Flux Components Research Articles

Characterization of Volcano-Sedimentary Rocks and Related Scraps for Design of Sustainable Materials.

This work started as a joint academia and company research project with the aim of finding new applications for domestically sourced volcanic products and related waste (pumice, lapillus, zeolitic tuff and volcanic debris from Tessennano and Arlena quarry) by creating a database of secondary volcanic raw materials and their intrinsic characteristics to help industry replace virgin materials and enhance circularity. In this context, accurate chemical, mineralogical, morphological, granulometric and thermal characterizations were performed. Based on the results presented, it can be concluded that due to their lightness, these materials can be used in the design and preparation of lightweight aggregates for agronomic purposes or in the construction field. Furthermore, due to their aluminosilicate nature and amorphous fraction, pumice and lapillus can play the role of precursor or activator for geopolymer preparation. With its porous nature, zeolitic tuff can be exploited for flue gas treatment. Due to the presence of feldspathic phase (sanidine), these materials can be used in tile production as a fluxing component, and with their pozzolanic activity and calcium content, they have application in the binder field as supplementary cementitious material or as aggregates.

Direct numerical simulation of flow and heat transport in a closely-spaced bare rod bundle

Direct Numerical Simulation (DNS) of fully-developed flow and heat transfer is performed for a bare rod bundle with a low pitch-to-diameter ratio using the highly-scalabale spectral element code Nek5000. The simulation is performed at a Reynolds number, Reh, based on the bulk velocity and hydraulic diameter, of 9800, with iso-temperature and iso-flux thermal boundary conditions and Prandtl numbers 0.025, 1.0 and 2.0. The mean velocity and temperature statistics are first validated against the experimental measurements of Hooper et al. (1983) and complementary DNS results of Lai et al. (2019) which are reported in the literature at a higher Reh of 22,600. The mean flow and temperature are demonstrated a similar behaviour at the present low Renolds number and the higher Reynolds number of Lai et al. (2019), indicating the Reynolds number scaling of the mean flow. The anisotropy of the flow is illustrated using distribution of normal and Reynolds stresses, and the Lumley invariant map. It is shown that the turbulence in the subchannel region is characteristic of wall-bounded turbulent flows such as channel flows. In the narrow gap, however, turbulence is suppressed, only enhanced in the streamwise direction due to flow pulsations. Further, temperature statistics with both thermal boundary conditions are presented, demonstrating the effect of the Prandtl number on the mean and fluctuating quantities. The temperature statistics with iso-temperature wall boundary conditions, not reported in literature before, are shown to behave differently in the interstitial subchannel region and the narrow gap between two rods. The distribution of turbulent heat flux is also presented. The streamwise component of turbulent heat flux is again shown to be enhanced, in comparison to the same in the subchannel. The pulsating motion of flow across the narrow gap is discussed further. A frequency analysis of the velocity in the narrow gap elucidates the frequency of flow pulsations. Unlike mean flow statistics, the flow pulsations are shown to exhibit a low Reynolds number effect. The reference DNS data presented in the present work, complementary to that of Lai et al. (2019), serves as a benchmark against which lower order turbulence models may be further developed or improved. In particular, the newly presented anisotropy data and the turbulence heat flux data are essential for further development, improvement and validation of turbulent heat transfer models at different Prandtl numbers.

Final Design of Vacuum Pumping Systems for the Material Plasma Exposure eXperiment

The Material Plasma Exposure eXperiment (MPEX) vacuum pumping system is responsible for creating prototypic conditions in the plasma material interaction chamber that mimic those in a fusion reactor divertor region. Additionally, the vacuum system needs to minimize the pressure in the plasma heating region to improve the coupling of the electron cyclotron heating and ion cyclotron heating to the plasma, minimizing waste heat exhausted to high heat flux components. The final design of the system has been sized to comply with the vacuum pump operating environment and to reduce the number of unique pumps required while meeting performance requirements. Bounding cases with and without the plasma present have been developed in the pumping analysis, and an initial calculation has been performed based on the plasma pumping identified in Proto-MPEX operation though this result will remain unverified until MPEX operation.

