**3.3 The yield of syngas**

The syngas yield is measured by the mass of the produced in cubic meters per the mass of the feedstock provided to the system The yield is directly commensurate with the difference in ER and with the gas residence time in the reduction area [9]. The biomass ash content also has a considerable impact and limits the yield of the gas producer.

**27**

*Syngas Production, Properties, and Its Importance DOI: http://dx.doi.org/10.5772/intechopen.89379*

**3.4 Cleaning and cooling of producer gas**

**4. Fischer-Tropsch diesel production**

absorption, desorption, and compression.

active sites accompanying the main reaction (Eq. (4)).

fuel production.

**Figure 2.** *The gasificator [8].*

chemicals [8].

processing and easy to use.

Original FT reaction:

The combustible gas can be used as a feedstock for the production of chemicals

One of the commercially accessible methods of manufacturing clean synthetic fuel from syngas is Fischer-Tropsch technique. Industrially speaking, coal/pet-coke/ biomass emits huge quantities of carbon dioxide that can be used to enhance the

Because of the increased level of carbon dioxide in atmosphere and also the depletion of conventional fuels, scientific researches recommend the chemical

The production of synthetic fuel from syngas is favorable process owing to its portability as well as to its large quantity of chemical energy, saved without further

The raw syngas undergoes multiple energy intensive processes to fulfill the stoichiometric requirements (2.05 < H2/CO < 2.15) for Fischer-Tropsch, including removal of carbon dioxide for subsequent sequestrating, to mitigate negative carbon dioxide emission impacts. Absorption techniques with mono- and diethyl amines are the most popular technology for the removal of carbonic gases from syngas. These procedures are energy intensive owing to the intermediate steps of

The main Fischer-Tropsch reaction is to produce aliphatic long-chain saturated hydrocarbons from syngas (Eq. (3)). There are a lot of side reactions that occur on

nCO + 2nH2 → (CH2)n + nH2O;ΔH298 K = −152 kJmol−1 (3)

recycling of carbon dioxide into renewable fuel and more added-value

like methanol or in internal combustion engines for direct heat uses.

*Syngas Production, Properties, and Its Importance DOI: http://dx.doi.org/10.5772/intechopen.89379*

*Sustainable Alternative Syngas Fuel*

By-products: tar, char, ashes.

The reaction also can be expressed as:

• High temperature (800–1000°C) and low pressure (1–20 bar)

• H2/CO ratio within 0.5 and 1.8, depending on the technologies

CaHbOcNd + O2/ H2O/ N2 → CO + H2 + CxHyOz + CO2 + H2O + NH3 + N2 (2)

× 100

/s), Hs is the lower heating

where ηm is the gasification efficiency (%) (mechanical), Hg is the heating

value of gasifier fuel (kJ/kg), and Ms is the gasifier solid fuel consumption (kg/s).

The syngas yield is measured by the mass of the produced in cubic meters per the mass of the feedstock provided to the system The yield is directly commensurate with the difference in ER and with the gas residence time in the reduction area [9]. The biomass ash content also has a considerable impact and limits the yield

), Qg is the volume flow of gas (m3

The solid carbon is partially oxidized with oxygen (O2), air, steam (H2O), or a combination of all gasification agents. CxHyOz is mostly made of methane with a few low percent of hydrocarbon, including ethane and ethylene (**Table 1**). For most gasifiers, gas may also contain heavier hydrocarbons such as benzene, toluene, and naphthalenes, depending on the feedstock and the operational parameters. Hydrocarbons, which are heavier than benzene, are often known as tars (**Figure 2**). This is an important factor in determining the technical mechanism and the economic feasibility of the gasification system. Efficiencies in gasification are based on the biomass type used, its particle size, its ER value, and the reactor design [8]. The gasification efficiency is usually determined on the lower heating value basis. The efficiency is calculated as the ratio of the total energy in the producer gas (sensible and chemical) and the chemical energy in the feedstock (the heating value). Depending on type and design of the gasifier as well as on the characteristics of the fuel, mechanical gasifier efficiency may vary between 60 and 75%. A useful definition of the gasification efficiency (%) used for engine applications is as follows: ηm = \_ Hg × Qg Hs × Ms

Reaction conditions:

*Composition of producer gas [8].*

**Table 1.**

**26**

value of the gas (kJ/m3

**3.3 The yield of syngas**

of the gas producer.

### **3.4 Cleaning and cooling of producer gas**

The combustible gas can be used as a feedstock for the production of chemicals like methanol or in internal combustion engines for direct heat uses.
