Dust Burning Research Articles

Physical modeling of the M-shaped boiler furnace aerodynamics

In order to increase the thermodynamic efficiency of the Rankine cycle, in Russia, China, the USA, and EU countries, new-generation power units with advanced ultra-supercritical (A-USC) steam parameters are being developed. Using A-USC steam parameters (temperature – 700-760 °C, pressure – 35 MPa) will lead to the need to use expensive nickel steels. A single-shell design of the M-shaped boiler for burning Kuznetsk coal grade TP with solid slag removal (SSR) was proposed to reduce the total length of the main steam pipelines. A solid fuel combustion scheme with direct-flow burners, nozzles and system of vertical-horizontal tangential flames (VHTF) has been developed for this boiler, which will ensure: emissions of nitrogen oxides into the atmosphere at a level lower than standard; continuous operation of the boiler in the absence of slagging of the furnace walls and overheating of the pipe metal; a high degree of burnout of coal dust, with the provision of the standard value of the mechanical underburning of fuel; long minimum boiler load at a level not exceeding 40% of the nominal one according to the conditions of coal dust combustion stability.

Seasonal Variation of Carbonaceous Species of PM2.5 in a Small City in Sichuan Basin, China

Organic carbon (OC) and elemental carbon (EC) concentrations were measured in daily PM2.5 samples collected over four non-consecutive months representing four seasons from 2016 to 2017 in a small city in the east of Sichuan Basin. The average concentrations of OC and EC during the study periods were observed to be 15.5 ± 13.5 and 5.2 ± 4.7 μg∙m−3, respectively, both with the highest in winter. The OC and EC correlated well in fall and winter, implying that OC and EC were attributed to common emission sources. The estimated secondary OC (SOC) represented 37.2%, 46.7%, 26.9%, and 40.7% of the OC in spring, summer, fall, and winter, respectively. The highest concentration of SOC was found in winter, while the proportion of SOC/OC was highest in summer. Strong correlations were observed between OC vs. K+ and EC vs. K+ in fall and winter, suggesting that biomass burning was a significant source of carbonaceous aerosols. Four sources of OC and EC were resolved by the positive matrix factorization (PMF) model, including coal combustion (5.5% and 12.1%), building and road dust (19.7% and 18.1%), biomass burning (38.7% and 33.1%), and vehicle emission (36.1% and 36.7%), respectively. The potential source contribution function (PSCF) analysis signified that the main source areas of OC and EC were distributed in or nearby Wanzhou.

NFPA 652: The gap between industry's understanding and compliance

AbstractThe requirements of NFPA 652 Standard regarding Dust Hazard Analysis on the Fundamentals of Combustible Dust had to be fully implemented in 2020. In this article, we present the results of a survey that tested how well those with responsibility for NFPA 652 compliance have understood its requirements. We find that although there is a good level of understanding about what is required there are never‐the‐less a number of areas where the standard has been misunderstood.

Expansion of a size disaggregation profile library for particulate matter emissions processing from three generic profiles to 36 source-type-specific profiles

ABSTRACT This study describes a significant upgrade to the particulate matter (PM) size disaggregation profile library used for preparing emissions files for the GEM-MACH (Global Environmental Multiscale-Modelling Air-quality and CHemistry) chemical transport model (CTM). This model uses a sectional (bin) approach to represent the PM size distribution, where one configuration employs 12 size bins to disaggregate PM2.5 and PM10 inventory emissions into the first 10 bins ranging from 0.01 to 10.24 μm in diameter. For the size disaggregation step, a small library of three generic PM size disaggregation profiles is currently applied for three broad source categories (area, mobile, and point). However, as might be expected, these generic profiles are not always representative: for example, emissions from two very different area sources ‒ paved road dust and residential wood combustion ‒ are disaggregated using the same generic size distribution profile. In order to improve the current small PM size disaggregation profile library, a comprehensive literature review was conducted: over 100 relevant publications were identified and PM size distribution profiles for 36 different emission source types were selected and compiled. These 36 source-type-specific PM size distribution profiles were then combined based on process type with corresponding PM speciation profiles to create a library of chemically speciated and size-resolved PM disaggregation profiles. This library can now be used by the SMOKE (Sparse Matrix Operator Kernel Emissions) emissions processing system for the 12-bin version of GEM-MACH to perform PM chemical speciation and size allocation in one step. The size-profile data collected and compiled in this study may also be used for emissions processing for other CTMs with a size-resolved representation of PM. Details of the compilation of the 36 PM size disaggregation profiles are discussed, and the differences in processed PM emissions based on the current and updated PM size disaggregation profile libraries are shown. Implications: A new and expanded particulate matter (PM) size disaggregation profile library covering 36 emission source types has been developed based on an extensive literature review. Its use can produce significant changes in the size allocation of bulk PM inventory emissions processed for input to size-resolved PM chemical transport models. Such models are used to predict atmospheric visibility and to simulate the interactions of aerosol particles with atmospheric radiation and with clouds. The use of more accurate, size-resolved primary PM emissions by these models should improve their predictive skill for atmospheric PM processes affecting air quality, meteorology, and climate.