Characteristics, seasonal variations, and dry deposition fluxes of carbonaceous and water-soluble organic components in atmospheric aerosols over China's marginal seas

A total of 37 atmospheric aerosol samples were collected over the Yellow and Bohai Seas (YBS) during four cruises in autumn, winter, spring and summer from 2017 to 2018. The concentrations of organic carbon (OC) and water-soluble organic carbon (WSOC) ranged from 1.04 to 15.43 μg m−3 and 0.77–5.49 μg m−3, respectively, with higher values in autumn and winter than in spring and summer. WSOC contributed 68.49 % to OC in summer and 34.55 % in winter and was affected by temperature and relative humidity. Dicarboxylic acid showed a predominance of oxalic acid followed by malonic and then succinic acids. The contributions of secondary sources to OC and WSOC were 54 % and 65.3 %, respectively, indicating the importance of secondary aging in improving the water solubility of OC. The dry deposition flux of WSOC over the YBS was estimated to be 0.87 mg m−2 d−1, which might play a potential role in the marine carbon cycle.

Using sensorless direct torque with fuzzy proportional-integral controller to control three phase induction motor

Induction motors (IM) attracted many researchers in the last few decades. In this field, various applications are implemented, such as servo motor drives and electric vehicles. This work applies a sensorless direct torque controller (DTC) to control a three-phase IM. System dynamics of the IM were derived. A nonlinear dynamic model had introduced with white noise. Given the complexity of the dynamics, the Jacobean Linearization technique has been used to obtain the linear model for a control task. A DTC technique is employed to control the motor speed of the system with a combination of two controllers. The fuzzy proportional-integral (PI) controllers are applied to obtain the reference torque based on an optimization process against the speed error raise. The optimizer is called grey wolf optimizer (GWO) and is implemented to achieve the centre values of the two output memberships for the fuzzy PI controllers. Then the extended Kalman filter (EKF) is used to evaluate the direct and quadratic components of the rotor flux and rotor speed from the observation of stator voltages and currents. The system is tested employing MATLAB simulation software and determines the targeted results. The outcomes are evaluated to improve the control performance.

Effect of ion-induced nuclear reactions on structure modification and radiolysis in LiF irradiated by 410 MeV 36S ions

The objective of this research is to study the structural damage in LiF crystals irradiated with 410 MeV 36S ions. We report on the appearance of a remarkable structural damage far (hundreds of μm) beyond the penetration depth (136 μm) of sulfur ions. Selective chemical etching on samples irradiated at room temperature revealed the formation of extended defects within the ion-irradiated zone and also beyond the range of sulfur ions. Based on AFM image analysis, the defects were identified as nano-size colloids (10 nm). In the irradiated zone, nanoindentation tests indicated a significant hardening effect. Annealing experiments showed manifestations of intense radiolysis both in the ion-irradiated and beyond the range areas with a maximum of around 620 K. Comparison of experimental results with those of performed model simulation using Monte-Carlo particle transport code FLUKA support the assumption that the cause of the observed long-range damage is irradiation by secondary particles created in inelastic nuclear collisions between incident sulfur ions and lithium and fluorine nuclei of the target atoms. Neutrons, γ-rays and protons are rated as the dominating components of the secondary particle flux. The results can be helpful for assessing the risks for damage delocalization and for reasonable selection of ions in the applications of ion technologies to optical materials like LiF.

Numerical Investigation on Enhanced Heat Transfer with Tilted Hypervapotron Structure of the Fusion Blanket

High flux components in fusion reactor are designed to transfer high thermal loads from the core plasma under steady-state operation and emergency conditions. In order to improve the heat transfer ability, hypervapotron structure is proposed to promote the heat transfer performance by optimizing the thermal hydraulic design. In this paper, three-dimensional numerical simulation was carried out using CFD methods for the improved solution of the first wall. The results show that the heat transfer performance of the triangular fin structure with tilt angle of 30° is superior to 0 °, 15°and 45°. At a typical flow rate of 2 m/s, the heat transfer efficiency of the triangular fin with tilt angle of 30° improved by a maximum of 118.1% compared with that of the smooth flow channel. In addition, the heat transfer performance of the triangular fin structure is better than other fin structure, and its maximum temperature drops by 136.3K compared to the smooth flow channel. The design solution may provide a viable new method for efficient cooling of future fusion reactor components with high heat flux.

