Gas-to-liquid Diesel Research Articles

Experimental study of Gas-To-Liquid (GTL) and diesel fuel blends evaporation behaviour and droplet lifetime through Leidenfrost effect

Gas to Liquid (GTL) fuel is considered a clean alternative fuel and has been given much attention to replacing conventional fuel. Evaporation behaviour and droplet lifetime are critical aspects that need to be determined as these aspects can affect the fuel spray properties and improve the combustion process. In this study, a set of GTL–diesel fuel blends are prepared, which are G20, G50, G80, and G100 (the number represents the GTL percentage fuel ratio in the fuel blends). Subsequently, using a single droplet drop test on the hot plate (Leidenfrost effect), the GTL fuel blends droplet lifetime and evaporation behaviour are visualised using a high-speed camera connected to long-distance microscopy. An image processing system and a MatLab were used to measure and analyse the droplet evaporation data. Comparing the fuel characterisation of the GTL fuel and conventional diesel fuel, the GTL fuel shows a lower value in all properties tested except for the calorific value, cetane number, and vapour pressure. The qualitative results through the Leidenfrost effect have shown that increasing the GTL fuel ratio (20% to 100%) decreases the heating phase duration (37.3 % to 14.4 %) and evaporation rate (1.29 mm 2/s to 1.10 mm 2/s) while increasing their steady evaporation phase duration and droplet lifetime. The shorter period to achieve steady evaporation is beneficial as the spray inside the chamber has a limited time to evaporate for combustion.

Effects of Chemical Compositions and Cetane Number of Fischer–Tropsch Fuels on Diesel Engine Performance

Fischer–Tropsch synthetic (FT) fuels are expected to be an ideal alternative for diesel fuel to achieve higher thermal efficiency and reduction in exhaust emissions because of their characteristics of being aromatic-free, sulfur-free, and high cetane number. In this study, the effects of chemical compositions and cetane number of FT fuels on diesel engine performance were investigated by using a commercial GTL (Gas-to-Liquids) diesel fuel synthesized by the FT method and blended paraffinic hydrocarbon fuels made to simulate FT fuels with different chemical compositions and cetane numbers. At first, a commercial diesel fuel (JIS No.2) and GTL were examined by varying the intake oxygen concentrations with cooled EGR. Compared with diesel fuel, GTL shows shorter premixed combustion, smaller heat release peak, and longer diffusion combustion duration at both high and medium conditions due to the higher cetane number. Further, by using the GTL, a limited improvement in thermal efficiency and exhaust emission reduction of NOx have been obtained, but no significant reduction in the smoke emissions is achieved, even though FT fuels have been considered smokeless due to their aromatic-free characteristics. Next, three types of paraffinic hydrocarbon fuels with cetane numbers of 78, 57, and 38 were blended as simulated FT fuels and were examined under the same experimental apparatus and operation conditions. For the low cetane number simulated FT fuel (cetane number 38 fuel), the results show that the ignition delay and premixing period are significantly longer at low intake oxygen concentration conditions, meaning that the premixing of low cetane number fuel is more sufficient than other fuels, especially under the high EGR rate conditions, resulting in fewer smoke emissions. Furthermore, with CN38 fuel, an excellent indicated thermal efficiency was obtained at the high load condition. To summarize the results, the low cetane number FT fuel shows a potential to achieve higher thermal efficiency and reduction in exhaust emissions on commercial diesel engines with EGR.

