dc.description.abstract | Halite (NaCl) scaling complicates oil and gas production from many reservoirs worldwide because of its facile and fast precipitation in well tubulars or near-wellbore areas. Current industry approaches to remove halite scales via continuous or periodic freshwater treatments are often inefficient or late measures. In this study, a new class of halite scale inhibitors is studied to identify its inhibition efficiency in halite scale with benchmark halite scale inhibitor.
A modified and improved static bottle test is used. The experimental procedure is optimized for dissolving 37.50g of NaCl in 100 mL of distilled water at 80°C. After dosing inhibitor into bottle, brine is heated in an oven to ensure complete dissolution of NaCl. Solution is then kept in a switched-off oven to gradually cool down to 23°C for the following 36 hours. Precipitated halite crystals are collected, if any, then dried, and weighed. Certain experiments are performed in duplicate to assess the reproducibility of the results.
Ten out of eighteen inhibitors tested in this study have completely inhibited halite scale growth. The inhibition efficiency of effective inhibitors is 100%. More importantly, these additives are safe for the environment since most of them are food additives. In the field, these effective inhibitors not only reduce the frequency of freshwater treatments but also increase the revenue for operators by minimizing production downtime and freshwater cost.
This study introduced a new class of inexpensive and efficient halite scale inhibitors. Field application of these products will minimize the problems associated with halite scale deposition and freshwater treatments. | |