Adsorption Isotherm for Coals and Shale

ERC conducts adsorption isotherm analysis on coal and shales for the purpose of determining gas storage capacity by adsorption at reservoir temperature and pressure conditions. Samples (single or composite) are analysed on an equilibrium moisture basis but other moisture bases can be used as required. The range of gases for which adsorption characteristics can be determined include methane (CH4), ethane ( C2H6), propane (C3H8), carbon dioxide (CO2) and nitrogen (N2). Absolute or excess adsorption can be determined. Gas saturation and critical desorption pressure can be calculated, which are critical parameters in coal bed methane (CBM) targets. Adsorption data can be modelled using Langmuir, BET, Dubin-Astakhov (D-A),Dubin-Radushkevich (D-R) as well as utilising extended Langmuir modelling for mixed gases. Results are reported to industry best practise in standard reports . Coal property (moisture content and ash yield) analysis is always carried out in conjunction with adsorption isotherm analysis. Petrography is usually carried out in conjunction with the adsorption isotherm test work.

Example of ERC adsorption Isotherm reporting