Assessment of Top of Atmosphere, Atmospheric and Surface Energy Budgets in CMIP6 Models on Regional Scales

AbstractWe examine top of atmosphere (TOA), atmospheric, and surface energy budget components of 53 CMIP6 models for the period 2000–2009 on regional scales with respect to two reference data sets: the NASA Energy and Water cycle Study (NEWS), from which we adopt the regional decomposition, and the Clouds and the Earth's Radiant Energy System (CERES) Energy Balanced and Filled (EBAF). Focusing on regional scale, CMIP6 models tend to have more energy entering or less energy leaving the climate systems at TOA over the Northern Hemisphere land, Southern Hemisphere ocean and the polar regions compared to CERES EBAF, while the contrary applies in other regions. Atmospheric net shortwave and longwave fluxes both tend to be underestimated in CMIP6 models as compared to EBAF, with substantial regional differences. Regional surface radiative fluxes as reported by NEWS and EBAF can differ substantially. Nevertheless, robust regional biases exist in CMIP6. Surface upward shortwave radiation is overestimated by 43 (81%) models over Eurasia. For almost all surface radiative flux components over the North Atlantic and Indian Ocean, there are at least 21 (40%) models which fall outside the NEWS uncertainty range. Latent heat flux is overestimated over most of the land and ocean regions while firm conclusions for sensible heat flux remain elusive due to discrepancies between different reference data sets. Compared to CMIP5, there is an overall improvement in CMIP6 on regional scale. Still, substantial deficiencies and spreads on regional scale remain, which are potentially translated into an inadequate simulation of atmospheric dynamics or hydrological cycle.

Model Predictive Torque Control for Permanent- Magnet Synchronous Motors Using a Stator- Fixed Harmonic Flux Reference Generator in the Entire Modulation Range

To increase torque and power conversion of permanent-magnet synchronous motors (PMSMs) at high-speed operation, the dc-link voltage of the inverter must be fully utilized during steady-state and transient operations. This article proposes the incorporation of a harmonic reference generator (HRG) with a pulse clipping (PC) scheme into a model predictive control framework to achieve highest power output. The HRG calculates flux references in the stator-fixed coordinate system for an underlying continuous-control-set model-predictive flux control (CCS-MPFC). These reference trajectories contain the harmonic flux component induced by the voltage hexagon in the overmodulation range and specific switching states (e.g., six-step operation) of the inverter are ensured by the proposed PC scheme. This enables a seamless transition to the overmodulation range including six-step operation and increases the drive's power conversion to its maximum extent. Since the flux differential equation in the stator-fixed coordinate system, used as motor model for the HRG and CCS-MPFC, is able to represent PMSMs with linear and nonlinear magnetization, the proposed approach is well suited for the control of PMSMs with nonlinear magnetization. Extensive transient and steady-state experimental investigations on a highly utilized PMSM in the entire modulation and speed range prove the performance of the proposed approach.

트랙션용 다자유도 구형 전동기의 구동을 위한 간접 벡터 제어 연구

The multi-degree-of-freedom spherical motor for traction has characteristics of rotation and steering. Although it is base on the rotation principle of an induction motor, only a spherical motor control method is required for rotation and steering. In order to estimate the speed command of the rotor, the mechanical angular velocity of the rotor is measured using an optical sensor, and the slip angular velocity is calculated with the current command of the d-q axis stator of the synchronous coordinate system. The rotor magnetic flux angle can be obtained in the above two ways, and through this, the vector control of the spherical motor is achieved. The desired magnetic flux component current and torque component current are distributed to operate the spherical motor. As such, the indirect vector control method has advantages in that it is simple to implement because it does not use the magnetic flux linkage of the rotor and that it is easy to operate from low speed to rated speed.

Non-intrusive reduced-order modeling of radiation transport in the atmosphere

In this work, we investigate a non-intrusive parametric reduced-order model (ROM) for atmospheric scale neutral particle transport via an application to neutron transport. The spatial domain of interest consists of an 80-km tall cylinder with a 20-km radius. The system parameters are the elevation and emission spectrum of the radiation source, as well as the relative humidity, which alters the cross sections of the atmospheric air. The full-order model (FOM) employs a first-collision source approach to mitigate ray effects. The separate computation of the uncollided and collided flux components is exploited in the reduced-order model (ROM). The ROM utilizes various non-linear transformations of the FOM solution to address the many orders of magnitude present in the FOM data, which can vary by up to 26 orders of magnitude. Subspace discovery is performed on this transformed dataset and the parametric dependence in this latent space is learned via Gaussian process regression. Speed-up factors of 5,100× to 9,700× are observed, while maintaining less than 10% pointwise error throughout most of the spatial domain. Based on the choice of transformation, small regions of high error can be present as a result of the variable source position.