Chemical formation and source apportionment of PM2.5 at an urban site at the southern foot of the Taihang mountains

The region along the Taihang Mountains in the North China Plain (NCP) is characterized by serious fine particle pollution. To clarify the formation mechanism and controlling factors, an observational study was conducted to investigate the physical and chemical properties of the fine particulate matter in Jiaozuo city, China. Mass concentrations of the water-soluble ions (WSIs) in PM2.5 and gaseous pollutant precursors were measured on an hourly basis from December 1, 2017, to February 27, 2018. The positive matrix factorization (PMF) method and the FLEXible PARTicle (FLEXPART) model were employed to identify the sources of PM2.5. The results showed that the average mass concentration of PM2.5 was 111 μg/m3 during the observation period. Among the major WSIs, sulfate, nitrate, and ammonium (SNA) constituted 62% of the total PM2.5 mass, and NO3− ranked the highest with an average contribution of 24.6%. NH4+ was abundant in most cases in Jiaozuo. According to chemical balance analysis, SO42−, NO3−, and Cl− might be present in the form of (NH4)2SO4, NH4NO3, NH4Cl, and KCl. The liquid-phase oxidation of SO2 and NO2 was severe during the haze period. The relative humidity and pH were the key factors influencing SO42- formation. We found that NO3− mainly stemmed from homogeneous gas-phase reactions in the daytime and originated from the hydrolysis of N2O5 in the nighttime, which was inconsistent with previous studies. The PMF model identified five sources of PM2.5: secondary origin (37.8%), vehicular emissions (34.7%), biomass burning (11.5%), coal combustion (9.4%), and crustal dust (6.6%).

Source identification of particulate phosphorus in the atmosphere in Beijing

We tracked atmospheric phosphorus (P) in suspended particulate matter (PM) from a site in Beijing, China over a three-year period and found a new relationship between plants and atmospheric P. Concentrations of total phosphorus (TP) in the atmosphere during plant growing seasons were 2.5 times those observed in other months and levels of organic phosphorus (OP) were 3.9 times as high. TP and OP increases during growing seasons were much more significant in PM with diameters of over 2.5 μm (PM>2.5). PM collected during growing seasons included high levels of P but less nitrogen than that in primary biogenic aerosol particles (PBAPs) and differed from other emission sources such as combustion emissions and dust. A time series of OP concentrations in the atmosphere shows a time lag relative to Normalized Difference Vegetation Index (NDVI) data with high levels found during early growing periods and much lower levels found during flourishing periods. Thus, we find that plants contribute to atmospheric P and especially to OP rather than to PBAP levels.

Chemical characterization and source apportionment of fine and coarse atmospheric particulate matter in Doha, Qatar

Atmospheric particulate matter of two size fractions (i.e., PM2.5 and PM10) were sampled simultaneously at an urban site in Doha, Qatar, and characterized to measure chemical constituents (including trace elements, organic and elemental carbon (OC/EC), and water-soluble ions). The composition data were applied to mass closure analysis and Positive Matrix Factorization (PMF) model along with detailed wind direction analysis for quantifying and identifying the probable sources of both PM size fractions. The average concentrations of PM2.5 (40 μg m−3) and PM10 (146 μg m−3) were greatly exceeded the WHO air quality thresholds for 78–92% of the sampling days. Mass closure indicated the predominance of secondary inorganic aerosol (39%) and EC (7%) in fine PM, while mineral dust contributes 50% to the total mass of coarse particles. PMF identified six major sources of fine and coarse PM, including secondary inorganic aerosols, vehicular emissions, heavy oil combustion, marine aerosols, mineral and fugitive dust. The wind direction analysis indicated that both local and regional sources impact Qatar's air quality attributed to specific wind conditions. Two main sources of heavy oil combustion and secondary aerosols are closely related to regional emissions from shipping vessels and the petrochemical industry in the Gulf region. The desert dust transport mixed with local re-suspended dust and sea-salt particles also contributes considerably to the local PM concentrations. The significant contributions of regional anthropogenic and natural emissions pose a significant challenge in meeting local PM standards, signifying the importance of regional collaboration for better control policies on reducing transboundary air pollution.

