MODELING AND MEASUREMENT OF PARTICULATE MATTER (PM) COLLECTION FROM BOILER EXHAUST GAS IN ELECTROSTATIC WATER SPRAYING SCRUBBER

Boiler exhaust gas consists of many components that cause air pollution, such as: particulate matter (PM), SOx, NOx, COx, etc. These pollutants normally are mixed. To eliminate them, an electrostatic water spraying scrubber is used, depending on a coal fuel used for combustion source in the furnace. For PM, new guidelines will be changed from the existing 10 to 2.5 microns within the next few years. The scrubber is widely used for the collection of PM from industrial exhausts because of its low equipment and maintenance costs combined with operational safety and high collection efficiency. This study presents computed and experimented results of PM collection efficiency in an electrostatic water spraying scrubber. In this scrubber electric attraction between charged PM and charged water droplet improves PM collection considerably over conventional scrubber. Computed model takes into account initial liquid momentum, hydrodynamic and electric forces. The effects of operating parameters, such as gas velocity, applied voltage, charge to-mass ratio on PM collection efficiency within the scrubber, were also investigated. Computed results are in good agreement with the experimental data obtained in the laboratory. Compared to inertial scrubbers, the electrostatic water spraying scrubbers can operate at lower flow rate, but total collection efficiency is over 98% of all PM sizes.

Potential Use of Industrial Cocoa Waste in Biofuel Production

Worldwide, the wastes derived from food production are generated in elevated volumes annually. In particular, the cocoa industrial wastes represent a source of usable biomass for the elaboration of new products such as food, livestock feed, cosmetics, and chemical products, and they can even be used for the generation of biofuels. The cocoa industrial wastes include cocoa pod husk, mucilage, and bean shells, which contain compounds of interest for different industries. However, the lignocellulose content of these by-products requires a pretreatment to fully utilize them; thus, different biofuels can be produced, depending on the conversion technology used to obtain the highest biomass yield. Recent studies reported the use of cocoa industrial wastes for the production of solid, liquid, and gaseous biofuels; nevertheless, the most common use reported is as a direct combustion source, which is used to supply the same production plants. Therefore, the objective of this work is to carry out a review on the uses of the by-products generated from cocoa for the generation of biofuels, as well as the technological concept applied for the transformation. In addition, the future trends indicate the relevance of using catalysts in production to increase reactions in the conversion of compounds, including the use of statistical models to optimize the processing variables.

Systemic Lexicosemantic Connections of the Adjective Rich in English

The purpose of this article is to describe the meaning of the adjective rich and its systemic connections in the linguocultural aspect. Tasks: 1) determine the lexicosemantic variants of the adjective rich; 2) identify its synonyms and antonyms; 3) compare the semes of the adjective rich presented in different dictionaries. The relevance of this paper lies in the fact that the English linguistic worldview includes a certain area associated with linguocultural ideas about wealth that is represented by the adjective rich and its synonyms and antonyms. The scientific novelty of the article lies in the fact that for the first time the semes of the adjective rich are considered in terms of linguistic worldview and the theory of mentality. The research material was selected from modern authoritative English dictionaries. The main methods used here are the method of component analysis of vocabulary definitions, descriptive method using interpretation and generalization techniques, comparative method, and elements of the linguocultural method. The analysis showed that the adjective rich in the English language has 34 semes, which can be combined into 8 thematic groups: 1) person: ‘someone/person/people’, ‘endowed’, ‘have’, ‘possessions’, ‘contain’; ‘entertainment’, ‘(highly) amusing’, ‘(highly) developed’; 2) material wealth: ‘(a lot of) money/material wealth/property’, ‘(financially) profitable’, ‘remunerative’, ‘valuable/high value’; 3) abundance: ‘lush/abounding/abundant’, ‘a high standard of living’, ‘supplied’; 4) perception: ‘colour’, smell/fragrance’, ‘sound/tone’, ‘taste’; 5) something material: ‘(natural) substance’, ‘food (with fat/oil/eggs/sugar)’, ‘plant/nutrients’; 6) resources: ‘combustion’, ‘source’; 7) evaluation: ‘attractive/magnificently impressive/pleasant’, ‘beautiful’, ‘good’, ‘(highly) productive’, ‘(highly) varied’, ‘useful’; 8) quality: ‘complex’, ‘pure/nearly pure’, ‘percentage’, ‘quality’. In addition, 26 synonyms and 4 antonyms of the adjective rich were identified.

