Post Combustion Research Articles

Experimental and COSMO-RS analysis of CO2 solubility in novel aqueous blends of 1-butyl-3-methyl-imidazolium tetrafluoroborate activated by 2-aminoethyl piperazine and bis(3-aminopropyl) amine for post combustion carbon capture

Analysis of available technologies and exploration of new ones are an integral approach for studying the efficient separation of carbon dioxide (CO2) from large point sources. Anew proposed aqueous solvent blends of 1-butyl-3-methyl-imidazolium tetrafluoroborate ([bmim] [BF4]) and 1-(2-aminoethyl) piperazine (AEP) /bis (3-aminopropyl) amine (APA) are studied theoretically using COSMO-RS and experimentally for CO2 capture application. The molecules are studied for describing relationship amid sigma-potential and sigma-surface with CO2 solubility. Important thermodynamic properties such as vapor pressure, Henry’s constant have been evaluated using COSMO-RS method and compared with available experimentally obtained values. Essential binary interaction parameters of vapor liquid equilibrium of the solvents are estimated using NRTL and UNIQUAC 2 models. The work considers the measurements and modelling of CO2 solubility in conferred solvents over (303.15˗323.15) K and (1−244) kPa, respectively. The investigational CO2 solubility data are associated with feed forward neural network model. Thermophysical properties of viscosity, and density have also been measured and modelled employing recognised models.

Water consumption of the integration of coal-fired power plant with CO2 post combustion system with different cooling methods

CO2 capture is one of the most effective methods to reduce CO2 emissions. Integration with CO2 capture system will cause an energy penalty for the coal-fired power plant which has been extensively studied, while it also increases the water consumption that has less focus. This paper analyzes the water consumption of a coal-fired power plant integrated with CO2 capture system under three operation modes which is (1) power reduction mode, (2) constant total output power, and constant CO2 capture quantity, (3) constant total output power, and constant CO2 capture rate. Regardless of the cooling method, the thermal efficiency of the integration system is the highest when the output power is constant, and the carbon capture amount is constant. Combined with coal consumption, water consumption, output power, and CO2 emissions, the system operating in a mode with constant output power and a constant carbon capture rate is further analyzed. When the temperature rises from 130 °C to 160 °C, the total water consumption increased from 1024.71m3/h to 1069.66 m3/h. When the heat duty rises from 2.0 MJ/kg CO2 to 4.0 MJ/kg CO2, the total water consumption decreases from 1081.55 m3/h to 1000.89 m3/h due to the significant reduction in water consumption in coal-fired systems. Unit water consumption has the same trend.

Study on the recycling of zeolitic imidazolate frameworks and polymer Pebax® 1657 from their mixed matrix membranes applied to CO2 capture

Mixed matrix membranes (MMMs) consisting of fillers (e.g. metal organic frameworks (MOFs)) in polymer matrix are considered as an interesting alternative for capturing post combustion CO2 towards a sustainable development. This research is focused on the recycling of MMMs made of polymer Pebax® 1657 and MOF ZIF-94. Upon MMM preparation, characterization and testing, MMMs were dissolved to recover polymer and MOFs separately. Recovered products were characterized by SEM, EDX, FTIR, TGA, XRD, DLS, mass spectrometry and N2 adsorption to compare their size, shape and other properties with those of fresh ones. Mean particle size of fresh and recycled ZIF-94 were 148 ± 44 nm and 164 ± 32 nm, respectively. Incorporation of recycled ZIF-94 in MMMs produced defect free membranes which was confirmed by SEM and gas separation measurements. These MMMs, with a 10 wt% ZIF-94 loading, were tested for the separation of the CO2/N2 mixture with a CO2 permeability of 157 ± 6.5 Barrer (with 67 % improvement compared to fresh pure polymer membrane with 94 ± 2 Barrer) and a CO2/N2 selectivity of 27.5 ± 1.4 (5 % lower than that of the fresh MMM, 29.3 ± 1.8, but 20 % higher than the corresponding to the pure polymer membrane, 23 ± 2). Demonstrating its wide feasibility, the proposed methodology was also applicable for recycling of ZIF-8 from Pebax® 1657 based MMMs.

