PHYLLIS

Definitions used in Phyllis

Proximate analysis:

Ash:
Ash content expressed in weight % on dry base (dry) and on as received material. Through the water content the ash contents are related:
Ash content (wt% dry) = ash content (wt% ar) * 100 / (100 - water content (wt%))

Water content:
Water content in weight %, on wet base (as received). It is important to note that there can be a large difference between the water content of the material as it is available and the water content at the moment of analysis. Also by natural drying during storage the water content can be lowered.

Volatiles and fixed carbon:
The amount of volatile material is determined by standardised methods. The amount of volatiles is expressed in weight % dry material, as received material or dry and ash free material.
The amount of fixed carbon is calculated as the remaining part as determined by the above mentioned standardised method according to the following formulas:

Ultimate analysis:

Carbon (C), hydrogen (H), oxygen (O), nitrogen (N), sulphur (S), chlorine (Cl), fluorine (F) and bromine (Br) content in weight % dry material (wt% dry), dry and ash free material (wt% daf) and on as received material (wt% ar).

In many cases the oxygen content is not measured but calculated as the difference between 100 and the measured components. When the oxygen content is measured the total sum usually does not equal 100 due to experimental errors in the analysis. For each component it is indicated whether it is measured or calculated.

Calorific value (kJ/kg):

The calorific value is expressed as Higher Heating Value (HHV) and Lower Heating Value (LHV). The difference is caused by the heat of evaporation of the water formed from the hydrogen in the material and the moisture:

The determination of the calorific value normally results in a value for the HHV. For comparison, HHV is also calculated from the elemental composition using the Milne formula:

HHV_Milne = 0.341·C + 1.322·H - 0.12·O - 0.12·N + 0.0686·S - 0.0153·ash,

where C, H, etc. are the mass and the ash fractions in wt% of dry material and HHV the heating value in MJ/kg.
By using the hydrogen and ash fractions (wt% dry) and moisture fraction w (wt% ar) the different HHV's and LHV's can be calculated.

HHV_ar = HHV_dry ·(1-w/100)
HHV_dry = HHV_daf ·(1-ash/100)
LHV_dry = HHV_dry - 2.442·8.936 H/100
LHV_ar = LHV_dry ·(1-w/100) -2.442·w/100
LHV_ar = HHV_ar -2.442·{8.936 H/100 (1-w/100) + w/100}

Ash composition (wt% ash):

A large number of data on the ash composition after conversion is available. In general these data are expressed as weight % of oxides. The selected oxides are not representative for the actual chemical form of the components.
Lead (Pb), cadmium (Cd), copper (Cu), mercury (Hg), manganese (Mn) en chromium (Cr) are expressed in mg/kg ash.

Biomass analysis (mg/kg dry):

The metal content is expressed in mg/kg dry (original) material. For each element is it shown whether it is measured or the value is below the detection limit.

Biochemical composition (wt%):

The biochemical composition of materials is expressed in weight % of the dry material (cellulose, hemi-cellulose, lignin, fats, protein, pectin, starch, extractives, C5 and C6 sugars, total non-structural; carbohydrates). If sugar analysis is applied, cellulose = glucan and hemicellulose = sum C5 + sum C6 - glucan - rhamman.