Chapter 3, Problem 1CO

• describe the chemical processes used in biomass production and conversion to biofuels.

Interpretation Introduction

Interpretation: The chemical processes used in biomass production and conversion of biomass to biofuels should be described.

Concept Introduction: In the biomass production, organic materials are converted into some form which can be used to produce bio-energy.

This is defined as increase in the organic matter concentration, this production adds the organic matter in the given area. Biomass is a renewable source of energy as it is obtained from plants and animals waste.

Explanation of Solution

In the biomass production, there are two types of productions as explained below:

Primary production: This is the energy obtained by plants by the process of photosynthesis. The excess energy is stored and added to the total biomass of the ecosystem.

Secondary production: This is defined by the absorption of the organic matter by tissues of the organisms. The ingestion by animals comes under this category. The process involves the decomposition of organic matter with the help of microorganisms.

Now, biomass to biofuel conversion is most important step in the agricultural world. Biomass is referred to the waste like trees, grass and other garden waste in the agriculture. This process can reduce the emission of greenhouse gases in the environment. This also balances the ecology. The process of biomass conversion directly uses the energy and the amount of energy used depends on the technique applied for the conversion.

There are main two types of conversions:

1. Thermal conversion
2. Chemical conversion

Thermal conversion: As the name suggests, in thermal conversion, heat plays an important role in biomass conversion.

This is further divided into three steps:

1. Combustion
2. Gasification
3. Pyrolysis

The first process involved the combustion of biomass, the efficiency of this method of conversion is very low and it also affects the environment.

In gasification, the biomass is heated at very high temperatures in the presence of oxygen but in the controlled amount.

The pyrolysis involves the heating of biomass at very high temperatures in the absence of oxygen.

Chemical conversion: This process uses enzymes and microorganisms for the breakdown of biomass. The sub-processes are as follows:

Anerobic digestion: This converts biomass to methane.

Fermentation: This converts starch to ethanol and used in the manufacturing of alcohol

Composting: In this process, dry organic matter is decomposed aerobically in the presence of microorganisms. This is commonly used to produce heat.