Post Combustion Research Articles

Multi-objective optimization of post combustion CO2 capture using methyldiethanolamine (MDEA) and piperazine (PZ) bi-solvent

Global warming is becoming a critical issue in 21st century which is mainly due to the growing rate of greenhouse gas emissions. This is mostly due to the large amount of CO2 emission from power generation activity using fossil fuels. One of the main methods of fighting global warming and reducing CO2 emission into atmosphere is to perform carbon capture, sequestration and utilization. Carbon capture can be performed through different ways, in which post combustion CO2 capture (PCC) has been developed and both economic and technically wise is in state of art. One of the disadvantages of PCC is its high efficiency penalty due to energy consumption in the reboiler for solvent regeneration. Many efforts have been done to reduce the consumption of energy in the reboiler via different strategies including process parameters optimization, solvent development and novel process configuration. This investigation used different blends of PZ and MDEA as solvent and process parameters optimization via evolutionary algorithm and multi-objective optimization. The optimization was performed on a conventional process flow diagram. CO2 capture efficiency and reboiler heat duty were used as the objective functions and main decision variables are solvent flowrate and MDEA/PZ concentration. Flue gas CO2 capture of 90, 91, 92, 93, and 94% corresponded to regeneration energy consumption of 2.68, 2.71, 2.72, 2.75, and 2.76 Eregen/tCO2; respectively. These optimized values showed a higher energy efficiency compared to MEA and MDEA/PZ in conventional process configuration.

Use of frothers to improve the absorption efficiency of dilute sodium carbonate slurry for post combustion CO2 capture

With current environmental regulations, CO2 capture is very crucial for the survival of coal-fired power plants in the near future. In this work, the CO2 absorption performances of Na2CO3, NaOH, Monoethanolamine (MEA) and frother-enhanced Na2CO3 were investigated experimentally in a pilot scale gas−liquid countercurrent column. A surfactant was added to the sodium carbonate solution in order to increase the surface area available for CO2 transport within the packed bed. This increased the CO2 capture efficiency of dilute sodium carbonate slurry from 55.6% to 99.9%, before reaching saturation. The main intent of this study is to compare the efficiency of frothers and conventional reagents for chemical absorption CO2 capture. We analyzed the advantages and disadvantages of each of these reagents along with frother-enhanced sodium carbonate slurry.

Investigating the Potential for Increased Energy Utilisation and Reduced CO2 Emissions at Mo Industrial Park

The potential for increased energy utilisation and reduced carbon footprint has been investigated for the industrial park Mo Industri Park (MIP), located at Mo i Rana, Norway. Process data has been gathered to quantify the energy flows between industrial clients. The energy flows have been visualised quantitatively in Sankey diagrams, while the quality of the available energy is presented in the form of a grand composite curve. High temperature flue gas from ferrosilicon (FeSi) production at Elkem Rana represent the largest heat source available for utilisation. A theoretical assessment of potential applications for this energy is presented and includes: (1) electricity production; (2) local biocarbon production, where surplus heat is utilised for drying of wood chips; (3) post combustion carbon capture, where surplus heat is utilised for solvent regeneration. The results indicate that increasing the current energy recovery from 400 GWh to >640 GWh is realistic. The increase in energy recovery can be used for reducing the carbon footprint of the industrial park. Investment in a common utility network for surplus heat may lower the threshold for establishing other energy clients at MIP. These are possibilities which may be investigated in more detail in future work.

Sustainable Trend in Mitigating Fuel Emissions and Load Performance of Internal Combustion Engine Empirical Research

As technology strives with increase in energy demand, there is need of adopting reliable techniques towards maintaining green environment without affecting production. Knowing fossil and biomaterial feedstock with different percentages of NOx emissions generation. This research reviews the effective ways of reducing the various pollutants (NOx, CO, HC and smoke) emissions from different fuel types (petroleum and biodiesel). This centered on some factors on high generation of NOx emissions from biofuel and fossil which include flame adiabatic temperature, molecular structure of the bio-material (biofuel)and fossil, load conditions and ignition delay time. The paper further stated the adequate methods for reduction of NOx, HC, smoke and others for both in pre and post combustion approaches. However, the observed results from the adopted technologies indicates that EGR introduced, reduced the NOx emissions at about 5-25% EGR rate when used with bio-fueled engine. This is achievable via controlling the combustion peak temperature and oxygen content, also shows significant drop in CO and HC emissions. Finally, with this techniques and modifications, the fuel emissions will be greatly minimized for better environment for operational activities.

