SPE's publication for the Projects, Facilities, and Construction (PFC) technical discipline, Oil and Gas Facilities (OGF), has recently launched a monthly section which will feature synopses of editor-picked SPE technical papers on PFC topics. OGF Selection Editor Gerald Verbeek will pick three papers each month that are then synopsized by SPE editorial staff and published on the OGF website. Verbeek was previously the executive editor for peer-reviewed papers in OGF and was recognized as "A Peer Apart" honoree for peer-review of more than 100 technical papers. He has picked Corrosion and Scaling for the first selection, a topic that affects all involved in oil and gas facilities. "Early in my career I spent about a year as a corrosion engineer to learn the fundamentals, only to discover that without keeping scaling and corrosion in mind, it is impossible to a be a good facilities engineer," said Verbeek in his introductory article about the new section.
Over 20 percent of major oil and gas (O&G) incidents reported within the European Union (EU) since 1984 have been associated with corrosion under insulation (CUI) [
Using bayesian networks (BNs) Oceaneering has developed a decision support system for effective CUI risk management. The Bayesian model can be incorporated into existing risk-based assessment (RBA) systems. A key feature of the model is the ability to predict corrosion hotspots while quantifying uncertainties. The model uses probabilities based on objective data as well as subject matter expertise, which makes analytical techniques in business accessible to a wide range of users.
With a case study we illustrate how BNs can be used to assess the risk of a fuel gas line on a live asset in the North sea. The most likely estimated remaining life (ERL) is forecasted in the range of 13 to 24 years, with a worst case of 6.7 years and best case of 40 years. By comparison, the customer CUI tracker reported an ERL of 9.7 years. BNs increase flexibility for scheduling inspection intervals, enabling more targeted inspection planning. This is a significant advancement from current RBA methodologies.
Microbial-influenced corrosion (MIC) has been implicated in few corrosion-related challenges in the well-service industry in the past. DuPont is ramping up the commercial-scale implementation of its microbial enhanced oil recovery (MEOR) method after nearly a decade of development and testing of what it says is a low-risk way to improve production from mature fields.
This course will help attendees develop the awareness of the cost of corrosion and how it can be managed and mitigated. It teaches the skills of dealing with chemicals, techniques to evaluate their performances, chemical applications and design to control corrosion. It will also help attendees learn corrosivity monitoring and the efficiency of the treatment. This course will help broaden your general knowledge around oilfield corrosion and its impact and control options. Participants will familiarize themselves with the various lab techniques used for evaluation of corrosion inhibitors.
Corrosion inhibitors are often the first line of defense against internal corrosion, and effective mitigation relies on proactive monitoring and management of these inhibitors to allow for regular feedback and dose adjustment. This paper describes a novel method of chemical dosage based on time-resolved fluorescence (TRF) that allows a simple, accurate, and efficient quantification of chemicals below parts-per-million ranges, even for double (scale/scale, scale/corrosion) quantification. A study done to find the root cause of coiled tubing string failures in Montney indicated microbial-induced corrosion, leading the CT service provider to create a biocide treatment program. Rigless coiled-tubing-unit (CTU) interventions can be effective in returning to production wells that have lost electrical-submersible-pump (ESP) efficiency because of organic, inorganic, or mixed scale deposits. Sour gas is being produced from a number of carbon-steel-completed wells in the US, Canada, France, and Saudi Arabia.
This paper reviews the mechanisms of initiation and the prevention of top-of-the-line corrosion (TLC). Recent research and developments are highlighted and validated to arrive at best practices for control of this significant corrosion manifestation. Water condensation and/or hydrate formation at the top of pipelines are serious design/operation considerations in pipelines. This paper reports the results of tests conducted in a new experimental setup constructed for investigating gas-hydrate risks in varied operational scenarios.
Corrosion downhole in oil and gas wells and surface equipment constructed from carbon steel, generally occurs due to the presence of acidic gases (H2S and CO2) or organic acids in the production streams. In addition, solids can cause erosion-corrosion of downhole tubulars and surface pipework if sufficient gas or liquid velocity exists. Surface or topsides pipework and separation equipment can also suffer from corrosion due to bacteria activity. To control downhole and surface corrosion, several technologies are available including corrosion resistant alloys, coatings, biocides, H2S scavengers, and corrosion inhibitors. This session will discuss key lessons learnt in mitigating corrosion and erosion-corrosion downhole in oil and gas wells as well as surface facilities.
Berry, Sandra L. (Baker Hughes, a GE Company) | Palm, Dustin C. (Baker Hughes, a GE Company) | Usie, Marty J. (Baker Hughes, a GE Company) | Schutz, Ronald W. (TiCorr LLC) | Walker, Heath W. (Arconic Energy Systems)
Matrix acidizing treatments containing hydrogen fluoride (HF) acid have been utilized in stimulation treatments of offshore wells to remove skin associated with fines migration for many years. In the last few years, operators have moved toward the use of organic acid - HF acid treatments due to corrosion concerns in the downhole tubular strings during the initial pumping of live acid and in the Titanium Stress Joints (TSJ) during the acid flow back through the production riser. A corrosion inhibitor to inhibit any unspent HF in the acid flowback returns would be beneficial to operators. Production of spent acid flowing back through the production riser is seriously being considered because significant cost savings may be realized over other acid flowback options. However, although most HF acid systems are mostly and/or highly spent during the reaction time with the formation mineralogy, even small concentrations of remaining free HF in the spent acid returns can result in severe bore surface corrosion (etching) and byproduct hydrogen absorption by the riser system TSJ. Lab studies were performed with several different inhibitor formulations added to two different spent organic - HF acid fluid systems to determine the ability for these candidate inhibitors to thwart corrosion (etching) and corresponding hydrogen uptake on ASTM Grade 29 titanium (Ti-29) test coupons. These candidate inhibitors were subjected to four-hour exposure tests conducted at 170 F under 3500 psi pressure with various inhibitor concentrations to determine if the package could meet screening criteria of corrosion/etch rate of less than 0.5 mils per day (0.5 thousandths of an inch) and hydrogen uptake limits consistent with ASTM product specification limits for the short term exposure (i.e., four hours). These lab test results are compared to those from recent published lab test studies on titanium in live and spent HF containing acid fluids, along with discussion on practical implications and considerations for their field use. Developing a corrosion inhibitor to inhibit the residual HF acid in the spent flowback returns and prevent etching and hydrogen uptake by the TSJ in the production risers not only yields effective protection of the TSJ, allowing flowback fluids to be returned thru the production riser, but also offers a significant operational cost savings.