Oil Smoke Research Articles

Design of self-cleaning low-temperature plasma fume cleaning device based on computational fluid dynamics

Abstract With the rapid development of the catering industry, catering fume pollution has become one of the important sources of urban air pollution. How to realize the purification of catering fumes is a huge problem related to public life health and safety. This paper first constructs the structure of self-cleaning low-temperature plasma soot purification and provides the equipment, materials, and process required for soot purification experiments. Secondly, CFD simulation of the flue of the oil smoke purification device is introduced into Computational Fluid Dynamics, and the relevant physical parameters of the oil smoke flow are obtained by solving the equations of mass conservation, momentum conservation and energy conservation. The self-cleaning low-temperature plasma oil smoke purification device was also analyzed by numerical simulation using Fluent software, and the method for detecting VOCs in restaurant oil smoke was given. Lastly, the oil smoke purification device constructed in this paper was tested for its impact on oil smoke. The results show that for every 100W·m−2 increase in the intensity of oil smoke, the temperature error will increase by about 0.01℃ accordingly, and when the intensity of oil smoke reaches 500W·m−2, the temperature error of the oil smoke purification device is 0.074℃. The highest imported concentration of all kinds of VOCs in the barbecue smoke produced by the experiment reached 3762.53 μg / m 3, and the average treatment efficiency of 98.69% was achieved under the actual air volume of about 800m3/h. This shows that the use of computational fluid dynamics can realize the simulation analysis of a self-cleaning low-temperature plasma fume purification device, and the fume purification device has a strong fume purification ability.

The effect of relative humidity on the polarization Mueller matrix under the oil smoke environment

For the variation of the polarized Mueller matrix of oil smoke particles under different relative humidity levels, the polarized single scattering characteristics of oil smoke particles are studied by using the Mie scattering theory, and the multiple scattering simulation is implemented with the Monte Carlo method. Variation in relative humidity is achieved by changing in mixing of the oil smoke and the water fog particles during the same dry particle filling time. Using the 36 sets of polarized Mueller matrices method, the Mueller matrix patterns of oil smoke were calculated for four conditions of 0%, 10%, 40%, and 95% relative humidity, respectively. We can verify the simulation’s correctness from the simulation and the experimental results. Specifically, as the relative humidity increases, the size of the Mueller matrix pattern increases, and the patterns of m22, m33, and m44 related to the depolarization characteristic change significantly. Furthermore, the scattering depolarization coefficients of the Mueller matrix polar decomposition increase with the increasing relative humidity, with the ability of depolarization being continuously enhanced. This method determines differences in relative humidity using intuitive measurements of stabilized scattering patterns, which can present a theoretical basis for the impact of environmental variation on polarization detection.

High-efficiency carbon-coated steel wool filter for controlling cooking-induced oil smoke

Cooking oil smoke (COS) contains many harmful substances, such as particulate matter, formaldehyde, and phenyl esters. Currently, commercial COS treatment equipment is expensive and requires a large space. Furthermore, a large amount of agricultural waste is generated and is mainly burned onsite, producing large amounts of greenhouse gases and air pollutants. This waste could be reused as a precursor for biochar and activated carbon. Therefore, this research used saccharification and catalytic hydrothermal carbonization to process rice straw and produce compact carbon-based filters (steel wool-C) for removing cooking-induced pollutants. Scanning electron microscopy indicated that carbon layers were coated on the steel wool. The Brunauer-Emmett-Teller surface area of the carbon filter was 71.595 m2/g, 43 times larger than that of steel wool. The steel wool filter removed 28.9%–45.4% of submicron aerosol particles. Adding a negative air ionizer (NAI) to the filter system enhanced the particle removal efficiency by 10%–25%. The removal efficiency of total volatile organic compounds was 27.3%–37.1% with the steel wool filter, but 57.2%–74.2% with the carbon-containing steel wool filter, and the NAI improved the removal efficiency by approximately 1%–5%. The aldehyde removal efficiency of the carbon filter with NAI was 59.0%–72.0%. Conclusively, the compact steel wool-C and NAI device could be promising COS treatment equipment for households and small eateries.