ECO-DESIGN: IMPACTS OF BLEACHING CHEMICALS AND VARNISHES ON THE AMOUNT OF CARBON DIOXIDE IN THE COMBUSTION OF ORIENTAL BEECH (FAGUS ORIENTALIS LIPSKY)

This study was carried out to determine the effects of bleaching chemicals and varnishes on the amount of carbon dioxide (CO2) in the combustion of oriental beech (Fagus orientalis Lipsky). For this purpose, samples of Oriental beech prepared according to ASTM D 358 contain 18% R1 = (NaOH + H2O2), R2 = (NaOH + Ca(OH)2 + H2O2), R3 = (Na2S2O5 + H2C2O4), R4 = (NaSiO3 + H2O2), R5 = (KMnO4 + Na2S2O5 + H2O2) solution groups, after bleaching with solution groups, water based, synthetic, polyurethane and acrylic varnish were applied according to ASTM D 3023 and combustion tests were carried out in accordance with ASTM E 160-50. Gas measurements were made with the SIGMA 74172 NSU flue gas device during the combustion process. As a result, in respect to the burning types; the highest amount of CO2 (ppm) was found in the self-combustion (8.468 ppm) while the lowest was obtained from the flame combustion source (4.599 ppm). In respect to the types of bleaching; the highest in R5 (7.458 ppm) and the lowest in R3 (4.059 ppm) were found. According to the varnish types; the highest value was found in the synthetic varnish (8.261), and the lowest value was found in the acrylic varnish (4.772 ppm). According to combustion type + bleaching solution + varnish type interaction, the highest values were found for without flame combustion (II) + R3 + Sn (18.40 ppm) and lowest for flame source combustion (I) + R5 + Pu (0.600 ppm). Consequently, the highest values for combustion gases were found in samples of oriental beech wood samples treated with water-based varnish with R1 solution. According to this, in terms of human health and life safety, possibility of fire in places, R3 solution and acrylic varnish may be used in the related industries.

The Changes of PM2.5, BC, Elements and Pollution Sources Using Nuclear Technology in Xinzhen, Beijing Over the Past Decade

The concentrations of PM2.5, black carbon (BC), elements as well as sources of pollution in Beijing from 2003 to 2018 were investigated. The results show that the concentrations of PM2.5 and BC had similar annual and seasonal trends, especially in autumn-winter, which with declining trends in recent years. The proportion of BC in PM2.5 reduced from 13% in 2013(max) to 8.5% in 2018(min), indicating the reducing measure of replacing coal boiler with gas boilers worked well. In this study, annual trends of 15 elements were also discussed, it is found that the concentrations of S, K, Mn, Ca, Pb, Cu, Mn and Fe displayed remarkable decrease these years. Br, Zn and Cl was growing overall and Cl was more concentrated in PM2.5 in autumn and winter. Moreover, the In detected by NAA with high sensitivity may be a new and crucial fingerprint element associated with coal combustion, industry emission or biomass combustion because of correlation with BC, Na, K, Cu and halogen elements well. Finally, 6-factor solution was identified during 2007 and 2016-2017 by EPA PMF, and the proportions of some pollution sources changed a lot in PM2.5. Soil management in north China reduced the soil and dust source by 9.2%; The contribution of Industry-S or secondary S showed decrease from 27.5% to 22.5% due to industries relocating , gasoline with sulfur optimization and coal burning restriction; Banning straw burning and waste incineration in 2007 kept biomass and waste combustion out gradually. However, initial stage of some policies maybe the main reasons for a small increase of coal combustion source despite some steps taken.

Centennial Records of PAHs and Black Carbon in Altay Mountain Peatlands, Xinjiang, China

Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are often used to indicate anthropogenic impacts on natural environmental changes during the past century. In this study, a 30 cm peat core was collected from the Jiadengyu (JDY) peatland in Altay Mountain and dated by the 137Cs and 210Pb methods. The total organic carbon, BC and PAHs contents in JDY peat core were 17.09-47.16%, 1.14-67.14 mg g-1 and 260.58-950.98 ng·g-1, respectively. The δ13CBC ranged from -31.5‰ to -27.43‰, with an average of -30.52‰. Scanning electron microscope (SEM) showed that the BC particles in the peat were lumpy or irregular in shape and retained the structure of plant fiber. The PAHs ratios, δ13CBC and the SEM result indicated the dominant biomass combustion source of BC in the peatland. The BC content increased from 1950 to 1980 and decreased after 1980. The change of BC and δ13CBC is different from the national BC emission pattern, probably reflecting the impact of local agricultural exploration and thus crop burning increase.

