part of the reactor, the biomass wastes are then mixed with hot stream water and the
salt transported downward by gravitational action. The excess salt produced from the
process is then removed by the brine removal system. A typical overall reaction for
glucose taking place in the process can be written as:
2C 6 H 12 O 6 þ 7H 2 O ! 9CO 2 þ 2CH 4 þ CO þ 15H 2 :
The end gases depend on the working temperature of the system. Based on the
reaction pathway, three main pathways for the production of gases are highlighted
which are:
• For substitute natural gas production, CO has to be minimised.
• For hydrogen production, H 2 has to be maximised.
• Synthesis gas production requires CH 4 to be minimised.
4.3.3 Separation System
At the supercritical working conditions, the gases are soluble in the working
supercritical water and will leave the reactor and passes to the heat exchanger and
cooler. After cooling, the gases are separated from the water phase which is equipped
with CO 2 scrubber. The gasses separated are then stored in the storage containers for
further treatments.
Figure 13 depicts the composition of the product gases. As shown in the figure, a
significant percentage of important gases can be generated using this technology.
However, it is worth noting that the composition of the product gases depends on the
choice end gases as identified earlier.
4.4 Syngas Treatment Chain
After treatment, different products are obtained among which includes chemicals,
diesel, coal, petcoke, natural gas and naphtha, methanol, dimethyl ether (DME, also
known as wood ether), ammonia, Fischer-Tropsch liquid (renewable transportation
fuels like Fischer-Tropsch diesel), etc. The treatment chain of the synthesis gas is
shown in Fig. 14.
The different products from the process can be classified according to their uses
as follows:
• Hydrogen – Hydrogen can be used in electricity generation in the form of fuel
cells, as well as transportation fuel. Hydrogen technology is already well developed across the global transportation sector.
• Steam – The steam generated in the process can also be used to drive turbines for
electricity generation.
Supercritical Water Gasification (SCWG) Technology for Municipal Solid Waste. . .
195
salt transported downward by gravitational action. The excess salt produced from the
process is then removed by the brine removal system. A typical overall reaction for
glucose taking place in the process can be written as:
2C 6 H 12 O 6 þ 7H 2 O ! 9CO 2 þ 2CH 4 þ CO þ 15H 2 :
The end gases depend on the working temperature of the system. Based on the
reaction pathway, three main pathways for the production of gases are highlighted
which are:
• For substitute natural gas production, CO has to be minimised.
• For hydrogen production, H 2 has to be maximised.
• Synthesis gas production requires CH 4 to be minimised.
4.3.3 Separation System
At the supercritical working conditions, the gases are soluble in the working
supercritical water and will leave the reactor and passes to the heat exchanger and
cooler. After cooling, the gases are separated from the water phase which is equipped
with CO 2 scrubber. The gasses separated are then stored in the storage containers for
further treatments.
Figure 13 depicts the composition of the product gases. As shown in the figure, a
significant percentage of important gases can be generated using this technology.
However, it is worth noting that the composition of the product gases depends on the
choice end gases as identified earlier.
4.4 Syngas Treatment Chain
After treatment, different products are obtained among which includes chemicals,
diesel, coal, petcoke, natural gas and naphtha, methanol, dimethyl ether (DME, also
known as wood ether), ammonia, Fischer-Tropsch liquid (renewable transportation
fuels like Fischer-Tropsch diesel), etc. The treatment chain of the synthesis gas is
shown in Fig. 14.
The different products from the process can be classified according to their uses
as follows:
• Hydrogen – Hydrogen can be used in electricity generation in the form of fuel
cells, as well as transportation fuel. Hydrogen technology is already well developed across the global transportation sector.
• Steam – The steam generated in the process can also be used to drive turbines for
electricity generation.
Supercritical Water Gasification (SCWG) Technology for Municipal Solid Waste. . .
195