Topical Report: Task 1.4 Correlation of Capillary Suction Time with Leak-Off Behavior

Hoff, Tatiana ; Growcock, Fred

MASI Technologies LLC

关键词: Drilling Fluids;    42 Engineering;    02 Petroleum;    Materials Testing;    Measuring Methods;   

DOI  :  10.2172/896522
RP-ID  :  None
RP-ID  :  FC26-03NT42000
RP-ID  :  896522

美国|英语

来源: UNT Digital Library

【 摘 要 】

Core Leak-off tests are commonly used to ascertain the ability of a drilling fluid to seal permeable rock under downhole conditions. Unfortunately, these tests are expensive and require a long time to set up. To monitor fluid invasion trends and to evaluate potential treatments for reducing fluid invasion on location, a simpler screening test is highly desirable. The Capillary Suction Time (CST) Test has been used since the 1970's as a fast, yet reliable, method for characterizing fluid filterability and the condition of colloidal materials in water treatment facilities and drilling fluids. For the latter, it has usually been applied to determine the state of flocculation of clay-bearing fluids and to screen potential shale inhibitors. In this work, the CST method was evaluated as a screening tool for predicting relative invasion rates of drilling fluids in permeable cores. However, the drilling fluids examined--DRILPLEX, FLOPRO, and APHRON ICS--are all designed to generate low fluid loss and give CST values that are so high that fluid invasion comes to be dominated by experimental artifacts, such as fluid evaporation. As described in this work, the CST procedure was modified so as to minimize such artifacts and permit differentiation of the fluids under investigation.