Evaluation of the Economic Potentials of a Mini Gas-to-Liquids (GTL) Plant in Nigeria

In this paper, the economic potential of using a mini gas-to-liquids (GTL) plant for monetization of stranded associated gas in Nigeria was extensively evaluated. Feedstock to the plant comprises 50 MMscfd of treated stranded associated gas from Assa North in the Niger Delta region of Nigeria. 5000 b/d of GTL diesel product was realized after simulation using Fischer-Tropsch (FT) type modular gas-to-liquids technology. Economic analyses were performed for a wide range of economic conditions to determine the economic potentials of the GTL project. From the result, it was realized that for base case, the net present value (NPV) of the project was US$32,421 barrel-liquid-per-day (BLPD) corresponding to US$162.1 million for 5000 b/d of GTL diesel produced. The payout time (POT) was 4.48 years while the net cash ratio (NCR) was US$81.83 million. The internal rate of return (IRR) was 22.2%. From the sensitivity analyses performed, it was realized that the variable having the most influence on the NPV was the GTL product price (the price of diesel) followed by the capital cost of the GTL plant and then the natural gas price. It was also realized that the operating cost of the plant has the least (negligible) effect on the NPV of the project. Furthermore, it was realized that GTL project remained profitable for diesel prices above US$80/bbl as long as the price of natural gas was maintained below US$2.2/Mscf at 15% discount rates. In general, it was realized that the mini-GTL project was profitable for diesel prices equal to or greater than US$80/bbl as long as discount rates remained below 20% for base CAPEX and OPEX. It was recommended that the government of Nigeria subsidizes the price of natural gas to increase the profitability of mini-GTL projects creating a greater participation by the private investors and thereby reducing the volume of associated gas flared.

Experimental study of micro-explosion and puffing of gas-to-liquid (GTL) fuel blends by suspended droplet method

In this study, a set of GTL–diesel fuel blends (G20, G50, G80, and G100, where the number represents the percentage of GTL fuel in the fuel blend) are prepared. Subsequently, using the suspended droplet method in a controlled heating chamber, the evaporation behaviour of these GTL fuel blends is visualised using a high-speed camera connected to a long-distance microscope. It is found that, among the tested fuel blends, puffing is not observable for G100, whereas micro-explosions are absent for G20. In comparison, the remaining fuel blends experience both these phenomena. In addition, the highest enlargement factor is observed for G20, followed by G50 and G80, whereas G50 has the highest micro-explosion intensity, followed by G80 and G100. Finally, the numbers and sizes of the child droplets are determined by adjusting the detection threshold, and it is found that G50 has the highest number of child droplets, followed by G80, G100, and G20. The results indicate that the presence of 50% GTL fuel in a GTL–diesel fuel blend (by volume) can lead to the best droplet micro explosions compared to the rest of the tested fuel blends.

Environmentally friendly synthesis route of terpolymers derived from alkyl acrylates and their performance as additives for liquid hydrocarbon products

In this work acrylic terpolymers with different alkyl radicals were synthesized to find out the alkyl radicals with the lowest average carbon number in poly (alkyl acrylate) (PAA) samples to reach the highest viscosity index with lower concentration of the polymer. Firstly, esters of acrylic monomers are synthesized with a heteroazeotrope forming solvent not miscible with methanol, alleviating the separation process. It was followed the syntheses of terpolymers to be evaluated the solubility of them in petroleum products. After being conducted the solubility tests of these polymers in several lube oil base stocks, the suitable PAA with different molecular weights were chosen and sent them for ultrasonic testing to check their shear stability indices or the stability to mechanical destruction. Found the polymer with boundary solubility in lube oil base stocks in order to attain the highest viscosity index and mechanical destruction stability. Found low temperature, electrical conductivity and wear resistance properties of GTL (Gas to Liquid) diesel dosed with these additives. Laboratory equipment’s illustrations as well as an environmentally friendly synthesis route of the copolymers were given.

