Reduction In Carbon Monoxide Emissions Research Articles

Experimental Study of Management Systems for Emission Reduction in Ignition Engines

The present study aims to investigate the amount of exhaust gases emissions of a 4-cylinder gasoline-ignition engine. An experimental study of an ignition engine management system has been conducted for emissions optimization, using Winols specialized software. In order to achieve a steady state conditions in the experiments, the temperature of the water and engine oil before each test reached the engine's working temperature (90°C) to allow various parts of the engine to remain stable and the tests are performed in in-line engine operation. Two sets of tests with idle (850-900 rpm) and mid-range (2500 rpm) are considered. Experiments were performed for three identical engines with different mileages and obtained results were discussed. According to the obtained results, after applying changes to the engine management system, a 22% reduction in the unburned hydrocarbon emission in both cases was obtained. Furthermore, it is found that 31 and 5% reduction in carbon monoxide emissions in the idle and mid-range were obtained, respectively. As a result of applying these changes, there was a reduction of 1.4% in NOx emission in the idle case and a decrease in about 19% at 2500 rpm.

High-spatiotemporal-resolution inverse estimation of CO and NOx emission reductions during emission control periods with a modified ensemble Kalman filter

Emission control strategies are among the most effective ways to improve air quality, but the emissions reduced were usually estimated with high uncertainty. Here we present a modified ensemble Kalman filter (EnKF) to reduce the uncertainties of carbon monoxide (CO) and nitrogen oxides (NOx) emissions at one week and 5 km resolution by assimilating surface CO and nitrogen dioxide (NO2) observations. By decoupling analysis steps from ensemble simulations, the modified EnKF avoids filter divergence and enables reuse of costly ensemble simulations, making high-spatiotemporal-resolution inversion affordable. This method is tested by a set of observing system simulation experiments. By assimilating synthetic observations from 400 sites, the errors of CO and NOx emissions over Beijing-Tianjin-Hebei (BTH) in the a priori emission inventory are reduced by 78% and 76%, respectively. Further application of this method estimates the emission reductions during China's Victory day parade using real surface observations. The changes of the emissions in each city are identified by this method, which suggests that the CO and NOx emissions over BTH region during the parade are reduced by 36% and 44%, respectively. Using the inversed emission inventory, the biases of CO and NO2 simulations during the parade are reduced by 95% and 91%, respectively. This highlights the potentials of this method for improving high-spatiotemporal-resolution emission estimation.

Carbon monoxide reduction in the flue gas during biochar production from oil palm empty fruit bunch

Biomass carbonization technology is implemented to produce charcoal with high-calorific content. However, this technology releases pollutant gases, which adversely affect ambient environment and human health. This study proposed a catalytic gas treatment method using platinum-supported alumina catalyst (Pt/γ-Al2O3) for carbon monoxide emission reduction in oil palm empty fruit bunch carbonization. Carbonization released a rather high carbon monoxide concentration of 5558 ± 53 mg m−3 in the flue gas, exceeding the permissible limit of 1000 mg m−3. At 2.5 wt% of catalyst dosage, the carbon monoxide emission substantially was reduced to 595 ± 9 mg m−3, achieving 89.3% carbon monoxide removal efficiency. This was due to oxidation by the platinum-supported alumina catalyst (Pt/γ-Al2O3), which was done at low temperature, thus transforming carbon monoxide into carbon dioxide. The catalyst demonstrated reusability, attaining >80% carbon monoxide removal efficiency for 5 consecutive carbonization cycles. The biochar produced contained a high energy content of 24.6 ± 0.7 MJ kg−1, which was suitable to be used as a coal substitute.