Pebax® 2533/Graphene Oxide Nanocomposite Membranes for Carbon Capture.

In this work, the behavior of new GO-based mixed matrix membranes was tested in view of their use as CO2-selective membrane in post combustion carbon capture applications. In particular, the new materials were obtained by mixing of Pebax® 2533 copolymer with different types of graphene oxide (GO). Pebax® 2533 has indeed lower selectivity, but higher permeability than Pebax® 1657, which is more commonly used for membranes, and it could therefore benefit from the addition of GO, which is endowed with very high selectivity of CO2 with respect to nitrogen. The mixed matrix membranes were obtained by adding different amounts of GO, from 0.02 to 1% by weight, to the commercial block copolymers. Porous graphene oxide (PGO) and GO functionalized with polyetheramine (PEAGO) were also considered in composites produced with similar procedure, with a loading of 0.02%wt. The obtained films were then characterized by using SEM, DSC, XPS analysis and permeability experiments. In particular, permeation tests with pure CO2 and N2 at 35°C and 1 bar of upstream pressure were conducted for the different materials to evaluate their separation performance. It has been discovered that adding these GO-based nanofillers to Pebax® 2533 matrix does not improve the ideal selectivity of the material, but it allows to increase CO2 permeability when a low filler content, not higher than 0.02 wt%, is considered. Among the different types of GO, then, porous GO seems the most promising as it shows CO2 permeability in the order of 400 barrer (with an increase of about 10% with respect to the unloaded block copolymer), obtained without reducing the CO2/N2 selectivity of the materials, which remained in the order of 25.

Experimental Performance Assessment of Layered Thermobaric Explosive in an Explosion Chamber

AbstractExplosion experiments of cyclotetramethylene tetranitramine (HMX) based layered thermobaric explosive (TBX) were carried out in an explosion chamber. The layered TBX was prepared by combination of both press and cast procedures, and the shock overpressure, quasi‐static pressure (QSP), heat flux, and oxygen concentration data were obtained. The results show that the corresponding parameters of TBX are significantly larger compared with TNT, which indicates obvious thermobaric effects of TBX. To correctly evaluate the performance of the layered TBX, the TNT equivalent model based on the overpressure and QSP of TBX was established, which could reflect the two stages of detonation and post combustion effects of the TBX.

System integration for coal-fired power plant with post combustion CO2 capture: Comparative study for different solid dry sorbents

For post-combustion CO2 capture technology, integration of CO2 capture will lead to considerable efficiency penalty of the power plant. This paper quantitatively compares the thermal performance of the integrated system with CO2 capture by three different solid sorbents, namely the solid amine Pentaethylenehexamine (PEHA), Na2CO3 and K2CO3. Due to different regeneration temperature, the retrofit schemes of the integrated system differ for three different sorbents. The back-pressure turbines are used to retrieve the surplus energy of the extracted steam for PEHA and Na2CO3, whereas multi-stage compressors are used to increase the extracted parameters for K2CO3. The thermodynamic and exergy analysis results show that the thermal consumption of regeneration and the regeneration temperature are the two key parameters influencing the efficiency penalty. Efficiency penalty is increased by 1.4% per 1.0 GJ/tCO2 increment and 0.67% per 10 °C temperature increment of regeneration. Due to a low thermal consumption of regeneration and regeneration temperature, the solid amine sorbent (PEHA) performs the best out of the three solid sorbents with the lowest efficiency penalty of 9.59%. Besides, comparison with monoethanolamine (MEA) based solvent systems (efficiency penalty of 9.66%–13.73%) shows that, the solid amine sorbent (PEHA) exhibits promising competitiveness in terms of energy consumption.

Elucidating the performance of (N-(3-aminopropyl)-1, 3-propanediamine) activated (1- dimethylamino-2-propanol) as a novel amine formulation for post combustion carbon dioxide capture

