Structural Properties of Baked Clay Bricks Fired with Alternate Fuels

Coal is used as a traditional fuel for firing of clay bricks in kilns. The cost of coal is high and is increasing continuously. This paper describes the effect of alternate fuels on compressive strength, water absorption and density of fired clay bricks. The alternate fuels used in this study were 1) rapeseed husk (Type I), 2) combination of sugarcane-bagasse, rice husk and used clothes (Type II) and 3) coal (Type III). The results show that compressive strength of bricks fired using Type I and Type II fuels was decreased to 11% and 7%, respectively, compared to those fired with coal. However, the values of water absorption and density of bricks fired with Type I and Type II fuels were almost same as exhibited by those baked with coal. This study shows that a saving of 25%, and 18% could be achieved when the bricks were fired using Type I and Type II fuels, respectively, compared to those fired with coal.

Decarbonizing in Maritime Transportation: Challenges and Opportunities

As global warming caused by greenhouse gases grows (GHGs) into a global environmental threat, carbon dioxide emissions are drawing increasing attention in these years. Among all emission sources, transportation is a major contributor to climate change because of its high dependence on fossil fuels. The International Maritime Organization (IMO) has therefore been promoting the reduction of fuel usage and carbon emissions for container ships by such measures as improving shipping route selection, shipping speed optimization, and constructing clean energy propulsion systems. In this paper, a review of the impact of carbon dioxide emissions on climate change is presented;the current situations of carbon dioxide emissions, decarbonizing methods, IMO regulations, and possible future directions of decarbonizing in the maritime transportation industry are also discussed. Based on the result, it is found that in the case that non intelligent ships still occupy the vast majority of operating ships, the use of new energy as the main propulsion fuel has the defects of high renewal cost and long effective period. It is more likely to achieve energy conservation and emission reduction in the shipping industry in a short period of time by using intelligent means and artificial intelligence to assist ship operation. .

Investigation of performance and emission characteristics of waste cooking oil as biodiesel in a diesel engine

Biodiesel is one of the most popular prospective alternative fuels and can be obtained from a variety of sources. Waste frying oil is one such source along with the various raw vegetable oils. However, some specific technical treatments are required to improve certain fuel properties such as viscosity and calorific value of the biodiesel being obtained from waste cooking oil methyl ester （WCOME）. Various treatments are applied depending on the source and therefore the composition of the cooking oil. This research investigated the performance of WCOME as an alternative biofuel in a four-stroke direct injection diesel engine. An 8-mode test was undertaken with diesel fuel and five WCOME blends. The best compromise blend in terms of performance and emissions was identified. Results showed that energy utilization factors of the blends were similar within the range of the operational parameters （speed, load and WCOME content）. Increasing biodiesel content produced slightly more smoke and NOx for a great majority of test points, while the CO and THC emissions were lower.

The trajectory of hybrid and hydrogen technologies in North American heavy haul operations

The central aim of this paper is to provide an upto-date snapshot of hybrid and hydrogen technology-related developments and activities in the North American heavy haul railway setting,placed in the context of the transportation industry more broadly.An overview of relevant alternative propulsion technologies is provided,including a discussion of applicability to the transportation sector in general and heavy haul freight rail specifically.This is followed by a discussion of current developments and research in alternative and blended fuels,discussed again in both general and specific settings.Key factors and technical considerations for heavy haul applications are reviewed,followed by a discussion of non-technical and human factors that motivate a move toward clean energy in North American Heavy Haul systems.Finally,current project activities are described to provide a clear understanding of both the status and trajectory of hybrid and hydrogen technologies in the established context.

Measurements of Laminar Burning Velocities of Alternative Fuels:Application in Transport and Aerospace

The laminar burning velocity belongs to the fundamental combustion properties of fuels being a measure for their heat release,flame length,as well as reactivity and combustion stability,and thus,may impact the design of burners and combustion chambers.Also,these experimental data are needed for the validation and optimization within the construction and development of detailed chemical kinetic reaction mechanisms.Within this study,an overview of the different applications of fuel characterization regarding the specific area of interest(road transport,aviation,and aerospace)will be given.Depending on the application,effects of different molecular characteristics on the laminar burning velocity are evaluated:the presence of oxygen atoms and the grade of branching in a specific fuel molecule as well as the difference in the type of a chemical bond,here,single and double bonds.Examples of alternative fuels being discussed in the present study are:(Ⅰ)oxymethylene ether(OMEn)in the field of road transport;(Ⅱ)a paraffinic Alcohol-to-Jet fuel as sustainable aviation fuel;and(Ⅲ)mixtures of ethane or ethene with nitrous oxide as green propellants for rocket propulsion applications.

