Abstract The paper focuses on the use of dissolvable plugs in plug and perf completions, which allows the frac operations to be carried out, isolating between stages, and when the job is complete, the well can be flowed-back immediately. The need to mill out as with conventional plug is eliminated as each plug is disintegrated to a fine powder, not generating any flow restriction. Risks associated with milling and potential casing damage is eliminated, resulting in safer operations and operational savings. It also reduces the possibility of filling the open fractures with debris or chips from the milling process, minimizing damage to the fracture permeability. The focus of this paper will be on the dissolvable plug used to isolate the stages, which holds pressure for enough amount of time accordingly to the well operations. The design of these plugs also allows them to be used in long horizontal or extended reach wells without concern regarding the mechanical limitations of the coiled tubing during milling phase. The plug performance supports increasing the number of stages in these wells which resulting in higher well productivity while minimizing the well integrity aspect as the milling operation is not required.

Abstract The objective of this paper is to demonstrate that the combination of selective completions with wide-range ESPs using Y-tools can be successfully deployed and operated. This represents a major impact in operating cost by minimizing future major workover interventions for Water Shut-off (WSO) and/or zonal changes. The team analyzed different completion concepts (e.g., dual completions, multi-zone with ICDs/ICVs, etc), conducted a screening & ranking analysis and concluded that the conventional selective completion combined with a tubing conveyed wide-range ESP was the top ranked option which would represent the best cost/benefit among all the other options. Selective completion with flow control equipment operated by slickline tools (unlike Intelligent Down Hole Flow Control) is fit-for-purpose completion type for a large onshore oil field such as the Greater Burgan, with multiple zone reservoirs. In selective completions, reservoir parameters such as well productivity index and bottom-hole pressure could change throughout the life of the well which shall be taken into consideration during ESP design. Multiple simulations were conducted to determine the best ESP design to cover optimal-case and worst-case scenarios at opened and closed zones. Each scenario was presented with a different productivity index and bottom-hole pressure with corresponding flowrate, motor load, and motor temperature. In which, the ESP design ensured continuous flow to the surface, minimum or no gas presence at the pump intake, and sufficient flowrate for motor cooling, within acceptable motor load ranges and pump operating ranges. It has been shown with the results that following comprehensive ESP design modeling in selectively completed wells can potentially yield a resilient wide-range ESP system that can withstand dynamic reservoir conditions. In KOC and in any brown field, the utilization of wide-range ESPs in combination with selective completions will reduce operational cost and deferred production, allow effective and un-expensive rig-less WSO via slickline operations, conduct well surveillance and flow performance adjustment, maximize well bore utilization and reduce requirement of workover rigs.

Titanium dioxide is often designed as an excellent catalyst carrier and photocatalyst due to its tunable structure. In this paper, iron-doped ordered mesoporous titanium dioxide was prepared. These powders were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and nitrogen physisorption (BET). It was found that mesoporous titanium dioxide powders containing 1% Fe doping were roasted at 350 °C to favor the formation of ordered mesoporous titanium dioxide. This is due to the fact that Fe doping can enhance the pore structure and improve the orderliness of pores, while the increase in temperature can accelerate the growth of grains.

