Tropsch Diesel Research Articles

Production of Transportation Fuels from Fischer–Tropsch Waxes: Distillation, Blending, and Hydrocracking

Nowadays, transportation fuels such as diesel or gasoline are standardly produced from crude oil refining. These petroleum-based products are gradually replaced by more environmentally friendly sources, such as Fischer–Tropsch diesel fractions and other biofuels. The present work reports the distillation of Fischer–Tropsch (FTS) waxes and its use for fuel production by (i) blending the FTS wax diesel fraction with fossil diesel (7:93; 15:85; 30:70; and 50:50 wt.%) and (ii) blending the FTS wax heavy fraction (360–700 °C) with vacuum gas oil (10–50 wt.%) followed by hydrocracking at industrial operating conditions (T = 420 °C, WHSV = 0.5–1.0 h−1, P = 10.0 MPa). The obtained products in both cases were analysed and compared with standard EN590 for petroleum-diesel fuels. Overall, our results point to the suitability of the distillation of FTS waxes for renewable fuel production, either by straight blending of the diesel petroleum-based products or co-hydrocracking of the heavy fraction with vacuum gas oil.

Comparative Life Cycle Assessment of Alternative Marine Fuels

With the stricter rules introduced by the policymakers in maritime transportation, harmful emissions are aimed to be mitigated. Consequently, studies on alternative fuels have emerged, and different methods had adopted to evaluate fuel choices. Within this context, a well-to-wake life cycle assessment method is used to determine the environmental impacts of the fuel options. Included fuels in the study are ammonia, biodiesel, Dimethyl ether, electro Fischer Tropsch diesel fuel, electro methanol, Fischer Tropsch diesel fuel, hydrogen, liquefied natural gas, liquefied petroleum gas, marine diesel oil, marine gas oil, marine bio-oil, methanol, pyrolysis oil, renewable diesel, straight vegetable oil, and ultra-low sulfur heavy fuel oil. The paper aims to evaluate the fuels according to the 2050 strategy of the International Maritime Organization. Hence, black carbon, carbon monoxide, carbon dioxide, nitrous oxide, nitrogen oxide, sulfur oxide, particulate matter, methane, and volatile organic compounds are considered emissions. During the study, an ocean tanker model available in the GREET Model 2022 was used for life cycle inventory analysis, and life cycle assessment was conducted by Environmental Footprint Method 3.0, which is included in the OpenLCA. The assessment was carried out according to climate change, acidification, freshwater ecotoxicity, marine eutrophication, terrestrial eutrophication, non-cancer human toxicity, particulate matter, and photochemical ozone formation criteria. The results show that out of eight criteria, marine bio-oil became the most dominant choice due to the consumption of CO2 and methane while producing and low emission generation during combustion.

Performance and emissions of a diesel engine fueled by coal-based diesel fuels and their blends with polyoxymethylene dimethyl ethers

The objective of this study was to investigate the performance and emissions of a diesel engine fueled by coal-based diesel fuels and their blends with oxygenated fuel polyoxymethylene dimethyl ethers (PODEn). First, coal-based Fischer–Tropsch (FT) diesel fuel was blended with hydrogenated diesel fuel at three volume ratios of 40%/60%, 50%/50%, and 60%/40%, denoted as T6W4, T5W5, and T4W6, respectively. Then, PODEn were added into the T4W6 fuel with the volume ratios of 10%, 20%, and 30% to evaluate its effects on the performance and emissions of a coal-based diesel engine. The results showed that the output torques and powers of the three coal-based diesel blends were slightly lower than those of the petroleum diesel fuel. The brake specific fuel consumption (BSFC) of the coal-based diesel fuels was almost the same as that of the petroleum diesel fuel. The brake thermal efficiencies (BTE) of the coal-based diesel blends were slightly lower than that of the petroleum diesel fuel, and the maximum reduction was 1.59%. The pollutant emissions of T5W5 were the closest to those of petroleum diesel fuel. The nitrogen oxides (NOx) emissions of T4W6 were lower, with a maximum decrease of 11.18% compared with the petroleum diesel. The carbon monoxide (CO) and hydrocarbon (HC) emissions of T6W4 were the highest, with maximum increases of 36.79% and 29.05%, respectively. The smoke emissions of T4W6 and T6W4 were higher than those of petroleum diesel fuel. Adding PODEn into T4W6 lowered the engine power and torque but increased the BSFC and BTE. The output torque and power of the diesel engine were further reduced when PODEn were blended with T4W6, with the maximum reductions of 17.76% and 16.96%, respectively. With an increase in the PODEn blending ratio, BSFC and BTE increased gradually, and the maximum increase in the BTE was 1.57%. Blending PODEn with the fuel effectively improved the emission characteristics of the coal-based diesel fuels. The NOx emissions increased slightly, but the emissions of HC, CO, and smoke were reduced significantly, with maximum reductions of 24.42%, 31.67%, and 82.35%, respectively.