The exploration of energy-efficient amine solvents for CO2 removal from fluegas streams has been adopted as a key strategy for the wide implementation of CO2 capture technology in fossil fuel-based power plants for post-combustion CO2 capture. The current study entails an insight into the CO2 absorption performance of a novel aqueous amine blend of N-(3-aminopropyl)-1,3-propanediamine (APDA) and 1-dimethylamino-2-propanol (1DMAP) with special emphasis to the investigation of CO2 solubility at equilibrium state. In order to investigate the effect of promoter addition, the concentration of APDA has been gradually increased from 0.02 w to 0.10 w in the mixed solvent blend. The generated solubility data are correlated using two different modeling approaches viz., equilibrium based modified form of Kent-Eisenberg (KE) thermodynamic model and feed-forward neural network model. The model prediction is further extended to estimate pH and the overall speciation profile of all the molecular as well as ionic species prevailing in the solvent system. The CO2 solubility data are also analyzed in view of estimating the heat duty requirement for the absorption process. The heat of absorption of CO2 in aqueous (APDA + 1DMAP) blend has been calculated using theGibbs-Helmholtz equation. Along with solubility measurement, important thermophysical properties such as density and viscosity of the aqueous amine solution are also measured and correlated using established Redlich-Kister and Grunberg Nissan models.

Efficient decentralized control of the post combustion CO2 capture plant for flexible operation against influent flue gas disturbances

The increase and accumulation of the CO2 greenhouse gases emissions raises the society’s concern and has become a stringent environmental problem. Flue gases released by thermal power plants are important contributors to these emissions and the scientific research community firmly engaged to find efficient carbon capture solutions. The post-combustion CO2 capture using amines is a leading technology, striving to continuously increase its efficiency and reduce its associated costs. Achieving these aims is progressively dependent on the flexibility of the carbon capture plant to cope with changes in its operation due to the power plant variable loading. Control systems have the potential and are responsible for fulfilling this task. The paper presents the design and assesses the performance of a 4 × 4 proposed decentralized control system intended to reject the most challenging CO2 influent flow rate and concentration disturbances emerging from the power plant, but also to satisfy the setpoint tracking ability demand. A previously developed complex model for the absorber and desorber columns was extended with a buffer tank and a cross heat exchanger meant to reduce the interacting effects between the columns and support the control system efficiency. The model was then scaled-up with the aim of building a novel simulation tool for an industrial scale carbon capture plant. Carbon Capture rate and Energy Performance indices have been selected as main metrics for evaluating the capture plant performance. Selection of the controlled and manipulated variables was based on a process analysis and the pairing of the control loops was conducted according to the Relative Gain Array matrix. The control system disturbance rejection performance was investigated considering the influent flow rate and CO2 concentration major disturbances, either with positive and negative slope ramp signals or with periodic changes and considering different testing scenarios. Setpoint tracking of the Carbon Capture rate ability was also examined. Simulation results revealed the capability of the decentralized control system to successfully reject disturbances, demonstrating zero steady state offset, reduced overshoot and short settling time control performance. Setpoint tracking also proved to be efficient. The synergic contribution of all control loops succeeded to achieve flexible control against the action of both ramp, constant or periodic disturbances. The proposed decentralized control system showed promising perspectives for the industrial implementation.

Modeling temperature dependent and absolute carbamate stability constants of amines for CO2 capture

Thermodynamic properties and carbamate stability constants (Kc) for a dataset of 25 amines and alkanolamines, with desirable post combustion CO2 capture (PCC) solvent properties, have been studied extensively employing various gaseous phase calculations and solvation models. A comprehensive study of gaseous phase free energy and enthalpy is carried out using density functional methods [B3LYP/6-311++G(d,p)], and composite methods (G3MP2B3, G3MP2, G4MP2 and CBS-QB3). Implicit solvation models (PCM, SM8T and DivCon) and the Explicit Solvation Shell Model (ESS) were used to study solvation free energy of various neutral and ionic species present in the amine-carbamate formation reaction. Temperature dependent carbamate stability constants are calculated for the carbamate formation reaction of amines and alkanolamines to better understand the effect of temperature on temperature swing absorption-desorption PCC processes. The temperature dependency of Kc was compared against available experimental data.