Abstract Plug and perf technique is a common method to unlock the potential of tight gas formations. The conventional method is to set millable plugs to establish zonal isolation between target stages. A new degradable frac plug has been introduced for high pressure and high temperature applications in sandstone formations plug and perf hydraulic fracturing operations. The development and deployment of the degradable frac plugs that are capable of holding 32 hours of targeted pressure to optimize the cost and time of the conventional well intervention in tight gas reservoirs in Saudi Arabia is presented in this paper. In conventional plug and perf stimulation operations each plug is milled out via coiled tubing. This process increases operational risk and cost associated with multiple downhole trips. Another challenge is wellbore accessibility post stimulation operations. Without changing the fracturing design, two degradable plugs in a three-stage well were deployed. Downhole conditions presented significant challenges including high temperatures of 285 F and pressures. By using a degradable plug, post-frac interventions can be eliminated as the entire plug will degrade in downhole conditions. This would allow the well to be brought online faster than a conventional method would allow. Operational challenges have been experienced during the first deployment of the plug. The plug has successfully held pressure for 32 hours while being exposed to wellbore fluids, which is one of the longest times achieved for a degradable frac plug. One of the main reasons of such success is that the plug is composed of high-grade material. While the plug maintained its integrity for 32 hours in high pressure, it degraded to fine particles post frac operations. Furthermore, the plug was trial tested without affecting the stimulation goals or the overall operation for such well. On this trial test, the plug has shown the ability to eliminate HPCT trips and the associated risks of HPCT intervention. To confirm dissolution of the plugs, an assessment CT run was performed and confirmed shallower plug was not dissolved after 32 hours while the deeper plug already dissolved. With the spread of plug and perf technology on a global level and the increase of horizontal multistage stimulation methods, it is important to capitalize on fit for purpose technologies versus a one-size fits all approach. To address the challenges associated with longer laterals and increasing stage counts, degradable plug technology can be used to improve well economics and reduce associated risks. The elimination of mechanical intervention is the next breakthrough in efficiency gains to increase laterals and achieve higher stage counts.

IntroductionMentor Mothers (MM) provide peer support to pregnant and postpartum women living with HIV (PPWH) and their infants with perinatal HIV exposure (IPE) throughout the cascade of prevention of vertical transmission (PVT) services. MM were implemented in Zambézia Province, Mozambique starting in August 2017. This evaluation aimed to determine the effect of MM on PVT outcomes.MethodsA retrospective interrupted time series analysis was done using routinely collected aggregate data from 85 public health facilities providing HIV services in nine districts of Zambézia. All PPWH (and their IPE) who initiated antiretroviral therapy (ART) from August 2016 through April 2019 were included. Outcomes included the proportion per month per district of: PPWH retained in care 12 months after ART initiation, PPWH with viral suppression and IPE with HIV DNA PCR test positivity by 9 months of age. The effect of MM on outcomes was assessed using logistic regression.ResultsThe odds of 12‐month retention increased 1.5% per month in the pre‐MM period, compared to a monthly increase of 7.6% with‐MM (35–61% pre‐MM, 56–72% with‐MM; p < 0.001). The odds of being virally suppressed decreased by 0.9% per month in the pre‐MM period, compared to a monthly increase of 3.9% with‐MM (49–85% pre‐MM, 59–80% with‐MM; p < 0.001). The odds of DNA PCR positivity by 9 months of age decreased 8.9% per month in the pre‐MM period, compared to a monthly decrease of 0.4% with‐MM (0–14% pre‐MM, 4–10% with‐MM; p < 0.001). The odds of DNA PCR uptake (the proportion of IPE who received DNA PCR testing) by 9 months of age were significantly higher in the with‐MM period compared to the pre‐MM period (48–100% pre‐MM, 87–100% with‐MM; p < 0.001).ConclusionsMM services were associated with improved retention in PVT services and higher viral suppression rates among PPWH. While there was ongoing but diminishing improvement in DNA PCR positivity rates among IPE following MM implementation, this might be explained by increased uptake of HIV testing among high‐risk IPE who were previously not getting tested. Additional efforts are needed to further optimize PVT outcomes, and MM should be one part of a comprehensive strategy to address this critical need.

