Total Reduced Sulfur Compounds Research Articles

Principal component analysis of summertime ground site measurements in the Athabasca oil sands with a focus on analytically unresolved intermediate-volatility organic compounds

Abstract. In this paper, measurements of air pollutants made at a ground site near Fort McKay in the Athabasca oil sands region as part of a multi-platform campaign in the summer of 2013 are presented. The observations included measurements of selected volatile organic compounds (VOCs) by a gas chromatograph–ion trap mass spectrometer (GC-ITMS). This instrument observed a large, analytically unresolved hydrocarbon peak (with a retention index between 1100 and 1700) associated with intermediate-volatility organic compounds (IVOCs). However, the activities or processes that contribute to the release of these IVOCs in the oil sands region remain unclear. Principal component analysis (PCA) with varimax rotation was applied to elucidate major source types impacting the sampling site in the summer of 2013. The analysis included 28 variables, including concentrations of total odd nitrogen (NOy), carbon dioxide (CO2), methane (CH4), ammonia (NH3), carbon monoxide (CO), sulfur dioxide (SO2), total reduced-sulfur compounds (TRSs), speciated monoterpenes (including α- and β-pinene and limonene), particle volume calculated from measured size distributions of particles less than 10 and 1 µm in diameter (PM10−1 and PM1), particle-surface-bound polycyclic aromatic hydrocarbons (pPAHs), and aerosol mass spectrometer composition measurements, including refractory black carbon (rBC) and organic aerosol components. The PCA was complemented by bivariate polar plots showing the joint wind speed and direction dependence of air pollutant concentrations to illustrate the spatial distribution of sources in the area. Using the 95 % cumulative percentage of variance criterion, 10 components were identified and categorized by source type. These included emissions by wet tailing ponds, vegetation, open pit mining operations, upgrader facilities, and surface dust. Three components correlated with IVOCs, with the largest associated with surface mining and likely caused by the unearthing and processing of raw bitumen.

Alternate approaches for assessing impacts of oil sands development on air quality: A case study using the First Nation Community of Fort McKay

ABSTRACTPrevious analyses of continuously measured compounds in Fort McKay, an indigenous community in the Athabasca Oil Sands, have detected increasing concentrations of nitrogen dioxide (NO2) and total hydrocarbons (THC), but not of sulfur dioxide (SO2), ozone (O3), total reduced sulfur compounds (TRS), or particulate matter (aerodynamic diameter <2.5 μm; PM2.5). Yet the community frequently experiences odors, dust, and reduced air quality. The authors used Fort McKay’s continuously monitored air quality data (1998–2014) as a case study to assess techniques for air quality analysis that make no assumptions regarding type of change. Linear trend analysis detected increasing concentrations of higher percentiles of NO2, nitric oxide (NO), and nitrogen oxides (NOx), and THC. However, comparisons of all compounds between an early industrial expansion period (1998–2001) and current day (2011–2014) show that concentrations of NO2, SO2, THC, TRS, and PM2.5 have significantly increased, whereas concentrations of O3 are significantly lower. An assessment of the frequency and duration of periods when concentrations of each compound were above a variety of thresholds indicated that the frequency of air quality events is increasing for NO2 and THC. Assessment of change over time with odds ratios of the 25th, 50th, 75th, and 90th percentile concentrations for each compound compared with an estimate of natural background variability showed that concentrations of TRS, SO2, and THC are dynamic, higher than background, and changes are nonlinear and nonmonotonic. An assessment of concentrations as a function of wind direction showed a clear and generally increasing influence of industry on air quality. This work shows that evaluating air quality without assumptions of linearity reveals dynamic changes in air quality in Fort McKay, and that it is increasingly being affected by oil sands operations.Implications: Understanding the nature and types of air quality changes occurring in a community or region is essential for the development of appropriate air quality management policies. Time-series trending of air quality data is a common tool for assessing air quality changes and is often used to assess the effectiveness of current emission management programs. The use of this tool, in the context of oil sands development, has significant limitations, and alternate air quality change analysis approaches need to be applied to ensure that the impact of this development on air quality is fully understood so that appropriate emission management actions can be taken.