A Review on the Separation of Volatile Organic Compounds from Wastewater by Pervaporation Processes

The pervaporation process (PV) is one of the membrane separation methods. This process is characterized by low cost, ease of installation, no chemicals added, and work at medium temperatures. The pervaporation process is part of a chain of water treatment processes and has high efficiency in removing pollutants, drying processes, and others. The present review paper would be reviewed the related articles to show the efficiency of the separation of the solution by the pervaporation process by focusing on research that deals with the separation of volatile organic compounds (VOCs) from water such as benzene and toluene. Benzene compound was used to prepare some of the chemicals such as styrene, phenol, cyclohexane, aniline, and polyester resins. Also, it is used in the production of drugs, dyes, insecticides, and plastics, moreover, it is produced from the refineries' operations and mixes with the water used in these operations, where its concentration reaches up to 16 ppm. While toluene is a common solvent used for paints, glues, and printing ink. Toluene compound is produced from the refineries operations and mixes with the water used in these operations, where its concentration reaches up to 55 ppm, where these percentages for benzene and toluene are considered high and very dangerous to humans and the environment which causes many carcinogenic diseases. Also, researchers would be reviewing that worked on developing various types of membranes by adding different materials to improve membrane performance and increase the desired flux of components and separation factors with different working conditions.

Development of continuous V-shaped structure for high heat flux components of flat-type divertor

The continuous V-shaped structure with hypervapotron for divertor target can improve the cooling performance and detachment in the strike point area. The design and manufacture of this structure has been described in this work. The continuous V-shaped structure in a flat-type divertor is beneficial for divertor detachment because it has a deep slot that can trap neutral particles. The target cooled by hypervapotron is designed to sustain stationary heat flux up to ∼ 10 MW· m−2. The hypervapotron structure is directly connected at the root of the V configuration and expands the potential candidate area of the strike point for better adaptability to different plasma configurations. The simulation results demonstrate that temperature of the structure meets the allowance values of the materials because the strike point hits at the inner tip of V-shaped structure, i.e. the extreme point. The heat-sink composite panel used is made of CuCrZr and 316L stainless steel and is formed by explosive welding. The V-shaped structure is made by bending, machining, and brazing. Finally, three continuous V-shaped structure mockups were fabricated and tested to demonstrate the feasibility of engineering design.

Using cultured canine cardiac slices to model the autophagic flux with doxorubicin.

Chemotherapy-induced impairment of autophagy is implicated in cardiac toxicity induced by anti-cancer drugs. Imperfect translation from rodent models and lack of in vitro models of toxicity has limited investigation of autophagic flux dysregulation, preventing design of novel cardioprotective strategies based on autophagy control. Development of an adult heart tissue culture technique from a translational model will improve investigation of cardiac toxicity. We aimed to optimize a canine cardiac slice culture system for exploration of cancer therapy impact on intact cardiac tissue, creating a translatable model that maintains autophagy in culture and is amenable to autophagy modulation. Canine cardiac tissue slices (350 μm) were generated from left ventricular free wall collected from euthanized client-owned dogs (n = 7) free of cardiovascular disease at the Foster Hospital for Small Animals at Tufts University. Cell viability and apoptosis were quantified with MTT assay and TUNEL staining. Cardiac slices were challenged with doxorubicin and an autophagy activator (rapamycin) or inhibitor (chloroquine). Autophagic flux components (LC3, p62) were quantified by western blot. Cardiac slices retained high cell viability for >7 days in culture and basal levels of autophagic markers remained unchanged. Doxorubicin treatment resulted in perturbation of the autophagic flux and cell death, while rapamycin co-treatment restored normal autophagic flux and maintained cell survival. We developed an adult canine cardiac slice culture system appropriate for studying the effects of autophagic flux that may be applicable to drug toxicity evaluations.

