hemicellulose. The cellulose and hemicellulose are carbohydrates types, while lignin
contains aromatic derivatives, which when hydrolysed, products such as phenol and
other carbohydrates derivatives are produced. The feeds system of the reactor
contains enhanced setups, designed and developed to handle the common organics
found in MSW. As part of the handling methods, the biomass size is reduced to a
suitable size for the plant using the inbuilt cutting mill. The most common available
reactors are designed to operate at a capacity of 100 kg/h, with a maximum of 20%
dry biomass, at 350 bar and 700
C operating pressure and temperature, respectively.
This means, it is enhanced to handle a high percentage of wet biomass, which are the
most challenging components of MSW. The feed system of the reactor is dosed into
the reaction chamber by a mass flow controlled, high-pressure metering pump
serving as a heat exchanger.
4.3.2 Reaction System
As shown in the diagram, the VERENA pilot reactor depicted in Fig. 12 is a down
flow reactor. The vessel in the lower part of the reactor takes the mixture from down
through the head of the reactor and to the heat exchanger. The VERENA pilot
reactor is generally a different supercritical reactor in the sense that heterogamous
catalysts are not required for the production of gases. The system utilises the brine
produced from biomass as a catalyst for the system. This makes it a promising MSW
biomass treatment technology, as it can handle even biomass containing chlorine,
sulphur, etc. which are the major challenges of other technologies [42].
The process of heating the biomass moderately to critical temperature helps in
preventing the precipitation of inorganic salts in the heat exchanger. However, since
the heating of the biomass to the working temperature takes place in the downstream
Fig. 12 The basic flow of supercritical gasification process (Adapted with permission from: [42])
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contains aromatic derivatives, which when hydrolysed, products such as phenol and
other carbohydrates derivatives are produced. The feeds system of the reactor
contains enhanced setups, designed and developed to handle the common organics
found in MSW. As part of the handling methods, the biomass size is reduced to a
suitable size for the plant using the inbuilt cutting mill. The most common available
reactors are designed to operate at a capacity of 100 kg/h, with a maximum of 20%
dry biomass, at 350 bar and 700
C operating pressure and temperature, respectively.
This means, it is enhanced to handle a high percentage of wet biomass, which are the
most challenging components of MSW. The feed system of the reactor is dosed into
the reaction chamber by a mass flow controlled, high-pressure metering pump
serving as a heat exchanger.
4.3.2 Reaction System
As shown in the diagram, the VERENA pilot reactor depicted in Fig. 12 is a down
flow reactor. The vessel in the lower part of the reactor takes the mixture from down
through the head of the reactor and to the heat exchanger. The VERENA pilot
reactor is generally a different supercritical reactor in the sense that heterogamous
catalysts are not required for the production of gases. The system utilises the brine
produced from biomass as a catalyst for the system. This makes it a promising MSW
biomass treatment technology, as it can handle even biomass containing chlorine,
sulphur, etc. which are the major challenges of other technologies [42].
The process of heating the biomass moderately to critical temperature helps in
preventing the precipitation of inorganic salts in the heat exchanger. However, since
the heating of the biomass to the working temperature takes place in the downstream
Fig. 12 The basic flow of supercritical gasification process (Adapted with permission from: [42])
194
A. A. Gado et al.