Characterization of a hyperthermophilic sulphur-oxidizing biofilm produced by archaea isolated from a hot spring

Normal 0 21 false false false ES-TRAD X-NONE X-NONE Background: Sulphur-oxidizing microorganisms are widely used in the biofiltration of total reduced sulphur compounds (odorous and neurotoxic) produced by industries which include high temperature process steps, such as the cellulose and petrochemical industries. Some hyperthermophilic microorganisms have the capability to oxidize these compounds at high temperatures (>60oC), and archaea of this group, e.g. Sulfolobus metallicus , are commonly used in biofiltration technology. Results: In this study, a hyperthermophilic sulphur-oxidizing strain of archaea was isolated from a hot spring (Chillan, Chile) and it was called M1. It was identified archaea of the genus Sulfolobus (99% homology with Sulfolobus solfataricus 16S rDNA). Biofilms of this culture grown on polyethylene rings showed an elemental sulphur oxidation rate of 95.15 ± 15.39 mg S l -1 d -1 , higher than the rate exhibited by the biofilm of the sulphur-oxidizing archaea Sulfolobus metallicus (56.8 ± 10.91 mg l -1 d -1 ) Conclusions: The results suggest that the culture M1 is useful for biofiltration of total reduced sulphur gases at high temperatures, as well as other biotechnological applications. /* Style Definitions */ table.MsoNormalTable {mso-style-name:Tabla normal; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:Times New Roman,serif; mso-ansi-language:ES-TRAD; mso-fareast-language:ES-TRAD;}

Atmospheric Dispersion Study of TRS Compounds Emitted from a Pulp Mill Plant in Coastal Regions of the Uruguay River, South America

ABSTRACTThe atmospheric dispersion of total reduced sulfur (TRS) emissions from the pulp mill plant of Fray Bentos, Uruguay is simulated. The local authorities of the Environmental Monitoring Program (EMP) of Gualeguaychu, Argentina, received social complaints of malodor presence in different places of the region. An atmospheric dispersion model coupled to a boundary layer forecast model is used to simulate 11 events in which the EMP officials attended the scene in order to verify the situation. The validation of modeled winds with the observations from a meteorological tower indicates reasonably accurate wind forecasts. The spatial layout of the modeled TRS plumes is compared with the geographical distribution of points in the area where the social complaints were recorded. Nine of the 11 studied events are successful modeling cases since a positive (negative) in situ verification matches with a plume position over (far from) the site. In one of the two unsuccessful modeling cases, although the plume is marginally distant from the site, the average wind direction error is the largest one of all the events. In the other case the modeled plume is in fact over the site, but the situation was negatively verified. The reason for the disagreement could be the wind direction changes during the event. This was the longest modeled case that lasted for 7 hours and the plume was meandering during that time; first from SSW to the S, then back the SSW, and finally to the S and SSE. The conclusion of the study is that, despite the inherent uncertainty of numerical simulations, the implemented modeling system shows versatility and proves to be a useful tool not only for diagnostic studies but also for preventing conflictive situations since it can produce reasonably accurate forecast of plume position and its potential impact.

Total reduced sulphur as a potential indicator of slaughterhouse hygiene

Measurements of total reduced sulphur (TRS) compounds, emitted from faeces, may be an indicator of hygiene in slaughterhouses. The aim of this study was to measure the concentrations of TRS compounds in the air at various locations and times in pig and cattle slaughterhouses. The data was then reviewed to see if there was any pattern associated with location in the slaughterhouses or any changes associated with activities or events. TRS concentration was lowest in chillers that are away from the slaughter area. Gut bursts generally led to increases in TRS but the level of increase was variable. In one slaughterhouse, ventilation fans were used during part of the day and this corresponded with falls in the TRS concentration. These variations in TRS concentration negate its use as a reliable indicator of slaughterhouse hygiene.