Development of an antimicrobial fungal egg tray containing orange oil and smoke for eggs preservation at room temperature

The prevention and controlled growth of pathogenic bacteria on eggs during storage and distribution at room temperature is important to ensure commercial eggs and egg products are safe for consumer. This study investigated the combined effects of orange oil (0.001%-0.004% v/w) and smoke for 10 min in paper egg tray packaging produce from the fungal pulp of Trametes versicolor. Eggs were kept in the developed paper egg tray at room temperature (30 ± 2°C). The mechanism of the combined antibacterial effects againstEscherichia coli, Salmonella Typhimurium, and Staphylococcus aureus and egg quality were investigated. The combination of orange oil (0.004%) and smoke delayed all bacteria and suppressed changes in weight loss and the quality factor of eggs (Haugh unit, yolk index, albumen index) for at least 14 d. It was found that the volatile orange oil smoke in the egg tray could be passed through the structure of the cell wall and membrane of bacteria, giving rise to loss of cell viability by irreversibly damaging the cell membranes ofall the bacteria in this test. Moreover, higher antioxidant activity was found on the eggs than on the eggshells, which is linked to greater shelf-life of treated eggs. The study demonstrates an improved paper egg tray packaging system and the possibility of combining released essential oils and smoke, which can be extended to egg products. Smoke can also be modified on the surface ofpaper egg trayseasily, which shows potential in functionalizing implanted materials with antibacterial properties.

A Qualitative Investigation of Volatile Organic Components of Antimicrobial Oil Smoke Vapors

A petroleum middle distillate, known as fog oil (FO), has been used in the United military battlefield to create obscurant smoke screens. During studies on the feasibility of replacing FO with relatively environmentally benign natural oil esters, with similar flow properties, such as methyl soyate (MS), it was observed that FO and MS aerosols and vapors were lethal to Salmonella typhimurium strains (Ames strains used to test for mutagenic activity in the Modified Ames Assay) even after very short exposures. It was further shown that vapors produced from the vegetable oil esters under certain conditions exhibited antimicrobial activity against a wide range of Gram-positive and Gram-negative bacteria. In this study, we examined the antimicrobial properties of volatile organic compounds detected in vegetable oil ester vapors. The experiments involved introduction of a known amount of specific compounds present in oil smoke vaors, individually and in combination, into an exposure chamber containing nutrient agar petri dishes inoculated with Salmonella typhimurium. Petri dishes were removed from the chamber after varied exposure periods to determine survival of the bacteria. The results of the experiments showed that individual compounds exhibited antimicrobial activity but lower than the vapors produced during thermal aerosol generation process suggesting the antimicrobial activity of the vapors is likely a synergistic activity of multiple components of the vapors.

A novel method of identifying and analysing oil smoke plumes based on MODIS and CALIPSO satellite data