Maritime fuels of the future: what is the impact of alternative fuels on the optimal economic speed of large container vessels

This study aims to determine the most appropriate alternative fuel technology to comply with possible different imposed emission regulations while ensuring optimal business performance. In this context, the most suitable alternative fuel technology minimizes the required freight rate while maximizing overall performance on technological, environmental, and other criteria. A decision support tool was developed combining the overall performance of alternative fuels based on technological, environmental, and other criteria via a simple multiattribute rating technique model with a financial model based on discounted cash flow analysis. In this model, also an optimization model is implemented to minimize the required freight rate by optimizing for economic vessel speed. This model provides quantified insights into the financial and operational effects of transitioning via either a 'market-based measure' regulatory scenario or an 'emission cap' scenario if current fuels do not reach the zero-emission targets in the future. Based on the analysis, it can be concluded that upgraded bio-oil, Fischer–Tropsch diesel and liquefied bio-methane can be considered the 'most promising' alternative maritime fuels of the future. Current fuels such as Heavy fuel oil and Liquified natural gas remain the 'most probable' to retain dominance without regulations. If there is a transition toward these alternative fuels, this will also lead to a shift toward lower sailing speeds.

An Overview of Promising Alternative Fuels for Road, Rail, Air, and Inland Waterway Transport in Germany

To solve the challenge of decarbonizing the transport sector, a broad variety of alternative fuels based on different concepts, including Power-to-Gas and Power-to-Liquid, and propulsion systems, have been developed. The current research landscape is investigating either a selection of fuel options or a selection of criteria, a comprehensive overview is missing so far. This study aims to close this gap by providing a holistic analysis of existing fuel and drivetrain options, spanning production to utilization. For this purpose, a case study for Germany is performed considering different vehicle classes in road, rail, inland waterway, and air transport. The evaluated criteria on the production side include technical maturity, costs, as well as environmental impacts, whereas, on the utilization side, possible blending with existing fossil fuels and the satisfaction of the required mission ranges are evaluated. Overall, the fuels and propulsion systems, Methanol-to-Gasoline, Fischer–Tropsch diesel and kerosene, hydrogen, battery-electric propulsion, HVO, DME, and natural gas are identified as promising future options. All of these promising fuels could reach near-zero greenhouse gas emissions bounded to some mandatory preconditions. However, the current research landscape is characterized by high insecurity with regard to fuel costs, depending on the predicted range and length of value chains.

Combustion and Emission Characteristics of Dual Fuel Engine for Different Parameters

The effects of compression ratio and fuel delivery advance angle on the combustion and emission characteristics of premixed methanol charge induced ignition by Fischer Tropsch diesel engine were investigated using a CY25TQ diesel engine. In the process of reducing the compression ratio from 16.9 to 15.4, the starting point of combustion is fluctuating, the peak of in-cylinder pressure and the maximum pressure increase rate decrease by 44.5% and 37.7% respectively. The peak instantaneous heat release rate increases by 54.4%. HC and CO emissions are on a rising trend. NOx and soot emissions were greatly decreased. The soot emission has the biggest drop of 50%. Reducing the fuel delivery advance angle will make the peak of in-cylinder pressure and the peak of pressure rise rate increase while the peak of heat release rate decreases. The soot emission is negatively correlated with the fuel delivery advance angle. When the fuel delivery advance angle is 16° CA, the soot emissions increased the most by 130%.

