Dear Olusegun D. Samuel ,

the reaction of pyrolytic oil with oxygen in a combustion chamber is a redox reaction. In a redox reaction electrons are donated by the fuel and accepted by oxygen. The amount of energy liberated can be calculated as follows:

dG = n * F * dE

where n is the number of electrons, F Faradays constant [kJ/V] and dE the difference in reduction potential between two substances [V].

If the fuel is already oxygenated it generally suggests that the amount of electrons that carbon can donate is less. Simple example:

C + O2 --> CO2 (4 electrons are donated by C)

CO + 1/2 O2 --> CO2 (2 electrons are donated by C)

It is also possible to predict the higher heating value (HHV) of bio-oils from 13C NMR for example (Article Prediction of Properties and Elemental Composition of Biomas...

You could give it a go and use the model to predict HHV of your oxygenated fuel and compare it with a non-oxygenated one.

Hope this helps?

There can be nearly more than 40 ways how pyrlysis being done , the celluose degrades rapidly become c02 and water provind energy for pyrolysis , with furans , similar behaviur of cellulose to but levunan aromatics , but the real energy values can be from lignin phenic manomer nano paricles.unlike fuel oil oxygenates , these phenolic are very reactive , thus in bio oil , simillar to tar , asphalt all low valued , even problems in boiler with best combustor

Hi,

As far as I have read about them, these polar compounds do depreciate the value of the biomass pyrolytic oil.

The heating value of a substance depends on its CHO ratio and pyrolysis liquids are typically (wt%, dry liquid basis): C: 56, H:6.2, O: 37 and N: 0.2, S:< 0.01

Water in the liquids cannot be removed physically.

The heating value of pyrolysis liquid can be measured as HHV by DIN 51900. A Parr adiabatic bomb with a Parr Calorimeter Controller 1720 can be employed. The heat of combustion is determined by measuring the temperature increase in the water jacket and then calculated from the energy balance for the system. The high water content of the pyrolysis liquids may lead to poor ignition, and therefore a fine cotton thread can be advantageously used as a wick. The heat content of the thread is subtracted from the result. The lower heating value (LHV) is calculated from HHV and the hydrogen content [ASTM 529192] by equation (1). No subtraction of free water has to be done because the water in the pyrolysis liquid cannot be removed by centrifugation as is the case for heavy petroleum fuel oils.

LHV [J/g] = HHV [J/g] - 218.13 x H% [wt%] (1)

The 40wt% O2 in the liquids does not help, hence the low HHV of about ~17 MJ/kg for liquids containing 30wt% water.