When selecting GTL to monetise natural gas, hydrocarbons are converted into a range of products whose characteristics include a higher performance than their crude oil derived counterparts.
Clean and valuable GTL products
The products are virtually pure paraffinic hydrocarbons that have excellent combustion properties. GTL fuel contributes to the reduction of local emissions. The commodity transport markets, into which the main products will be sold, are very large compared to the potential global GTL production.
A study on “Cost-effectiveness of alternative transportation fuels for reducing Europe’s petroleum dependence” concluded that GTL fuel is the most cost effective way to meet EU targets for the transport industry. The study was taking into account differences in Greenhouse gas (GHG) emissions between the options of passenger cars, light duty commercial vehicles and heavy duty trucks. Other fuels considered included bio ethanol, BTL fuel, CNG, hydrogen and LPG.
Environmental regulations are the main driving force behind increasing demand for higher quality base oils. GTL base oil has excellent product properties and is an important value adding supplement to the GTL value chain
Properties of the different GTL products
The main product is synthetic diesel, but other possible products are naphtha, lubricant base oils, jet fuel and waxes, as well as some LPG. All products are clean with zero sulphur content and excellent emission properties.
- GTL diesel is a clean and more environmental friendly product than oil refined products. It reduces local emissions of particulates, nitrogen oxide, carbon monoxide and hydrocarbons. GTL diesel has a cetane number of 75-80 versus refinery diesel of around 50. The cetane number indicates how quickly the fuel will auto-ignite, and how evenly it will combust. A higher cetane number represents a lower flame temperature, providing a reduction in the NOx formation.
- The paraffinic nature and the purity of GTL naphtha results in higher ethylene and propylene yields compared to oil based conventional naphtha feedstock. This makes it an ideal steam cracker feedstock for ethylene and propylene manufactures.
- Expansion of the global LPG industry (both capacity and market) has been faster than most other energy markets and is expected to further accelerate during the years to come. Due to its high content of propylene and butylenes it might be possible to sell GTL LPG with better margin if the GTL plant is located close to a steam refinery and /or an olefin plant.
- GTL base oils have excellent properties with low volatility, no sulphur and a high viscosity index that are required in high performance engine designs. Environmental regulations are the main driving force behind increasing demand for higher quality base oils.
CO2 / HSE/”Environmental footprint”
The ultra clean GTL diesel offers a significant reduction on local pollution compared to conventional diesel due to the lack of presence of particles, low emissions of NOx, Sulphur and CO.
However, due to the inherent nature of the GTL conversion process and the need for firing in the synthesis gas production process, CO2 will be released unless captured. Thus, for GTL plants without CO2 capture/storage, the emissions from a Well-to-Wheel perspective are about 10% higher than from a conventionally produced diesel.
CO2 capture potential favours combined GTL and EOR possibilities, and can represent an opportunity to set a green footprint as a supplier of clean fuels. Favourable process conditions enables relatively cost efficient capture of about 40-60% of the total emissions brining the emissions below diesel from oil refineries , while the remaining release is subject to conventional flue gas CO2 capture.