Measuring sustainability of renewable diesel production using a multi‐criteria decision matrix

AbstractThis study presents a multi‐criteria decision matrix approach to the sustainability analysis of renewable diesel processes. The criteria include environmental, economic, technical, and fuel‐quality aspects. The main objective is to establish a comprehensive approach to the sustainability analysis of alternative manufacturing processes. A combination of an analytical hierarchy process method and an entropy method is used to obtain both subjective and objective weighting factors to achieve a more reliable and comprehensive comparison among alternatives. The technique for order of preference by similarity to ideal solution (TOPSIS) method is used to rank the alternatives based on the distance of each alternative to the ideal and non‐ideal solutions. This analysis indicates that the most sustainable processes are the process associated with Fischer–Tropsch diesel, and the catalytic hydrotreatment of vegetable oils to produce green diesel (GD I). The results determined that algae‐based green diesel (GD III) was the least favorable process. This is because GD III has the highest impact on the water scarcity footprint and unit production cost indicators. This multi‐criteria analysis with estimated weight factors can be an effective generic method for sustainability assessment of alternative manufacturing processes. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

Advanced Biofuels Based on Fischer-Tropsch Synthesis for Applications in Diesel Engines.

This paper focuses on the evaluation of the fuel properties of Fischer–Tropsch diesel blends with conventional diesel. Incorporating this advanced fuel into conventional diesel production will enable the use of waste materials and non-food materials as resources, while contributing to a reduction in dependence on crude oil. To evaluate the suitability of using Fischer–Tropsch diesel, cetane number, cetane index, CFPP, density, flash point, heat of combustion, lubricity, viscosity, distillation curve, and fuel composition ratios using multidimensional GC × GC-TOFMS for different blends were measured. It was found that the fuel properties of the blended fuel are comparable to conventional diesel and even outperform conventional fuel in some parameters. All measurements were performed according to current standards, thus ensuring the repeatability of measurements for other research groups or the private sector.

The Investigation into the Tribological Impact of Alternative Fuels on Engines Based on Acoustic Emission

The wide use of different alternative fuels (AL) has led to challenges to the internal combustion (IC) engine tribology. To avoid any unpredicted damages to lubrication joints by using AL fuels, this study aims to accurately evaluate the influences of alternative fuels on the tribological behavior of IC engines. Recent achievements of the acoustic emission (AE) mechanism in sliding friction provide an opportunity to explain the tribological AE responses on engines. The asperity–asperity–collision (AAC) and fluid–asperity–shearing (FAS) mechanisms were applied to explain the AE responses from the piston ring and cylinder liner system. A new adaptive threshold–wavelet packets transform (WPT) method was developed to extract tribological AE features. Experimental tests were conducted by fueling three fuels: pure diesel (PD), biodiesel (BD), and Fischer–Tropsch (F–T) diesel. The FAS–AE indicators of biodiesel and F–T diesel show a tiny difference compared to the baseline diesel using two types of lubricants. Biodiesel produces more AAC impacts with higher AAC–AE responses than F–T diesel, which occurs at high speeds due to high temperatures and more particles after combustion than diesel. This new algorithm demonstrated the high performance of using AE signals in monitoring the tribological impacts of alternative fuels on engines.

A Comparative Study of Biofuels and Fischer–Tropsch Diesel Blends on the Engine Combustion Performance for Reducing Exhaust Gaseous and Particulate Emissions

The worldwide consumption of fossil hydrocarbons in the road transport sector in 2020 corresponded to roughly half of the overall consumption. However, biofuels have been discreetly contributing to mitigate gaseous emissions and participating in sustainable development, and thus leading to the extending of the commercial utilization of internal combustion engines. In this scenario, the present work aims at exploring the effects of alternative fuels containing a blend of 15% ethanol and 35% biodiesel with a 50% fossil diesel (E15D50B35) or 50% Fischer–Tropsch (F-T) diesel (E15FTD50B35) on the engine combustion, exhaust emissions (CO, HC, and NOx), particulate emissions characteristics as well as the performance of an aftertreatment system of a common rail diesel engine. It was found that one of the blends (E15FTD50B35) showed more than 30% reduction in PM concentration number, more than 25% reduction in mean particle size, and more than 85% reduction in total PM mass with respect to conventional diesel fuel. Additionally, it was found that the E15FTD50B35 blend reduces gaseous emissions of total hydrocarbons (THC) by more than 25% and NO by 3.8%. The oxidation catalyst was effective in carbonaceous emissions reduction, despite the catalyst light-off being slightly delayed in comparison to diesel fuel blends.

