一体化麻风树航煤制备系统模拟

Integrated Systems for Jet Biofuel Production from Jatropha curcas: A Process Simulation Study

Introduction

Civil aviation is responsible for nearly 5 % of total radiative forcing of climate and 2.5 % of annual global CO₂ emissions, while the demand on Jet fuel is rising rapidly. As such, Jet Biofuel (JBF) has been recognised by the aviation industry as the best option to mitigate its carbon footprint. In this regard, Jatropha curcas has proved to be a promising biomass for JBF production due to its unique competencies over other energy crops. Not only can its oil be converted into high performance fuels, but also its fruit residues are considered a valuable source for multiple energy carriers. However, jatropha is not yet fully utilised in the Jet Biofuel industry. Therefore, this study presents three novel integrated systems that utilise all parts of the jatropha fruit to produce JBF.

These systems integrate the conventional hydroprocess along with one of three thermochemical processes including gasification, pyrolysis and hydrothermal liquefaction. Aspen Plus™ is used to develop the systems and investigate the optimum amongst them based on Jet Biofuel yield. All the three systems resulted in significant increments in the JBF yield. While, the hydroprocess-gasification system demonstrated promising results; whereby, 65 wt.% of the jatropha whole-fruit is converted into green liquid fuels with 57 % Jet Biofuel selectivity. The results indicate over a 90 % increment in JBF yield as compared to the utilisation of jatropha oil alone in the best reported scenarios.

Keywords: jatropha, Jet Biofuel, Hydroprocess, Fischer-Tropsch, Gasification, Pyrolysis, Hydrothermal liquefaction.

Civil aviation contributes to nearly 2.5 % of global carbon emissions, which is predicted to double in the coming three decades (ICAO, 2016). Meanwhile, Jet Biofuel (JBF) produced from renewable resources has been intensively investigated and proved to be a promising technology to mitigate the carbon footprint of aviation sector. As airplanes depend exclusively on liquid fuels as compared to road transportation, the shifting of the refining process towards maximising JBF becomes a favourable practice (Anand et al., …). Currently, four main JBF production pathways have been certified, including Oil to Jet (OTJ) by the conventional hydroprocess, Gas to Jet (GTJ) by gasification of biomass followed by Fischer-Tropsch technology, Alcohol to Jet (ATJ) by bio-alcohol upgrading…
…and Hydroprocessed Esters and Fatty Acids (HEFA) pathway, which is the most mature and widely adopted method for producing JBF from vegetable oils or animal fats. Despite the progress in JBF technologies, feedstock availability and cost remain major barriers to large-scale deployment. Hence, non-edible oil crops such as Jatropha curcas have gained attention due to their ability to grow on marginal lands without competing with food crops.

Jatropha curcas , commonly known as jatropha, produces seeds containing 30–40 wt.% oil, which can be processed via hydrodeoxygenation, decarboxylation, and isomerisation to yield drop-in jet fuel components. However, after oil extraction, approximately 60 % of the fruit mass remains as residual biomass—comprising seed cake, husks, and shells—which is often underutilised or discarded. This residue, rich in lignocellulosic content, presents a substantial opportunity for energy recovery through thermochemical conversion routes.

In this study, three integrated biorefinery systems were designed and simulated using Aspen Plus™ to maximise JBF output by utilising the entire jatropha fruit. Each system combines the conventional hydroprocessing unit (for converting extracted oil into jet-range hydrocarbons) with one of the following thermochemical processes applied to the leftover solid residue:

1. Hydroprocess-Gasification System : The residue is gasified to produce syngas (mainly CO and H₂), which is then cleaned and conditioned before being fed into a Fischer-Tropsch synthesis unit to generate synthetic crude. This synthetic crude is further upgraded to jet fuel.
2. Hydroprocess-Pyrolysis System : The residue undergoes fast pyrolysis to produce bio-oil, which is subsequently hydrotreated to remove oxygen and improve stability, yielding additional renewable liquid fuels, including jet fuel blendstocks.
3. Hydroprocess-Hydrothermal Liquefaction (HTL) System : The wet residue is processed via HTL in subcritical water to produce biocrude, which is then upgraded via hydrotreating to obtain hydrocarbon fuels compatible with aviation standards.

Process integration focuses on heat and power recovery, hydrogen recycling, and synergistic use of intermediates between units to enhance overall efficiency. Mass and energy balances were established for each configuration, and performance was evaluated based on net JBF yield (kg per kg of dry jatropha whole fruit), carbon efficiency, and selectivity toward jet fuel range hydrocarbons (C₈–C₁₆).

Simulation results show that all three integrated systems significantly outperform standalone oil-based JBF production. The hydroprocess-gasification system achieves the highest performance, converting 65 wt.% of the raw jatropha fruit into green liquid fuels, with 57 % selectivity to jet fuel , resulting in a total JBF yield improvement of over 90 % compared to conventional HEFA-only processes that use only the oil fraction.

The pyrolysis-integrated system yields moderate improvements, limited by lower bio-oil quality and higher char formation, while the HTL system shows potential for processing wet feedstocks without drying, reducing energy input but requiring further optimisation for scale-up.

This work demonstrates that full valorisation of jatropha fruit through integrated biorefining can dramatically increase jet fuel output and improve process sustainability. Among the configurations, the hydroprocess coupled with gasification emerges as the most efficient pathway for maximising JBF production from jatropha biomass.

These findings highlight the importance of holistic feedstock utilisation in advancing sustainable aviation fuel technologies and support the development of next-generation biorefineries capable of delivering high-yield, low-carbon jet fuels. Future work should focus on techno-economic analysis and life cycle assessment of these integrated systems to evaluate commercial viability and environmental impact.