Obchody 100. rocznicy śmierci Karola Stanisława Olszewskiego (1846–1915)

Propane-fueled forklifts are one source of carbon monoxide (CO) contamination of workplace air. The previous study carried out by the Quebec Occupational Health and Safety Research Institute dealt with worker exposure to CO during forklift use in buildings. It recommends that exhaust gas emissions be kept below a 1 percent concentration. However, this control has not produced a significant reduction in worker exposure to CO, when factors (ventilation, type of work tasks, and management of vehicle fleet) specific to companies are taken into account. Consequently, a reduction in CO emissions below the threshold of 0.3 percent should be considered. The experience acquired with propane-fueled ice resurfacers can be used to determine the effect of combustion parameters on exhaust gas emissions. It is known that a reduction in CO emissions from ice resurfacers resulted in the appearance of nitrogen oxides (NOx) and eventually in nitrogen dioxide (NO2) poisoning. Few publications present NOx results in relation to the CO measured in the exhaust gases of propane-fueled vehicles. The objective of this study is to define the level to which CO emissions can be reduced without increasing NOx concentrations. This real-situation study quantified the CO, NO, and NOx in the exhaust gases of a fleet of propane-fueled forklifts in relation to the mixture ratio. The results show the impact of the motor speed and mixture ratio on the CO, NO, and NO2 concentrations. They confirm an increase in NOx concentrations when CO concentrations are reduced. They also show that proper maintenance of forklifts combined with optimal adjustments can reduce CO and NOx emissions. The study proposes a compromise between CO and NOx emissions by taking into account worker health and safety as well as vehicle performance. Monitoring must be done to control air quality in work areas and worker exposure to CO and NO2. A forklift preventive maintenance program and general building ventilation are the favored and recommended means of control.

This study uses Las Vegas near-road measurements of carbon monoxide (CO) and nitrogen oxides (NOx) to test the consistency of onroad emission constraint methodologies. We derive commonly used CO to NOx ratios (ΔCO:ΔNOx) from cross-road gradients and from linear regression using ordinary least squares (OLS) regression and orthogonal regression. The CO to NOx ratios are used to infer NOx emission adjustments for a priori emissions estimates from EPA’s MOtor Vehicle Emissions Simulator (MOVES) model assuming unbiased CO. The assumption of unbiased CO emissions may not be appropriate in many circumstances but was implemented in this analysis to illustrate the range of NOx scaling factors that can be inferred based on choice of methods and monitor distance alone. For the nearest road estimates (25m), the cross-road gradient and ordinary least squares (OLS) agree with each other and are not statistically different from the MOVES-based emission estimate while ΔCO:ΔNOx from orthogonal regression is significantly higher than the emitted ratio from MOVES. Using further downwind measurements (i.e., 115m and 300m) increases OLS and orthogonal regression estimates of ΔCO:ΔNOx but not cross-road gradient ΔCO:ΔNOx. The inferred NOx emissions depend on the observation-based method, as well as the distance of the measurements from the roadway and can suggest either that MOVES NOx emissions are unbiased or that they should be adjusted downward by between 10% and 47%. The sensitivity of observation-based ΔCO:ΔNOx estimates to the selected monitor location and to the calculation method characterize the inherent uncertainty of these methods that cannot be derived from traditional standard-error based uncertainty metrics.

Mechanic of the Jagiellonian University Władysław Antoni Grodzicki and His Gas Liquefiers One of the significant achievements in Polish science was the liquefaction of oxygen, air, and other gases in 1883 by the Jagiellonian University professors – Zygmunt Wróblewski and Karol Olszewski. Over the next few years, Krakow became one of the leading units in researching the physicochemical properties of gases. The mechanical workshop of the Jagiellonian University, which produced custom-made laboratory devices for liquefying gases, also gained recognition. The devices were designed by Karol Olszewski, a professor of chemistry at the Jagiellonian University, who modelled them on the countercurrent condenser by William Hampson. The apparatuses were made by the university mechanic, Władysław Grodzicki (1864–1927), who held this post in the years 1897–1927. He offered three types of apparatuses: a cased apparatus, a demonstration apparatus for air liquefaction, and a universal apparatus for liquefaction of air and hydrogen. In order to test how they functioned, a complete gas liquefaction apparatus was installed in the laboratory (including purifiers, a compressor, etc.). These devices were bought by European research institutions, universities, and schools. Grodzicki’s activity contributed to the popularisation of research on low temperatures conducted at the Jagiellonian University. At the same time, it was one of the few Polish companies offering high-class scientific instruments.

