Precise control of drying endpoint and duration in fluidized bed drying via proportional feedback: ensuring granule quality and process robustness.

Hydrogen-based fluidized bed reduction of limonitic laterite nickel ore: towards co-recovery of iron and nickel and metallization enhancement

CFD simulation of heavy oil catalytic cracking in a novel fast fluidized bed

Impact of immersed tube arrangements on heat transfer and solid circulation rate in a U-type loop seal with external heat exchanger in a fluidized bed reactor

From high-to low-risk resistomes: Dynamic shifts in antibiotic resistance during biofilm development in a full-scale biological activated carbon fluidized bed.

Performance of redox Ni–Cu alloy modified calcium-based catalyst for reverse water-gas shift reaction in a fluidized bed reactor

This study presents a novel methodology for applying Electrical Impedance Spectroscopy to analyze the electrical properties of dissolvable powders, when applied as a coating layer to quantify their thickness and moisture content. To address challenges posed by undefined geometries, powders were dissolved and applied as coatings on custom-designed Printed Circuit Board electrodes. Using sodium benzoate as a model material, the drying process was monitored in off-line measurements, revealing distinct transitions in electrical properties. Impedance and phase angle measurements effectively tracked moisture reduction during drying, while coating thickness and solution concentration also influenced conductivity. The findings demonstrate the potential of this approach for industrial applications, such as fluidized bed spray granulation, by enabling real-time monitoring of drying states. • Developed a novel method for coating layer characterization using IS. • Correlated moisture content and coating layer thickness to electrical properties. • Demonstrated potential for monitoring of fluidized bed spray granulation.

Modified silica seed crystals for turbidity reduction and fluoride removal in a fluidized bed crystallization system

Pyrolysis is an important thermochemical conversion process for biomass and is conducted in the absence of oxygen at temperatures between 400 and 1000 ∘C. Biomass pyrolysis yields cleaner combustion fuels by decreasing fuel-bound oxygen and nitrogen species, thus reducing NOX formation and net CO2 emissions. A structural model compound for cyclic peptides — important nitrogen-containing components in biomass — is 2,5-diketopiperazine (DKP). In this work, we apply an automated workflow that combines reactive molecular dynamics simulations with electronic structure calculations at different levels of theory to develop a detailed kinetic model for the pyrolysis of DKP at the level of elementary reaction steps. This complements previous studies that focused only on the net reaction scheme. The developed DKP kinetic submodel for pyrolysis is implemented in the kinetic modeling software OpenSMOKE++ . Under pyrolysis, DKP decomposes into hydrogen cyanide (HCN), carbon monoxide (CO) and hydrogen (H2). Ammonia (NH3) is not formed in primary decomposition steps but rather in secondary reactions involving the primary intermediates. The submodel qualitatively reproduces DKP pyrolysis products observed in a fluidized bed reactor under kinetically controlled conditions and provides a reliable basis for further studies on peptide decomposition. Beyond the specific kinetic submodel, this work proposes a general workflow for investigating thermal decomposition and combustion processes.

Homogeneous crystallization of nickel contaminated industrial wastewater using fluidized bed technology

Pilot-scale biomass pyrolysis dual fluidized bed with in-situ biochar recovery for high-quality bio-oil and negative carbon emissions.

Preparation of orodispersible minitablets containing a poorly compactable drug substance by aqueous fluid bed layering onto coprocessed excipients.

The rapid growth of the global economy and rising energy costs have underscored the need for efficient energy utilization across various sectors. To address this, we developed a novel data-informed digital shadow framework, enhancing energy management within a closed-loop control system, particularly in wastewater treatment facilities. Our approach centers on reducing biogas consumption in the fluidized bed reactor, a crucial component of the incineration process. The digital shadow simulates the entire incineration section by extracting model parameters for key components, including the furnace, dryer, mixer, and heat exchangers, from both physical models and operational data. System-level simulation was performed in AnyLogic software, integrating analytical calculations with data from positioning sensors. The model was informed by operational plant data and validated against historical system data. Evaluation of five operating scenarios demonstrated the capability of the digital shadow to capture system behavior and support operational decision-making. The evaluation of dynamic energy performance identified the most effective scenario, achieving a 40% reduction in biogas consumption while maintaining furnace operation within the temperature range specified by European standards. These findings demonstrate the effectiveness of the digital shadow approach and highlight its potential to deliver substantial annual cost savings in wastewater sludge incineration systems.