Carbon stocks and fluxes in Asia-Pacific mangroves: current knowledge and gaps

Mangrove forest plays a key role in regulating climate change, earth carbon cycling and other biogeochemical processes within blue carbon ecosystems. Therefore, mangrove forests should be incorporated into Earth system climate models with the aim of understanding future climate change. Despite multiple carbon stock and flux assessments taking place over the past couple of decades, concrete knowledge of carbon source/sink patterns is largely lacking, particularly in the biodiversity-rich Asia-Pacific (AP) region with its 68 493 km2 of mangrove area. Thus, to understand the gaps in mangrove blue carbon research in the AP region, we summarize a recent decade-long inventory of carbon stock pools (aboveground, belowground and soil) and biogeochemical flux components (burial, export/import, soil-air and water-air CO2 flux) across 25 AP countries to understand the current knowledge and gaps. While carbon stock assessments of individual components are available for all 25 countries, whole ecosystem carbon stocks—including live and standing dead aboveground and belowground, downed woody debris and soil carbon stocks—are often lacking, even in highly researched countries like Indonesia. There is restricted knowledge around biogeochemical carbon fluxes in 55% of the countries, suggesting poor carbon flux research across the region. Focusing on flux components, reports on sediment-to-sea carbon exports are extremely limited (coming from just nine countries in the AP region). There is notable scarcity of data on carbon export fluxes in Indonesian mangroves. Given the key role AP mangroves play in climate change mitigation worldwide, more detailed and methodologically comparable investigation of biogeochemical source/sink processes is required to better understand the role of this large carbon source in global carbon stocks and fluxes, and hence, global climate.

Intercomparison of Atmospheric Carbonyl Sulfide (TransCom‐COS; Part One): Evaluating the Impact of Transport and Emissions on Tropospheric Variability Using Ground‐Based and Aircraft Data

AbstractWe present a comparison of atmospheric transport model (ATM) simulations for carbonyl sulfide (COS), within the framework of the atmospheric tracer transport model intercomparison project “TransCom‐COS.” Seven ATMs participated in the experiment and provided simulations of COS mixing ratios over the years 2010–2018, using state‐of‐the‐art surface fluxes for various components of the COS budget: biospheric sink, oceanic source, sources from fire and industry. The main goal of TransCom‐COS is to investigate the impact of the transport uncertainty and emission distribution in simulating the spatio‐temporal variability of tropospheric COS mixing ratios. A control case with seasonal surface fluxes of COS was constructed. The results indicate that the COS mixing ratios are underestimated by at least 50 parts per trillion (ppt) in the tropics, pointing to a missing tropical source. In summer, the mixing ratios are overestimated by at least 50 ppt above 40°N, pointing to a likely missing sink in the high northern latitudes. Regarding the latitudinal profile, the model spread is greater than 60 ppt above 40°N in boreal summer. Regarding the seasonal amplitude, the model spread reaches 50 ppt at 6 out of 15 sites, compared to an observed seasonal amplitude of 100 ppt. All models simulated a too late minimum by at least 2–3 months at two high northern‐latitude sites, likely owing to errors in the seasonal cycle in the ocean emissions. This study highlighted the shortcomings in the COS global budget that need to be resolved before using COS as a photosynthesis tracer.

Mass Transfer through Vapor–Liquid Interfaces Studied by Non-Stationary Molecular Dynamics Simulations

Molecular dynamics (MD) simulations are highly attractive for studying the influence of interfacial effects, such as the enrichment of components, on the mass transfer through the interface. In a recent work, we have presented a steady-state MD simulation method for investigating this phenomenon and tested it using model mixtures with and without interfacial enrichment. The present study extends this work by introducing a non-stationary MD simulation method. A rectangular simulation box that contains a mixture of two components 1 + 2 with a vapor phase in the middle and two liquid phases on both sides is used. Starting from a vapor-liquid equilibrium state, a non-stationary molar flux of component 2 is induced by inserting particles of component 2 into the center of the vapor phase in a pulse-like manner. During the isothermal relaxation process, particles of component 2 pass through the vapor phase, cross the vapor-liquid interface, and enter the liquid phase. The system thereby relaxes into a new vapor-liquid equilibrium state. During the relaxation process, spatially resolved responses for the component densities, fluxes, and pressure are sampled. To reduce the noise and provide measures for the uncertainty of the observables, a set of replicas of simulations is carried out. The new simulation method was applied to study mass transfer in two binary Lennard-Jones mixtures: one that exhibits a strong enrichment of the low-boiling component 2 at the vapor-liquid interface and one that shows no enrichment. Even though both mixtures have similar transport coefficients in the bulk phases, the results for mass transfer differ significantly, indicating that the interfacial enrichment influences the mass transfer.