Pilot-scale study on ozone-enhanced catalytic oxidation of waste gas emissions from the pulp and paper industry

Field studies were conducted at Domtar's Kraft pulp and paper mill (Hawesville, KY) for 2 weeks to investigate the treatment of high volume, low concentration (HVLC) waste gas streams using ozone-enhanced catalytic oxidation technology. The contaminants in the HVLC waste gas from the pulping area of the mill contained mainly methanol (360 ± 80 ppm) and total reduced sulfur compounds [dimethyl sulfide (DMS) (4400 ± 670 ppm) and dimethyl disulfide (150 ± 25 ppm). The catalysts used in the field studies included ViO2/TiO2 and CuO/MoO3/a-Al2O3. The results of the field study showed ozone-to-sulfur ratios >2, space velocities 90% destruction of DMS in the HVLC waste gas stream. Ozone-enhanced catalytic oxidation has key environmental advantages over incineration, including mild operating temperatures and thus, lower energy costs and lower NOx formation. Although the technology appeared to be feasible at the laboratory scale, the field study data revealed that several obstacles must be overcome prior to this technology being implemented at large scale. © 2010 American Institute of Chemical Engineers Environ Prog, 2011

Oxidation of methanol and total reduced sulfur compounds with ozone over V 2O 5/TiO 2 catalyst: Effect of humidity

The purpose of this study was to investigate the feasibility of using ozone-enhanced catalytic oxidation for the treatment of high volume, low concentration (HVLC) waste gas streams at a Kraft pulp and paper mill that contain hazardous air pollutants such as methanol (CH 3OH), reduced sulfur compounds (TRS), including dimethyl sulfide (DMS), dimethyl disulfide (DMDS), methanethiol (MT), hydrogen sulfide (H 2S), and saturated with moisture. This paper reports that ozone-enhance V 2O 5-TiO 2 catalyzed oxidation is a stable and effective process to remove methanol and TRS compounds in the presence of moisture that has composition similar to the effluent stream coming out of a pulp mill blow tank. The effect of moisture on the oxidation of CH 3OH, MT and DMS was studied using V 2O 5/TiO 2 as a catalyst at different feed compositions (C methanol: 1000 and 7500 ppm; C DMS: 250 and 1000 ppm; and C MT: 250 and 1000 ppm) and gas hourly space velocities (37,000–150,000 h −1) at 250 °C and O 3-to-substrate mole ratio of 2.1. Conversions of methanol and TRS compounds were high and the main products were CO 2, CO and SO 2 with small amounts of partial oxidation products. Increasing the relative humidity of the gas stream from zero to 18,000 ppm reduced the conversion of methanol, whereas the conversion of TRS compounds was not affected, although the selectivity for partial oxidation products of TRS compounds decreased. High moisture levels have inhibition effect on the reactions because of competitive adsorption of methanol and water on to the same sites. The increase in the complete oxidation of TRS products could be due to forming hydroxyl ion radicals in presence of ozone and water molecules. Possible reaction mechanisms have been proposed for the complete oxidation of methanol and TRS compounds with ozone based on the product distribution.

