Biomass charaterisation

Biomass is very much different from biomass produce from different places. Charaterisation of biomass very important to get best possible processing strategy for production of range of fuels, also to understand how easy is it to produce, collect, store, transport, and process (crop yield, economics, equipment availability, grinding performance, etc.). 

To charaterise the biomass, we need study the combustion properties of biomass which includes that all properties of biomass.

Combustion properties of biomass:

Macroscopic

1. Ultimate analysis, 
2. Heating value, 
3. Moisture content, 
4. Particle size, 
5. Bulk density, 
6. Ash fusion temperature.

Microscopic

1. Thermal kinetic,
2. Chemical kinetic, 
3. Mineral data.

Proximate analysis gives the complete information of biomass’s moisture content, volatile matter, fixed carbon and ash. Now-a-days proximate analysis is carried out using thermo-gravimetric analysis (TGA) equipment, in which controlled heating mechanism is available. In TGA very small amount of sample is required nearly 1-20 milligram. Heating rates suggested for moisture analysis of biomass is ambient temperature to 120 °C and hold isothermal for 1 hour. For Volatile matter, heating the biomass from 120 °C to 500 °C and hold isothermal for 1 hour in presence of inert atmosphere (Nitrogen). For ash content, inert atmosphere is replaced with oxygen atmosphere where oxidation of biomass takes places and leaving behind the ash which is inorganic matter. Fixed carbon is calculated from difference of moisture content, volatile matter and ash.

Ultimate analysis is based on the elements that make up the biomass, typically including carbon, hydrogen, oxygen, nitrogen, sulfur, and chlorine. Now-a-days sophisticated instruments are for elemental analysis of biomass, namely CHNOS analyzer. They work on principle of gas chromatography in which elements are detected in their oxide form, and nitrogen as it is.