Abstract A major North Sea operator was looking to improve production from low permeable reservoirs in mature assets. Under-displaced, high proppant concentration fracs must be pumped in an efficient manner to unlock the value potential. A new single-trip, multistage stage proppant fracturing system was developed to tackle these operational constraints and reliably perform in challenging offshore environments. This paper presents the evolution of this system from a concept to field implementation on the Norwegian Continental Shelf. The developed solution, a frac sleeve (FS) system operated by a service tool assembly (STA) which can be run on drillpipe or coiled tubing. The unique feature of this system is that it allows multistage stimulation in a single trip without utilizing slips or packers, which could pose the risk of a stuck STA. Suited for both open-hole and cemented applications, the system is particularly beneficial for wells with limited slack-off capabilities. Key considerations of the design included operability in proppant-packed environments, erosion resistance, and multiple contingencies built into the STA to allow operational flexibility. An extensive qualification program was successfully executed to validate the system's functionality, particularly in hostile, proppant-packed environments, including an erosion test wherein 2,000 tons of proppant was pumped through the STA at 30 bbl/min. In preparation for field deployment, drillpipe and liner simulations were run, and operational planning and risk assessments were held. Following these assessments, the system was deployed for the North Sea operator in a trial well in summer 2021. During the stimulation program, an under-displaced, high rate, and high proppant concentration frac was pumped in each stage, followed by immediate closing of the sleeves prior to reversing out the remaining under displaced proppant. This paper captures the wins, challenges, and key learnings from the initial trial well, and how these learnings were used to optimize the second well. Also detailed is the lifecycle of a novel, patented proppant-stimulation technology starting from initial concept to downhole deployment. Enabling optimized, proppant fracturing in an operationally efficient manner plays a crucial role in improving the productivity and economic viability of a well, and allows for improved oil recovery (IOR) from existing offshore infrastructure. The findings and lessons learned in this paper will contribute to the state of knowledge regarding proppant fracturing on the Norwegian Continental Shelf.

Abstract The liner shoe is a critical component of the lower completion architecture, allowing for auto-filling of the liner and enabling circulation during deployment, followed by closure to provide a closed system. Advancements in completion technologies have resulted in the development of an intelligent electronic liner shoe (ELS) that can be remotely operated without the need for intervention or pumping trigger devices downhole. The electronic liner shoe suited for deployment on 4½-in. liner was developed based on specific requirements from a major operator in the middle east. The electronic liner shoe was qualified per ISO 14998/API 19AC requirements up to 280°F. Additionally, the electronics module incorporated in the tool was vibration and shock tested at temperature. After an extensive qualification test program and thorough pre-job qualification and planning, candidate wells were chosen for the initial deployment of the ELS in Onshore wells. The ELS was first deployed in November 2020 in the Bab field in UAE. This paper highlights the excellent deployment performance using ELS for the onshore field development in UAE. This paper also presents the operational considerations for programming the remote activation mechanism, pre-job risk analysis, technology qualification, and post-job lessons from the first installation, resulting in the ELS’ successful deployment in six additional wells in the onshore fields. The paper also shares the unique benefits the ELS provided the operator towards enhancing operational efficiency, as well as reducing risk and costs associated with running liners.

Abstract A toe initiation sleeve is a tool installed in the toe of a completion liner and is used to establish a flowpath to the reservoir without the use of intervention. Conventional toe initiation sleeves require either intervention or increasing pressure to higher than the liner test pressure to activate. These methods have inherent cost and operational risks. This paper will present the development, qualification, and deployment of a multicycle, time-delay cementable toe initiation sleeve that allows for interventionless activation without exceeding the liner test pressure. This development greatly improves operational efficiency and eliminates risk associated with conventional toe initiation sleeves. A major operator in the North Sea required an ISO V0 rated toe initiation sleeve to be developed and qualified. Design criteria for the tool was identified, and the design was developed based on field-qualified seal technology. Individual component and full-scale validation testing was performed to complete the product qualification, followed by field trials in 2019. With its unique time-delay feature, the newly developed ATS (Advanced Toe Sleeve) allows for an unlimited number of pressure cycles to be performed while also keeping the well V0 barrier in place, and activates at below liner test pressure. This paper will discuss the technology development and implementation project, resulting in ISO 14998 V0-qualified cemented ATS being installed in nearly 40 wells in the same field. This paper will also provide insight into how the ATS provides unique benefits to the operator during various phases of the well's life. Cementing: One moving part and opening sleeve isolated from the inside diameter (ID) allow for pumping darts through the ATS without the risk of opening Setting liner/testing liner: Time-delay features allow for setting liner and testing the liner at higher pressures than ATS opening pressure. Well cleanup/displacing to lower density fluid: Time-delay function allows for opening the ATS at lower pressure than the well has seen during previous operations. Completion: ATS design and qualification grade reduce completion steps and costs for the operator. Stimulation: ATS eliminates the need for intervention, reducing the operational steps and costs for the operator. The advanced toe sleeve with built-in time-delay features maintains the liner integrity throughout the various well operations. The number of available pressure cycles can be predetermined, and the activation of the various cycles can be precisely controlled thereby also controlling when the tool is activated to achieve injectivity. This paper will present the development and field-wide implementation of the ATS technology, which has rapidly gained operator acceptance and resulted in significant time and cost savings.