The Impact of COVID-19 on Air Pollution: Evidence from Global Data

The COVID-19 pandemic is producing significant economic and social cost globally. As a cure or a treatment is yet unavailable, strict social distancing is considered the key way to prevent it. Amid all negatives, one benefit of the pandemic being discussed is the reduction in air pollution, caused by strict mobility restrictions and confinement measures implemented across the world. Despite the flurry of on-going narratives, empirical examination of the link between mobility changes and air pollution during the COVID-19 period remains unavailable. This paper examines the short and long run impacts of mobility changes on carbon monoxide (CO) emissions, by employing pooled mean group, mean group, and dynamic fixed effect estimators on a panel of 35 countries covering daily data from 15 February to 17 April 2020 - a period when most countries went into strict lockdowns. Findings show a consistent evidence at the all-countries level and across regions that long-run indoor mobility increases reduce CO emissions, while outdoor mobility increases across places such as transit stations, workplaces, grocery & pharmacies, retail & recreation, and parks drive up emissions. Among the regions studied, Europe excluding the EU and the UK sees the largest emissions reduction from increased indoor mobility. While short-run effects are limited, emissions in US-Canada respond to indoor and outdoor mobility changes both in the short and long run. My paper’s findings validate and qualify the on-going discussion and call for policies to curb unnecessary outdoor mobility to maintain air quality in the post-pandemic world.

Carbon monoxide in the process of uncontrolled combustion - occurrence, hazards and first aid

Carbon monoxide (CO) is a highly toxic gas, odorless and tasteless, belongs to the group of flammable and explosive gases, and is produced by incomplete combustion of fossil fuels in power plants, automobiles, households and various industrial processes. It is very active in chemistry, reacts with many metals, sulfur, chlorine, etc.As it is flammable and explosive gas, it is a significant risk of its ignition if found near an open flame. Carbon dioxide, dry chemical or water is used for quenching, [1].The concentration of 1 % carbon monoxide in the air is lethal. Carbon monoxide is toxic and indirectly contributes to global warming as a precursor to ozone. Carbon monoxide emissions from the atmosphere come from a number of sources, most of all traffic.The introduction of catalytic converters, and especially diesel vehicles, has significantly reduced carbon monoxide emissions in the EU and in countries in transition.

Emission reduction in CI engine using biofuel reformulation strategies through nano additives for atmospheric air quality improvement

The main objective of this research work is to investigate the effect of multiwalled carbon nanotubes and cerium oxide nano-additives in lemon and orange peel oil biofuel blends in compression ignition engine. Eight different blends are prepared using lemon and orange peel oil in 20% volume ratio with diesel in which nanoparticles are added at two concentrations (50 and 100 ppm). The study revealed that brake thermal efficiency of carbon nanoparticle and cerium oxide addition with biofuels is marginally lower then diesel fuel. Furthermore, brake specific energy consumption for biofuel samples with and without nanoparticles are substantially lower than diesel fuel and in particular, the 50 ppm cerium oxide with lemon peel oil blend has resulted in 16.4% reduction in brake specific energy consumption. The Carbon nanotubes and cerium oxide in orange oil exhibit higher heat release rate high in-cylinder pressure than other fuel respectively. Moreover, the cerium oxide in orange oil at 50 ppm concentration has resulted in 53.8% reduction in carbon monoxide emission and similar kind of reduction is also observed in hydrocarbon emission as well. On the other hand, the nanoparticles addition with lemon peel and orange peel at all concentrations has shown only marginal reduction in NOx emission.

Experimental study on the effects of exhaust heat recovery system (EHRS) on vehicle fuel economy and emissions under cold start new European driving cycle (NEDC)

Over the decades, unremitting efforts have been made to achieve energy conservation and emission reduction throughout the world. While for a vehicle engine, a great deal of the fuel energy is wasted as exhaust heat. Based on a novel exhaust heat recovery system devised and modified on a vehicle exhaust channel, the chief objective of this study is to improve the vehicle economy and emissions under cold start. Therefore, a detailed experimental investigation was conducted on the chassis dynamometer (CD) under cold start NEDC at 25 °C and −7 °C temperatures. And the method of comparative analyses of the coolant temperature, gasoline fuel consumption and exhaust emissions including total hydrocarbon (THC), carbon monoxide (CO) and nitrogen oxide (NOX) have been obtained to reveal the effects of EHRS on vehicle economy and emissions under cold start. The results show that, since the coolant temperature can be quickly increased with EHRS to shorten engine warm-up time under cold start, vehicle economy is enhanced during NEDC. Moreover, the device of EHRS can effectively alleviate the combustion deterioration and wall frame quenching effect in the cylinders under cold start, which greatly decreases THC emission. Although the excess air coefficient cannot be changed by EHRS, it can improve the combustion environment in cylinders, which contributes to the reduction of CO emission. It is unexpected to find that NOX emission is also decreased with EHRS actuation, which can be explained by a new theory called Fenimore mechanism. All these aims to provide helpful preliminary work for vehicles to meet the upcoming stringent limit of the real driving emission (RDE) of CHINA 6.