Supercritical thermophysical properties prediction of multi-component hydrocarbon fuels based on artificial neural network models

A good understanding of the thermophysical properties of hydrocarbon fuels at supercritical pressure is important to research on experiment and numerical simulation of fuel supercritical spray.Experimental measurements are difficult to conduct directly because of the extremely high pressure and high temperature.In this study,back propagation(BP)neural network,BP optimized by mind evolution algorithm(MEA-BP)and BP neural network optimized by genetic algorithm(GA-BP)are established to determine the nonlinear temperature-dependent thermophysical properties of density,viscosity,and isobaric specific heat(C_(2))of hydrocarbon fuels at supercritical pressure.Meanwhile,approximate formulas for these properties prediction are primarily proposed using polynomial fitting.In this paper,models that can predict three types of physical properties of three kinds of hydrocarbon fuels and their mixtures in a wide temperature range under supercritical pressure are established.In the prediction of density and C_(2),BP neural network has a good prediction effect.The results show that the MAPE is lower than 2%in the prediction of density and C_(2),but the MAPE of viscosity prediction is slightly higher than 5%using BP.Furthermore,MEA and GA are used to optimize the prediction of viscosity.The optimization effect and computation of the MEA is better than that of GA because MEA does not have the local optimization and prematurity problems.The present work offers an efficient tool to predict the thermophysical properties of hydrocarbon fuels over a wide range of temperatures under supercritical pressure which can be easily extended to other fuels of interest.It will be beneficial to the experiment and numerical simulation studies of supercritical sprays.

Comparative Assessment of Low-Concentration Ethanol and Waste Fish Oil Biodiesel Blends on Emission Reduction and Performance Improvement in Variable Compression Ratio Engine

The costs of conventional fuels are rising on a daily basis as a result of technical limits,a misallocation of resources between demand and supply,and a shortage of conventional fuel.The use of crude oil contributes to increased environmental contamination,and as a result,there is a pressing need to investigate alternate fuel sources for car applications.Biodiesel is a renewable fuel that is derived chemically by reacting with the sources of biodiesel.The present research is based on analyzing the effect of fish oil biodiesel-ethanol blend in variable compression engine for variable compression ratio(VCR).The processed fish oil was procured and subjected to a transesterification process to convert fatty acids into methyl esters.The obtained methyl esters(biodiesel)were blended with ethanol and diesel to obtain a ternary blend.The ternary blend was tested for its stability,and a stable blend was obtained and tested in VCR engines for its performance,combustion,and emission characteristics.In the second phase,experiments are conducted in the diesel engine by fueling the fish oil methyl ester and ethanol blended with diesel fuel in the concentration of 92.5 vol%of Diesel+7.5 vol%of Fish oil+1.25vol%ethanol,92.5 vol%of Diesel+7.5 vol%of Fish oil+5 vol%ethanol,87.5 vol%of Diesel+12.5 vol%of Fish oil+1.25 vol%ethanol,87.5 vol%of Diesel+12.5 vol%of Fish oil+5 vol%ethanol,82.5 vol%of Diesel+17.5vol%of Fish oil+1.25 vol%ethanol,82.5 vol%of Diesel+17.5 vol%of Fish oil+5 vol%ethanol to find out the performance parameters and emissions.Because the alternative fuel performs better in terms of engine performance and pollution management,the percentage chosen is considered the best mix.The results showed that the use of a lower concentration of ethanol in the fish oil biodiesel blend improved the engine thermal efficiency by 5.23%at a higher compression ratio.Similarly,the engine operated with a higher compression ratio reduced the formation of HC and CO emissions,whereas the NOxand CO_(2)emissions increased with an increased proportion of biodiesel in diesel and ethanol blends.

Dynamic quantitative risk assessment of LNG bunkering SIMOPs based on Bayesian network

Liquified natural gas(LNG)bunkering simultaneous operations(SIMOPs)refers to the operations(such as cargo operations,port activities and ship maintenance)occurring around LNG bunkering.SIMOPs pose new risks to LNG bunkering,because the operations are dynamically interlocked in which the occurrence probabilities of potential consequences change at different times due to commencement or completion of specific SIMOP events.However,traditional static risk assessment approaches are not able to take the dynamic nature of these new risks into account.This article proposes a dynamic quantitative risk as-sessment(DQRA)methodology based on the Bayesian network(BN)to develop better understanding of dynamic risks of LNG bunkering SIMOPs.The methodology is demonstrated and evaluated through a truck-to-ship LNG bunkering case study.The results and discussion of the case study validate the utility of the proposed methodology and demonstrate that BNs are efficient in performing the probability calcu-lations and are flexible in conducting causal diagnosis.The main innovation of this work is realizing the quantification of risks at different times,which reflects the most essential time-changing characteristics of risks associated with LNG bunkering SIMOPs.