Chemical compositions and the impact of sea salt in atmospheric PM1 and PM2.5 in the coastal area

The 11.5-h samples were collected at a coastal site and an urban site in the coastal area, Qingdao. PM1- and PM2.5-bound water-soluble inorganic ions (WSIIs), organic carbon (OC) and element carbon (EC) were analyzed in January and July 2019. PM2.5-bound elements were determined in July 2019. The results showed that the ∑WSIIs, OC and EC concentrations at the coastal site were significantly lower than those at the urban site, and their concentrations in winter were significantly higher than those in summer. Sea salt concentrations in PM2.5 were significantly higher than those in PM1 and were significantly correlated with the concentrations of secondary inorganic aerosol (SIA) and secondary organic carbon (SOC). The mean concentrations of total elements were 1258.35 ± 1033.43 and 1669.27 ± 808.53 ng m−3 at the coastal site and urban site, respectively. The health risk assessments for elements implied that the total non-carcinogenic risks via inhalation can be ignored and the total carcinogenic risks were within an acceptable level. Positive matrix factorization model (PMF) indicated secondary inorganic aerosols (31.13%), biomass burning (28.98%), aged sea salt (21.60%), coal combustion (10.91%) and crustal dust (7.39%) were major sources of WSIIs, OC and EC. Coal and biomass burning sources played more obvious roles at the urban site in winter but secondary inorganic aerosols and aged sea salt made more apparent contributions at the coastal site. The contribution of aged sea salt source was significantly increased from winter to summer. While the contributions of secondary inorganic aerosols, biomass burning, coal combustion and crustal dust were decreased. The concentration-weighted trajectory (CWT) model suggested that local areas from Shandong Province were important for secondary inorganic aerosols, biomass burning and coal combustion. The major source regions of aged sea salt source were the Yellow Sea, Jiangsu, Anhui and Eastern Shandong Provinces. Crustal dust was dominantly originated from Western Shandong Province.

Light absorption enhancement of particulate matters and their source apportionment over the Asian continental outflow site and South Yellow Sea.

Light absorption enhancement of black carbon due to the aerosol mixing states is an important parameterization for climate modeling, while emission source contributions to the enhancement factor are unclear. An intensive campaign was conducted simultaneously at a China coastal site (Qingdao city) and maritime sites (South Yellow Sea, SYS) in August and Nov to Dec 2018. The absorption enhancement (EMAC) of the black carbon was calculated using a two-step solvent dissolution protocol and found 1.96 ± 0.68, 1.64 ± 0.38, and 2.40 ± 0.76 for Qingdao summer (QS), Qingdao autumn (QA), and SYS, respectively. Positive matrix factorization (PMF) model identified six sources of PM2.5 and EMAC, which were secondary aerosol (with contribution 27.9% and 29.2%), coal combustion (24.9% and 20.2%), industrial emissions (15.2% and 25.4%), sea salt (6.9% and 9.6%), vehicle emissions (12.1% and 10.9%), and soil dust (13.0% and 4.7%), respectively. These sources increased the absorption of black carbon by a factor of 1.25 ± 0.11 (secondary aerosol), 1.21 ± 0.20 (industrial emissions), 1.17 ± 0.08 (coal combustion), 1.09 ± 0.07 (vehicle emissions), 1.08 ± 0.17 (sea salt), and 1.04 ± 0.10 (soil dust). Based on the correlation between PM and EMAC source contributions, we estimated that secondary aerosols, industrial emissions, and coal combustion contributed to 74.8% of absorption enhancement at a regional scale in China. The source apportionment for EMAC offers a new diagnosis for each source regarding aerosol forcing simulation which inputs from the individual emission sector.