Synthesis of functionalized 3D microporous carbon foams for selective CO2 capture

Porous carbon materials have been considered as the promising media for post combustion CO2 capture. Development and design of cost-effective carbons with high adsorption capacity and selectivity of CO2 over other gases at low CO2 partial pressures has attracted increasing attention. In this study, a category of functionalized 3D microporous carbon foam was prepared by using inexpensive and commercially available polyisocyanurate foam (PIR) as the precursor via a facile one-step chemical activation process. The porous structure and surface chemistry of the carbon foams can be tailored by adjusting the activation temperature and KOH/PIR mass ratio. At 25 ℃ and a CO2 partial pressure of 0.15 bar, the carbon foam of FC7001 with highest volume of fine micropores (<0.44 nm) and desirable surface chemistry exhibited exceptionally high CO2 uptake of 2.3 mmol/g whereas FC6001, which had a pure single pore size centered at 0.37 nm, showed highest Henry’s law CO2/N2 selectivity of 200. Furthermore, high CO2 uptake capacity of 19 mmol/g at CO2 pressure of 20 bar and ambient temperature was obtained for the carbon foam prepared at a higher activation temperature and KOH/precursor ratio and with a high surface area of 2207 m2/g and micropore volume of 0.876 cm3/g. Advanced characterization confirmed that the unique ultra-microporous structure and surface chemistry originated from intercalated potassium in the form of surface extra-framework ions governed the selective CO2 adsorption of the carbon foams at low CO2 partial pressures whilst the high micropore volume determined the CO2 adsorption at high CO2 pressure. This work provides a potentially new pathway to recycle polyisocyanurate foams by producing efficient CO2 adsorbents.

Partitioning and removal behaviors of PCDD/Fs, PCBs and PCNs in a modern municipal solid waste incineration system

An extensive evaluation on a modern full-scale municipal solid waste incineration system was conducted for characterizing the distribution of highly toxic chlorinated aromatics, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs), and their corresponding mass fluxes in post combustion zone. It was found that the flue gas/fly ash partitioning behaviors of chlorinated aromatics could be essentially described by their octanol-air partition coefficients (KOA) and strongly affected by the flue gas temperature. Above 93% of chlorinated aromatics formed in boiler section was partitioned into the flue gas and transported into the subsequent flue gas cleaning system, in which above 92% of Cl3–8DDs, Cl3–7DFs, Cl5–10Bs and Cl4–8Ns in flue gas was removed by the discharge of fly ash. The results of mass flux calculation indicated that the memory effect in flue gas cleaning system remarkably elevated the emission levels of chlorinated aromatics, especially the less chlorinated ones. The memory effect should mainly result from the direct chlorination mechanism mediated by the deposited particles. In addition, activated carbon injection could cause an obvious increase in PCBs emission. The obtained results provided some important implications for further reducing the emission of highly toxic chlorinated aromatics.

Environmental Assessment of a Coal Power Plant with Carbon Dioxide Capture System Based on the Activated Carbon Adsorption Process: A Case Study of the Czech Republic

The Czech Republic is introducing new technological concepts for mitigation of greenhouse gases (GHG) in coal-based energy industries. One such technology, in power plants, is post combustion CO2 capture from flue gases by activated carbon adsorption. A life cycle assessment (LCA) was used as the assessment tool to determine the environmental impacts of the chosen technology. This article focuses on a comparative LCA case study on the technology of temperature-swing adsorption of CO2 from power plant flue gases, designed for the conditions of the Czech Republic. The LCA study compares the following two alternatives: (1) a reference power unit and (2) a reference power unit with CO2 adsorption. The most significant changes are observed in the categories of climate change potential, terrestrial acidification, and particulate matter formation. The adsorption process shows rather low environmental impacts, however, the extended LCA approach shows an increase in energy demands for the process and fossil depletion as a result of coal-based national energy mix. The feasibility of the study is completed by the preliminary economical calculation of the payback period for a commercial carbon capture unit.

Thermo-kinetics, mass and heat balance in an energy optimizing furnace for primary steel making

ABSTRACT Energy optimizing furnace (EOF) is a primary steel making reactor, where the autogenous exothermic reaction heat, associated with the solute oxidation is utilized for making the steel. The thermo-kinetic reactions of the steel making process have been evaluated in the world’s largest, 65 ton EOF, at JSW Steel Ltd., Salem. The solute oxidation as a function of blow time and Si content was evaluated. The mass balance analysis showed that oxygen from the furnace atmosphere has to be entrained by the oxygen jet from the inclined supersonic lance, to completely oxidize the solutes in the melt. The heat balance showed that the power of 352 kWh per metric ton of hot metal is generated by the solute oxidation along with the post combustion. The characteristics of the inclined single hole-supersonic oxygen jet on the molten bath are brought out. Other operational aspects of the process are elaborated.