The Role of Catalyst Properties on Methanol Oxidation over V2O5–TiO2 Using Ozone

Oxidation of methanol over V2O5 catalysts supported on anatase TiO2 that were prepared using sol-gel formation and impregnation procedures were investigated. The effects of incorporating Mg in sol-gel to influence the properties of the catalyst were also studied. The process provides an alternative low temperature reaction pathway for reducing emissions of hazardous air pollutant (HAPs) such as methanol and total reduced sulfur compounds (TRS) from pulp and paper mills. The bulk and surface composition of the catalysts were determined by XRD and SEM-EDAX, respectively. The X-ray diffraction patterns of the vanadia–titania catalysts showed mainly the anatase phase of TiO2. Temperature programmed desorption of methanol from the different catalyst showed that the α and β peaks differ significantly with V content and addition of Mg. The combination of gas phase and surface reactions on the V/TiO2 catalysts reduced the amount of ozone required for high degradation of methanol to mainly COx with small quantities of methyl formate. In the absence of ozone the catalysts showed very low activity. It is hypothesized that the ozone is directly influencing the V4+ and V5+ redox cycle of the catalyst. Oxidation of methanol is influenced by the operation variables and catalyst properties. The results of this study revealed that the V content has significant influence on the catalyst activity, and the optimum vanadia loading of about 6 wt%. Higher turnover frequencies were observed over sol-gel catalysts than with catalysts prepared by the impregnation method.

Dual Process Odor and Corrosion Control Treatment Train to Remove Total Reduced Sulfur Compounds

Dual Process Odor and Corrosion Control Treatment Train to Remove Total Reduced Sulfur Compounds Author(s)James RickerJoseph UglevichMichel PicknellSourceProceedings of the Water Environment FederationSubjectSession 60: Odor and Corrosion Control in Collection Systems: From the Pipes to the PlantDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2007ISSN1938-6478SICI1938-6478(20070101)2007:14L.4689;1-DOI10.2175/193864707787974670Volume / Issue2007 / 14Content sourceWEFTECFirst / last page(s)4689 - 4692Copyright2007Word count15

Caracterização de compostos reduzidos de enxofre gerados na produção de celulose kraft e pré-hidrólise kraft.

Um problema ambiental da indústria de celulose kraft é o odor causado pela emissão dos compostos reduzidos de enxofre gerados pela deslignificação de madeiras de um modo em geral. Para monitorar essas emissões, existem equipamentos simples, desenvolvidos para a medição contínua do "total reduced sulphur" (TRS), tal como o analisador coulométrico. Neste trabalho, foram analisados sulfeto de hidrogênio (H2S), metil mercaptana (CH3SH), dimetil sulfeto [(CH3)2S)] e dimetil dissulfeto [(CH3)2S2], gerados em deslignificações laboratoriais kraft e pré-hidrólise kraft de dois grupos de madeiras de folhosas. Um dos grupos de madeiras continha 25% e o outro 20% de lignina, base peso seco. Foi observado que as madeiras com menores teores de lignina geraram significativamente menores quantidades de compostos reduzidos de enxofre de TRS. Não foram notadas diferenças significativas nas quantidades totais geradas entre os processos de deslignificação estudados. O processo pré-hidrólise kraft foi mais sensível aos teores de lignina da madeira que o processo kraft. Recomenda-se, por isso, trabalhar com madeiras com menores teores de lignina quando do uso do processo pré-hidrólise kraft para produção de celulose. As principais formas geradas de TRS foram dimetil sulfeto e metil mercaptana.

Thiosulphate oxidation by Thiobacillus thioparus and Halothiobacillus neapolitanus strains isolated from the petrochemical industry

Sulphur Oxidizing Bacteria (SOB) is a group of microorganisms widely used for the biofiltration of Total Reduced Sulphur compounds (TRS). TRS are bad smelling compounds with neurotoxic activity which are produced by different industries (cellulose, petrochemical). Thiobacillus thioparus has the capability to oxidize organic TRS, and strains of this bacterium are commonly used for TRS biofiltration technology. In this study, two thiosulphate oxidizing strains were isolated from a petrochemical plant (ENAP BioBio, Chile). They were subjected to molecular analysis by real time PCR using specific primers for T. thioparus . rDNA16S were sequenced using universal primers and their corresponding thiosulphate activities were compared with the reference strain T. thioparus ATCC 10801 in batch standard conditions. Real time PCR and 16S rDNA sequencing showed that one of the isolated strains belonged to the Thiobacillus branch. This strain degrades thiosulphate with a similar activity profile to that shown by the ATCC 10801 strain, but with less growth, making it useful in biofiltration.