Influential factors on the explosibility of unpremixed hydrogen/magnesium dust

The explosibility of unpremixed hydrogen/magnesium dust in a confined space was simulated and studied using a cubic explosion chamber. Typical influential factors, including hydrogen content in air, depth of magnesium layer, particle size distribution, ambient humidity, initial gas pressure and ignition position, on the explosion pressures of unpremixed hydrogen/magnesium dust in the first and secondary explosions were investigated. Experimental results showed that the biggest peak pressure values in the first and secondary explosions of the unpremixed hydrogen/magnesium dust were both obtained when the hydrogen content was 50%, and nitrogen participated the combustion of magnesium dust in the dust explosion. The effects of magnesium layer depth on the change trend of peak pressure in the first explosion was different from that in the secondary explosion for the unpremixed hydrogen/magnesium dust with a lean hydrogen concentration, and mean particle size of magnesium dust had a significant effect on the explosion pressure. Peak pressures in the first and secondary explosions both presented a trend of increasing at the early stage and then decreased with the increasing humidity or gas pressure, and the combustion mode of the unpremixed hydrogen/magnesium dust varied as the ignition position was changed.

Effects of dust dispersibility on the suppressant enhanced explosion parameter (SEEP) in flame propagation of Al dust clouds

This work presents an overview about the suppressant enhanced explosion parameter (SEEP) phenomenon in aluminum dust explosion moderation. The SEEP phenomenon can be attributed to either the flammable gas produced by decomposition of insufficient chemical suppressant so as to form an explosible hybrid mixture, or to the improvement in dust dispersibility caused by small amounts of thermal inhibitor so as to form better dispersed dust clouds. Aluminum (Al) and four particle sizes of alumina (Al2O3) were used to confirm a physically caused SEEP phenomenon by performing flame propagation experiments. Higher flame spread velocities (FSVs) in Al dust clouds were found in the presence of 5 or 10% <150 and <45-µm Al2O3 powder. Adding micro-sized Al2O3 disrupted inter-particle contact in combustible dusts, decreased inter-particle forces, and formed dust clouds with better dispersibility, thereby decreasing the effective particle size distribution (PSD) of Al dust. A strong thermal effect brought about by 2.5 µm Al2O3 overcame the negative effect of improved dispersion, preventing SEEP from occurring. The addition of 50 nm Al2O3 increased cohesion of powder mixtures, and decreased dust dispersibility. With benefits from both dispersion suppression and the thermal effect, Al flame propagation was well quenched.

Numerical study on premixing characteristics and explosion process of starch in a vertical pipe under turbulent flow

Fire and explosion accidents are frequently caused by combustible dust, which has led to increased interest in this area of research. Although scholars have performed some research in this field, they often ignored interesting phenomena in their experiments. In this paper, we established a 2D numerical method to thoroughly investigate the particle motion and distribution before ignition. The optimal time for the corn starch dust cloud to ignite was determined in a semi-closed tube, and the characteristics of the flame propagation and temperature field were investigated after ignition inside and outside the tube. From the simulation, certain unexpected phenomena that occurred in the experiment were explained, and some suggestions were proposed for future experiments. The results from the simulation showed that 60–70 ms was the best time for the dust cloud to ignite. The local high-temperature flame clusters were caused by the agglomeration of high-temperature particles, and there were no flames near the wall of the tube due to particles gathering and attaching to the wall. Vortices formed around the nozzle, where the particle concentration was low and the flame spread slowly. During the explosion venting, particles flew out of the tube before the flame. The venting flame exhibited a “mushroom cloud” shape due to interactions with the vortex, and the flame maintained this shape as it was driven upward by the vortex.

Technical textiles for protection against Arc-flash fire: Savesplash®

Flash fire caused by electric arc is different than that caused by flammable liquids/fumes or combustible dusts. A suitable protective clothing for protection against electric arc-flash must be designed as per Indian weather conditions. Currently available garments are manufactured using two or three layers of woven/nonwoven combinations to achieve higher Hazard Risk Category (HRC) rating (level 3 and above). However, they are heavy and not comfortable to the end users. Savesplash® is a single layer inherent flame-retardant knitted fabric. Its arc rating was determined using ASTM standards. It achieved arc thermal performance value (ATPV) of 41 cal/cm2, breakopen threshold energy (E_BT) of 42 cal/cm2 and heat attenuation factor (HAF) of 94% when tested as per ASTM F1959/F1959M-14 which translated into an arc rating of 41 cal/cm2. This is equivalent to HRC level 4 ratings as per National Fire Protection Association’s NFPA 70E standard (USA). Further, cut and sewn gloves (HM-100) developed using Savesplash® fabric reinforced with leather on palm area achieved ATPV of 63 cal/cm2 and HAF of 94.5% when tested as per ASTM F2675/F2675M-13.

