- Industry: Oil & gas
- Number of terms: 8814
- Number of blossaries: 0
- Company Profile:
A common well-intervention operation involving a wide variety of mechanical scale-inhibitor treatments and chemical options. Mechanical removal is done by means of a pig or by abrasive jetting that cuts scale but leaves the tubing untouched. Scale-inhibition treatments involve squeezing a chemical inhibitor into a water-producing zone for subsequent commingling with produced fluids, preventing further scale precipitation. Chemical removal is performed with different solvents according to the type of scale:<br><br>路 Carbonate scales such as calcium carbonate or calcite (CaCO<sub>3</sub>) can be readily dissolved with hydrochloric acid (HCl) at temperatures less than 250<sup>o</sup>F (121<sup>o</sup>C). <br>路 Sulfate scales such as gypsum (CaSO<sub>4</sub>路2H<sub>2</sub>O) or anhydrite (CaSO<sub>4</sub>) can be readily dissolved using ethylenediamine tetraacetic acid (EDTA). The dissolution of barytine (BaSO<sub>4</sub>) or strontianite (SrSO<sub>4</sub>) is much more difficult. <br>路 Chloride scales such as sodium chloride (NaCl) are easily dissolved with fresh water or weak acidic solutions, including HCl or acetic acid. <br>路 Iron scales such as iron sulfide (FeS) or iron oxide (Fe<sub>2</sub>O<sub>3</sub>) can be dissolved using HCl with sequestering or reducing agents to avoid precipitation of by-products, for example iron hydroxides and elemental sulfur. <br>路 Silica scales such as crystallized deposits of chalcedony or amorphous opal normally associated with steamflood projects can be dissolved with hydrofluoric acid (HF).
Industry:Oil & gas
A complete section of a conventionally drilled core. The section may be up to about 2 feet (0. 6 m) in length, with typical core diameters lying between 1. 75 and 5. 25 in. (4. 4 and 13. 3 cm). The term full-diameter core is also used, but generally refers to shorter sections of about 6 in. (15 cm). The advantage of whole core analysis is that it measures properties on a larger scale, closer to that of the reservoir. This is particularly important for heterogeneous formations such as many carbonates or fractured materials.
Industry:Oil & gas
A completion component that is used to house gas-lift valves and similar devices that require communication with the annulus. The design of a side-pocket mandrel is such that the installed components do not obstruct the production flow path, enabling access to the wellbore and completion components below.
Industry:Oil & gas
A completion component, generally included in the lower assembly near the packer, that allows communication between the tubing and annulus. Circulation devices enable the circulation of fluids for well control or kickoff purposes.
Industry:Oil & gas
A completion configuration in which a production casing string is set across the reservoir interval and perforated to allow communication between the formation and wellbore. The casing performs several functions, including supporting the surrounding formation under production conditions, enabling control of fluid production through selective perforation and allowing subsequent or remedial isolation by packers, plugs or special treatments.
Industry:Oil & gas
A completion design in which the reservoir fluids are produced through small-diameter casing. The absence of a separate tubing string significantly limits the operating and contingency options available for the well.
Industry:Oil & gas
A completion device that can be operated to provide a flow path between the production conduit and the annulus. Sliding sleeves incorporate a system of ports that can be opened or closed by a sliding component that is generally controlled and operated by slickline tool string.
Industry:Oil & gas
A completion or workover fluid that has been treated to remove debris and fine particles that may cause near-wellbore damage if allowed to enter the reservoir formation.
Industry:Oil & gas
A completion system designed to utilize the natural flow capability of the reservoir.
Industry:Oil & gas
A completion that utilizes coiled tubing as the production conduit, or as a means of conveying and installing completion equipment or components. Since the coiled tubing string is continuous, problems associated with connections are avoided. Also, the pressure-control equipment used on coiled tubing operations enables work to be safely conducted on live wells.
Industry:Oil & gas