Velocity Field Measurements with High Speed Structural Image Velocimetry in the Primary Atomization Region of Future Diesel Fuels

<div class="section abstract"><div class="htmlview paragraph">Fuel spray breakup in combustion engines and hence all following processes are determined by the primary atomization. Due to high optical densities as well as high velocities and structures in the μm-range, the measurement of sprays in the near nozzle region is extremely challenging. Therefore, the processes of the primary breakup are not fully understood yet, although these processes are very important for simulation of spray atomization. One important property of a spray is the velocity distribution close to the nozzle outlet. With the newly developed Structural Image Velocimetry (SIV) technique it is possible to visualize spray structures in the near nozzle region and track them via cross-correlation algorithms, so that two-dimensional velocity fields of the spray can be derived. The initial SIV technique is improved with a new high-speed setup, allowing to observe also the temporal behavior of the spray velocities during the injection. Within this work, velocities of potential future diesel fuels were measured under engine relevant conditions with a variation of fuel pressure, fuel temperature and gas pressure based on the ECN Spray A conditions. Velocity fields of Oxymethlyenether 3-5 (OME) as an E-Fuel and Hydrogenated Vegetable Oil (HVO) as a Bio-Fuel were measured and compared with Gas-to-Liquid Diesel (GTL) as a reference fuel. For constant fuel pressures, the velocity distribution for OME shows significantly different values than for GTL and HVO, having about 15 % lower values and much lower deceleration behavior in downstream direction. Obviously the OME spray has a weaker air-fuel interaction. This can be attributed to a lower density leading to reduced nozzle outlet velocities and a lower Weber number.</div></div>

Analyzing the effects of Gas-to-Liquid (GTL) diesel blending on the efficiency and emissions of petroleum refineries and transport fuels in the U.S. and Europe

The transport sector is fast changing with demand for distillates increasing amidst declining gasoline consumption in many markets especially in the developed world. Increasingly refineries are stretched to operate less efficiently and this is manifested through a drop in efficiency as a consequence of increasing diesel production via less efficient routes, particularly on the marginal barrel of diesel. It has been suggested that this decline in diesel production efficiency, as the ratio of gasoline to diesel (G/D) production drops, can partly be mitigated through the use of Gas-to-Liquid (GTL) diesel. In this paper we adopted refinery Linear-Programming models to represent the refining system in Europe as well as a district in the U.S. to investigate the effects of increased availability of GTL diesel to a refiner on the energy efficiency and GHG emissions of refineries. Here we showed that indeed there is an improvement in diesel production efficiency with increasing GTL concentrations, but this efficiency gain (<0.5%) is insufficient to counteract the higher energy consumption and emissions associated with the production of GTL, thus leading to an overall decline in life cycle efficiency (up to 5%), and an increase in life cycle GHG emissions (up to 2%).

Designing a Surrogate Fuel for Gas-to-Liquid Derived Diesel

Synthetic diesel fuel produced from natural gas via gas-to-liquid (GTL) technology is referred to as ultraclean fuel but is still challenged for full certification as diesel fuel. GTL diesel lacks certain hydrocarbons and chemical constituents, which although are benign to the environment, result in a trade-off in performance when used in a diesel engine. To boost GTL diesel physicochemical properties and thereby enable its use in conventional diesel engines, GTL diesel needs improvement. This can be achieved by mixing suitable additives to the GTL diesel and through the development of surrogate fuels that have fewer components. Screening of thousands of additives is a tedious task and can be done efficiently via computer based modeling to quickly and reliably identify a small number of promising candidates. These models are used to guide the formulation of five surrogates and predict their physicochemical properties. These surrogates are further verified using rigorous mathematical tools as well as throu...

Integration of non-fuel coproducts into the GREET model.