Determination of conditions for spontaneous combustion of combustible dust deposits on equipment, in ventilation systems, and aspiration systems of buildings and structures

Introduction. Determination of the scientifi cally substantiated frequency of cleaning the ducts of local exhausts of industrial buildings and structures is one of the tasks in the fi eld of fi re safety of industrial enterprises. The paper describes design methods, in particular, a method for determination of the induction period during spontaneous combustion of dust deposits in air ducts of ventilation systems and equipment, which can be used in solving problems focused on the development of preventive measures to ensure their fi re and explosion safety.Methods. In order to solve the problem set in this paper and compare the indicators obtained in the calculation and analytical part of the studies with the growth dynamics of deposits in real facilities, fi eld tests have been accomplished in the production facilities of the fl our mill of OJSC MK “Voronezhsky” and JSC Concern “Sozvezdiye”.Results and discussion. The timeframes for cleaning of deposits on ventilation (aspiration) equipment of buildings and structures cannot be universal for various industries and must take into account the dynamics of the growth of deposits depending on the specifi cs of combustible deposits, the workload of the production facilities of the protected object in a given period of time, and the operating conditions of the equipment. As a result of the experiments, it was found that the places of maximum accumulations of deposits are most often formed on the surfaces of joints and on the bends of pipelines of ventilation systems. The conditions of spontaneous combustion of combustible dust are studied by calculation and analytical method, depending on such process characteristics as the speed of the dust-air mixture fl ow in the duct, as well as the diameter of the duct’s cross section.Conclusions. The nomograms built on the basis of the studies performed can be used to determine the multiplicity of cleaning of combustible dusts of equipment and air ducts of industrial ventilation systems. The paper provides a calculation of the period of induction of spontaneous combustion of combustible dust deposits using the example of rye fl our with asymmetric heat transfer. Its signifi cance is due to the process of accumulation of deposits of combustible dust to a critical thickness in terms of spontaneous combustion conditions.

High-speed digital in-line holography for in-situ dust cloud characterization in a minimum ignition energy device

Precise measurement of the minimum ignition energy (MIE) of combustible dust is crucial to safety in the process industries. The development of comprehensive methods for MIE dust cloud characterization is therefore highly desirable. The objective of this study is to investigate the application of high-speed digital in-line holography (DIH) for volumetric and in-situ characterization of dust clouds near the ignition zone of a Kühner MIKE3 MIE device. The dispersion behavior of borosilicate glass and soda-lime glass dust clouds are studied at 20 kHz. Size measurements, with successful detection down to 13 μm, are compared with Beckman Coulter particle size analyzer results. The 5-ms hologram videos also yield new transient particle volume, concentration, and velocity measurements. Sample sizes of 15–150 mg of dust powder are sufficient for each high-speed run. This work showcases new diagnostic capabilities that are accessible to dust explosion research and identifies areas for future research.

Multi-city comparative PM2.5 source apportionment for fifteen sites in Europe: The ICARUS project

PM2.5 is an air pollution metric widely used to assess air quality, with the European Union having set targets for reduction in PM2.5 levels and population exposure. A major challenge for the scientific community is to identify, quantify and characterize the sources of atmospheric particles in the aspect of proposing effective control strategies. In the frame of ICARUS EU2020 project, a comprehensive database including PM2.5 concentration and chemical composition (ions, metals, organic/elemental carbon, Polycyclic Aromatic Hydrocarbons) from three sites (traffic, urban background, rural) of five European cities (Athens, Brno, Ljubljana, Madrid, Thessaloniki) was created. The common and synchronous sampling (two seasons involved) and analysis procedure offered the prospect of a harmonized Positive Matrix Factorization model approach, with the scope of identifying the similarities and differences of PM2.5 key-source chemical fingerprints across the sampling sites. The results indicated that the average contribution of traffic exhausts to PM2.5 concentration was 23.3% (traffic sites), 13.3% (urban background sites) and 8.8% (rural sites). The average contribution of traffic non-exhausts was 12.6% (traffic), 13.5% (urban background) and 6.1% (rural sites). The contribution of fuel oil combustion was 3.8% at traffic, 11.6% at urban background and 18.7% at rural sites. Biomass burning contribution was 22% at traffic sites, 30% at urban background sites and 28% at rural sites. Regarding soil dust, the average contribution was 5% and 8% at traffic and urban background sites respectively and 16% at rural sites. Sea salt contribution was low (1–4%) while secondary aerosols corresponded to the 16–34% of PM2.5. The homogeneity of the chemical profiles as well as their relationship with prevailing meteorological parameters were investigated. The results showed that fuel oil combustion, traffic non-exhausts and soil dust profiles are considered as dissimilar while biomass burning, sea salt and traffic exhaust can be characterized as relatively homogenous among the sites.