Synthesis of European Union Biorefinery Supply Networks Considering Sustainability Objectives

Increasing the use of renewable energy sources is one of the most important goals of energy policies in several countries to build a sustainable energy future. This contribution proposes the synthesis of a biorefinery supply network for a case study of the European Union (EU-27) under several scenarios based on a mathematical programming approach. Several biomass and waste sources, such as grains, waste oils, and lignocellulosics, are proposed to be utilized, and various biofuels including first, second, and third generations are produced such as bioethanol, green gasoline, biodiesel, Fischer Tropsch (FT) diesel, and hydrogen. The aim of this study is to evaluate the capabilities of EU-27 countries to be able to meet the Renewable Energy Directive (RED II) target regarding the share of renewable energy in the transport sector by 2030 in each Member State while not compromising the current production of food. A generic mathematical model has been developed for the multi-period optimization of a biorefinery supply network with the objective of maximizing sustainability profit. The solutions obtained show that biomass and waste are promising raw materials to reach and go beyond the EU’s renewable energy target in the transport sector for the year 2030. However, some countries would need to provide additional subsidies for their companies to achieve at least a non-negative economic performance of biofuel production.

Influence of the addition of titanium oxide nanoparticles to Fischer-Tropsch diesel synthesised from coal on the combustion characteristics and particulate emission of a diesel engine

The use of Fischer–Tropsch (F–T) diesel synthesised from coal in automobiles can alleviate petroleum shortages and promote clean utilisation of coal. Because F–T diesel does not contain oxygen, in this study, we added TiO2 nanoparticles and n-octanol to the F–T diesel to serve as oxygenated enhancers to increase the oxygen content and reduce the particulate matter emission of F–T diesel. To achieve better combustion characteristics and emission performance, TiO2 nanoparticles with different concentrations (20, 50, and 100 ppm) were dispersed to the fuel blends of F–T diesel and n-octanol to determine the optimum amount of TiO2 nanoparticles. The brake thermal efficiency (BTE), combustion stability, number concentration, and size distribution of the ultrafine particulate (UFP) emission of the three nano-emulsion fuels were investigated on a turbocharged heavy-duty diesel engine. The experimental results indicated that the BTE of the F–T diesel and that of the nano-emulsion fuel T50 increased by 0.75 % and 2.26 %, respectively, compared with petro-diesel. The nano-emulsion fuels had higher peak cylinder pressure and peak heat release rate owing to the faster combustion rate caused by the micro-explosion of fuel droplets and higher thermal conductivity caused by the high surface-to-volume ratio of TiO2 nanoparticles. Moreover, the nano-emulsion fuels exhibited higher cyclic variations of peak cylinder pressures and more dispersed corresponding crank angles with the increase in the concentration of TiO2 nanoparticles. Compared with petro-diesel, the soot emission of the F–T diesel was reduced by an average of 27.32 % at various loads, whereas that of the optimal T50 decreased by an average of 43.61 %. Additionally, the number concentration of UFPs of T50 was reduced by an average of 21.2 % compared to the F–T diesel. At low loads, the three nano-emulsion fuels exhibited greater geometric mean diameters (GMDs) of UFPs and lower ratios of nucleation mode particulates (NMPs) owing to the higher fuel viscosity in the pre-injection stage at a lower in-cylinder temperature. At medium and high loads, the nano-emulsion fuels exhibited smaller GMDs of UFPs and higher ratios of NMPs owing to micro-explosion and secondary atomisation at higher temperatures.

Petroleum and Fischer–Tropsch diesel soot: A comparison of morphology, nanostructure and oxidation reactivity

This study investigated the physical properties of the exhaust soot particles from a light-duty diesel engine fueled with an ultra-low sulfur diesel fuel (ULSD) and Fischer–Tropsch diesel fuel synthesized from coal (CFT). The morphology and nanostructure of the obtained soot were characterized using a high-resolution transmission electron microscopy, while the oxidation reactivity of soot was evaluated by the thermogravimetric analysis (TGA). Despite the different fuel properties, both the ULSD and CFT soot exhibits similar changes in fractal dimension, primary particle size and nanostructure parameters (including fringe length, separation distance and tortuosity) when varying the engine speed or load. However, the CFT soot has smaller fractal dimensions and primary particle sizes and a more ordered nanostructure as compared to the ULSD soot. The TGA results demonstrate that the CFT soot has the higher apparent activation energy, indicating that it is less reactive than the ULSD soot. The length and tortuosity of the fringes within the soot structure are found to have definite correlations with soot reactivity.