The life-cycle greenhouse gas (GHG) emissions of alternative fuels that are capable of replacing conventional, petroleum-derived gasoline and diesel continue to be scrutinized for policy implementation. These alternative fuel technologies can also produce a number of value-adding nonfuel coproducts that require thorough and rigorous assessment in order to achieve an accurate life-cycle GHG emissions value. By using the gas to liquids (GTL) diesel pathway as a proxy for other alternative fuel pathways with coproducts, this paper examines how integration of coproduct analysis using the substitution method is possible within the existing framework and functionality of the GREET model. Using this approach, a GREET-compatible external tool was developed to calculate the life-cycle inventory of GTL coproducts to determine the life-cycle GHG emissions of GTL diesel using the substitution method. In addition to having built-in regional scenarios, this tool allows the user the flexibility to configure a given GTL product slate and to calculate the life-cycle GHG emissions of GTL diesel based on a given product composition. Using this protocol, the life-cycle GHG emissions of GTL diesel can range from 71.7 to 95.7 gCO2e/MJ on a well to wheel basis, with the range in carbon intensity being dependent on the mix of coproducts. These results highlight a weakly understood relationship between fuel and chemical products in LCA models. The coproduct integration approach described herein could potentially be incorporated into fuel LCA models, such as GREET, to allow users to further understand the potential environmental benefits of alternative fuel pathways, such as GTL.

A Comparison of the Stability Performance of Blends of Paraffinic Diesel and Petroleum-Derived Diesel, with RME Biodiesel Using Laboratory Stability Measurement Techniques

In 2012, a new specification for synthetic fuels containing up to 7% biodiesel (FAME) was approved (CEN TS 15940). This specification allows the sale of neat paraffinic diesel, such as Gas-to-Liquids (GTL) diesel, to captive fleets in Europe. Several aspects are important in the final end-use application, including the stability of the fuel. The current study evaluated the stability of neat GTL diesel and FAME/paraffinic fuel blends via standard laboratory stability tests commonly used to study petroleum-derived fuels. The stability of GTL diesel, containing biodiesel, was evaluated using the Rancimat, PetroOxy, and ASTMD2274 tests. Selected samples were also evaluated using ASTM D5304. The Rancimat results indicated that FAME/GTL diesel blends performed similar to the FAME/petroleum derived fuel blends. In the PetroOxy test, the addition of more than 2 v/v% of a highly stable FAME resulted in an unexpected boost in the stability of the FAME/GTL diesel blend. The ASTM D2274 results were generally insensitive to the addition of FAME. The correlation between the PetroOxy and Rancimant tests was evaluated and found to be base fuel dependent. From this study it was concluded that GTL diesel (in blends with FAME) performed similar to petroleum-derived reference fuels in standard laboratory stability.

Comparative evaluation of the blends of gas-to-liquid (GTL) fuels and biodiesels with diesel at high idling conditions: an in-depth analysis on engine performance and environment pollutants

The effect of high-idling conditions at different engine performance-emission parameters were investigated using blends of GTL–diesel and biodiesel–diesel.

Formaldehyde LIF detection with background subtraction around single igniting GTL diesel droplets

Formaldehyde is an important combustion intermediate, which is often used for the analysis of turbulent flames, internal combustion engines or droplet/spray ignition processes. Due to its high concentration in hydrocarbon fuel combustion, laser induced fluorescence (LIF) of formaldehyde can easily be excited (e.g. 339, 343, 353 and 355nm) and measured (360–550nm). However, it is often superimposed by background emission from other combustion intermediates as, e.g. polycyclic aromatic hydrocarbons (PAHs).We present formaldehyde LIF excitation spectra obtained with a XeF excimer laser in combination with a spectrometer and an ICCD camera in dependence of pressure (50mbar to 20bar). For formaldehyde LIF and background excitation, we selected the wavelengths 353.373 and 353.386nm, respectively. LIF measurements at the background wavelength contain a rising formaldehyde contribution with increasing pressure. We present a novel method for the calculation of the real background. This method is applied to the ignition of single gas-to-liquid (GTL) diesel droplets. However, the method can also be applied to other fuels. In the case of a GTL diesel ignition experiment (628K, 3bar) the real background amounted to only 30% of the emission which was measured at the background excitation wavelength (353.386nm).