Three decades of on-road mobile source emissions reductions in South Los Angeles

ABSTRACT In May 2018, the University of Denver repeated on-road optical remote sensing measurements at two locations in Lynwood, CA. Lynwood area vehicle tailpipe emissions were first surveyed in 1989 and 1991 because the area suffered from a large number of carbon monoxide (CO) air quality violations. These new measurements allow for the estimation of fuel-specific CO and total hydrocarbon (HC) emissions reductions, changes in the longevity of emission-control components, and the prevalence of high emitters in the current fleet. Since 1989 CO emissions decreased approximately factors of 10 (120 ± 8 to 12.3 ± 0.2 gCO/kg of fuel) and 20 (210 ± 8 to 10.4 ± 0.4 gCO/kg of fuel) at our I-710/Imperial Highway and Long Beach Blvd. sites, respectively. These reductions are also reflected in the local ambient air measurements. Tailpipe HC emissions have decreased by a factor of 25 (50 ± 4 to 2.1 ± 0.3 gHC/kg of fuel) since 1991 at the Long Beach Blvd. location. The decreases are so dramatic that the vast majority of vehicles now have HC measurements that are indistinguishable from zero. The decreases have increased the skewedness of the emissions distribution with the 99th percentile now responsible for more than 37% (CO) and 28% (HC) of the totals. Ammonia emissions collected in 2018 at both Lynwood locations peak with 20-year-old vehicles (1998 models), indicating long lifetimes for catalytic converters. In 1989 and 1991, the on-road Lynwood fleets had significantly higher emissions than fleets observed in other locations within the South Coast Air Basin. The 2018 fleets now have means and emissions by model year that are consistent with those observed at other sites in Los Angeles and the U.S. This indicates that modern vehicle combustion management and after-treatment systems are achieving their goals regardless of community income levels. Implications: Recent on-road vehicle emission measurements at two locations in the Lynwood, CA area, first visited in 1989, found significant fuel specific CO and HC emission reductions. CO emissions have decreased by a factor of 10 and 20 at each location and HC emissions have declined by a factor of 25. This has increased the skewedness in both species emissions distribution. The 2018 fleets have means and emissions by model year that are now consistent with those observed at other U.S. sites indicating that modern vehicle emissions control advancements are achieving their goals regardless of community income levels.

Copper-Exchanged Philippine Natural Zeolite as Potential Alternative to Noble Metal Catalysts in Three-Way Catalytic Converters

Natural and synthetic zeolites are microporous hydrated aluminosilicate minerals known for their high thermal stability and their use in various catalytic applications. In this study, the potential of modified Philippine natural zeolite as a cheap alternative to noble metal catalysts in three-way catalytic converters was investigated. The natural zeolite (Z) of the heulandite variety was treated using hydrochloric acid and then ion-exchanged with sodium (NaZ) and copper (CuZ) ions in succession. Energy-dispersive X-ray spectroscopy analysis revealed successful replacement of sodium and other exchangeable cations by copper in the zeolite at 1.19%. Morphological features using scanning electron microscope have shown uniform dispersion of copper as well as uniform particle distribution. In the emission study, a stationary two-stroke 125 cm3 spark-ignition gasoline engine motorcycle at three different speeds of 10 (low), 40 (medium) and 70 (high) kilometers per hour (kph) was used to investigate the catalytic properties of CuZ with the non-catalytic setup as baseline. Using the modified zeolite catalyst, emission test results have shown significant reduction in carbon monoxide (CO) and hydrocarbon (HC) emissions in all speeds, while nitrogen monoxide (NO) emission was significantly reduced from medium to high speeds, suggesting that NO reduction was highly influenced by reaction temperature. Highest reduction in CO emission was 59.61% at medium speed, while highest HC and NO emissions were 66.52% and 76.63%, respectively, at high speed. While further tests are recommended, results show the potential of modified Philippine natural zeolite as a cheap alternative material for three-way catalytic converters.