Vapour-liquid partition of volatile organic compounds in kraft black liquors

The vapour-liquid partition of various VOC (Volatile Organic Compounds) in a number of industrial black liquors was investigated. The information can be used to determine the distribution of VOC in different condensate and gas streams in a kraft mill. Batchwise evaporation of weak black liquors was performed on a lab scale. The evaporation was carried out at atmospheric pressure up to over 90% dry solids content. During evaporation, condensate samples were collected and analysed with respect to 15 compounds, total organic carbon (TOC), chemical oxygen demand (COD) and pH. The study resulted in concentration profiles of various VOC in the vapour (condensate) during evaporation. An increase in concentrations of total reduced sulphur compounds (TRS), ammonia, methanol and guaiacol at high dry solids content indicated a chemical degradation of the liquor. The condensates with the lowest TOC and COD levels were obtained for a dry solid content of 30-40 wt-% regardless of the original dry solids content in the black liquor. (Less)

The South Karelia Air Pollution Study: changes in respiratory health in relation to emission reduction of malodorous sulfur compounds from pulp mills.

The authors assessed the health effects of emission reduction of malodorous sulfur compounds in a prospective cohort study with a controlled natural experiment. A total of 810 subjects (83%) participated in the follow up: 316 from the severely polluted, 306 from the moderately polluted, and 188 from the nonpolluted communities. In the severely polluted community, the annual ambient air concentration of total reduced sulfur compounds decreased from 11 microg/m3 to 6 microg/m3. Compared with the nonpolluted community, the relative decrease in acute respiratory infections, adjusted for a change in smoking habits, was 0.53 episodes/person-year (95% confidence interval = 0.22, 0.83) in the severely polluted community and 0.36 episodes/person-year (95% confidence interval = 0.06, 0.66) in the moderately polluted community. In addition, the frequency of nasal symptoms (p = .004) and cough (p = .037) decreased significantly. The results are consistent with the hypothesis that exposure to malodorous sulfur compounds increases the risk of acute respiratory infections and symptoms of the respiratory tract.

Measurement of total reduced sulfur compounds in ambient air

Methods for the determination of total reduced sulfur (TRS) compounds in the ambient air based on coulometric detection (Philips Model PW 9700 analyzer) and thermal oxidation followed by detection using pulsed fluorescence (Teco Model 43 analyzer) have been evaluated. Analytical response factors, relative to H/sub 2/S, were determined for both the individual TRS compounds and compounds such as terpenes and carbonyl sulfide that may be a potential source of interference. The results for COS and terpenes indicate that in a typical monitoring situation normally encountered concentrations of these compounds are not expected to cause significant measurement bias. The results for the individual TRS compounds indicate that while variations in TRS composition are not a factor in assessing measurement bias for the thermal oxidation/pulsed fluorescence method, they are a factor for the Philips coulometric method; i.e., increasing positive measurement bias maybe introduced as the TRS composition shifts toward relatively less H/sub 2/S. Philips-Teco comparison data collected at a single site in the vicinity of three operating kraft pupil mills are compatible with these expectations. 8 references, 1 figure, 3 tables.

Marine Thiobacilli. I. Isolation and distribution.

Bacterial colonies were isolated from Caribbean and Atlantic Ocean seawaters by the membrane filter technique and enrichment cultures in which thiosulfate was the only added source of energy. Although colonies were never abundant (0–275 per 100 ml), they have been recovered from the open ocean. The colonies were translucent to pale yellow on thiosulfate marine agar. The cells were Gram-negative motile rods (1–3 μ in length) requiring seawater for growth. The pH of the culture flasks dropped to 2.1 – 2.3 in some cases, and to 5.6 in others. On the basis of these observations, the colonies have been classified as marine thiobacilli.In seawater samples examined, the total reduced sulfur compounds ranged from 0 to 0.101 milliequivalents per liter.