Abstract. Black carbon aerosols are the second largest contributor to global warming while also being linked to respiratory and cardiovascular disease. These particles are generally found in smoke plumes originating from biomass burning and fossil fuel combustion. They are also heavily concentrated in smoke plumes originating from oil fires, exhibiting the largest ratio of black carbon to organic carbon. In this study, we identified and analysed oil smoke plumes derived from 30 major industrial events within a 12-year timeframe. To our knowledge, this is the first study of its kind that utilized a synergetic approach based on satellite remote sensing techniques. Satellite data offer access to these events, which, as seen in this study, are mainly located in war-prone or hazardous areas. This study focuses on the use of MODIS (Moderate Resolution Imaging Spectroradiometer) and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) products regarding these types of aerosol while also highlighting their intrinsic limitations. By using data from both MODIS instruments on board Terra and Aqua satellites, we addressed the temporal evolution of the smoke plume while assessing lidar-specific properties and plume elevation using CALIPSO data. The analysis method in this study was developed to better differentiate between oil smoke aerosols and the local atmospheric scene. We present several aerosol properties in the form of plume-specific averaged values. We believe that MODIS values are a conservative estimation of plume aerosol optical depth (AOD) since MODIS algorithms rely on general aerosol models and various atmospheric conditions within the look-up tables, which do not reflect the highly absorbing nature of these smoke plumes. Based on this study we conclude that the MODIS land algorithms are not yet suited for retrieving aerosol properties for these types of smoke plumes due to the strong absorbing properties of these aerosols. CALIPSO retrievals rely heavily on the type of lidar solutions showing discrepancy between constrained and unconstrained retrievals. Smoke plumes identified within a larger aerosol layer were treated as unconstrained retrievals and resulted in conservative AOD estimates. Conversely, smoke plumes surrounded by clear air were identified as opaque aerosol layers and resulted in higher lidar ratios and AOD values. Measured lidar ratios and particulate depolarization ratios showed values similar to the upper ranges of biomass burning smoke. Results agree with studies that utilized ground-based retrievals, in particular for Ångström exponent (AE) and effective radius (Reff) values. MODIS and CALIPSO retrieval algorithms disagree on AOD ranges, for the most part, due to the extreme light-absorbing nature of these types of aerosols. We believe that these types of studies are a strong indicator for the need of improved aerosol models and retrieval algorithms.

Influencing factors of air volume in kitchen cooking exhaust shaft systems of high-rise residential buildings

This paper uses mathematical model theoretical calculation and experimental verification to study the pressure distribution inside the residential kitchen flue and the flow rate of each user through three aspects: temperature difference, opening rate and hood performance. Based on fluid network theory, the flow equation of oil smoke in the cooking exhaust shaft system is established. The accuracy of the mathematical model model was verified through experiments and applied to the calculation of the flue in the kitchen of a 30-story residential building in Shenyang. The results show that the static pressure decreases continuously with the increase of floor height, and the highest pressure appears at the lower level of the floor. The pressure keeps rising as the opening rate increases, i.e., the more users open, the higher the pressure at the bottom floor. Under the joint action of thermal pressure and flue resistance, the static pressure shows a low-high-low distribution form, with the temperature difference increases, the maximum static pressure in the flue moves to the bottom; the flow rate of users on each floor increases with the height, and decreases with the increasing rate of opening, under the influence of thermal pressure user flow distribution is high-low-high distribution.

Design and application of online derivatization device for polar organics on atmospheric particulate filter

设计制作了一套用于气相色谱-质谱(GC-MS)分析极性有机物的在线衍生装置,并将其应用于大气颗粒物样品中极性有机物的检测。将大气颗粒物滤膜样品置于GC-MS进样口,通过使用套针组件,匀速引入气态衍生试剂N-甲基-N-(三甲基硅烷)三氟乙酰胺(MSTFA),使其在衬管内于310 ℃下与待测物接触,10 min即可完成硅烷化在线反应。反应过程中,色谱柱箱保持低温,衍生产物得以在柱头保留,反应完成后色谱柱箱程序升温,使衍生产物直接进行后续分离检测。应用在线衍生装置建立有机酸分析方法,获得了一元酸、二元酸、芳香酸、醇等极性有机物的检测信息,涵盖了大气化学分析常见的大部分目标化合物。该方法检出限为0.02~0.53 mg/L,线性相关系数为0.976~0.996,日内、日间RSD为0.27%~7.28%,适用于批量大气环境样品检测。与传统离线衍生技术相比,本装置使衍生反应处于高温惰性气体氛围,排除空气中水分对衍生试剂的损耗和衍生产物降解风险,反应稳定、效率高;固体滤膜上有机物进行热解吸的同时完成在线衍生,样品需求量小,操作简单,零有机试剂污染,并有望应用于醇类、酚类等多种极性有机化合物的分析。此外, 该装置搭建简单,可模块化设计,适用于不同品牌气相色谱仪,具有商业化推广前景。

The Facts of Science & the Values of Social Justice

The Facts of Science & the Values of Social Justice

Feasibility of using bed filters packed with rice-straw-based activated carbon and selected biomass waste for the control of frying fume exhaust.