On the phase behaviour of the CO2 + N2O4 system at low temperatures

• VLE data for CO 2 + NO 2 /N 2 O 4 at 253 to 303 K using a static-synthetic apparatus. • Experimental data compared to the Peng–Robinson (PR) with classic mixing rules. • Melting points of N 2 O 4 in CO 2 were measured. • Models used to predict the phase diagram of the binary system. Carbon dioxide capture transportation and storage is one of the technologies that can be employed to reduce CO 2 emissions from power plants. Unfortunately, in the post combustion capture process, CO 2 is not pure and contains impurities like SO 2 , NO x , N 2 , O 2 and Ar for example. In this paper, Vapour-Liquid-Equilibrium (VLE) of a binary system composed of CO 2 and N 2 O 4 /NO 2 have been investigated. The equipment used is based on the “static-synthetic” method with a variable cell to determine the bubble pressure or saturated pressure of the system. The setup was used to obtain bubble point data at four isotherms (253.43, 273.43, 293.43, 303.43) K and pressures up to 7.3 MPa. The accuracies of the measured temperature and pressure were estimated to be 0.03 K and 0.12 kPa, respectively. The Peng–Robinson equation of state (PR78 EoS) is used to represent the isothermal P, x data.

Simulation and application of post-combustion oxygen lance in a top-blown converter

ABSTRACT Flow field characteristics of conventional four-hole oxygen lance and single-flow post-combustion (PC) oxygen lance at steelmaking temperature are studied by numerical simulation, and the industrial trials are carried out in the 120 t top-blown converter to evaluate their metallurgical effects. The simulation results indicate that with the increase of ambient temperature, the potential core length of oxygen jet, jet velocity and radial width (jet diameter) increase. And the jet characteristics of PC oxygen lance are better than those of conventional lance in the radial and axial directions. The industrial trials show that, compared with the conventional lance, using the PC oxygen lance can shorten blowing time by 93 s, reduce actual oxygen consumption by 3.56 m3 t−1 and increase dephosphorization rate by 1.67%. Meanwhile, PC oxygen lance is better for slagging and solves the problem of splashing or drying caused by increasing the oxygen flow rate of the conventional lance.

Hybrid biomass and natural gas combined cycles: Energy analysis and comparison between different plant configurations

The research community has been investigating the integration of biomass into power plants to foster the energy transition to renewables and reduce the dependence on fossil fuels. The aim of the work is to evaluate the energy performance of different combined cycle configurations fueled by natural gas and lignocellulosic biomass, based on biomass gasification and direct combustion of biomass. In the former case, the plant is cofired (COF) with natural gas and syngas. In the latter, two plant configurations were compared: conventional Post-Combustion (PC) and Integrated Fired Recuperated Combined Cycles (BIFRCC), where post-combustion is used to increase the temperature of the air leaving the compressor. The capacity of the systems to integrate biomass was compared with conventional biomass-only plants. The influence of the biomass share has been studied on the main performance indicators: global and biomass efficiency; electrical power increase due to biomass addition; carbon dioxide emissions. An optimization was carried out to identify the most suitable plant configuration and the proper biomass fraction to achieve a trade-off between the need to maintain high global efficiency and high biomass integration. The BIFRCC system has proven to be the most appropriate, with a 35.3% biomass feed ratio and a 41.8% biomass efficiency, significantly higher than conventional steam plants (30% maximum efficiency).

Development of blend PEG-PES/NMP-DMF mixed matrix membrane for CO2/N2 separation

The carbon dioxide (CO2) separation technology has become a focus recently, and a developed example is the membrane technology. It is an alternative form of enhanced gas separation performance above the Robeson upper bound line resulting in the idea of mixed matrix membranes (MMMs). With attention given to membrane technologies, the MMMs were fabricated to have the most desirable gas separation performance. In this work, blend MMMs were synthesised by using two polymers, namely, poly(ether sulfone) (PES) and poly (ethylene glycol) (PEG). These polymers were dissolved in blend N-methyl-2-pyrrolidone (NMP) and dimethylformamide (DMF) solvents with the functionalised multi-walled carbon nanotubes (MWCNTs-F) fillers by using the mixing solution method. The embedding of the pristine MWCNTs and MWCNTs-F within the new synthesised MMM was then studied towards CO2/N2 separation. In addition, the optimisation of the loading of MWCNTs-F for blend MMM for CO2/N2 separation was also studied. The experimental results showed that the functionalised MWCNTs (MWCNTs-F) were a better choice at enhancing gas separation compared to the pristine MWCNTs (MWCNTs-P). Additionally, the effects of MWCNTs-F at loadings 0.01 to 0.05% were studied along with the polymer compositions for PES:PEG of 10:20, 20:20 and 30:10. Both these parameters of study affect the manner of gas separation performance in the blend MMMs. Overall, the best performing membrane showed a selectivity value of 1.01 + 0.05 for a blend MMM (MMM-0.03F) fabricated with 20 wt% of PES, 20 wt% of PEG and 0.03 wt% of MWCNTs-F. The MMM-0.03F was able to withstand a pressure of 2 bar, illustrating its mechanical strength and ability to be used in the post combustion carbon capture application industries where the flue gas pressure is at 1.01 bar.