Bioenergy recovery from landfill gas:A case study in China

Landfill gas(LFG)utilization which means a synergy between environmental protection and bioenergy recovery was investigated in this study.Pressure swing adsorption technology was used in LFG purification,and laboratory experiment,pilot-scale test,and on-site demonstration were carried out in Shenzhen,China.In the laboratory experiment,A-type carbon molecular sieve was selected as the adsorbent by comparison of several other adsorbents.The optimal adsorption pressure and adsorption time were 0.25 MPa and 2 min,respectively,under which the product generation rate was 4.5 m^(3)/h and the methane concentration was above 90%.The process and optimization of the pilot-scale test were also reported in the paper.The product gas was of high quality compared with the National Standard of Compressed Natural Gas as Vehicle Fuel(GB18047-2000),when the air concentration in feed gas was under 10.96%.The demonstration project was composed of a collection system,production system,and utilization system.The drive performance,environmental protection performance,and economic feasibility of the product gas—as alternative fuel in passenger car,truck,and bulldozer—were tested,showing the feasibility technology for LFG utilization.

Performance analysis of karanja and kusum oils as alternative bio-diesel fuel in diesel engine

Scarcity of conventional petroleum resources has promoted research in alternative fuels for internal combustion engines.Among various possible options,fuels derived from triglycerides(vegetable oils/animal fats)are promising for the substitution of fossil diesel fuel.Vegetable oils poses some characteristics like durability,high viscosity and low volatility compared to mineral diesel fuel.In the present work,experiments were designed to study the effect of reducing kusum and karanja oil’s viscosity by preheating the fuel,using a shell and tube heat exchanger.The acquired engine data were analyzed for various parameters such as brake thermal efficiency,brake specific energy consumption(BSEC),emission of exhaust gases like CO,CO_(2),HC and NO_(x).In operation,the engine performance with kusum and karanja oil(preheated),was found to be very close to that of diesel.The preheated oil's performances were found to be slightly inferior in efficiency due to low heating value.The performance of karanja oil was found better than kusum oil in all respects.

A progress review of practical soot modelling development in diesel engine combustion

Great efforts have been made over the last few decades in understanding of the mechanisms and phenomenology of soot formation and burnout in combustion systems.In this paper,theoretical advances in modelling soot formation and oxidation under engine circumstance are surveyed based on the published works,particularly focus on the practical soot modelling coupled with engine computational fluid dynamics(CFD)numerical studies.The types of soot models can be divided up into three main groups:empirical,semi-empirical and detailed soot model.With the development of computing technology and increasingly comprehensive soot fundamental knowledge,the semi-empirical phenomenological soot model with major generic processes of soot formation was proposed,which is one of the most extensively investigated soot models in recent years.It is highlighted with solving mathematical equations to get soot particle number density,soot volume and mass fraction.When coupled with fuel chemistry,the detailed soot model seeks to predict soot characteristics based on molecule structure,bringing further insight of the soot evolution and transient behavior of soot-relevant species.Therefore,the sooting tendency from engine combustion fueled with alternative and oxygenated fuels are able to be further explored,which is conductive to propose new engine technologies for soot mitigation and future fuel strategy.

The viability of using gasoline-integrated biodiesel-diesel mixtures in engines as a solution to greenhouse gas emissions:a review

The implementation of alternative fuels,such as biodiesel,in engines has been shown to be a feasible strategy to control greenhouse gas(GHG)emissions.The blending of biodiesel with diesel can reduce emissions of carbon monoxide(CO)and carbon dioxide and reduce soot formation.Nonetheless,biodiesel combustion comes with low thermal efficiency,elevated emissions of nitrogen oxides(NOx)and carbon deposition issues.Recently,the addition of gasoline to diesel-biodiesel blends has been proposed to compensate for the downsides of biodiesel combustion.In the current review,the viability of using this ternary fuel blend in engines is thoroughly reviewed.The review first assesses the environmental and health issues caused by conventional fuels,mitigation schemes to control GHG emissions and alternative fuels as a decarbonizing technology.The combustion and emissions characteristics of diesel-bio-diesel-gasoline mixtures are discussed in detail.Finally,the status,challenges and prospects of applying the alternative fuel mixture in engines are appraised.This work has revealed that the mixing of gasoline with diesel-biodiesel blends brings about elongated ignition delay,increased heat release rate and in-cylinder pressure at high loads.Additionally,by adding gasoline,the combustion duration is shortened and soot,CO and unburned hydrocarbon emissions are suppressed,while NOx emissions are slightly increased.Combustion stability is found to be partially disrupted in the presence of gasoline whereas fuel economy(at medium and high loads)is improved by the addition of gasoline.To support the wider deployment and commercialization of this fuelling strategy in the transportation sector,favourable legislation and/or fiscal incentives are needed in countries around the world.This would encourage researchers,fuel producers and engine manufacturers alike to solve challenges such as biodiesel feedstock costs,fuel quality,fuel storage management and engine warranty issues.

NATURAL GAS AS AN ALTERNATIVE FUEL

Research in Early Days In early 1950s to 1960s, China began to study natural gas as an alternative fuel according to the State Science & Technology Commission’s requirment of widely utilizing natural gas. A testing station for natural gas vehicles was established in Sichuan province