ABSTRACT Coal occupies a dominant position in China’s energy structure, with lignite representing a particularly abundant resource. Enhancing the quality and efficient utilization of low-rank lignite is therefore of substantial significance for alleviating energy shortages and promoting sustainable energy development. In this study, a gas – solid area autogenous-medium fluidized bed was employed to upgrade low-rank, high-sulfur lignite through density-based dry separation. The research primarily focused on elucidating the migration and spatial distribution characteristics of coal-powder medium particles with differentiated densities within the area-specific fluidized bed. The dominant density composition of the coal-powder medium and the optimal fluidization area were identified. Furthermore, the effects of operating parameters on the spatial uniformity and stability of bed density, as well as on the distribution patterns of sulfur content, were systematically analyzed, leading to the delineation of functional Areas within the bed. The study also examined the significance levels of various operating factors and their interactions on separation performance, from which the optimal parameter combination was determined. Additionally, the mass distribution of materials across different areas of the bed after separation was investigated. Experimental results indicate that the optimal single-density and mixed-density compositions of coal-powder media for forming a stable area fluidized bed are ρ = 1.45 g/cm3 and ρ = 1.45 g/cm3 +1.65 g/cm3, respectively. Under these conditions, the coal-powder medium particles exhibit uniform and stable distribution throughout the bed, with minimal fluctuations in the mean bed-density profile, yielding an optimal fluidized medium layer in Area I. Three functional spatial Areas within the bed were identified: Area I functions as a low-density separation medium layer enriched in low-sulfur materials; Area II serves as a medium- and high-density stratified area where medium-sulfur materials are interspersed; and Area III acts as a high-density extraction layer uniformly enriched with high-sulfur materials. Among the operational factors, the degree of significance in influencing separation performance follows the order frequency > amplitude > gas velocity. The optimal parameter combination was determined to be A = 3.0 mm, f = 30 Hz, and v = 0.65 m/s. Under these optimal conditions, the upgraded low-rank high-sulfur lignite achieved a clean-coal ash content of 8.67% with a yield of 66.56%, whereas the tailings exhibited an ash content of 43.20% with a yield of 33.44%. The probable error was E = 0.12 g/cm3, demonstrating that the process effectively accomplished clean dry upgrading of low-rank high-sulfur lignite in the 25–0 mm size range.

ABSTRACT Habanero chili is a highly perishable crop, yet a rich source of essential nutrients and bioactive compounds. This study evaluated the effect of three drying technologies – tray drying, fluidized bed drying, and freeze-drying – on the quality of habanero chili powder. Moisture and water activity decreased with drying time, and the modified Page model provided the best fit to the experimental data. Drying technology had a significant influence on color parameters, flow properties, and the retention of key bioactive compounds, including phenolics, carotenoids, ascorbic acid, and capsaicinoids. Overall, freeze-drying and fluidized bed drying achieved higher preservation of nutritional and functional compounds compared to conventional tray drying. These findings demonstrate that the choice of drying technology has a critical impact on the quality and stability of habanero chili powder, providing valuable insights for food processing, innovation, and new product development.

ABSTRACT With the depletion of high-grade mineral resources, increasing attention has been paid to efficient fine particle separation. In this study, a particle-regulated fluidized bed flotation column (PR-FBFC) is proposed, where regulating particles act as dynamic regulators to modify the internal flow field and enhance particle-bubble interactions. The system integrates a fluidized mineralization zone with a column flotation separation zone to enhance particle – bubble collision, attachment, and subsequent separation of mineralized bubbles. The flotation behavior of coal slime was systematically investigated under varying properties of the regulating particles, initial bed heights, and liquid velocities. Results show that the introduction of regulating particles significantly improves flotation performance by stabilizing hydrodynamic conditions and promoting interphase interactions. Among the tested sizes, the 3 mm particle bed exhibits the best performance. Furthermore, increasing liquid velocity and initial bed height markedly enhances the flotation performance. This study provides a promising approach for improving the efficiency of coal slime flotation.