Experimental investigation of microwave-assisted regeneration of carbon-rich aqueous solutions

Solvent-based post combustion carbon capture is the most prevalent carbon capture technology where 30wt% Monoethanolamine (MEA) is the benchmark solvent used for carbon capture with high energy consumption. Microwave (MW)-assisted carbon-rich solvent regeneration is one of the emerging technologies for CO2 stripping with lesser energy consumption and experimental study covers in these aspects. The factors and levels considered for designing L27 orthogonal array includes nominal power input (10%, 20% and 30% of 800 Watts), regeneration time (5, 15 and 25 min), solvent load (40, 60 and 80 g) and different solvents (30wt% MEA, 20wt% potassium carbonate, and 20wt% piperazine). Physicochemical properties like carbon loading, density, viscosity, surface tension, pH and temperature were tested before and after regeneration. From the experimental investigation, it has been observed that all the physiochemical properties show decreasing trend after the regeneration except pH and temperature. An optimum conditions of lower power level, longer regeneration time and lower solvent loading exhibits better solvent regeneration in the tested conditions. In addition, 20wt% piperazine has the highest regeneration efficiency of 48%. In a cyclic process, the baseline aqueous 30wt% MEA exhibits the lowest regeneration energy of 0.13 kW/mol.CO2 with 24.26% regeneration efficiency for 10% nominal power input.

CFD modelling of the off-gas system of HIsarna iron making process. Part 1: model development using detailed reaction mechanism for post-combustion of CO–H2 mixture and carbon particles

ABSTRACT The HIsarna process is a new and breakthrough smelting reduction process for hot metal (liquid iron) production from iron ores and coal directly fed into the reactor. The flue gas from the main reactor enters the off-gas system containing small amounts of H2, CO and carbon particles which need to be removed before further treatment by post combustion oxygen injection. A three-dimensional Computational Fluid Dynamics (CFD) simulation of the HIsarna off-gas system is performed and validated using a detailed reaction mechanism and kinetic data for post-combustion of a CO–H2 mixture and carbon particles. Using the validated model, a series of simulations were performed to investigate the effect of water quenching and post combustion oxygen injection. It was found that water quenching can significantly reduce the off-gas temperature. It is also possible to reduce oxygen injection during operations where inlet CO content of the off-gas system is low.

Thermo-economic and environmental performance analyses of a biomass-based carbon negative system integrating externally fired gas turbine and molten carbonate fuel cell

Biomass fueled power generation systems integrated with carbon capture has very good potential of mitigating climate change, but they usually experience low efficiency. A novel biomass gasification-based carbon negative system consisting of an externally fired gas turbine, post combustion CO2 capture employing molten carbonate fuel cell (MCFC) and waste heat recovery through steam cycle and organic Rankine cycle (ORC) is proposed and investigated in this article. Energy, exergy, economy and environmental analyses of the proposed system have been performed. Parametric investigation has been carried out and the effects of key operating parameters i.e., compressor pressure ratio, turbine inlet temperature, current density and fuel utilization factor of the fuel cell, steam pressure of the steam cycle on the overall performance of the proposed plant have been observed. The proposed plant can generate 16.21 MW of maximum power, with 50.8% of maximum energy efficiency, costing minimum levelized electricity price (LEP) of 0.097 $/kWh with 90% carbon capture. Moreover, the plant captures yearly maximum 112,400 tons of carbon dioxide which results in 16.8 million $/year environmental benefit to the society. The results also show that the present system is superior in terms of both energy and economy aspects compared to the other biomass-based carbon negative systems with post combustion carbon capture mentioned in recent literature.

