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Purpose. Using mathematical modeling, to assess the feasibility of introducing a Selective Non-Catalytic Reduction (SNCR) system as a measure to reduce nitrogen oxide emissions from the production of iron ore pellets. To determine the peculiarities of using ammonia solution and urea solution as reagents for the SNCR process, the infl uence of the injection of these reagents on the temperature regime during iron pellet production, as well as assess the expected effi ciency of the SNCR method for purifi cation of exhaust gases from nitrogen oxides. Methodology. The research results have been obtained using CFD-modeling in the ANSYS Fluent software package. To model this process, a computational domain is constructed, which corresponds in size to the preheating zone (PRE zone) of the actual iron pellet production plant. Two series of calculations are performed for this domain: the fi rst, without adding a reagent, and the second, with a urea solution as a reagent for the SNCR system. Findings. For the fi rst series of calculations, the temperature fi eld and the pressure fi eld in the computational domain is obtained. Experimental research makes it possible to assert that the physical conditions of the mathematical model are close to those at a real plant for the production of pellets. In the second series of calculations, the temperature fi eld in the computational domain is obtained and the infl uence of the reagent injection of the SNCR system is determined, namely, the temperature decrease in the PRE zone of the pellet production plant by 10–25 °С. The expected effi ciency of reduction of nitrogen oxides using a 50 % urea solution is about 60 %. Originality. It has been revealed that the process of urea solution evaporation is intense, which accelerates the beginning of urea decomposition and, accordingly, the reduction reaction of nitrogen oxides. The temperature drop in the zone of moisture evaporation does not exceed 10–25 °C. The reagent injection (50 % urea solution) with a consumption of 219 kg/h does not signifi cantly aff ect the temperature regime in the PRE zone. Modeling the chemical reactions of the SNCR process with the injection of 50 % urea solution droplets through lances into the PRE zone chamber indicates a 60 % reduction in nitrogen oxide emissions. Practical value. The introduction of the SNCR system at pellet production plant can reduce nitrogen oxide emissions, which will have a positive impact on the environmental situation in metallurgical regions. [ABSTRACT FROM AUTHOR]

A study is presented on the enhancement of solar still (SS) performance by using chimney exhaust gases (EGs) passing through chimney channels under the still basin. The impact of the exhaust gas temperature on the SS temperature, productivity, efficiency, and freshwater yield cost is considered. The SS performance with the chimney is compared with that of conventional solar still. The study is performed under the hot and cold climate conditions of Upper Egypt. A complete transient mathematical model of the physical model including the solar still regions temperatures, yield, and heat transfer between the SS and the EGs is constructed. This model is solved by using Runge-Kutta method of fourth-order and programmed inside MATLAB software and validated using an experimental setup. The results show that the SS saline water temperature and freshwater yield rise with rising EGs temperatures. Furthermore, the impact of using EGs on the SS performance in winter is superior to that in summer, and also during the daytime is higher than that of night. Using chimney EGs at 75 °C and 125 °C enhances the daily freshwater yield of the SS by more than three times and about six times in winter, respectively, and about two and half times and more than three times in summer, respectively. Using EGs at 125 °C achieves a maximum solar still efficiency of 29.5% in winter and 49.5% in summer with an increase of 41% and 55.7%, respectively, and reduces its yield cost by 63.6% compared to conventional SS. [ABSTRACT FROM AUTHOR]

This white paper reviews previous studies on prospects for reducing CO2 emissions from trucks. It provides a new investigation into the feasibility of achieving an 80% reduction in CO2-equivalent (CO2e) greenhouse gas (GHG) emissions in the United States and California from trucks by 2050. The authors assess the technological and economic potential of achieving deep market penetrations of low-carbon vehicles and fuels, including vehicles operating on electricity, hydrogen, and biofuels. Achieving such a target for trucks will be very challenging and, if focused on hydrogen and electric zero emission vehicle (ZEV) technologies, will require strong sales growth beginning no later than 2025.View the NCST Project Webpage

The United States and California have made commitments to reduce energy-related greenhouse gas (GHG) emissions, with California aiming to cut GHG emissions by 80% below 1990 levels by 2050. Individual sectors and transportation modes are not necessarily required to meet this “80-in-50” goal, but if any one mode (such as trucks) fails to, it puts more pressure on other modes to achieve deeper cuts. Trucking is the dominant domestic freight mode in the country, and is also the fastest growing sector and consumes more energy than any other freight mode. This policy brief summarizes research that suggests that the combination of significantly improved vehicle efficiency coupled with very low-carbon fuels (electricity, hydrogen, or biofuels) can help the trucking sector reach the GHG target.View the NCST Project Webpage

The authors propose the use of ultrasonic radiation to clean the exhaust gases of internal combustion engines of the solid particles. An experimental stand and research results are presented, proving the possibility and efficiency of using the process of ultrasonic cleaning of exhaust gases due to the process of the solid particles coagulation. The authors received a corresponding patent, the efficiency of which has been proven by results of the conducted research.

