The fluidized bed reactor was modeled using ideal plug flow and this model was solved numerically by utilizing the MATLAB software for fitting the measured breakthrough results. The breakthrough curves for metal ions gave the order of bio-sorption capacity as follow: Cd(II)]Ni(II).

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Column Study for Adsorption of Methylene Blue Dye using Azadirachta indica Adsorbent

Asian Journal of Water Environment and Pollution ◽

10.3233/ajw200050 ◽

2020 ◽

Vol 17 (4) ◽

pp. 47-52

Author(s):

Vibha Goswami ◽

Renu Upadhyaya ◽

Sumanta Kumar Meher

Keyword(s):

Methylene Blue ◽

Flow Rate ◽

Azadirachta Indica ◽

Packed Bed ◽

Blue Dye ◽

Feed Flow Rate ◽

Methylene Blue Dye ◽

Packed Bed Column ◽

Bed Height ◽

Percentage Removal

In this study, synthesised Azadirachta indica adsorbent was used for the removal of methylene blue dye using a packed bed column. The effect of feed flow rate, feed methylene blue dye concentration, and bed height of column on percentage removal of dye was studied. It was observed that the column bed exhausted rapidly at a higher flow rate and therefore, a breakthrough occurred faster. However, it was observed that bed exhaustion time increases on increasing the bed height from 2 to 10 inch at 10 mg/L feed dye concentration and feed flow rate of 40 ml/min. It was also found that the breakthrough curve is more dispersed and the percentage removal of dye increases on decreasing the feed methylene dye concentration from 150 to 10 mg/L. The percentage removal was found to be 96.89% at 20 ml/min of feed flow rate under 10 inch of bed height and 10 mg/L of feed dye concentration. The atomic absorption spectrophotometer and scanning electron microscope were used for estimating the effluent dye concentration from the column and morphological study, respectively.

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Creating a Safer Patient Room Environment: The Contribution of Patient Bed Height

Proceedings of the International Symposium on Human Factors and Ergonomics in Health Care ◽

10.1177/2327857921101163 ◽

2021 ◽

Vol 10 (1) ◽

pp. 180-184

Author(s):

Dorothy Taylor ◽

Janice Morse ◽

Andrew Merryweather

Keyword(s):

Elderly Patient ◽

Fall Risk ◽

The Elderly ◽

Lower Leg ◽

Patient Specific ◽

Leg Length ◽

Patient Room ◽

Patient Falls ◽

Sit To Stand ◽

Bed Height

Elderly patient falls are expensive and may cause serious harm. Studies have identified the sit-to-stand-and-walk (STSW) task as the task where the greatest number of elderly patient falls occur. There is a great need to identify the particular movement and environmental conditions that lead to these elderly patient falls. This study begins to address this gap by evaluating the elderly patient during self-selected hospital bed egress. Using an observed fall risk episode (FRE) as a fall proxy, statistically significant parameters were identified which include bed height, pausing prior to initiating gait, level of fall risk, and Stand phase. Low bed height was identified as the least safe bed height. Patient-specific bed height (PSBH) using the patient’s lower leg length (LLL) is recommended. In addition, suggested guidelines are presented for clinical application in setting PSBH without measuring the patient’s LLL.

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Kinetics and Equilibrium of Radioactive Metal Adsorption onto Sugarcane Bagasse Waste: Comparison of Batch and Column Adsorption Modes

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2019-1418 ◽

2021 ◽

Vol 235 (3) ◽

pp. 281-294

Author(s):

Abida Kausar ◽

Haq Nawaz Bhatti ◽

Munawar Iqbal

Keyword(s):

Sugarcane Bagasse ◽

Flow Rate ◽

Breakthrough Curves ◽

Quadratic Model ◽

Waste Biomass ◽

Initial Concentration ◽

Bed Height ◽

Column Adsorption ◽

Central Composite ◽

Bagasse Waste

Abstract Sugarcane bagasse waste biomass (SBWB) efficacy for the adsorption of Zr(IV) was investigated in batch and column modes. The process variables i.e. pH 1–4 (A), adsorbent dosage 0.0–0.3 g (B), and Zr(IV) ions initial concentration 25–200 mg/L (C) were studied. The experiments were run under central composite design (CCD) and data was analysed by response surface methodology (RSM) methodology. The factor A, B, C, AB interaction and square factor A2, C2 affected the Zr(IV) ions adsorption onto SBWB. The quadratic model fitted well to the adsorption data with high R2 values. The effect of bed height, flow rate and Zr(IV) ions initial concentration was also studied for column mode adsorption and efficiency was evaluated by breakthrough curves as well as Bed Depth Service and Thomas models. Bed height and Zr(IV) ions initial concentration enhanced the adsorption of capacity of Zr(IV) ions, whereas flow rate reduced the column efficiency.

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Modeling of Coal-Biomass Fluidization Using Computational Fluid Dynamics

Volume 7A: Fluids Engineering Systems and Technologies ◽

10.1115/imece2013-63339 ◽

2013 ◽

Cited By ~ 3

Author(s):

Bahareh Estejab ◽

Francine Battaglia

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Hybrid Poplar ◽

Particle Interactions ◽

Particle Mixing ◽

Bed Height ◽

Wood Particles ◽

Computational Fluid Dynamics Cfd ◽

Computational Platform

In an effort to assess the fluidization characteristics of coal-biomass mixtures, computational fluid dynamics (CFD) was used and validated. The gas and solids phases were modeled using an Eulerian-Eulerian approach to efficiently simulate the physics. The computational platform Multiphase Flow with Interphase eXchanges (MFIX) was employed to simulate the particle-particle interactions of coal-biomass mixtures and compare the predictions with experimental data. The coal-biomass mixtures included sub-bituminous coal and hybrid poplar wood. Particles properties of both materials fall within the Geldart A classification. Of particular interest to this study was predicting particle mixing in fluidized beds and biomass hydrodynamics. Both materials and two mass ratio mixtures were studied and pressure drop across the bed for various gas inlet velocities and bed height were analyzed and compared to the experiments.

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