CFD Modeling of Ventilation and Dust Flow Behavior in Polishing and the Design of an Innovative Wet Dust Removal System.

Fine aluminum dust pollution in the polishing process was detected during a field survey. To obtain a fundamental understanding of the airflow patterns and the fine dust dispersion characteristics during a polishing process, computational fluid dynamics simulations were first performed to analyze the data collected in field measurements. The inappropriate ventilation arrangement and lack of effective dust control measures were identified as the main reasons for the high dust exposure levels (in excess of 1000 μg/m3). Simulation results showed that inhalable dust particles (PM10) could be significantly diluted at the operator’s breathing level by adding a supply air inlet above the operating area. Moreover, dry dust collection systems create a risk of aluminum dust explosion accidents. An innovative design of wet dust removal system which could mitigate the occurrence of dust explosions was proposed and then implemented on site. An independent field dust assessment showed that a reduction of fine dust particles up to 95% in the worker’s breathing area and the fine dust in the vents was reduced to 80%. Therefore, the proposed strategies are implemented immediately to address the combustible dust in the polishing working environment and can provide guidance for operators.

Comminution of pulverized Pittsburgh coal during ASTM E1226-12a dust combustibility testing

Combustible dusts present an industrial hazard due to their ability to react rapidly and generate dust explosions. Studies have shown that processes utilized to inject and disperse dust particles within combustible dust testing devices result in further comminution of tested materials. Dust explosions are quantified by characteristics Pmax, (dP/dt)max, and Kst-max. This paper investigates the change in physical dust parameters of pulverized Pittsburgh coal, a certification material for ASTM E1226, after dispersion into a Siwek 20-Liter apparatus. Experiments indicate that the change in dust particle size and distribution varies with concentration. Smaller quantities of dust undergo higher levels of comminution. In the case of pulverized Pittsburgh coal all concentrations dispersed had more fines and smaller D10, D50(median), and D90 particle sizes than the pre-dispersion feedstock. Some samples had over a 50% decrease in particle size for D10, D50(median), and D90 which can affect engineering and risk assessment calculations

Effect of admixed silica on dispersibility of combustible dust clouds in a Godbert-Greenwald furnace

Dust dispersibility, the tendency of dust to form clouds that remain airborne, can be an important safety parameter in preventing dust explosion. One measure to moderate dust explosion hazards is adding solid inertants to combustible dust. In addition to being a solid inertant, noncombustible silica is sometimes used as an anti-caking agent or fluidization enhancement additive in powder systems, affecting particle interactions in dust clouds. In this study, six types of combustible dust were admixed with micro- and nano-sized silica to study the effect on dispersibility and ignition hazard in a Godbert-Greenwald (G-G) furnace. Both micro- and nano-silica increased dispersion for some dust types, by changing contact geometry between combustible particles, and thereby decreasing inter-particle forces. Only for polyethylene did addition of 1% micro-silica cause increased dispersibility resulting in enhanced ignition hazard, with minimum ignition temperature (MIT) slightly decreasing 10 °C. No reduced MIT values were found with 1% nano-silica.

Characteristics of wheat dust flame with the influence of ceramic foam

A vertical dust combustion pipeline with high-speed photography, micro-thermocouple and pressure sensor was built to investigate the influence of ceramic foam on the wheat dust explosion flame. Ceramic foams with different parameters were adopted in this paper, and compared with metal mesh. The chemical structures of dust explosion residue were characterized by X-ray photoelectron spectroscopy. Results indicate that the wheat dust flame propagation and structure were significantly destroyed by ceramic foam. With the decreasing aperture or increasing layer, the blocking effect of ceramic foam was aggravated on the dust flame. The flame cannot pass through the ceramic foam with 20 PPI and 3 layers. On the upper end of ceramic foam, the flame temperature is positively proportional to the aperture but inversely proportional to the layers. With the PPI and layers of ceramic foam increases, the combustion pressure firstly increases and then decreases when the dust combustion intensity is strong. Ceramic foam shows the incentive effect to some extent on the combustion pressure, but the continuous inhibition effect is found for the metal mesh.