Open-air burning of rice straw (RS) on sites after harvesting produces tremendous amounts of air pollutants in Southeast Asia. Additionally, cooking oil smoke (COS) from high-temperature frying is classified as "Probably carcinogenic to humans" (Group 2A) by the International Agency for Research on Cancer. To mitigate the air pollution from COS, RS was recycled to prepare activated carbon (AC), which was used as a bed filter (BF) packing material for COS removal, and to our best knowledge, this study is the first one. Besides, a negative air ionizer (NAI) was firstly utilized to enhance the removal efficiency (η) of COS particles. Other biomass waste, including tea leaves (TL), wood dust (WD), rice hulls (RH), and coffee grounds (CG), were also used as packing materials for comparison. Specific surface area and pore volume of the packing materials were determined by nitrogen adsorption/desorption isothermal. Laser airborne particle counters and volatile organic compound (VOC) monitors (photoionization detector) were utilized for real-time recording of the particle and VOC concentration of COS. Economic assessments for the control of COS was also conducted. For submicron particles, the removal efficiency of the BFs ranged from 0 to 98% and the AC filter had the highest quality factor. The NAI remarkably enhanced the η value and filter quality factor. For the removal of particles larger than 2.5μm, all BFs had η > 96%. The removal efficiency of volatile organic compounds (VOCs) (ηVOC) of the test BFs ranged from 18.22 to 90.8%. The AC filter had the largest pore volume (0.432cm3/g) and surface area (877m2/g) among all packing materials, causing this filter to have the highest ηVOC and adsorption capacity (over 28.3mg-VOCs/g-AC). The annual operating costs of the TL, WD, RH, CG, and AC filters were 319.4, 23.3, 29.1, 189.4, and 62.9 US$, respectively. Therefore, using RS to prepare an AC bed filter for the removal of COS is a practical and sustainable strategy for COS control.

Is oil temperature a key factor influencing air pollutant emissions from Chinese cooking?

Cooking is an important source of air pollutants in Chinese residences. Cooking emissions are influenced by many factors, among which oil temperature is one of the most influential. In this study, 15 typical Chinese dishes, prepared using oil-based cooking methods (stir-, pan- and deep-frying), were chosen. The experiment was repeated three times with each dish—freshly prepared for each subsequent analysis—considering five key factors, to determine the emission rates of fine particulate matter (PM2.5), ultrafine particles (UFPs), formaldehyde, and total volatile organic compounds (TVOC). The oil temperature and oil consumption were measured. A partial correlation analysis was performed to identify the influence of oil temperature on air pollutant emission rates during Chinese residential cooking. The zero-order correlation coefficients for all air pollutants, excluding UFPs, and partial correlation coefficients for all air pollutants, were not significant, implying that the influence of oil temperature on air pollutant emission rates was not significant, because practical peak oil temperatures (112–177 °C) were mostly below the oil smoke point (107–234 °C).

The Irony of Fishermen Life in Bontang Islands, East Kalimantan, Indonesia

Bontang Bay, East Kalimantan is strategically located and rich in marine resources. However, people live at the islands of Gusung and Malahing are generally poor. This paper observes the socio-economic condition of fishermen at the two small islands and their relation with industries. The data collection techniques consist of physical observation, informal interview, and document review. The gathered data is analysed qualitatively. Fishermen at Gusung and Malahing are adversely affected by the impacts of climate change. In addition they are trapped by collectors (middle men) for financing operational cost of fishing and supporting their life during draught season. Their area are vulnerable of being impacted by industries’ activities such as oil spill, smoke stake and odor. It is required for industries located at the area to help alleviate fishermen poverty by initiating innovative CSR for creating self-reliance community.

