NOTE: This item is not available outside the Texas A&M University network. Texas A&M affiliated users who are off campus can access the item through NetID and password authentication or by using TAMU VPN. Non-affiliated individuals should request a copy through their local library's interlibrary loan service.
Experimental study of zone isolation in horizontal wells using a new straddle-chemical-wellbore-plug system
MetadataShow full item record
This research constitutes part of phase II of a joint industry project aimed at investigating the feasibility of sealing off water and gas producing zones in a horizontal well. This research is a follow-up from an earlier joint industry project (phase 1) to study the use of chemical wellbore plugs for zone isolation.' The earlier experiments were conducted using PVC pipes up to 2-in. diameter and 3-ft. length. The encouraging results from these earlier experiments led to testing the method in a full-scale 60-ft. long by 6-in. diameter wellbore model. The new method consists of four sequential stages: (i)Setting a chemical wellbore plug in the horizontal section just upstream of the problem zone. (ii)Setting a second chemical wellbore plug in the horizontal section downstream of the problem zone. (iii)Spotting and squeezing a low viscosity formation gel between the straddle wellbore plug system into the problem zone. (iv)Washing out excess formation gel and wellbore plug to clean the borehole prior to production. The . job would be carried out using coiled tubing and only one round trip would i be necessary. The objective of this research is to investigate the feasibility of the new straddle-chemical-wellbore-plug system using a full-scale horizontal wellbore model subjected to a reservoir temperature of 120 OF. Two chemicals, namely K-MAX and PERMSEAL were used, and in the experimental run, a 40-ft. long chemical wellbore plug (K-MAX) was set, followed by injection of formation gel (PERMSEAL) into a 20-ft. zone. From symmetry, the system represented an actual straddle chemical plug pair, each up to 40-ft. length and a 40-ft. zone into which formation gel is injected. Based on results from the first run, the new straddle-chemical wellbore-plug system appears to be a viable method. The chemical plug sealed the pre-perforated liner/sand-screen annulus completely off, and the formation gel had penetrated the sand, making it very consolidated and impermeable. These initial results indicate great promises for the new straddle-chemical-wellbore-plug system. Further experimental runs are however required to fully test and optimize the new zone isolation technique.
DescriptionDue to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to email@example.com, referencing the URI of the item.
Includes bibliographical references: p. 79-83.
Issued also on microfiche from Lange Micrographics.
Lilledal, Lars Ove (1998). Experimental study of zone isolation in horizontal wells using a new straddle-chemical-wellbore-plug system. Master's thesis, Texas A&M University. Available electronically from
Request Open Access
This item and its contents are restricted. If this is your thesis or dissertation, you can make it open-access. This will allow all visitors to view the contents of the thesis.