**2. Hybrid filtration combustion for solid fuels**

IPM is a thermochemical process proven to be a feasible option to address current global requirements for cleaner energy sources and processes [22]. This technology is known to be able to produce H2 from several feedstocks and allows the direct use of liquid and gaseous fuels that interact with an inert solid matrix.

**53**

*Syngas Fuel Production from Carbonaceous Feedstocks Using Hybrid Porous Media*

The common approaches to use the technology are the stationary and transient

A relation between IPM combustion and solid fuel gasification converges into hybrid filtration combustion (HFC), a process that combines the properties of the aforesaid processes by replacing a fraction of the inert solid's volume with a solid fuel. In this case, a reaction wave is produced by a flow that can contain hot air, H2O(g), or a gaseous fuel-air mixture that propagates along the reactor reforming the solid fuel inside within a wide-power-range, high-efficiency, high energy concentration per unit of volume and stable combustion over a wide range of equivalence ratios [23]. Several experimental studies on HFC for syngas and H2 production have been conducted [24–35], showing that the technology presents a strong and feasible option for syngas production from gaseous and solid fuels in a

In [24] three types of algae were analyzed, showing that an increase of volume algae fraction in the hybrid bed and an increase of moisture content in the algae used increased both combustion temperature and hydrogen yields. Different gasifying agents were used on experiments with biomass pellets and alumina spheres using equal volumetric fractions [25]. While operating with natural gas (NG), the combustion wave temperature increased only using insignis pine, whereas the usage of cereal plantation residuals enhanced the syngas production. Using steam, the combustion wave temperature presented a slight decrease as the steam presence increased. In the case of natural gas in a porous medium composed of coal and alumina particles [26], the flame temperature decreased with an increase of coal fraction, and hydrogen and carbon monoxide were dominant partial oxidation products. Further experimental studies [29, 31] consistently reported that hydrogen and carbon monoxide are dominant partial oxidation products for atmospheric

Industrial applications of HFC have been successfully implemented in Northern-

**Figure 1** shows the experimental setup generally used in hybrid porous media reactors. The filtration combustion system consists of a tube, usually made of quartz, filled with uniformly mixed aleatory ceramic spheres and solid fuel particles. To compensate for the different thermal expansion rates of the packed bed and tube, the inside diameter of the tube is covered with an insulation blanket (ceramic fiber). Heat losses due to conduction through the tube wall are minimized with an additional insulation layer covering the outside of the tube. Air, fuel, and/or steam, metered using mass flow controllers, are premixed before entering the reactor and introduced into the reactor from its bottom. The upstream or downstream propagating combustion wave is ignited using a lighter at the reactor exit or reactor bottom. System diagnostics are required to assess the temperature profile in the reactor and the chemical composition of the output gases. The axial temperature distribution of the reactor is measured by thermocouples. These thermocouples are housed in a multi-bored ceramic shell. A data acquisition system is used to read and record the temperatures. The digital conversion of the resultant analog signals is performed with a data acquisition board. Finally, the chemical composition of the

European countries, such as Finland and Russia, where two reactors capable of processing up to 15,000 ton/yr of municipal solid wastes (MSW) were engineered by the IPCP-RAS (Russia) and developed by Europrofile Ltd. in Lappeenranta

**3. Experimental results by hybrid filtration combustion**

*DOI: http://dx.doi.org/10.5772/intechopen.88795*

configurations.

batch configuration.

hybrid combustion waves.

(Finland) and Moscow (Russia) [36, 37].

flue gases is measured using a gas chromatograph.

#### *Syngas Fuel Production from Carbonaceous Feedstocks Using Hybrid Porous Media DOI: http://dx.doi.org/10.5772/intechopen.88795*

The common approaches to use the technology are the stationary and transient configurations.

A relation between IPM combustion and solid fuel gasification converges into hybrid filtration combustion (HFC), a process that combines the properties of the aforesaid processes by replacing a fraction of the inert solid's volume with a solid fuel. In this case, a reaction wave is produced by a flow that can contain hot air, H2O(g), or a gaseous fuel-air mixture that propagates along the reactor reforming the solid fuel inside within a wide-power-range, high-efficiency, high energy concentration per unit of volume and stable combustion over a wide range of equivalence ratios [23]. Several experimental studies on HFC for syngas and H2 production have been conducted [24–35], showing that the technology presents a strong and feasible option for syngas production from gaseous and solid fuels in a batch configuration.

In [24] three types of algae were analyzed, showing that an increase of volume algae fraction in the hybrid bed and an increase of moisture content in the algae used increased both combustion temperature and hydrogen yields. Different gasifying agents were used on experiments with biomass pellets and alumina spheres using equal volumetric fractions [25]. While operating with natural gas (NG), the combustion wave temperature increased only using insignis pine, whereas the usage of cereal plantation residuals enhanced the syngas production. Using steam, the combustion wave temperature presented a slight decrease as the steam presence increased. In the case of natural gas in a porous medium composed of coal and alumina particles [26], the flame temperature decreased with an increase of coal fraction, and hydrogen and carbon monoxide were dominant partial oxidation products. Further experimental studies [29, 31] consistently reported that hydrogen and carbon monoxide are dominant partial oxidation products for atmospheric hybrid combustion waves.

Industrial applications of HFC have been successfully implemented in Northern-European countries, such as Finland and Russia, where two reactors capable of processing up to 15,000 ton/yr of municipal solid wastes (MSW) were engineered by the IPCP-RAS (Russia) and developed by Europrofile Ltd. in Lappeenranta (Finland) and Moscow (Russia) [36, 37].