Experimental study of PM emissions from wood pellet stoves with an innovative burning pot

In this study, results of an extensive set of experiments on a wood pellet stove model equipped with innovative burning pots are presented. Tests have been performed to investigate the relations between design data and operation parameters of the stove and its emissions. In particular, carbon monoxide (CO) and particulate matter (PM) emissions are correlated to the burning-pot depth.The burning pot A, adopted by AICO S.p.A, allows to obtain near-to-zero CO emissions and low PM emissions: however, PM emissions reduction with respect to standard burning pots is not as enhanced as CO emission reduction. Here it is shown that a further reduction of PM emissions (down to 6-16 mg/Nm3) can be attained increasing the burning pot depth.Experiments show also an increment of PM emissions in subsequent tests in the same day: there is an apparent dependence of PM release on the time from ignition. It is likely that this effect is due to ashes accumulation on the bottom of the burning pot and to their interaction with the primary air stream that flows over them.

Effect of electromagnet-based fuel-reforming system on high-viscous and low-viscous biofuel fueled in heavy-duty CI engine

In the present study, a high-viscous biofuel, namely wheat germ oil (WGO), and a low-viscous biofuel, namely pine oil (PO), are used in a twin-cylinder diesel engine. The fuel ionization filter is fitted with a permanent magnet, an electromagnet, and the combination of permanent magnet and electromagnet, and their effect on the engine performance, emission, and combustion is studied. A fuel ionization filter placed in the fuel line, before the injection pump, ionizes the fuel molecules and increases the rate of disintegration of droplets due to a decrease in viscosity and surface tension. The tests are performed at a constant engine speed of 1500 rpm with loads varying from no load to full load at intervals of 25%. As compared to diesel, the engine operation with ionization filter increased brake thermal efficiency and reduced the fuel consumption for both PO and WGO. The increase in brake thermal efficiency is in the order: permanent magnet, electromagnet, and combination of electromagnet and permanent magnet. The magnetic field strength of electromagnet is higher than permanent magnet which tends to increase the ionization of the fuel. When both the magnets are combined, the magnetic field strength further increases resulting in more ionization of the fuel. It is also perceived that magnetic effect reduces the viscosity of the fuel. Regulated emissions, namely unburned hydrocarbons (HC), carbon monoxide (CO), and smoke emissions, reduced, whereas NOx emissions increased with WGO and ionization filter. With pine oil and ionization filter, all the regulated emissions decreased as compared to neat pine oil. The reduction in HC, CO, and smoke emissions was highest for combination of electromagnet and permanent magnet followed by electromagnet and permanent magnet. The study shows that combination of permanent magnet and electromagnet resulted in the best engine performance and emission characteristics.

Performance and emission characteristics of a compression ignition (CI) engine operated with beauty leaf biodiesel

In this investigation, diesel and beauty leaf (Calophyllum inophyllum L.) biodiesel (BLB)-diesel blends (B5, B10 and B20) were used to evaluate the performance and emission characteristics of a compression ignition (CI) engine. During the experiment, the speed of the engine was varied from 1200 rpm to 2400 rpm at 200 rpm interval. The results indicated that the performance characteristics, such as BP and BSFC in biodiesel blended fuel increases with increase in engine speed at full load condition with a few exceptions in BSFC at 1400 rpm. On the other hand, BTE and BMEP in biodiesel blended fuel decreases with increase in engine speed at 100% load with few exceptions at 1400 rpm. The results also revealed that the BP, BTE and BMEP are lower, whereas, the BSFC is higher in biodiesel blended fuel in comparison to diesel. In terms of emission characteristics, the results indicated that the emission of nitrogen oxides (NOx) increases, whereas, carbon monoxide (CO), hydrocarbon (HC), and particulate matter (PM) decreases with increase in engine speed at full load condition. The results also shown that the use of biodiesel-diesel blends in CI engine led to the significant reduction in CO, HC and PM emissions in comparison to conventional diesel. On the other hand, it has been observed that the NOx emissions are increased in biodiesel-diesel blends when they are compared to diesel.

Numeric Simulation of the Effect of Varying Velocities on Catalytic Converter and Exhaust Gas Emission

Fossil fuel-powered vehicles are the most significant contributor to air pollution nowadays. They emit substances that are harmful to both human and environment. Carbon monoxide (CO) and Hydrocarbon (HC) is the most common harmful exhaust gases found in the environment. One of the technologies used for reducing CO emissions is catalytic converters. The catalytic converters usually installed in the exhaust system. The numeric study was conducted on the interaction of flow, reaction, and thermal effects in the form of a 2D model of the catalytic converter. Simulation using Fluent software was then used to find out the extent of the catalyst effects on CO gas absorption when velocities were 6.3 m/s, 15 m/s, and 20 m/s. The simulation revealed that CO mass fraction and temperature around the exhaust channel increased as the velocity increased.