Systemic contact dermatitis caused by inhaled cashew oil smoke

Systemic contact dermatitis caused by inhaled cashew oil smoke

Defining Method Research of Technological Conflict Based on Petri Net Theory

It is an difficult step using technological contradictions definition of Theory of Inventive Problem Resolving (TRIZ). A method for defining technological conflict based on analyzing of conflict relations in Theory of Petri Net was put forward. The technological conflicts were defined by constructing and analyzing Petri Net model of product. It is a technological support to resolve conflict using TRIZ. Such a series of methods and procedures had been used in the Technical-Conflict determination and solution of Ultraviolet Cooking Oil Smoke Purifier, with a better result obtained. It is proved the validity of Theory of Petri Net for product innovation design.

The Analysis of Effect on the Heat Conduction Oil Smoke Ingredients by Different Ignition Ways

This article analyzes the smoke ingredients of heat conduction oil by Gas Chromatography-Mass Spectrometer (GC-MS). Meanwhile, the effect on smoke dust ingredients by two different ignition ways of touching high-temperature surface and wick will be compared. Moreover, the different influences on the smoke by diverse extracts are studied as well. The result shows that n-hexane has better effect than aether. Heat conduction oil produces more polycyclic aromatic hydrocarbon (PAH) by the way of touching high-temperature surface and it produces more oxidizing materials by the other way. The research can provide a certain assistance for the analysis of the combustion of the heat conduction oil in fire physical evidence identification.

Comparison of different tracers for PIV measurements in EHD airflow

In this study, a proposed method for selecting a tracer for particle imaging velocimetry (PIV) measurement in electrohydrodynamics flows was developed. To begin with, several published studies were identified that exploit different tracers, such as oil smoke, cigarette smoke and titanium dioxide (TiO2). An assortment of tracers was then selected based on comparisons with conventional dimensionless numbers; Stokes number (St), Archimedes number (Ar) and electrical mobility ratio (M). Subsequently, an experimental study for testing tracers was developed, which enabled the velocity profile of an ionic wind generated by a needle/ring configuration to be measured. Air velocity measurements carried out with a Pitot tube, considered as the reference measurements, were compared to PIV measurements for each tracer. In addition, the current–voltage curves and the evolution of the current during seeding were measured. All the experimental results show that TiO2, SiO2 microballoons and incense smoke are the ideal tracers in the series of tracers investigated.

Antifouling property of highly oleophobic substrates for solar cell surfaces

Reduction of solar cell conversion efficiency by bird spoor or oil smoke is a common issue. Maintaining the surface of solar cells clean to retain the incident light is of utmost importance. In this respect, there has been growing interest in the area of superhydrophobicity for developing water repelling and self-cleaning surfaces. This effect is inspired by lotus leaves that have micro papillae covered with hydrophobic wax nanostructures. Superhydrophobic surfaces on transparent substrates have been developed for removing contaminants from solar cell surfaces. However, oil cannot be removed by superhydrophobic effect. In contrast, to prevent bird spoor, a highly oleophobic surface is required. In a previous study, we reported transparent-type fabrics comprising nanoparticles with a nano/micro hierarchical structure that ensured both oleophobicity and transparency. In the current study, we developed new highly oleophobic stripes that were constructed into semi-transparent oleophobic surfaces for solar cells. Solar cell performance was successfully maintained; the total transmittance was a key factor for determining conversion efficiency.