A multi-parameter framework for limestone sorbent selection in fluidized bed combustion (FBC) systems was developed through evaluation of eight Indian limestones (CaCO3: 70–95 wt%) from Western and Southern India. Characterization included chemical composition, mineralogy, mechanical strength, thermal behavior, attrition resistance, thermally induced fracturing (TIF), porosity evolution, sulfation efficiency, and fouling potential during co-firing. Post-calcination porosity (44–58%) and BET surface area (4.69–6.92 m2 g−1) correlated more strongly with sulfation efficiency than CaCO3 content. High-temperature microscopy revealed that TIF-generated hierarchical pore networks enhanced SO2 transport, enabling 30% coarser particle utilization. Sorbent D exhibited superior attrition resistance, retaining 9.6% coarse particles (>500 µm) post-calcination versus 1.4% for E2. Sulfation rankings varied with particle size (coarse: D > B > A > E > C; fine: C > D > E > B > A), demonstrating TIF’s dominance over chemical purity for coarse particles. Co-firing with lignite and petroleum coke produced anhydrite (30–50 wt%) and calcium silicates, indicating fouling risks. The framework enables 15–25% limestone reduction through: (1) chemical screening (CaCO3 >80 wt%, impurities <10–15 wt%), (2) physical characterization (BET >5.5 m2 g−1, TIF evaluation), and (3) performance validation. This approach supports sustainable SO2 emission control in coal-fired power generation, with applicability to India’s 210+ GW thermal power sector. A semi-empirical Sorbent Performance Index (SPI) is proposed, combining CaCO3 content, BET surface area, microstrength retention, TIF score, and impurity penalty, validated against measured limestone requirements addressing a sector facing heterogeneous limestone supply, high-sulfur coals, and tightening emission regulations.

This study compares real-time magnetic resonance imaging (MRI) measurements with three-dimensional CFD-DEM simulations for fluidized beds of Geldart Group D particles under non-vibrated and vibrated conditions. Simulation data were analyzed both in a central 10 mm slice, mimicking the MRI measurement, and across the full three-dimensional domain to assess the representativeness of slice-based evaluation. Bed height, bubble diameter, bubble count, and bubble rise velocity were quantitatively compared. For non-vibrated cases, CFD-DEM agrees well with MRI across all metrics and reproduces established correlations for bubble diameter and rise velocity. For vibrated conditions at 10–30 Hz and 0.5 mm peak-to-peak amplitude (dimensionless acceleration Γ < 1) and superficial gas velocities of 2–4 Umf, no systematic changes in bed expansion or bubble-scale properties was observed. These findings indicate that, for Geldart D particles operating well above minimum fluidization, gas-driven bubbling dominates bed hydrodynamics and low-to-moderate vibration intensities do not substantially alter macroscopic behavior. Comparing slice-based and full-domain analyses revealed systematic offsets in absolute values, most notably in bed height and small-bubble statistics. Thus, central-slice measurements capture hydrodynamic trends reliably but can bias absolute quantities relative to full three-dimensional evaluation. These results define a regime of weak vibration influence for Geldart D particles and provide guidance for interpreting tomographic measurements of fluidized beds. • Comparison of MRI data to CFD-DEM of vibrated and non-vibrated fluidized beds. • CFD-DEM reproduces MRI trends in bubble and bed parameters. • CFD-DEM slightly overpredicts bubble size and bed height, underpredicts bubble count. • No systematic vibration effect observed for vibration acceleration Γ < 1 at 2–4 Umf. • Slice analysis captures trends but differs systematically from full 3D evaluation.

ABSTRACT In the research field of gas-solid separation fluidized bed, aiming at the shortcomings of the existing research on gas-solid separation fluidized bed in particle system and simulation scale, here, a computational particle fluid dynamics (CPFD) method was used to investigate the particle separation and mixing behavior in a pulsating gas-solid separation fluidized bed. The results showed that pulsating gas flow with a frequency of 2–6 Hz can weaken the particle size segregation of a dense medium (particle size range of 100–74 μm), promote particle mixing, and facilitate stable fluidization. At 2 Hz, the density distribution range of 1600–2800 kg/m3 was wider compared with continuous (non-pulsing) flow, but the axial density distribution was more uniform overall. Between 2–8 Hz, gangue passes through the bed faster and in larger quantities compared with the non-pulsating bed. Finally, a kinetic model for particle stratification was established based on a force balance, which elucidates the mechanism by which the inertial force in the pulsating fluidized bed accelerates the particle sedimentation and stratification rates compared with the non-pulsating bed. In doing so, this study provides guidance for the design and industrial scale-up of pulsating fluidized beds.

Enhancing calcium looping for thermochemical energy storage of solar energy in fluidized beds by limestone/SiC mixtures