This study explores the combustion behavior of three biomass pellet types—wood (W), sunflower husk (SH), and a mixture of wood and sunflower husks (W/SH)—in a residential hot water boiler. Experiments were carried out under two air supply regimes (40%/60% and 60%/40% primary to secondary air) to measure flue gas concentrations of oxygen (O2), carbon monoxide (CO), and nitrogen oxides (NOx). The results indicate that SH pellets generate the highest emissions (CO: 1095.3 mg/m3, NOx: 679.3 mg/m3), while W pellets achieve the lowest (CO: 0.3 mg/m3, NOx: 194.1 mg/m3). The mixed W/SH pellets produce intermediate values (CO: 148.7 mg/m3, NOx: 201.8 mg/m3). Overall boiler efficiency for all tested fuels ranged from 90.3% to 91.4%. Numerical simulations using ANSYS CFX (2024 R2 (24.2)) were performed to analyze temperature distribution, flue gas composition, and flow fields, showing good agreement with experimental outlet temperature and emission trends. These findings emphasize that both pellet composition and air distribution significantly influence efficiency and emissions, offering guidance for optimizing small-scale biomass boiler operation.

Emissions of major air pollutants including carbon monoxide (CO), nitrogen oxides (NOx) and mercury (Hg) were studied at two sewage sludge fluidized bed combustion (FBC) plants. Both the North West Bergen (NWB) County Utility Authority and the Little Miami (LM) plants have air pollution control systems (APCS) that are of the wet type. Various operating conditions such as temperature, excess air, fuel and feed properties, concentration of calcium chloride, and the method of operating were investigated to determine their effect on the emissions. Results of the study reveal that NOx increase with increased bed temperatures and excess air. CO is lower at higher freeboard temperatures. Both CO and NOx emissions are strongly dependent on the feed characteristics. CO and NOx fluctuate more with higher sludge solid content (TS). They increase not only with TS, but also with the sludge volatile solids (VS) and its heat content. NOx increase with the ratio of sludge oxygen over sludge nitrogen concentration. They are also higher with fuel oil than with natural gas when selected as the auxiliary fuel source. CO and NOx emissions are also higher and fluctuate more when the operation is not run consistently; when the feed quality is inconsistent, or when the feeding is intermittent or interrupted, or when the roof sprays are activated. It is believed that the feed characteristics and mode of operating affect the flame temperature and the excess air surrounding the combusting materials, which in turn have an impact on CO and NOx emissions. While some of the mercury (Hg) vapor is removed by condensation due to flue gas cooling, the addition of calcium chloride to the feed has shown a clear reduction in both emissions of NOx and Hg. It is believed that calcium chloride can generate strong oxidants, promoting the oxidation of both elemental mercury and NOx into more soluble forms, which can then be separated from the exhaust gas in a wet scrubber.

Examining low nitrogen oxides combustion in iron ore sintering: Utilization of reductants

In this paper we access the effects of two atmospheric variables (temperature and relative humidity) on two important pollutants in the atmosphere (Nitrogen oxides (NOx) and carbon monoxide (CO)) by using one year (2016) data of Addis Ababa. Temperature has impact on atmospheric mixing and cause for the reduction of NOx as temperature increases. There are positive correlation between temperature and CO concentration from January to April with (R2 = 0.69), negative correlation from May to August with (R2 = 0.92) and no correlation for the remaining months. NOx and CO have moderate positive and negative correlation with relative humidity during the months January-April (R2 = 0.294 for NOx and R2 = 0291 for CO) and in the months May-August are R2 = 0.97 and R2 = 0.15 for NOx and CO respectively. But there are no clear correlation between the NOx and CO with relative humidity from September-December. NOx concentrations during wet season was almost about twice that of the dry season, but no such difference was observed in the case of CO. The seasonal average air temperature in wet season is relatively lower than dry season. NOx exhibited positive and CO negative seasonal correlations with relative humidity.