The Design and Research of the New Energy Efficient Combustion Stove

For overcoming flaws of traditional gas stove and kitchen ventilator, the structure and principle of internal combustion stove was proposed. While working, the mixture of oil smoke, water vapor, air and natural gas was completely mixed and burned in furnace chamber. The inner pressure of furnace chamber is higher than atmosphere. In the process of being emitted outdoor, the exhaust gas in high temperature heated the gas mixture into the furnace chamber. So theoretically, the internal combustion stove has these characters such as higher thermal efficiency, lower cost, easy maintenance, safety and environmental protection, and so on. The prototype was developed and the working principle of internal combustion Stove was verified. The flow state in the furnace chamber and the thermal of inlet pipe and exhaust pipe was analyzed based on ANSYS, GAMBIT and FLUENT. The verification test further confirmed the principle of internal combustion stove and was consistent with the experimental data, which has important reference value for the improvement and optimization in structure of internal combustion stove.

Intermediate Air Filters for General Ventilation Applications: An Experimental Evaluation of Various Filtration Efficiency Expressions

Neither the European standard nor the US standard for classification of intermediate class filters comprises testing of filter performance with respect to ultrafine particles (UFPs) or particles of the most penetrating size (MPPS). This could turn out to be a major lack in classification standards since UFPs have been pointed out as a serious health hazard. In this study, fractional efficiencies of eight new full-scale bag filters and twenty-three new filter medium samples were determined. The influence of air velocity and aerosol type was investigated, and correlations between efficiencies for UFPs (EFUFPs), MPPS-sized particles (EFMPPS) and 0.4 μm-sized particles (EF0.4μm) were established. The tested bag filters were challenged by four aerosol types: a neutralized atomized oil aerosol, the same oil aerosol but non-neutralized, a non-neutralized thermally generated oil smoke, and a “natural” indoor aerosol. The tests were carried out at different air velocities through the filter medium, ranging between 0.08 m/s and 0.22 m/s. The relationships that were observed between EFUFPs, EFMPPS, and EF0.4μm appeared to be linear within the observed filtration efficiency ranges. These relationships were similar regardless of the test aerosol type used, but somewhat different for glass fiber filters than for charged synthetic filters. Generally, EFMPPS was 10–20% lower than EF0.4μm. The influence of air velocity variations on the size resolved efficiency was determined. The glass fiber filters showed practically the same fractional efficiencies regardless of whether the test aerosol was neutralized or not. However, the charged synthetic filters showed substantially lower efficiencies when tested with the non-neutralized aerosol compared to the case when the aerosol was neutralized.

Black and brown carbon fractal aggregates from combustion of two fuels widely used in Asian rituals

Incense sticks and mustard oil are the two most popular combustion fuels during rituals and social ceremonies in Asian countries. Given their widespread use in both closed and open burning activities, it is important to quantify the spectral radiative properties of aerosols emitted from the combustion of both fuels. This information is needed by climate models to assess the impact of these aerosols on radiative forcing. In this study, we used a 3-wavelength integrated photoacoustic-nephelometer – operating simultaneously at 405, 532 and 781nm – to measure the optical coefficients of aerosols emitted from the laboratory combustion of mustard oil lamp and two types of incense sticks. From the measured optical coefficients at three wavelengths, time-varying single scattering albedo (SSA), absorption Ångström exponent (AAE), and scattering Ångström exponent (SAE) were calculated. For incense smoke particles, the time-averaged mean AAE values were found to be as high as 8.32 (between 405 and 532nm) and 6.48 (between 532 and 781nm). This spectrally-varying characteristic of AAE indicates that brown carbon – a class of organic carbon which strongly absorbs solar radiation in the blue and near ultraviolet – is the primary component of incense smoke aerosols. For aerosols emitted from the burning of mustard oil lamp, the time-averaged mean AAE values were ∼1.3 (between 405 and 781nm) indicating that black carbon (BC) is the primary constituent. Scanning electron microscopy combined with image processing revealed the morphology of incense smoke aerosols to be non-coalescing and weakly-bound aggregates with a mean two-dimensional (2-d) fractal dimension (Df)=1.9±0.07, while the mustard oil smoke aerosols had typical fractal-like BC aggregate morphology with a mean 2-d Df=1.85±0.09.