The authors propose the use of ultrasonic radiation to clean the exhaust gases of internal combustion engines of the solid particles. An experimental stand and research results are presented, proving the possibility and efficiency of using the process of ultrasonic cleaning of exhaust gases due to the process of the solid particles coagulation. The authors received a corresponding patent, the efficiency of which has been proven by results of the conducted research. [ABSTRACT FROM AUTHOR]

Road transport has a significant effect on air pollution. Therefore, the article focuses on the impact of addition of "oxyhydrogen", known as HHO, on selected vehicle features. These features, on which this study is focused, include the engine power and torque, composition of the exhaust gases and fuel consumption. There was also an impact of HHO on the value of pre-ignition as well as engine cleaning observed. HHO has been obtained from the generator designed and constructed for the purposes of this article. The measurements were performed under conditions of taking electric energy needed for HHO operation from the vehicle used in the measurements and also from the other source. The measurements were performed with vehicles of different kilometres driven, different technical conditions and different fuels and they were conducted under laboratory conditions to ensure a higher accuracy of the results. The results have shown a low impact of HHO addition of 2 dm3 min−1 on concentration of particular components of the exhaust gases. With HHO added, it was measured a mild decrease in the engine power and torque. Taking electric energy needed for HHO operation from the vehicle used in the measurement has evinced more considerably than addition of HHO into the engine. [Display omitted] • HHO addition slightly reduced the engine power and torque. • Taking electric energy for the HHO generator to be driven reduced the power on the wheels. • The fuel consumption at the idling speed with HHO decreased by 10%. • Taking electric energy for the HHO generator to be driven increased the fuel consumption by 20%. • HHO in the amount of 2 dm3 min−1 is considered very low for a common vehicle. [ABSTRACT FROM AUTHOR]

The energy transition from fossil fuels to renewable fuels is constantly developing and implementing. It is the subject of worldwide research, seeking to curb climate change and the negative effects of pollution. An economic sector worldwide that generates a large amount of pollutants is the transport sector, which only uses fossil fuels. Accordingly, it is necessary to test renewable alternatives that reduce the pollution caused by the sector, trying to use the current automotive fleet. The purpose of this paper is to show the effects of the direct injection of hydrogen gas obtained using an alkaline electrolysis system in a single-cylinder internal combustion engine operated with Diesel fuel, managing to study the effects of hydrogen injection on the different engine parameters such as fuel consumption, rpm, torque, temperature, and exhaust gas analysis, performing a statistical analysis that allows determining the input variables that most influence the decrease in polluting gases CO and CO2 and the variation in fuel consumption in addition to engine performance. [ABSTRACT FROM AUTHOR]

Unfortunately, most of the technologies applied and currently used by mankind, to a lesser or greater degree, negatively influence and lead to the degradation and degeneration of the planetary ecosystem, with rail transport being no exception. The railways, together with the positive influence on the economic development of the regions in which they were built, have caused irreparable damage to the environment. They destroyed natural landscapes, led to the death and reduction of wildlife populations, polluted the air and created an unbearable noise. The pollution of the environment by the use of railway transport is also present for the Republic of Moldova. The article describes the main components of the impact of railway transport on the environment: pollutants, electromagnetic fields and rolling stock noise.

The use of alternative types of motor fuel contributes to the improvement of the economic and environmental situation in open-pit mining. An analysis of the development of opencast mining in Russia indicates constant shift to the remote northern territories. In the cost of mining, the share of transport works is 40–50%, and as the mining operations go deeper for every 100 m, the cost of transporting the rock mass by tipper trucks increases by 20–30%. With an increase in the depth of the quarry, the natural ventilation of the working area deteriorates, which leads to the accumulation of exhaust gases of diesel engines in the quarry. This affects the health of miners and the economy of the enterprise, as it entails the need to stop the quarry. Currently, the global engine industry is considering the use of natural gas as a motor fuel instead of diesel fuel. The specificity of the northern regions is such that fuel must be delivered a year in advance during the navigation period, which increases its price, while gas fields are located directly in Yakutia. The cost of production of liquid natural gas (LNG) in the regions of its consumption as a motor fuel is much lower than the cost of delivery of diesel fuel. Production can be organized directly at the gas fields in Western Yakutia. LNG plants are compact and highly reliable. Tests of Cat 789C, Komatsu 830 and 930 mining trucks in gas-diesel mode showed that the efficiency and performance of the gas engine were comparable to the efficiency of a diesel engine. Diesel fuel saving was 80%, while exhaust emissions were reduced by 25%, that improve the environmental situation. Converting of tipper trucks to LNG will reduce the gas pollution of quarries and noise by 2-3 times, increase the efficiency and competitiveness of the enterprise by reducing the costs of fuel, transporting rock mass and environmental fines.

The use of diesel engine powered equipment in underground mines across the globe has been increased considerably in the recent past to enhance the productivity and safety standards. However, the extensive use of diesel engine powered equipment caused severe health hazards because of the exposure to diesel particulate matter (DPM) and toxic gases discharged from the exhausts of these equipment. NIOH and IARC, USA, reported diesel exhausts including DPM are suspected as human carcinogen. The number of diesel equipment deployed in Indian underground mine has also increased exponentially, which resulted into significant level of DPM exposure. There have not been any comprehensive study on the exposure of DPM as well as any stipulation in the current mine safety legislation in India so far except a guideline from DGMS. The concentration of DPM depends upon many factors such as ventilation, engine designs, maintenance, types of fuel, condition of roadways, exhaust treatment arrangements etc. In the present study, field investigations were accomplished in the three underground metalliferous mines. Different parameters like quantity of air, power and life of engine and gradient of roadways were taken as independent variables to predict the concentration of DPM. Multivariate regression analysis was carried out for establishing the relation between DPM and these independent parameters, and a significant empirical equation has been derived. Thereafter, DPM values were measured by Airtec DPM monitoring instrument and the values predicted from the multivariate regression model and measured values from the instrument were validated through chi square test. [ABSTRACT FROM AUTHOR]