Long-term temporal patterns in ecosystem carbon flux components and overall balance in a heathland ecosystem

Terrestrial ecosystems have strong feedback to atmospheric CO2 concentration and climate change. However, the long-term whole life cycle dynamics of ecosystem carbon (C) fluxes and overall balance in some ecosystem types, such as heathland ecosystems, have not been thoroughly explored. We studied the changes in ecosystem CO2 flux components and overall C balance over a full ecosystem lifecycle in stands of Calluna vulgaris (L.) Hull by using a chronosequence of 0, 12, 19 and 28 years after vegetation cutting. Overall, the ecosystem C balance was highly nonlinear over time and exhibited a sinusoidal-like curvature of C sink/source change over the three-decade timescale. After cutting, plant-related C flux components of gross photosynthesis (PG), aboveground autotrophic respiration (Raa) and belowground autotrophic respiration (Rba) were higher at the young age (12 years) than at middle (19 years) and old (28 years) ages. The young ecosystem was a C sink (12 years: −0.374 kg C m−2 year−1) while it became a C source with aging (19 years: 0.218 kg C m−2 year−1) and when dying (28 years: 0.089 kg C m−2 year−1). The post-cutting C compensation point was observed after four years, while the cumulative C loss in the period after cutting had been compensated by an equal amount of C uptake after seven years. Annual ecosystem C payback from the ecosystem to the atmosphere started after 16 years. This information may be used directly for optimizing vegetation management practices for maximal ecosystem C uptake capacity. Our study highlights that whole life cycle observational data of changes in C fluxes and balance in ecosystems are important and the ecosystem model needs to take the successional stage and vegetation age into account when projecting component C fluxes, ecosystem C balance, and overall feedback to climate change.

Complementary collider and astrophysical probes of multi-component Dark Matter

We study a new physics scenario with two inert and one active scalar doublets, hence a 3-Higgs Doublet Model (3HDM). We impose a {Z}_2times {Z}_2^{prime } symmetry onto such a 3HDM with one inert doublet odd under the Z2 transformation and the other odd under the {Z}_2^{prime } one. Such a construction leads to a two-component Dark Matter (DM) model. It has been shown that, when there is a sufficient mass difference between the two DM candidates, it is possible to probe the light DM candidate in the nuclear recoil energy in direct detection experiments and the heavy DM component in the photon flux in indirect detection experiments. With the DM masses at the electroweak scale, we show that, independently of astrophysical probes, this model feature can be tested at the Large Hadron Collider via scalar cascade decays in final states. We study several observable distributions whose shapes hint at the presence of the two different DM candidates.

Preparation of CFB fly ash/sewage sludge ceramsite and the morphological transformation and release properties of sulfur

In order to improve the resource utilization of circulating fluidized bed (CFB) fly ash and sewage sludge, light-weight and high-strength CFB fly ash/sewage sludge ceramsite (CFBS ceramsite) was prepared by using CFB fly ash and original wet sludge as the main raw materials. The effects of dosages of CFB fly ash, sewage sludge, fluxing agent, and foaming agent and sintering temperature on the physical and mechanical properties of CFBS ceramsite were studied by single factor experiment method. Using SEM, XRD, sulfur analyzer, TG-DSC, flue gas analyzer, TG-MS and XPS analyses, the micro morphology and mineral composition of CFBS ceramsite were studied, and the morphological transformation and release properties of sulfur were also revealed. The results show that the optimal preparation conditions are: the mass ratio [CFB fly ash: sludge] = [65 %∼80 %: 35 %∼20 %], addition of 10 % glass powder, addition of 2.5 %∼10 % calcium carbonate, and sintering at 1200 ∼ 1250℃ for 15 ∼ 20 min. The resulting CFBS ceramsite can be obtained with bulk density of 750 ∼ 850 kg/m3, water absorption of 0.27 %∼0.94 % and cylinder compressive strength of 5.11 ∼ 7.86 MPa. Sulfur in the CFBS ceramsite is mainly derived from organic sulfur in the sewage sludge and inorganic sulfur in the CFB fly ash, and it exists in the form of sulfate and sulfide when the sintering temperature exceeds 400℃. The sulfur content of the final prepared CFBS ceramsite is 0.0217 wt%. Decomposition of SO2 from the anhydrite in CFB fly ash is the main reason for the swelling and foaming of the CFBS ceramsite. However, calcium carbonate, derived from either sulfur-fixing agent in CFB fly ash or auxiliary foaming agent, cannot play the role of foaming agent, while the CaO decomposed from calcium carbonate increases the content of fluxing component in the ceramsite and finally affects the properties of CFBS ceramsite.