Horizontal Screen Failures in Unconsolidated, High-Permeability Sandstone Reservoirs: Reversing the Trend

Abstract

Horizontal screen failures can be serious, resulting in expensive remedial operations including early abandonment, in the extreme case. Globally, screen failures in horizontal wells completed in loose unconsolidated sandstone reservoirs have become common. Consequently, from completion and longevity perspectives, a high percentage of horizontal wells have not achieved the desired result: sand-free, high sustained-productivity producers. Individual companies have performed studies in this direction, and some are still ongoing. From preliminary data available, however, it has been possible to observe trends and determine the failure mechanisms. Failure categories highlighted in this paper include wells with significant impaired productions or those completely plugged, representing an overall failure rate of almost 20%. This paper suggests several levels of screen failure: screen collapse or complete plugging, partially plugged screens (poor performing wells) and those producing unacceptable amounts of sand. Other failures include improper installation and economic failures where fixing the problem is possible but costly. Some wells exhibited "early mortality " producing sand at production onset. The study further categorized possible causes of screen failures into three major areas:Screen plugging caused by high-pressure drops across screens, hot spots of localized production, fines and dirty sand.Incorrect procedures, materials or equipment selection including trouble installing the screens, corrosion in low spots due to standing acid, generalized corrosion from acids, improper cleanup, ineffective mud removal, ineffective sand control, inappropriate screen selection and erosion.Poor reservoir understanding in the areas of grain size distribution, sanding up due to water production, open annular areas due to higher than expected rock strength. This paper reviews various applications of soft rock completions in horizontal service, along with benefits and shortfalls. The performance characteristics of the various screens relative to each other from the perspective of flow capacity, plugging and erosion resistance are examined. Recommendations based on "best practices " being adopted to combat screen failure problems in high permeability reservoirs are also showcased. Introduction Screens deployed in horizontal wells provide means of sand control for most of horizontal reservoirs.Horizontal screen failures can be serious, resulting in expensive remedial operations including early abandonment, in the extreme case. A typical screen failure manifests as an opening in the screen that is larger than the design value, permitting large particles from the formation to pass through them. The consequence is excessive sand production and loading of the bore hole with sand and eventually cutting off production (Fig. 4,5 & 6). High costs of separation, treatment and disposal could then make the well economics unfavorable. Apart from the economic impact, safety and environmental concerns (sand disposal) are becoming more critical as sand production increases. It is therefore in order to study various screen failures and make recommendations based on "best practices ' ' that have been adopted to combat screen failure problems in high permeability reservoirs. Various designs of screens have been employed in wells for sand control in unconsolidated high permeability sandstone reservoirs. Commonly used screen types are wire wrap screens, slotted liners, pre-packed screens and premium screens like the Excluders or Strata Pac.

Sand screens application and performance for sand control: A review of selection criteria, screen materials, and causes of failure

“…Many authors have examined causes and failure modes of SAS. Most of these studies concluded that screen erosion is by far the most common failure mechanism [ [58] , [59] , [60] ]. Screen erosion is due to the mechanical wear of the retention media, weave or wire.…”

Optimization of calcium carbonate precipitation during alpha-amylase enzyme-induced calcite precipitation (EICP)

“…Biostabilization has lately emerged as a sustainable option capable of overcoming some of the limits of traditional soil improvement techniques (Umar et al, 2016;Rahman et al, 2020;Xue et al, 2023). Efforts are being made in soil stabilization by adapting bacteria to enhance soil performance (Banik et al, 2023;Sharma and Satyam, 2023). Enzyme-induced calcite precipitation (EICP) is a promising approach due to its simplicity of application in the field and compatibility across various types of soil (Saif et al, 2022).…”

“…In comparison to chemical methods, mechanical techniques are typically more expensive and time-consuming ( ben Mahmud et al, 2020 ). They also face other issues like a decline in productivity index, complicated installation equipment, installation-related damage, workover difficulties, zonal isolation issues, collapsed screens, and equipment erosion and plugging ( Arukhe et al, 2005 ; Abduljabbar et al, 2022 ). Additionally, they are useless at containing tiny sand particles.…”