Vehicle emissions trapping materials: Successes, challenges, and the path forward

This study utilizes the National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics Laboratory three‐dimensional global chemical transport model to quantify the impacts of biomass burning on tropospheric concentrations of carbon monoxide (CO), nitrogen oxides (NOx), and ozone (O3). We construct updated global sources that emit 748 Tg CO/yr and 7.8 Tg N/yr in the surface layer. Both sources include six types of biomass: forest, savanna, fuelwood, agricultural residues, domestic crop residues (burned in the home for cooking and/or heating), and dried animal waste. Timing for the burning of forest, savanna, and agricultural residues is based upon regional cultural use of fire, vegetation type, local climate, and information gathered from satellite observations, while emissions from the burning of fuelwood, domestic crop residues, and dried animal waste are constant throughout the year. Based on agreement with observations, particularly of CO, we conclude that the collective uncertainty in our biomass burning sources is much less than the factor of two suggested by previous estimates of biomass burned in the tropics annually. Overall, biomass burning is a major source of CO and NOxin the northern high latitudes during the summer and fall and in the tropics throughout most of the year. While it contributes more than 50% of both the NOxand CO in the boundary layer over major source regions, it has a much larger global impact on the CO distribution in comparison to either NOxor O3, contributing 15 to 30% of the entire tropospheric CO background. The only significant biomass burning contribution to NOxat 500 mbar, due to the short lifetime of NOxin the lower troposphere, is a plume occurring July through October in the Southern Hemisphere subtropical free troposphere, stretching from South America to the western Pacific. The largest impacts on O3are limited to those regions where NOximpacts are large as well. Near the surface, biomass burning indirectly contributes less than half of the total O3concentrations over major tropical source regions, up to 15% throughout the year in the tropics, and 10 to 20% throughout the Southern Hemisphere during September through November. At 500 mbar, the largest contribution to O3(20–30%) is correlated with the NOxplume during July through November. Biomass burning contributes less than 15% of either NOxor O3in the upper troposphere.

This study deals with some methods of making human exposure estimates, aimed at describing the human exposure for selected air pollutants in Sweden that are suspected carcinogens. Nitrogen oxides (NOx) have been chosen as an indicator substance for estimating the concentration of the urban plume. Earlier investigations have shown that the traffic in Swedish cities contributes around 85% to the measured NOx concentrations, and that most of the mutagenicity in urban air originates from traffic. The first section of this paper describes measurements in Stockholm of some unregulated light hydrocarbons, such as ethene, ethyne, propane, propene, butane, and isobutane. In addition, measurements of some volatile aromatic hydrocarbons are presented. Simultaneous measurements of carbon monoxide (CO) were made. The ratios between CO and the individual specific compounds were determined by linear regression analysis. By analysis of relationships between CO and NOx, NOx concentrations can be used as a tracer to describe the exposure for these specific compounds. NOx are considered to be a better tracer than CO, because NOx or NO2 values exist for many places over a long time, while CO is measured mostly in streets with high concentrations. At low concentrations, instruments that measure normal CO levels give no detectable signals. Through use of atmospheric dispersion models and models that describe how people live and work in urban areas it has been possible to describe the average exposure to NOx in cities of different sizes. The exposure to NOx for people living in the countryside has also been estimated. In this way, it has been possible to calculate the average exposure dose for NOx for the Swedish population. This figure is 23 micrograms/m3. By use of the relationships between NOx and specific compounds the average dose has been calculated for the following compounds: polyaromatic compounds (PAH); ethene, propene, and butadiene; benzene, toluene, and xylene; formaldehyde and actaldehyde; nickel, chromium (VI), arsenic, and cadmium; asbestos; and silicon.

Concerns about environmental pollution and global warming are increasing the demands on modern engines, which are expected to operate at high efficiency and at the same time have minimal emissions. Emission models to predict the level of engine exhaust gas have become increasingly important in the automotive industry. In this paper, a rapid chemical equilibrium composition model is applied to calculate the main combustion products from spark ignition engine such as carbon monoxide (CO), carbon di oxide (CO2), oxygen(O2), water vapor (H2O), nitrogen (N2) and nitrogen oxides (NOx) emission. A two-zone thermodynamic heat transfer model has been implemented and combined with chemical kinetic models such as Zeldovich mechanism and Tan-Lu mechanism based on equilibrium concentration for calculating nitrogen oxides (NOx) and carbon monoxide (CO) emissions respectively from a gasoline spark ignition engine. Nitrogen oxides (NOx), carbon monoxide (CO) and carbon di oxide (CO2) are the three major combustion products that are harmful for the environment and human health. A number of MATLAB programs are used for emission calculations and thermodynamic simulation of SI engine. It has been found that at slightly lean fuel-air equivalence Ratio (0.95 to 0.98) and moderate combustion temperature (2200 k - 2500 k), pollutant formation is minimum. Other engine parameters such as engine speed, spark timing, compression ratio are also optimized. The model is validated by experimental data from a gasoline direct injection SI research engine.