Experimental Investigation on Carbon Dioxide Reduction by Using Post Combustion Carbon Capture System in a Spark-Ignition Engine

Global warming is a serious environmental concern that affects humans, wildlife, and ecosystems. Carbon dioxide reduction is the need of the hour as it a major constituent of global warming. The quantum of carbon dioxide released in the exhaust depends on the number of carbon atoms present in the fuel used. The present study investigates the reduction of engine out carbon dioxide emission. For carbon dioxide reduction post combustion capture sys- tem is used. In post combustion capture system carbon dioxide is absorbed by using absorption catalyst. In this capture system, carbon dioxide is absorbed after the combustion. Among various absorption catalyst, monoethanolamine (MEA) is used, as it can react more quickly with carbon dioxide than other absorbents. Monoethanolamine is continuously injected in the exhaust mani- fold. Empty chamber is added in the exhaust manifold for increasing the resi- dent time of the reaction of amine with carbon dioxide. MEA reacts with carbon dioxide forms ammonium carbamate. Carbamate is approved by the Environ- mental Protection Agency as an inert ingredient, used for insect and rodent control in areas where agricultural products are stored.

Effect of diesel particulate filter regeneration on fuel consumption and emissions performance under real-driving conditions

Diesel particulate filters (DPF) are widely adopted in diesel vehicles to meet the increasingly stringent emission regulations, which require continuous passive regenerations or/and periodic active regenerations to burn off the accumulated particulate matter (PM). In spite of many laboratory studies using DPF benches and engine/chassis dynamometers, there is currently a lack of investigation on DPF regeneration under real-world conditions. Therefore, this study was conducted to investigate the impact of active DPF regenerations on the fuel consumption and gaseous and particulate emissions performance of a diesel light goods vehicle under real-driving conditions by using the state-of-the-art portable emission measurement system. In total, 60 real-driving emission (RDE) tests (∼1200 km in total) were performed on the same route during the same periods of a day, to minimise the effect of uncontrollable real-world factors on the performance evaluation. The results showed that real-world active DPF regenerations occurred every 130 km for the studied vehicle. Although they did not occur frequently, DPF regenerations increased the trip-averaged fuel consumption rate by 13% on average. CO and THC emission factors tended to increase with DPF regenerations because the post combustion used to achieve the high exhaust temperature for regeneration of the filter occurred under oxygen-lean conditions. Total NOx emissions were not affected but NO2/NOx ratio was greatly reduced by DPF regeneration due to lower NO oxidation by the diesel oxidation catalyst and higher NO2 reduction by the DPF. Finally, DPF regenerations sharply increased PM emission factors by 27 times compared with a trip without DPF regeneration, resulting in significant exceedance of the emission limit.

Artificial neural network prediction of transport properties of novel MPDL-based solvents for post combustion carbon capture

Novel N-methyl-4-piperidinol (MPDL)-based solvents have been considered as high potential solvents for post combustion carbon capture, especially for power generation industry. To comprehensively investigate the CO2 absorption-regeneration performance of MPDL-based solvents, transport properties (i.e., density, viscosity, and physical CO2 diffusivity) are required. These data are reported in the literature and can be estimated by conventional predictive correlations. However, the conventional correlation is applicable for an individual solvent at various blended ratios and temperatures. Thus, artificial neural network (ANN) was then applied for prediction of the transport properties of MPDL-based solvents, including aqueous solutions of MPDL, MPDL-monoethanolamine (MEA), MPDL-2-amino-2-methyl-1-propanol (AMP), and MPDL-piperazine (PZ). Three learning algorithms of (i) Levenberg–Marquardt (LM), (ii) Bayesian Regularization (BR), and (iii) Scaled Conjugate Gradient (SCG) were applied to develop the predictive ANN models with various hidden neurons. As a result, 6 hidden neurons BR-ANN model was the most convincible single prediction platform for the three transport properties. The develop model can be very beneficial for further applications associated with the novel MPDL-based solvents.

Study and test of a post combustion chamber for a recuperative reheat Stirling machine

Stirling machines present a forthcoming potential for substituting the internal combustion engine as an auxiliary power unit in future series hybrid electric powertrains. Different Stirling thermodynamic configurations can be found in the literature. Among them, the recuperative reheat Stirling thermodynamic cycle offers high net specific work and high efficiency, resulting in reduced system's weight, size and integration complexity, as well as reduced vehicle's fuel consumption. This paper presents an experimental investigation of the impact of Stirling combustion reheat process on the system performance and emissions. For that purpose a Stirling combustion chamber was modified and a post combustion chamber was added. The new configuration of the designed combustion chamber was manufactured and tested. The effect of reheating process on pollutant emissions was evaluated by measuring the NOx emissions and compared to the fuel quantity injected in both reheat and no reheat configurations. The test results demonstrate the high importance of reheating process in decreasing the NOx emission. The obtained reduction was more than 50% in comparison to the original construction. Consequently, the recuperative reheat Stirling thermodynamic configuration was selected as the best candidate for replacing the internal combustion engine.