Study on physicochemical properties of biodiesel and Fischer–Tropsch diesel exhaust particle

ABSTRACT In this study, the physicochemical properties of exhaust particulate matter (PM) from the combustion of biodiesel, Fischer–Tropsch (F-T) diesel, and diesel are studied. The experiment was carried out on the four-stroke air-cooled single-cylinder diesel engine under the same engine operating conditions. The microstructure, particle size, box-counting dimension, element, and oxidation characteristics of the particles were studied. The results show that, compared with diesel particles, the average particle size of biodiesel particles is reduced by 10.8%, and the average particle size of F-T diesel particles is reduced by 27%. Biodiesel particles are closely arranged, followed by diesel particles, and F-T diesel particles are loose. Compared with diesel particles, the relative content of O element in biodiesel particles is high, and the relative content of O element in F-T diesel particles is low. The content of soluble organic fraction (SOF) in biodiesel, diesel, and F-T diesel particles was 23.4%, 17.6%, and 12.7%, respectively. In addition, compared with diesel particles, the activation energy of biodiesel particles is the lowest, while the activation energy of F-T diesel particles is the highest, it means that oxidation of biodiesel particles is more actively.

Study on emission and particulate matter characteristics from diesel engine fueled with n-pentanol/Fischer–Tropsch diesel

ABSTRACT N-pentanol has become one of the hotspots of mixed fuel research due to its renewability and good combustion and emission performance. Some valuable advances have been made in the study of burning Fischer–Tropsch diesel in engines. However, research on n-pentanol/Fischer-Tropsch diesel fuel blends has rarely been reported. Therefore, in the current work, an experimental study was carried out on a single-cylinder engine and diesel, Fischer–Tropsch diesel and n-pentanol/Fischer–Tropsch diesel were investigated at different load ratios (10%, 25%, 50%, 75%, 100%), the difference in emission characteristics and particle properties at n-pentanol ratio (5%, 10%, 20%), rotation speed (2700 r/min, 3600 r/min) was analyzed. The results show that CO, HC, NOX and soot of Fischer–Tropsch diesel are lower than that of diesel and CO and HC increased while NOX, and soot reduced with the addition of n-pentanol. The arrangement between Fischer–Tropsch diesel particles is tighter than that of diesel. This phenomenon is more pronounced with the addition of n-pentanol. Fischer–Tropsch diesel has the highest degree of graphitization and decreases with the addition of n-pentanol. The C-OH, C = O, and sp3/sp2 of Fischer–Tropsch diesel are relatively low, with the addition of n-pentanol, C-OH, C = O, and sp3/sp2 of the particle surface increased. The soot particles of the blended fuel are more orderly than diesel.

Comprehensive environmental impact assessment of a combined petroleum coke and natural gas to Fischer-Tropsch diesel process

In this study, a well-to-wheels life cycle assessment was conducted to determine the environmental impacts from disposing of petroleum coke by converting it into liquid fuel. Specifically, this work is an extension of the life cycle assessment of the petcoke standalone gasification to diesel study which also includes two new pathways for converting petroleum coke and natural gas to Fischer Tropsch diesel operated with and without carbon capture and sequestration (CCS). Impact categories were calculated using the EPA’s TRACI 2.1 US-Canada 2008 midpoint method in SimaPro software. In addition, the impact of grid emissions on the overall process was assessed using two representative Canadian locations with high (Alberta) and low (Ontario) grid emissions. The results of each impact category were compared among the designs and against conventional petroleum and oil sands derived diesel. Key findings showed that the proposed designs when operated with CCS in the low-emissions-grid location had life cycle GHG emissions between 281–291 gCO2-eq/km compared to the conventional petroleum and oil sands derived diesel with GHG emissions of 305 and 348 gCO2-eq/km respectively. Nevertheless, the various tradeoffs between processes indicated that there was no clearly superior design among the candidates. However, the design which uses a natural gas reformer that is integrated directly into the radiant syngas cooler of a petcoke gasification unit has the lowest cost of CO2 avoided ($144/tCO2-eq), and so is likely the best choice for reducing environmental impacts.

