– The Pearl GTL is the largest implementation of FT synthesis, located in Qatar and
owned by Shell (Fleisch et al. 2002).
– CHOREN’s has realized a 1MWth Carbo-V gasifier coupled to a Fischer-Tropsch
reactor in 2002 (Dimitriou et al. 2018).
If cobalt-based catalyst is used, the FT synthesis takes place at 230
C and 25 bar
(Fleisch et al. 2002). The product distribution can be estimated using the AndersonSchulz-Flory (ASF) model with an alpha value of 0.85 which favors the production
of middle distillates (Swanson et al. 2010; Fürnsinn 2007; Taschler 2009). A product
distribution of 60% diesel, 25% gasoline, and 25% kerosene can be achieved after
the hydrocracking unit, as reported for the Shell Middle Distillate Synthesis (SMDS)
process (Eilers et al. 1990).
1.5.5.2 Methanol-to-Gasoline (MTG) Synthesis
In the methanol-to-gasoline (MTG) process, the first step is represented by methanol
synthesis from syngas at 50 bar and 250
C (LeBlanc et al. 1994; Lee 1990). The
produced methanol is vaporized, before it enters a dehydration reactor, where a
mixture of DME, methanol, and water is produced at 404
C. The effluent from the
DME reactor is combined with the recycled gas from the product separator and
enters the MTG reactor, where it is converted at 415
C and 21.2 bar to mainly
hydrocarbons and water over zeolite catalysts (ZSM-5) (Maiden 1988). The gasoline
fraction in the product stream is usually about 36 wt% of the methanol and DME
input (Yurchak 1988). The hot reactor effluent is cooled by heat exchange with the
gas recycled from the vapor-liquid separator. It is then further cooled to about 200
C
before it passes to the vapor-liquid separator, where gas, liquid gasoline, and water
are the outputs.
The MTG process was developed by Mobil scientists in the 1970s (Keil 1999). A
Mobil MTG plant was operated in Motunui, New Zealand, from 1985 to 1997 and
produced 14,500 bbl/d of gasoline. The plant was designed to meet one-third of
New Zealand’s demand for transport fuels (Maiden 1988). The fuel was composed
mainly of isoparaffins and aromatics with low benzene content and essentially zero
sulfur (Spath and Dayton 2003).
The first coal-to-gasoline MTG plant, utilizing the second-generation MTG
technology, was constructed by Jincheng Anthracite Mining Group (JAMG) in
China (Dimitriou et al. 2018). The plant started up in 2009 and its current capacity
is 2500 bpd (Dimitriou et al. 2018).
1.5.5.3 Topsoe Integrated Gasoline Synthesis (TIGAS)
The main principle of the TIGAS process is the incorporation of the methanol
synthesis and the DME synthesis into a single process. It was developed by Haldor
Topsoe to reduce investment costs and subsequently production costs of gasoline
(Topp-Jorgensen 1988). The process has been demonstrated in Houston, Texas,
using natural gas as feed to the process. The plant capacity was 1 t per day gasoline.
The plant started working in early 1984 and terminated in January 1987 after
22
P. Bartocci et al.
owned by Shell (Fleisch et al. 2002).
– CHOREN’s has realized a 1MWth Carbo-V gasifier coupled to a Fischer-Tropsch
reactor in 2002 (Dimitriou et al. 2018).
If cobalt-based catalyst is used, the FT synthesis takes place at 230
C and 25 bar
(Fleisch et al. 2002). The product distribution can be estimated using the AndersonSchulz-Flory (ASF) model with an alpha value of 0.85 which favors the production
of middle distillates (Swanson et al. 2010; Fürnsinn 2007; Taschler 2009). A product
distribution of 60% diesel, 25% gasoline, and 25% kerosene can be achieved after
the hydrocracking unit, as reported for the Shell Middle Distillate Synthesis (SMDS)
process (Eilers et al. 1990).
1.5.5.2 Methanol-to-Gasoline (MTG) Synthesis
In the methanol-to-gasoline (MTG) process, the first step is represented by methanol
synthesis from syngas at 50 bar and 250
C (LeBlanc et al. 1994; Lee 1990). The
produced methanol is vaporized, before it enters a dehydration reactor, where a
mixture of DME, methanol, and water is produced at 404
C. The effluent from the
DME reactor is combined with the recycled gas from the product separator and
enters the MTG reactor, where it is converted at 415
C and 21.2 bar to mainly
hydrocarbons and water over zeolite catalysts (ZSM-5) (Maiden 1988). The gasoline
fraction in the product stream is usually about 36 wt% of the methanol and DME
input (Yurchak 1988). The hot reactor effluent is cooled by heat exchange with the
gas recycled from the vapor-liquid separator. It is then further cooled to about 200
C
before it passes to the vapor-liquid separator, where gas, liquid gasoline, and water
are the outputs.
The MTG process was developed by Mobil scientists in the 1970s (Keil 1999). A
Mobil MTG plant was operated in Motunui, New Zealand, from 1985 to 1997 and
produced 14,500 bbl/d of gasoline. The plant was designed to meet one-third of
New Zealand’s demand for transport fuels (Maiden 1988). The fuel was composed
mainly of isoparaffins and aromatics with low benzene content and essentially zero
sulfur (Spath and Dayton 2003).
The first coal-to-gasoline MTG plant, utilizing the second-generation MTG
technology, was constructed by Jincheng Anthracite Mining Group (JAMG) in
China (Dimitriou et al. 2018). The plant started up in 2009 and its current capacity
is 2500 bpd (Dimitriou et al. 2018).
1.5.5.3 Topsoe Integrated Gasoline Synthesis (TIGAS)
The main principle of the TIGAS process is the incorporation of the methanol
synthesis and the DME synthesis into a single process. It was developed by Haldor
Topsoe to reduce investment costs and subsequently production costs of gasoline
(Topp-Jorgensen 1988). The process has been demonstrated in Houston, Texas,
using natural gas as feed to the process. The plant capacity was 1 t per day gasoline.
The plant started working in early 1984 and terminated in January 1987 after
22
P. Bartocci et al.