Prediction of CO2 solubility in potential blends of ionic liquids with Alkanolamines using statistical non-rigorous and ANN based modeling: A comprehensive simulation study for post combustion CO2 capture

Equilibrium CO2 solubility data plays a pivotal role in the process design of the post-combustion CO2 capture Unit. In the current study, statistical non-rigorous models are developed to predict the solubility of carbon dioxide (CO2) in different aqueous blends of ionic liquids (ILs) and blends of ILs with alkanolamines, ethanol, etc. These correlations are utilized to estimate the liquid phase CO2 loading as a function of CO2 partial pressure at different temperature conditions. The correlations can predict CO2 solubility in the liquid phase of different (ILs + alkanolamine + water/ethanol) in the temperature and CO2 partial pressure range of (298–353) K and (50–6200) kPa respectively. The CO2 mole fraction in the liquid phase pertaining to 19 different solvent formulations is considered in the range of (0–0.487). It has been found that there is a good agreement between the results of the proposed models and reported experimental data of CO2 solubility. In addition to this, the predictability of artificial neural network (ANN) for CO2 solubility is also tested for 22 systems of ionic liquid blends with amines. The main advantages associated with these proposed models are their underlying simplicity and minimal input data, namely temperature and pressure.

Mathematical model for the forced oxygen blowing decarburization process of ultra-low carbon steel during RH treatment

A new mathematical model for the RH forced oxygen blowing decarburization process which takes the influence of post combustion on decarburization into account is established. Decarburization reactions are considered to take place at four reaction sites. The simulated results of carbon and oxygen contents show relatively good agreement with the experimental data under different oxygen flow rates. At the rapid decarburization stage including the O2 blowing process, 66.1% of the total decarburization amount is removed. By using the forced oxygen blowing decarburization process, the decarburization rate in the bulk steel is improved most significantly. Additionally, the effects of oxygen flow rates on carbon, oxygen and total decarburization rate are evaluated in detail. At 1500 m3 · h−1, the oxygen content is adequate to completely remove carbon of molten steel in the vacuum vessel during the O2 blowing. Combining with the analysis of oxygen flow rates on the decarburization rate at each site, 1500 m3 · h−1 is chosen as the critical oxygen flow rate to achieve the best decarburization performance. The influences of other parameters including initial carbon and oxygen contents and oxygen utilization rate on decarburization are also investigated.

Chemical kinetics modelling for the effect of chimney on diffusion flame in carbon nanotubes synthesis

Hydrocarbon flame syntheses of carbon nanotubes (CNTs) on various metals substrates have been reported in literature, but existing methods are limited to usage of high melting temperature metals substrate due to excessive temperature in conventional diffusion flame burner. To address this limitation, high thermal conductivity chimney is innovatively incorporated into the diffusion burner to control flame temperature. Hence, the aim of this study is to investigate the effect of chimney application on the interaction behaviour between flame temperature profile and concentration of post combustion species distribution of diffusion flame. In this study, Computational Fluids Dynamics (CFD) – Chemical Kinetics (Chemkin) coupling method is used to simulate the flow and transport behaviour of laminar methane-air mixture in combustion environment. Kinetics mechanism is imported into species transport model of Chemkin simulator to further determine the reaction between combustion species and temperature profile of the mixture. Heat transfer models are then integrated into simulation to investigate the cooling effect of chimney during the combustion of methane-air mixture. This numerical simulation study provides insights on effects of chimney application towards cooling, species concentration, flame temperature and paving path for controlling the growth of CNT on low melting temperature metal substrate. Numerical models show improvement in temperature controls, increase in gas species concentration and in surface area that is favourable for growth of CNTs.