Application of Palm Oil Biodiesel Blends under Idle Operating Conditions in a Common-Rail Direct-Injection Diesel Engine

This study describes the effects of palm oil biodiesel blended with diesel on the combustion performance, emission characteristics, and soot morphology in a 4-cylinder common-rail direct-injection (CRDI) diesel engine. The operational condition is idle speed, 750 rpm (the lowest speed of the test engine without any operation by driver), and the load conditions of the engine are 0 Nm and 40 Nm. Five kinds of biodiesel fuels are blended with diesel in 0%, 10%, 20%, 30%, and 100% proportions by volume. A pilot injection was applied at BTDC 15 °CA and 20 °CA. Part of the pilot injection affects the combustion of the main injection due to the deterioration of the spray because of the high viscosity of palm oil biodiesel. Palm oil biodiesel is sufficient to keep the engine stable in an idling state, but the fuel economy deteriorated. The deterioration of the spray due to the high viscosity of palm oil biodiesel is offset by the effect of oxygen content and high cetane number, resulting in a constant nitric oxide (NOx) emission. However, particulate matter (PM) is reduced. When the engine load is increased, the carbon monoxide (CO) emission amount increased because of the insufficient intake air and oxygen content to reduce the fuel-rich areas. However, when the palm oil biodiesel blend ratio was above a certain level, the influence of oxygen content in the palm oil biodiesel increased, resulting in reduced CO emission levels. Hydrocarbon (HC) was reduced by oxygen atoms in palm oil biodiesel. The sizes of particulates emitted from diesel engine using palm oil biodiesel decreased with an increased blend ratio because of oxidization of hydrocarbons absorbed on PM.

Acetalization Catalysts for Synthesis of Valuable Oxygenated Fuel Additives from Glycerol

Biodiesel is one of the most attractive sources of clean energy. It is produced by the transformation of vegetable oils with up to 10% formation of glycerol as a by-product. Therefore, development of new approaches for processing bio-glycerol into such value-added chemical compounds as solketals is necessary. Thus, various six- and five-membered cyclic compounds can be prepared by acetalization of glycerol with aldehyde or ketone. The resulting glycerol oxygenates are excellent fuel additives that increase viscosity, octane or cetane number, and stability to oxidation. In addition, these products significantly reduce carbon monoxide emissions from standard diesel fuel. In this review, we highlight recent advances in the glycerol valorization for the sustainable production of bio-additives. The review includes a discussion of the innovative and potential catalysts to produce solketals.

Mixtures of n-butanol and iso-butanol blended with diesel: experimental investigation of combustion characteristics, engine performance and emission levels in a compression ignition engine

The isomers of butanol have slightly different properties, which can be exploited to improve combustion characteristics. To investigate the potential of this concept, normal-butanol (nB) and iso-butanol (isoB) were blended together in four different ratios (5% of each, 10% of each, and 7% plus 13% of each in both variations, by volume) with conventional diesel. The experimental data were analyzed via analysis of variance to evaluate significant differences between engine parameters. Brake power for the 5% isoB–5% normal-butanol–90% diesel blend was slightly improved while specific fuel consumption was increased with the increase in all dual blends. The high blend ratios of isoB (10% and 13% isoB) produced higher peak in-cylinder pressures and heat release rates as well as a substantial reduction in carbon monoxide emissions. The higher blend ratios of nB (10% and 13% nB) produced much lower unburnt hydrocarbon emissions because the energy required to crack the C–H bonds of nB is less than that required for isoB. Therefore, the hydrocarbons are more easily oxygenated. A slight reduction was found in NOx emissions when increasing either nB or isoB, with nB being slightly more effective. Therefore, a blend of n- and isoB could be a promising alternative to a single isomer additive (iso/nB) to optimize engine performance.

