Gas Permeabilities

Previous core flooding studies have concentrated on the squeezing of scale inhibitors into oil reservoirs where the system is 2-phase (brine and crude) and considers the interactions of these fluids with reservoir core substrate under reservoir conditions. The core floods are generally up to temperatures of 150°C with a line pressure of up to 1,000 psi and a confining pressure of up to 2,000 psi, although recently the maximum pressure and temperature rating of the core floods has been increased.

The rig was then further modified to apply scale inhibitor squeeze treatments in gas production wells at high temperature and to measure very low differential pressures (< 0.2psi). The systems were equipped with two 1,000 ml Hastelloy vessels that permit the delivery and collection of gases. Commissioning tests to ascertain that the system could make stable permeability measurements were carried out using the Clashach core at 20°C and 100°C with a line pressure of 200 psi and 3,000 psi (confining pressure of 2,000 psi and 4,000 psi respectively). Nitrogen was used to determine the gas permeability and synthetic seawater used to determine brine permeability.