Progress in the CO2 Capture Technologies for Fluid Catalytic Cracking (FCC) Units—A Review

© Copyright © 2020 Gulec, Meredith and Snape. Heavy industries including cement, iron and steel, oil refining, and petrochemicals are collectively responsible for about 22% of global CO2 emissions. Among these industries, oil refineries account for 4–6%, of which typically 25–35% arise from the regenerators in Fluid Catalytic Cracking (FCC) units. This article reviews the progress in applying CO2 capture technologies to FCC units. Post combustion and oxyfuel combustion have been investigated to mitigate CO2 emissions in FCC and, more recently, Chemical Looping Combustion (CLC) has received attention. Post combustion capture can readily be deployed to the flue gas in FCC units and oxyfuel combustion, which requires air separation has been investigated in a pilot-scale unit by Petrobras (Brazil). However, in comparison, CLC offers considerably lower energy penalties. The applicability of CLC for FCC has also been experimentally investigated at a lab-scale. As a result, the studies demonstrated highly promising CO2 capture capacities for FCC with the application of post combustion (85–90%), oxyfuel combustion (90–100%) and CLC (90–96%). Therefore, the method having lowest energy penalty and CO2 avoided cost is highly important for the next generation of FCC units to optimize CO2 capture. The energy penalty was calculated as 3.1–4.2 GJ/t CO2 with an avoiding cost of 75–110 €/t CO2 for the application of post combustion capture to FCC. However, the application of oxyfuel combustion provided lower energy penalty of 1.8–2.5 GJ/t CO2, and lower CO2 avoided cost of 55–85 €/t CO2. More recently, lab-scale experiments demonstrated that the application of CLC to FCC demonstrate significant progress with an indicative much lower energy penalty of ca. 0.2 GJ/t CO2.

Low Pressure CO2 Capture with Amide-Based Imprinted Polymers

Bulk polymerization was used to fabricate molecularly imprinted polymer (MIP) adsorbents inherent with amine-functionality for post combustion CO2 capture. Polymerization was performed at 333 K for 24 hours using methacrylamide and ethylene glycol dimethacrylate (EGDMA) as the functional monomer and cross linker respectively, oxalic acid as the template azobisisobutyronitrile (AIBN) as the initiator and 4:1 (v/v) mixture of acetonitrile and dimethylformamide (DMF) as the porogenic solvent. The monolithic polymers were crushed and ground, followed by screening to 75-215 μm and the template was then removed from the polymeric particles by extraction using methanol and hydrochloric acid (90/10 v/v). A fixed bed adsorption column was used to investigate the performance of the dynamic CO2 uptake capacities. The X-ray Photoelectron Spectroscopy (XPS) and Fourier Transform Infrared spectroscopy (FT-IR) spectra showed a huge number of -NH2 functionality distributed on the surface of the adsorbents, which thus enhanced the CO2 adsorption uptake. The maximum CO2 capture capacity was found in the MIP with the maximum template concentration (0.40 mmol/g, SBET 258 m2/g at 0.15 bar partial pressure and temperature of 313 K). The MIPs were stable thermally up to 518 K and the isotherms displayed type II revealing a non-uniform distribution of the pore size.

Modelling and simulation of a biomass-based integrated gasification combined cycle with carbon capture: comparison between monoethanolamine and potassium carbonate

There are global efforts to reduce the impacts from climate change by limiting increases in temperature to 1.5 °C until 2030, and achieve carbon neutrality by 2050. Thus, it is necessary to design new neutral processes and systems that can meet the varying and growing demands of the population in terms of energy, water and food. One of the main carbon emitters and contributors to climate change is the energy industry, which primarily uses oil and natural gas as an energy source. Fortunately, alternative resources are available such as renewable energies that assemble various environmental and economic benefits. However, more work is necessitated to efficiently utilise these resources by designing, analysing, and optimising existing and new renewable energy-based processes. Therefore, this study proposes a net negative carbon emissions energy system that utilises waste biomass as a feedstock. A biomass based integrated gasification combined cycle combined with a post combustion carbon capture unit by means of chemical absorption is designed and analysed. Two different chemical solvents are used for comparison: Monoethanolamine (MEA) and potassium carbonate. The proposed integrated system is modelled and simulated in Aspen Plus software, and is analysed thermodynamically in terms of energy and exergy efficiencies. A sensitivity analysis is also conducted to assess the effect of varying operating conditions such as flowrate, and temperature of the lean solvent, and the pressure inside the stripper. At design conditions with 80% carbon capture, the system generates 419 kW of electricity and operates at -0.32 kg/kWh of CO2 for both the potassium carbonate and MEA systems.