Gaseous and particulate emissions from a chimneyless biomass cookstove equipped with a potassium catalyst

Approximately three billion people cook with solid fuels, mostly wood, on open fires or rudimentary stoves. These traditional cooking methods produce particulate matter and carbon monoxide known to cause significant respiratory health problems, especially among women and children, who often have the highest exposure. In this work, an inexpensive potassium-based catalyst was incorporated in a chimneyless biomass cookstove to reduce harmful emissions through catalytic oxidation. Potassium titanate was identified as an effective and stable oxidation catalyst capable of oxidizing particulate matter and carbon monoxide. Using a cordierite monolith to incorporate potassium titanate within a bespoke, rocket-style, improved cookstove led to a 36% reduction in particulate matter emissions relative to a baseline stove with a blank monolith and a 26% reduction relative to a stove with no monolith. Additionally, the catalytic stove reduced particulate matter emissions by 82%, reduced carbon monoxide emissions by 70%, and improved efficiency by 100% compared to a carefully tended, three-stone fire. Potassium titanate was also shown to oxidize carbon monoxide at temperatures as low as 500 °C, or as low as 300 °C when doped with copper or cobalt.

Performance analysis of a membrane‐based reformer‐combustor reactor for hydrogen generation

Hydrogen is mostly produced in conventional steam methane reforming plants. In this work, we proposed a membrane-based reformer-combustor reactor (MRCR) for hydrogen generation in order to improve heat recovery and overall thermal efficiency. The proposed configuration will also reduce the complexity in existing steam methane reforming (SMR) plants. The proposed MRCR comprises combustion zone, hydrogen permeate zone, and SMR zone. A computational fluid dynamics model was developed using ANSYS-Fluent software to simulate and analyze the performance of the proposed MRCR. Results show that high hydrogen yields were observed at high reformer pressures (RPs) and low gas hourly space velocities (GHSVs). Furthermore, by increasing the steam to methane ratio and addition of excess air in the combustion side, the hydrogen yield from the MRCR decreases. This is attributed to the reduction in the effective temperature of the hydrogen membrane. High RP, low GHSV, and low steam to methane ratio that increased the hydrogen yield also decreased carbon monoxide (CO) emissions. For an increased RP from 1 to 10 bar, the CO emission decreased by about 99%. The reduction in CO emission at high RP would be attributed to the effect of water gas shift reaction in the MRCR. Results of the extensive parametric study presented in this work can be used to determine the operating conditions based on tradeoffs between hydrogen yield (mole H2/mole CH4), hydrogen production rate (kg of H2/h), allowable CO emissions, and exhaust gas temperature for other applications such as gas turbine.

Advanced CFD modelling of air and recycled flue gas staging in a waste wood-fired grate boiler for higher combustion efficiency and greater environmental benefits

Grate-fired boilers are commonly used to burn biomass/wastes for heat and power production. In spite of the recent breakthrough in integration of advanced secondary air systems in grate boilers, grate-firing technology needs to be advanced for higher efficiency and lower emissions. In this paper, innovative staging of combustion air and recycled flue gas in a 13 MWth waste wood-fired grate boiler is comprehensively studied based on a numerical model that has been previously validated. In particular, the effects of the jet momentum, position and orientation of the combustion air and recycled flue gas streams on in-furnace mixing, combustion and pollutant emissions from the boiler are examined. It is found that the optimized air and recycled flue gas jets remarkably enhance mixing and heat transfer, result in a more uniform temperature and velocity distribution, extend the residence time of the combustibles in the hot zone and improve burnout in the boiler. Optimizing the air and recycled flue gas jet configuration can reduce carbon monoxide emission from the boiler by up to 86%, from the current 41.0 ppm to 5.7 ppm. The findings of this study can serve as useful guidelines for novel design and optimization of the combustion air supply and flue gas recycling for grate boilers of this type.

Performance and emissions of an engine fuelled by biogas of palm oil mill effluent

This research investigates the performance and emissions of an engine by biogas and gasoline. The experiments use biogas of palm oil mill effluent (POME) with turbocharger at engine loading conditions (100, 200, 300, 400, and 500 Watt). Specific fuel consumption and thermal efficiency are used to compare engine performance, and emission analysis is based on parameters such as carbon monoxide (CO), hydrocarbon (HC), carbon dioxide (CO2) and oxide (O2). The experimental data show that the maximum thermal efficiency when engine use biogas and gasoline is 20.44% and 22.22% respectively. However, there was CO emission reduction significantly when the engine using POME biogas.