Occurrence of Polycyclic Aromatic Hydrocarbons (PAHs) in electric grilled foods commonly consumed in Port Harcourt, Nigeria: Distribution and contamination profiles

United State Environmental Protection Agency (USEPA) priority polycyclic aromatic hydrocarbons (PAHs) were investigated in electric grilled (EG) foods: plantain (EG-PN), meat (EG-MT), yam (EG-YM) and fish (EG-FH), commonly consumed in Port Harcourt, Rivers State, southern Nigeria. Distribution and concentrations of PAHs in the EG food samples were obtained by gas chromatography (GC) nalyses, after extraction using hexane/dichloromethane (1:3 v/v) and clean up by column chromatography. GC analyses identified 13 to 16 PAHs in the food samples with 10 observed to occur in all. Fluoranthene, pyrene (4-ring PAHs) and benzo(a)pyrene (5-ring PAH) were the most abundant, while the 2- and 3-ring PAHs were generally minor constituents or absent. Concentrations of PAHs in the EG foods ranged from 15.73 to 67.13 µg/kg and was observed to decrease in the order EG-PN>EG-MT > EG-YM > EG-FH with increase in grilling time. Ratios used as diagnostic indices of PAH formation processes indicate a combustion source for PAHs in the food samples and revealed electric grilling generated PAHs which contaminated the foods. Benzo(a)pyrene (BaP), used as a marker for PAH contamination in foods, had concentrations of 7.51 μg/kg, 2.68 μg/kg, 2.33 μg/kg and 1.85 μg/kg in EG-PN, EG-MT, EG-YM and EG-FH respectively. These values were above the maximum limit of 2 μg/kg set by the European Union, except for EG-FH which was slightly lower. Keywords: Food, Polycyclic aromatic hydrocarbons, Electric grill, Concentration, Diagnostic ratio, Nigeria.

Brown Carbon Sources in Singapore Identified by Factor Analysis of Atmospheric Pressure Chemical Ionization Mass Spectra

<p>Brown carbon (BrC) is an important candidate for the direct radiative effects of aerosol particles. It has been demonstrated that positive matrix factorization (PMF) is useful in analyzing Aerosol Mass Spectrometer (AMS) data for BrC source apportionment. However, fragmentation of molecular ions in AMS has been limiting its capability to categorize BrC sources. Soft-ionization mass spectrometric techniques are known to retain molecular information of chemical species. In this study, we applied atmospheric pressure chemical ionization mass spectrometry (APCI-MS) to identify the sources of water-soluble BrC. PM2.5 filter samples were collected at a site in Singapore during March-May of 2019. The extracted water-soluble organic matter (WSOM) was analyzed using APCI-MS, time-of-flight aerosol chemical speciation monitor (ToF-ACSM) and ultraviolet-visible spectrophotometer (UV-Vis). Five factor components were obtained by PMF analysis of the APCI-MS data. The PMF output and UV-Vis data were subsequently used to estimate the absorption Ångstrom exponents (AAE) of WSOM in each component. The estimated values of AAE ranged from 3.95 to 8.71. When comparing the factor contributions with simultaneously monitored gas and aerosol data, we found that the factor with the lowest value of AAE was likely emitted from a methane-rich combustion source, located east of the observation site. </p>

Characterization and Source Identification of Elements and Water-Soluble Ions in Submicrometre Aerosols in Brno and Šlapanice (Czech Republic)

Submicrometre aerosol particles (particulate matter, PM1) were collected in two Czech cities (Brno and Šlapanice) during week campaigns in winter and summer of 2009 and 2010. The aerosols were analysed for 14 elements and 12 water-soluble ions using inductively coupled plasma–mass spectrometry and ion chromatography techniques. The average PM1 mass concentration was 14.4 and 20.4 µg m−3 in Brno and Šlapanice, respectively. Most of the analysed elements and ions exhibit distinct seasonal variability with higher concentrations in winter in comparison to summer. The determined elements and ions together accounted for about 29% of total PM1 mass, ranging between 16% and 44%. Ion species were the most abundant components in collected aerosols, accounting for 27.2% of mass of PM1 aerosols, and elements accounted for 1.8% of mass of PM1 aerosols. One-day backward trajectories were calculated using the Hysplit model to analyse air masses transported towards the sampling sites. The Pearson correlation coefficients between individual PM1 components and PM1 mass and air temperature were calculated. To identify the main aerosol sources, factor analysis was applied. Six factors were identified for each locality. The following sources of PM1 particles were identified in Brno: a municipal incinerator, vehicle exhausts, secondary sulphate, a cement factory, industry and biomass burning. The identified sources in Šlapanice were as follows: a combustion source, coal combustion, a cement factory, a municipal incinerator, vehicle exhausts and industry.