On-road vehicle emissions of carbon monoxide (CO), nitrogen oxides (NOx), and volatile organic compounds (VOCs) during 1995–2009 in the Atlanta Metropolitan Statistical Area were estimated using the Motor Vehicle Emission Simulator (MOVES) model and data from the National Emissions Inventories and the State of Georgia. Statistically significant downward trends (computed using the nonparametric Theil-Sen method) in annual on-road CO, NOx, and VOC emissions of 6.1%, 3.3%, and 6.0% per year, respectively, are noted during the 1995–2009 period despite an increase in total vehicle distance traveled. The CO and NOx emission trends are correlated with statistically significant downward trends in ambient air concentrations of CO and NOx in Atlanta ranging from 8.0% to 11.8% per year and from 5.8% to 8.7% per year, respectively, during similar time periods. Weather-adjusted summertime ozone concentrations in Atlanta exhibited a statistically significant declining trend of 2.3% per year during 2001–2009. Although this trend coexists with the declining trends in on-road NOx, VOC, and CO emissions, identifying the cause of the downward trend in ozone is complicated by reductions in multiple precursors from different source sectors.Implications:Large reductions in on-road vehicle emissions of CO and NOx in Atlanta from the late 1990s to 2009, despite an increase in total vehicle distance traveled, contributed to a significant improvement in air quality through decreases in ambient air concentrations of CO and NOx during this time period. Emissions reductions in motor vehicles and other source sectors resulted in these improvements and the observed declining trend in ozone concentrations over the past decade. Although these historical trends cannot be extrapolated to the future because pollutant concentration contributions due to on-road vehicle emissions will likely become an increasingly smaller fraction of the atmospheric total, they provide an indication of the benefits of past control measures.

Korea Forest Service has supplied 76 industrial wood pellet boilers from 2011 to 2015 through subsidy programs. Since carbon monoxide (CO) and nitrogen oxides (NOx) generated during boiler combustion are substances that lead to death in the case of acute poisoning, it is very important to reduce emissions. Therefore, the CO and NOx emission values of 63 boilers excluding the hot air blower and some boilers initially supplied were analyzed. The emission factor was also calculated from the measured exhaust gas concentration (based on exhaust gas O2 concentration of 12%). The average value of CO emitted from industrial wood pellet boilers was 49 ppm and it was confirmed that the CO concentration was decreasing as the years passed. The emission factor of CO was 0.73 g/kg. The average value of NOx emitted from industrial wood pellet boilers was 67 ppm and the emission factor of NOx was 1.63 g/kg. Unlike CO, there was no tendency to decrease according to the installation year. Both CO and NOx measurements met the limits of the Ministry of Environment. These NOx emission factors were compared with the NOx emission factors produced by certified low NOx burners. The NOx emission factor of industrial wood pellet boilers was about 1.9 times that of certified low NOx LNG combustors and about 0.92 times that of coal combustion.

У складі викидів у навколишнє середовище в процесі спалювання твердого палива найбільша частка припадає на оксиди нітрогену, карбону та різноманітні шлаки. Зараз виділяють три основних джерела утворення оксидів азоту: «термічні», «швидкі» і «паливні». Кожне з джерел утворення оксидів азоту має свій механізм утворення. Оксид карбону (ІІ) утворюється в умовах неповного окиснення вуглецю палива наряду з альдегідами, органічними кислотами і іншими вуглеводнями. Одним із варіантів зменшення викидів в атмосферне повітря і підвищення ступеню вигоряння твердого палива є використання електронно-каталізу, суть якого полягає в інтенсифікації первинних ендотермічних стадій реакції горіння твердого палива, які базуються на використанні спрямованої дії штучно створеної низькотемпературної плазми з упорядкованим рухом «повільних» електронів. Як джерело «повільних» електронів використовували діелектричний бар’єрний розряд. За електронно-каталітичного спалювання досягнуто зменшення концентрації нітроген (ІІ) оксиду досягає майже 49 %, а карбон (ІІ) оксиду, за тієї ж напруги, майже 33 %. Ступінь вигоряння палива збільшується на 30 %. Зменшення утворення нітроген (ІІ) оксиду можна пояснити тим, що використання електрокаталізу пригнічує утворення «термічних» та «паливних» оксидів азоту за рахунок фіксації атомарного кисню. Пригнічення утворення швидких молекул нітроген (ІІ) оксиду відбувається за рахунок збільшення теплового ефекту процесу, що протікає. Карбон (II) оксид також, завдяки кращій дифузії кисню і потоку «повільних» електронів, доокиснюються до карбон (IV) оксиду та відбувається збільшення кількості радикалів НО•.

Experimental study on the emission characteristics and performance of PNA coupled aftertreatment system with different catalyst loading