U.S. DOE/NETL large pilot-scale testing of advanced carbon capture technologies

The mission of the United States (U.S.) Department of Energy/National Energy Technology Laboratory (DOE/NETL) Carbon Capture Program is to develop the next generation of advanced CO2 capture concepts for the power-generation sector. The Carbon Capture Program employs a down-selection process that graduates technologies from a large portfolio of laboratory/bench-scale projects to a smaller set of small-scale pilot projects and eventually to an even smaller group of large-scale pilot projects. At every scale, computer simulation plays a significant role in guiding experimental efforts and accelerating the overall pace of technology development. This down-selection process serves to de-risk industrial investment, given that there is insufficient information generated at the laboratory/bench scale to confidently predict eventual commercial success.The Carbon Capture Program is currently engaged in efforts to advance the next generation of capture technologies to large pilot scale. Three capture technologies have been awarded Phase I projects in a competition to build large-scale pilots for advanced energy and post combustion capture systems. In addition, six capture technologies are working toward large-scale pilot testing at Technology Center Mongstad in Norway. Advances along three innovation pathways—materials, processes, and equipment—have been critical in preparing these technologies for large pilot-scale testing.This paper describes the approach that is being followed by the Carbon Capture Program to advance the technologies and provides brief descriptions of the technical innovations that have prepared individual technologies for large pilot-scale testing.

Sodium carbonate-based post combustion carbon capture utilising trona as main sorbent feed stock

In the pursuit of shifting technology towards sustainable, environmentally benign processes, post-combustion carbon capture technology is recognised to be a timely mitigation option. This paper presents the development of a novel sodium carbonate-based post combustion carbon capture process utilising the carbonate mineral trona (trisodium hydrogendicarbonate dihydrate) as main sorbent feedstock source. The energy penalty, the fraction of energy sacrificed to capture CO2 relative to the net energy produced serves as main performance indicator. Investigations on the correlative relationship between energy penalty as a function of capture efficiency are carried out by retrofitting the process to a 600 MW reference coal-fired power plant. The energy penalty of the global system features a distinct local minimum of 3.99%, corresponding to a CO2 capture efficiency of 90.00% and a CO2 outlet purity of 99.90%. The Specific Primary Energy Consumption for CO2 Avoided (SPECCA) index corresponding to this minimum is evaluated to be SPECCA = 0.514MJkgCO2-1. Sensitivity analyses on the effect of increasingly high SO2 flue gas volume fractions ySO2 show that the capture efficiency is virtually unimpaired for calcination temperatures of 190 ⩽T⩽280 °C and ySO2 ranging from 0.50 to 0.70%. Whilst commercially available CO2 capture technology is energy intense and prone to sorbent degradation, the process developed retains high capture efficiencies of calcium oxide-based looping cycles at low operating temperatures and eliminates the predisposition of amine-based sorbents utilised in scrubbing capture schemes to deplete due to the presence of SO2 in the inlet flue gas stream. It can be concluded that sodium carbonate based post-combustion capture processes are a competitive alternative to existing CO2 capture technologies.

Feasibility Study of Emission Reduction on Marine Engine with Variation of Emulsified Water Concentration and Turbocharger Compression Ratio

The characteristics of black carbon and nitrogen oxide reduction versus the water content of emulsion fuel were studied by numerical methods, and a method of reducing fuel consumption was achieved by adjusting the turbocharger compression ratio. The results of the combustion period characteristics, versus the three types of emulsion fuel and the turbocharger compression ratios, shows that the combustion period is shortened in the order of CR00 &gt; CR01 &gt; CR02 &gt; CR03, according to the compression ratio of the turbocharger. As the fuel water content increases, the combustion period is shortened in the order of EMDO16 &lt; EMDO13 &lt; EMDO10. The nitrogen oxide and black carbon reduction was because the combustion period increased, with increasing compression ratio, while the combustion period was shortened, with increasing moisture content of emulsion fuel. This also caused is an increase in the combustion pressure and a shortening of the combustion period, due to the expansion of the volume, in turn due to the micro-explosion of water. This may be due to the shortening of the post combustion period and the reduction of black carbon emissions. In addition, combustion was accelerated in the order—CR00 &gt; CR01&gt; CR02&gt; CR03. By optimizing the water content of the emulsion fuel and turbocharger compression ratio, while considering the exhaust emission and combustion state, reduction of the fuel consumption rate and output improvement are shown.