Development of a skeletal oxidation mechanism for Fischer–Tropsch diesel surrogate based on decoupling method and particle swarm optimization

As an alternative liquid fuel, Fischer–Tropsch (FT) diesel has received significant attentions due to its characteristics of high efficiency and low emission. In this study, a surrogate fuel containing iso-hexadecane and n-dodecane with a mole ratio of 0.16:0.84 is formulated for real FT diesel by mimicking its combustion-related physicochemical properties. Mechanisms of these two components are developed based on decoupling methodology: skeletal sub-mechanisms describing iso-hexadecane and n-dodecane cracking process are constructed and combined with a reduced C0–C4 core mechanism, and then the Arrhenius parameters of certain reactions are tuned by particle swarm optimization algorithm to improve prediction accuracy. The optimized mechanisms are validated against experimental results of ignition delays, species concentrations and laminar flame speeds for iso-hexadecane and n-dodecane, respectively. Finally, by merging all the sub-mechanisms mentioned above, a skeletal oxidation model for FT diesel surrogate including 73 species and 324 reactions is obtained and employed in 3D CFD simulations to validate the ignition behavior of FT diesel sprays in a constant-volume combustion vessel; the simulation results show good agreement with experimental data.

Potential of e-Fischer Tropsch diesel and oxymethyl-ether (OMEx) as fuels for the dual-mode dual-fuel concept

The dual-mode dual-fuel combustion strategy allows operating over the entire engine map by implementing a diffusive dual-fuel combustion at high engine loads. This requires increasing the amount of exhaust gas recirculation to control the NOx emissions, which penalizes the soot levels. At these conditions, the use of non-sooting fuels as the e-Fischer Tropsch Diesel (e-FT) and oxymethylene dimethyl ethers (OMEx) could be a potential way to avoid the NOx-soot trade-off. The experimental results acquired in a compression ignition multi-cylinder medium-duty engine evidence that the higher oxygen content of OMEx allows reducing the soot emissions at high loads to near zero levels, while e-FT promotes a soot reduction of around 20% as compared to diesel. Nonetheless, the low lower heating value of OMEx leads to excessive injection durations, enlarging the combustion process and increasing the fuel consumption around 1.3–7.2% and 1.4–5.3% as compared to diesel and e-FT, respectively, depending on the engine load. Finally, the well to wheel analysis confirms the potential in reducing the carbon dioxide footprint of OMEx (14.8–69%) and e-FT (0.3–38.5%) compared to diesel, as they can be synthetized via direct air capture as a source of carbon and using renewable energy.

Gas emissions and particulate matter of non-road diesel engine fueled with F-T diesel with EGR

ABSTRACTThe gas emissions and particulate matter of non-road diesel engine fueled with Fischer–Tropsch diesel fuel were investigated. The test was carried out on a four-stroke, water-cooled, single-cylinder engine under different the exhaust gas recirculation (EGR) rates such as 0%, 15%, and 30% at 2,700 rpm, 25%, 50%, and 75% load. The test results showed that when the EGR rate is less than 15%, nitrogen oxides (NOx) are reduced significantly, while hydrocarbon (HC) and carbon monoxide (CO) are increased less than 5%. However, when the EGR rate was 30%, HC and CO were maximally increased to 13.2% and 13.3%, respectively. Additionally, the Field Emission Scanning Electronic Microscope test and Energy Dispersive Spectrometer test were conducted. With increase of EGR rates, the micromorphology of particles was mainly showed as chain-like status and the growth of number concentration of particle was mainly contributed by the nuclear particle when the engine was at 25% load. In contrast, the micromorphology of particles was principally showed as clustered-like status, and the aggregated particles were dominating growth at 50% and 75% load. Moreover, as EGR rates increased, the degree of agglomeration and carbon content were gradually decreased at 25% load. The test also showed the opposite tendency at 50% and 75% load.

Production of Synthetic Fischer–Tropsch Diesel from Renewables: Thermoeconomic and Environmental Analysis

In this study, a novel integrated system for production of advanced synthetic diesel is proposed and analyzed from thermodynamic, economic, and environmental perspectives. This system consists of solid oxide electrolyser (SOEC), entrained gasification (EG), Fischer-Tropsch (FT), and upgrading processes. Eleven different combinations of precursor syngas production through steam and CO2 co-electrolysis and biomass gasification are investigated. Results show that increasing share of produced syngas in electrolyser unit results in higher system efficiencies, emission savings, and levelized cost of FT diesel. Moreover, different options of heat and mass flow recovery are considered. It is concluded that recovery of produced medium pressure steam in the system is highly beneficial and recommended. Besides, it is shown that while oxygen recovery is the best choice of mass recovery, hydrogen recovery for internal use has adverse effect on the system performance. Although CO2 and water recovery do not show any pro...