An Improved Method for Grinding and Reinjecting of Drill Cuttings

Abstract

An Improved Method for Grinding and Reinjecting of Drill Cuttings Gunnar Sirevag; Gunnar Sirevag Statoil A/S Search for other works by this author on: This Site Google Scholar Arthur Bale Arthur Bale Statoil A/S Search for other works by this author on: This Site Google Scholar Paper presented at the SPE/IADC Drilling Conference, Amsterdam, Netherlands, February 1993. Paper Number: SPE-25758-MS https://doi.org/10.2118/25758-MS Published: February 22 1993 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Sirevag, Gunnar, and Arthur Bale. "An Improved Method for Grinding and Reinjecting of Drill Cuttings." Paper presented at the SPE/IADC Drilling Conference, Amsterdam, Netherlands, February 1993. doi: https://doi.org/10.2118/25758-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE/IADC Drilling Conference and Exhibition Search Advanced Search SPE and IADC MembersAbstractA successful reinjection of oil-wet drill cuttings has been performed on the Norwegian Gullfaks Field. The reinjection was carried out in the annulus between two casing strings through a wear-protected wellhead. An effective way of grinding cuttings and mixing slurry by use of a new patent pending method known as SMACCC - Statoil Method for Autogenous Crushing and Classifying of Cuttings has been developed.The paper discusses reservoir aspects and presents simulated fracture geometries as a result of rock mechanical and slurry in-put property data. Further, the paper describes a 1000 hour wear test, involved equipment, and gives a derived formula describing wear from sand slurries on internal wellhead components.IntroductionThe basic background to the cuttings reinjection project wasStatoil's environmental policy to cause the least possible pollution of the environment, andthe company's policy to develop technologies and concepts meeting low crude prices.The increasing demand for highly deviated and longer wells currently necessitates the use of oil-based mud, which is neither permitted to be discharged into the sea nor to be burned. With newly realized environmental concerns, about disposal problems for drill cuttings and drilling solids residue for oil based mud systems, several new disposal methods are currently being considered and investigated by the oil industry.Since 1988, Statoil has reduced the use of oil-based mud by about 95% on the Gullfaks Field. The project of reinjecting cuttings, waste mud and oily waste water from drilling was a following-up project to virtually eliminate the discharge of oily waste from Statoil's drilling and production platforms. As of November 1st 1992, a total of 6500 Sm (40880 BBL) of waste drilling fluids and cuttings have been reinjected into shallow formations on the Gullfaks Field. Reinjection of cuttings by use of the new crushing and mixing system is now planned on several Statoil platforms in the North Sea.This paperdiscusses simulated reservoir and rock mechanical data together with fluid/slurry properties in conjunction with down-holedisposal operationsdescribes a 1000-hour combined wellhead and centrifugal pump sand erosion test. An equation relating erosion to velocity and sand concentration is given.describes the size and capacity of the new SMACCC system, including an improved and wear-resistant centrifugal pumppresents actual field test data and performance analyses for offshore disposal operationsRESERVOIR MODELLING AND SIMULATION RESULTSGeneral ConsiderationsSubsurface injection is a world wide common method of waste disposal, and many injection wells have been operating for years with massive volumes of material being injected. The major difference between such "normal" disposal operations and disposal of drilling cuttings and impure mud is the high percentage of solids to be injected, with the corresponding requirement for injection above fracture closure pressure - e.g. it will be necessary to open and probably extend hydraulic fractures and/or open and extend existing natural fractures.P. 773^ Keywords: centrifugal pump, operation, slurry, permeable formation, disposal, gradient, gunnar sirevag, vertical fracture, wellhead, drilling fluid formulation Subjects: Drilling Fluids and Materials, Hydraulic Fracturing, Drilling fluid selection and formulation (chemistry, properties) This content is only available via PDF. 1993. SPE/IADC Drilling Conference You can access this article if you purchase or spend a download.