Experimental Investigation and Prediction of Density and Viscosity of GTL, GTL–Biodiesel, and GTL–Diesel Blends As a Function of Temperature

The purpose of this study is to experimentally investigate the densities and viscosities of gas-to-liquid (GTL)–biodiesel and GTL–diesel blends for various fuel temperatures and blending ratios. The biodiesel used in this study was derived from soybean oil, and was added to GTL from 20% to 100% by volumetric ratio. In the case of the GTL–diesel blend, diesel was added at 30% and 70% by volumetric ratio. Based on the experimental results, the empirical correlations for densities and viscosities were derived for variations in fuel temperatures and blending ratios. The densities of GTL–biodiesel and GTL–diesel blends decreased linearly with increasing fuel temperature and GTL is insensitive to temperature change compared to biodiesel and diesel. The dynamic and kinematic viscosities of GTL–biodiesel and GTL–diesel blends decreased exponentially with increasing fuel temperatures. As the fuel temperatures increased, the rate of change in viscosities for the temperature change significantly decreased. The increase of biodiesel and diesel in GTL blended fuels caused an increase in density. At a given temperature, the rates of density increase in the GTL–biodiesel and GTL–diesel blends showed similar values. The rates of density increase caused by biodiesel blending were higher than that caused by diesel blending due to the high density of biodiesel. With increased fuel temperature, the variations in viscosity from the blending of biodiesel or diesel with GTL decreased. In terms of the interdependence of density and kinematic viscosity, the density and the kinematic viscosity were positively correlated. At the same density conditions, an increase in biodiesel or diesel content in GTL blended fuels caused a decrease in the kinematic viscosity of the blended fuels.

Evaluation of the Impacts of Biodiesel and Second Generation Biofuels on NOx Emissions for CARB Diesel Fuels

The impact of biodiesel and second generation biofuels on nitrogen oxides (NO(x)) emissions from heavy-duty engines was investigated using a California Air Resources Board (CARB) certified diesel fuel. Two heavy-duty engines, a 2006 engine with no exhaust aftertreatment, and a 2007 engine with a diesel particle filter (DPF), were tested on an engine dynamometer over four different test cycles. Emissions from soy- and animal-based biodiesels, a hydrotreated renewable diesel, and a gas to liquid (GTL) fuel were evaluated at blend levels from 5 to 100%. NO(x) emissions consistently increased with increasing biodiesel blend level, while increasing renewable diesel and GTL blends showed NO(x) emissions reductions with blend level. NO(x) increases ranged from 1.5% to 6.9% for B20, 6.4% to 18.2% for B50, and 14.1% to 47.1% for B100. The soy-biodiesel showed higher NO(x) emissions increases compared to the animal-biodiesel. NO(x) emissions neutrality with the CARB diesel was achieved by blending GTL or renewable diesel fuels with various levels of biodiesel or by using di-tert-butyl peroxide (DTBP). It appears that the impact of biodiesel on NO(x) emissions might be a more important consideration when blended with CARB diesel or similar fuels, and that some form of NO(x) mitigation might be needed for biodiesel blends with such fuels.

Greenhouse Gas Emission Evaluation of the GTL Pathway

Gas to liquids (GTL) products have the potential to replace petroleum-derived products, but the efficacy with which any sustainability goals can be achieved is dependent on the lifecycle impacts of the GTL pathway. Life cycle assessment (LCA) is an internationally established tool (with GHG emissions as a subset) to estimate these impacts. Although the International Standard Organization's ISO 14040 standard advocates the system boundary expansion method (also known as the "displacement method" or the "substitution method") for life-cycle analyses, application of this method for the GTL pathway has been limited until now because of the difficulty in quantifying potential products to be displaced by GTL coproducts. In this paper, we use LCA methodology to establish the most comprehensive GHG emissions evaluation to date of the GTL pathway. The influence of coproduct credit methods on the GTL GHG emissions results using substitution methodology is estimated to afford the Well-to-Wheels (WTW) greenhouse gas (GHG) intensity of GTL Diesel. These results are compared to results using energy-based allocation methods of reference GTL diesel and petroleum-diesel pathways. When substitution methodology is used, the resulting WTW GHG emissions of the GTL pathway are lower than petroleum diesel references. In terms of net GHGs, an interesting way to further reduce GHG emissions is to blend GTL diesel in refineries with heavy crudes that require severe hydrotreating, such as Venezuelan heavy crude oil or bitumen derived from Canadian oil sands and in jurisdictions with tight aromatic specifications for diesel, such as California. These results highlight the limitation of using the energy allocation approach for situations where coproduct GHG emissions reductions are downstream from the production phase.