Abstract The hydraulic fracture treatment (HFT) and its effectiveness to enhance wellbore drainage directly correlate with each well’s overall production performance and underlining economics. This paper will discuss the potential of ultra high stage count Single Point Entry (SPE) sleeves and their ability to increase control over proppant placement and isolation during the HFT as a method for optimizing well performance, economics, and reduce non-uniformity between treatments and wells. To address the limitations of current completion methods, full ID single point entry systems have been developed for open hole and cemented applications. These systems provide unlimited frac stage count with lower frac tortuosity, provide increased control over proppant placement and well production, reduce or eliminate over- flush and formation damage, and achieve higher efficiency during and after frac stimulation than previous conventional plug-and-perf (PnP) and sleeve systems, thereby reducing costs. While the ball-and-seat completion technique revolutionized the efficiency of multi-stage single point entry fracturing, its vast array of limitations (primarily ID restrictions), limited stage count, and compatibility with cemented liners quickly sidelined it in place of PnP. PnP offers increased surface area contact through additional entry points compared to sleeve systems of the past and remains the accepted method for achieving zonal isolation and initiation during stimulation. However, the time intensive operations of PnP present challenges in maintaining efficiencies due to variability in wireline during deployment and coiled tubing during millouts. The increase in number of clusters per stage and number of stages per well achieved with PnP often results in higher stimulated rock volumes (SRV) however, due to the number of multiple clusters open simultaneously, this method gained a "pump-n-pray" reputation due to the uncertainty of cluster efficiency and its unpredictability. The lack of cluster control over the years has created a series of challenges in terms of parent-child well relationships and spacing, economical asset development, and loss of potential production. With over 4,000 stages fracture stimulated across US, Canada, and Asia, some wells containing 220 individual stages, this paper will address the differences in production in terms of bbl of oil equivalent (BOE) for direct and indirect offsets in trials, compare capital efficiency with spud to put on production (POP) timelines, demonstrate economical completion optimization for lower commodity pricing of oil, and carbon intensity reduction measures to lower greenhouse gas emissions.

The prevalence of food insecurity among undergraduate students is higher than the national average and associated with adverse academic outcomes. Our objective was to describe the prevalence of food insecurity, food access behaviors, and associations between food security status and well-being in a dental student population. All dental students (N=328) enrolled in the College of Dentistry at the University of Iowa in the fall 2019 semester were invited to participate. The survey was designed to query demographic variables, food security status (i.e., the United States Department of Agriculture's 10-item Adult Food Security Module), and food- or hunger-related well-being (i.e., sleep, academic performance, and stress). The survey was administered using the Qualtrics survey platform. Following the initial invitation, students were sent two reminders and allowed 3 weeks for completion. The survey response rate was 24.7%. Forty-seven percent of respondents were food insecure. Food insecure students were more likely to attend collegiate programming (e.g., lunch and learns) for the primary purpose of obtaining free food than their food secure peers (p<0.001). In addition, food insecure students were more likely to report experiencing food- or hunger-related sleep (p=0.001), study or academic performance (p<0.001), or stress difficulties than their food secure peers (p<0.001). The prevalence of food insecurity in dental students was relatively high and associated with adverse food- and/or hunger-related well-being outcomes. Food insecurity might be a barrier to dental student success, compromising their immediate health and ability to learn.