Survey and Data Analysis of Weak Gel Treatments in Injection Wells

摘要

Excessive water production is a major concern in mature reservoirs. Weak gels have been applied in injection wells for in-depth profile modification. However, the data range and distribution of each parameter that affects performance of weak gels have not been studied thoroughly.;China has the largest amount of chemical-based conformance control treatments. This paper presents a summary of comprehensive data ranges and distributions for weak gel treatments based on the laboratory experiments and field applications in China from 2001 to 2010. The data set includes 76 cases compiled from China Academic Journals papers. In this study, reservoir properties, gel properties and production data are specifically studied with statistical analysis methods. Box plots and histograms are used to display the range and distribution of each parameter and bar charts and cross plots are used to show comparisons among different categories, such as polymer type and crosslinker type.;Based on statistical analysis, HPAM is more widely used over broad ranges of temperatures and brine salinities in China, although other polymers, such as AP and KYPAM, have better stabilities in severe conditions (high temperature or high salinity). For crosslinkers, chromium(III) crosslinkers and phenol-formaldehyde crosslinkers are more widely used in China, and phenol-formaldehyde crosslinkers are more widely used over a broad range of temperatures, from low to high temperatures, although they are normally designed for high temperature applications.