Investigation of equilibrium CO2 solubility in 35 wt% aqueous 1-(2-aminoethyl) piperazine (AEP) and performance study over monoethanolamine for CO2 absorption

The present study investigates the CO2 absorption capacity of 1-2-(aminoethyl)piperazine (AEP) as a potential solvent for post combustion CO2 capture. The CO2 absorption performance has been evaluated in terms of Equilibrium CO2 solubility at varied temperature and pressure range. The CO2 solubility measurement was conducted using high pressure stirred autoclave reactor within the temperature and Pressure range of (308.15–328.15) and (2–200) kPa respectively. The equilibrium CO2 solubility data are further correlated using semi-empirical model and equilibrium based Modified Kent-Eisenberg model which shows a better agreement with the generated experimental data. In addition to this, a comprehensive parametric study was also carried out in Aspen-Plus Platform to evaluate the performance of proposed solvent over conventional solvent monoethanolamine (MEA). Influence of various important operating parameters such as flow rates of solvent and Gas medium, amine concentration, solvent inlet temperature and (L/G) ratio on the % CO2 removal was studied.

Gas sorption and selectivity study of N,N,N′,N′-tetraphenyl-1,4-phenylenediamine based microporous hyper-crosslinked polymers

One of the most important parameters to design porous polymeric materials for gas storage and separation is to discover appropriate linker. Determining the effect of linker, in fixed core, over the selectivity and adsorption has been great challenge. Here, three different N,N,N′,N′-tetraphenyl-1,4-phenylenediamines (TPPA) based microporous hyper-crosslinked polymers synthesized by the Friedel-Craft reactions. Hypercrosslinked polymer, TPPA-DMM, was obtained from dimethoxymethane (DMM) and hypercrosslinked-covalent polymer, TPPA-DMB, from dimethoxybenzene (DMB) in presence of FeCl3. TPPA-CC, covalent triazine polymer was synthesized from cyanuric chloride (CC) via AlCl3 as the catalyst. After the careful characterization of these microporous structures with different analytical and spectral analyses, the gas uptake (for CO2, CH4, O2, CO, and H2) and selectivity properties (for CO2/N2, CO2/O2, for CO2/CO and CO2/CH4) were comparatively investigated at pipe gas temperatures and up to 1 bar. The high BET specific surface areas ranging from 742 to 883 m2/g with ultramicropore characters (0.53–0.58 nm), high chemical stability in different solvents even in concentrated acid and thermal stability (up to 450 °C) promised that these materials can be used in pipe gas processes. By changing the linkers on the core, materials have high gas uptake properties reaching 12.98 wt% for CO2 uptake, 1.57 wt% for CH4 uptake, 1.06 wt% for CO uptake at 1 bar/273 K and also reaching 1.28 wt% for H2 uptake at 1 bar/77 K. In addition, the unusual N2 phobic character down to 0.2 wt% and O2 phobic character down to 0.3 wt% were observed. The selectivity was calculated by using the ideal adsorbed solution theory (IAST). The selectivities were found reaching 80.4 for CO2/N2, 8.5 for CO2/CH4, 30.1 for CO2/CO and 39.1 for CO2/O2. These calculations show that the obtained polymers can be used in post combustion processes which needs high pressures and temperatures. The selectivities of the synthesized materials for the gas sorptions changed drastically by switching the linkers in all three materials. Interestingly, IAST calculations from single to dual gas, in the different ratios, showed that selectivities were almost the same for each polymer within itself at same temperature. To date, these are the first reported discoveries for the porous organic polymers in the literature.

Numerical investigation on the impact of multiple injection strategies and spray included angles on combustion and emissions in a marine diesel engine

The computational fluid dynamical software AVL-FIRE code was used for investigating the impact of multiply injection strategies and spray included angles on combustion and emissions in a marine diesel engine. The fuel injection parameters of spray included angle and pilot injection timing with pilot-main injection, as well as post injection ratio and post injection duration angle with pilot-main-post injection, were all investigated and optimized. The results indicate that retarding pilot injection timing with pilot-main injection declines high temperature region, resulting in a notable reduction in NOx emissions. Since fuel evaporation and burn are hampered by long spray penetration due to low temperature and pressure with pilot injection, a suitable spray included angle are used to offer more efficient air-fuel mixing process. A wider spray included angle simultaneously reduces soot emission and indicated specific fuel consumption (ISFC). Post injection fuel exerts impact on combustion process by causing a great disturbance to flow field during post combustion. Increasing post injection ratio from 4% to 10% at a small post injection duration angle great emission performance is achieved by simultaneous reduction in NOx and soot emissions while only using a slight consumption of ISFC. To summarize, the defeat of traditional NOx-soot trade-off occurs as both NOx and soot emissions are decreased with optimized multiple injection strategy and spray included angle. Particularly, there are respectively four cases with pilot-main injection and two cases with pilot-main-post injection, that achieve simultaneous reduction in NOx emissions, soot emission, and ISFC, compared to the prototype.