Premixed ignition behavior of alternative diesel fuel-relevant compounds in a motored engine experiment

A motored engine study using premixed charges of fuel and air at a wide range of diesel-relevant equivalence ratios was performed to investigate autoignition differences among surrogates for conventional diesel fuel, gas-to-liquid (GTL) diesel fuel, and biodiesel, as well as, n-heptane. Experiments were performed by delivering a premixed charge of vaporized fuel and air and increasing the compression ratio in a stepwise manner to increase the extent of reaction while monitoring the exhaust composition via Fourier transform infrared (FTIR) spectrometry and collecting condensable exhaust gas for subsequent gas chromatography/mass spectrometry (GC/MS) analysis. Each fuel demonstrated a two-stage ignition process, with a low-temperature heat release (LTHR) event followed by the main combustion, or high-temperature heat release (HTHR). Among the three diesel-relevant fuels, the magnitude of LTHR was highest for GTL diesel, followed by methyl decanoate, and conventional diesel fuel last. FTIR analysis of the exhaust for n-heptane, the conventional diesel surrogate, and the GTL diesel surrogate revealed that LTHR produces high concentrations of aldehydes and CO while producing only negligible amounts of CO 2. Methyl decanoate differed from the other two-stage ignition fuels only in that there were significant amounts of CO 2 produced during LTHR; this was the result of decarboxylation of the ester group, not the result of oxidation. GC/MS analysis of LTHR exhaust condensate for n-heptane revealed high concentrations of 2,5-heptanedione, a di-ketone that can be closely tied to species in existing autoignition models for n-heptane. GC/MS analysis of the LTHR condensate for conventional diesel fuel and GTL diesel fuel revealed a series of high molecular weight aldehydes and ketones, which were expected, as well as a series of organic acids, which are not commonly reported as products of combustion. The GC/MS analysis of the methyl decanoate exhaust condensate revealed that the aliphatic chain acts similarly to n-paraffins during LTHR, while the ester group remains intact. Thus, although the FTIR data revealed that decarboxylation occurs at significant levels for methyl decanoate, it was concluded that this occurs after the aliphatic chain has been largely consumed by other LTHR reactions.

Performance and emission characteristics of a gas to liquid fuelled engine

The objective of the study is, through investigation of visualization and an engine test, to pursue a lower emission engine using GTL (gas to liquid) while maintaining thermal efficiency and fuel consumption. A sulphur-free (&lt;13 ppm) diesel fuel was used as the reference fuel, and the characteristics of the GTL diesel fuel were investigated. As a physical property, the GTL fuel has approximately the same cetane value as the diesel but has low values of PAHs (polycyclic aromatic hydrocarbons), boiling point, density, viscosity, and surface tension. In visualization of spray and combustion, images were taken using a high-speed video camera and analysed by their penetration and evaporation characteristics in comparison with current diesel fuel. Also, in an engine test, a heavy-duty diesel engine which has six-cylinder 11.15 litre displacements was used to test the performance. The results showed that mixture formation of the GTL fuel is faster than that of diesel fuel, depending on the physical properties. In the engine test, a considerable reduction in PM (particulate matter) emission was observed, due to the enhanced fuel atomization and air entrainment, and a reduction in NO x emission can be achieved without deteriorating b.s.f.c. (brake specific fuel consumption).

