Reza Daneshfar - PhD Student in Petroleum Engineering at Petroleum University of Technology, Ahwaz, Iran
Jamshid Moghadasi - Associate Professor at Petroleum University of Technology, Ahwaz, Iran
Seyed Mojtaba Bassir - PhD Student in Petroleum Engineering at Petroleum University of Technology, Ahwaz, Iran
Peyman Kamranfar - PhD Student in Petroleum Engineering at Petroleum University of Technology, Ahwaz, Iran

In this paper the shale hydration inhibitive properties of various materials in drilling fluid system were compared by different experiments that was done by researches over last years. Some of these materials are include polyether diamine (PEDA), formates, polyethyleneimine (PEI), potassium chloride (KCl), amine-tartaric salts (ATS), KCl/partial hydrolytic polyacrylamide (PHPA), KCl/graphene nanoplatelet (GNP), KCl/nanosilica, KCl/multi-walled carbon nano tube (MWCNT), bis- (hexamethylene)- triamine, 4, 4’-methylenebis-cyclohexanamine, polyoxyalkyleneamine (POAM), and poly(oxypropylene)-amidoamine (POAA). In the most investigatins, comparisons were done between two or more materials through bentonite inhibition tests, shale hot-rolling dispersion tests, bulk hardness test and particle distribution tests. The inhibitive mechanism of material was analyzed via zeta potential measurement, X-ray diffraction analysis, modified montmorillonite water adsorption test, activity test, isothermal adsorption, adsorption kinetics, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), elemental analysis (EA), cation exchange capacity (CEC), thermogravimetric analysis (TGA), surface tension analysis, transmission electron microscope (TEM), and linear expansion experiments. Electrostatic interaction, hydrogen bonding and hydrophobic shielding effect contributed to the inhibition mechanisms of clay swelling inhibitors. As these compartions were done between two or more materials, there is no same rule to say which of these materials are the best but these compartions are very instructive.

shale hydration, formation damage, inhibitors, drilling fluid, swelling