Effect of Gas-to-Liquid Diesel Fuels on Combustion Characteristics, Engine Emissions, and Exhaust Gas Fuel Reforming. Comparative Study

New diesel-type fuels such as biodiesels and gas-to-liquid (GTL) fuel have been developed in order to aid vehicle manufacturers in achieving forthcoming emission regulations, by improving engine out emissions and exhaust gas after-treatment performance. Furthermore, synthetic fuels are virtually free of sulfur and aromatic hydrocarbons and can improve the performance and durability of the catalytic fuel reformers that are designed to provide H2 to fuel cells, internal combustion (IC) engines, and after-treatments. Combustion and exhaust-gas reforming experiments with GTL and ultralow sulfur diesel (ULSD) were run under several engine and reformer operating regimes. Using a single cylinder bench engine, the combustion of GTL fuel (and blends with conventional diesel fuel) was found to reduce NOx emissions substantially and improve engine thermal efficiency but led to an increase in smoke for the default injection timing in the experiment. However, by optimizing the injection timing in a GTL-fueled engine, the harmful emissions of NOx and smoke were both reduced simultaneously while still giving improvements in engine thermal efficiency. In general, it was found that the NOx/particulates tradeoff curve shifted to lower emissions for GTL fuel and GTL fuel blends. During exhaust-gas reforming, the use of GTL fuel was found to increase fuel conversion, while producing more hydrogen and less methane.

GTL: An Attractive Route For Gas Monetization?

This article, written by Technology Editor Dennis Denney, contains highlights of paper SPE 88642, "GTL: Is It an Attractive Route for Gas Monetization?," by Osama Abdul Rahman and Mohamed Al-Maslamani, SPE, Qatar Petroleum, prepared for the 2004 SPE Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, UAE, 10-13 October. The gas-to-liquid (GTL) conversion of natural gas into synthetic fuel is an active area of development. Many companies are involved in research, pilot plants, or demonstration units with the objective of reducing capital and operating costs of this technology. Major factors affecting the economics of the GTL process are gas price and capital cost. The GTL process could be an attractive way to monetize stranded gas reserves where the application of pipeline or liquefied-natural-gas (LNG) technology is not technically or economically feasible because the gas is either too far from a market or the gas reserves cannot support an LNG plant. Introduction The GTL process involves the conversion of natural gas into a clean source of energy, mainly diesel and naphtha. As the sulfur and aromatics specifications for diesel oil become tighter and complying with exhaust/emission requirements becomes more difficult, the GTL diesel market expands. Production of refinery diesel with ultralow sulfur content from crude oil will be expensive. The production cost of GTL diesel oil, which contains near-zero sulfur and less than 1% aromatics, will become competitive.

Australia making crucial GTL decisions

This paper presents a brief summary and comparison of heavy vehicle emissions using Mossgas synthetically derived diesel as opposed to a US Regular Federal 49-state number 2 diesel fuel. A series of engine dynamometer and heavy-duty chassis dynamometer tests were performed at West Virginia University early in 1999.The Mossgas gas-to-liquid (GTL) low sulphur diesel fuel is produced primarily by the conversion of olefins to distillate (COD) process in conjunction with a high temperature Fisher–Tropsch technology process.Findings were that there were significant emission benefits when using Mossgas GTL diesel fuel. Oxides of nitrogen (NOx) and particulate matter (PM) emissions were substantially lower when compared to normal fossil fuel-derived diesel. Additionally the benefits have been found to cut across different engine technologies, various test cycles, engine age (1991–1999), as with or without engine aftertreatment catalysts.The Mossgas GTL diesel meets the world-wide challenge to produce environmentally friendly transportation fuels and sets the benchmark for future diesel specifications. Accordingly Mossgas has petitioned the US Department of Energy to register this fuel as an alternative fuel under its EPACT program [1], [2].