Results for “drilling” — Page 5

DOE OSTI2015

Impact of drilling fluid rheology and wellbore pressure on rock cuttings removal performance: numerical investigation

Drilling fluids exhibit non-Newtonian behavior which is generally described in the literature by two rheological models: Power Law and Herschel-Bulkley models. We have used Eulerian- Eulerian multiphase flow model to evaluate the drilling fluid flow patterns and filter cake formation patterns for both models for ultra-deep drilling conditions. Simulated drilling fluid flow patterns clearly show that the Herschel - Bulkley model exhibits fewer vortices around the drilling pipe, indicating better rock cuttings removal performance. In addition to mud rheology, we have analyzed the pressure drop variation with the filter cake formation on the wellbore during ultradeep drilling process. We have shown that filter cake thickness at the wall linearly increases with differential pressure between the well and formation. This implies that the differential pressure needs to be optimized. Very thin filter cake may lead to excessive fluid seepage into the permeable subterranean vertical zone resulting in a loss of fluid circulation and hence in a loss of rock cuttings removal. Yet, very thick filter cake reduces the effective diameter of the hole which may lead to a poor rock cuttings removal performance and stuck pipe. The mathematical model presented here needs to be experimentally validated when filter cake thickness data in deep drilling conditions become available. The model could be useful to provide drilling engineers insight on the filter cake formation, drilling fluid flow pattern, and give guide-line to optimize the filter cake as field experimental data are scarce.

02 PETROLEUM↗

DOE OSTI2015

SU-E-T-314: Dosimetric Effect of Smooth Drilling On Proton Compensators in Prostate Patients

Purpose: To evaluate the dosimetric effect of smooth drilling of proton compensators in proton prostate plans when compared to typical plunge drilling settings. Methods: Twelve prostate patients were planned in Eclipse treatment planning system using three different drill settings Smooth, Plunge drill A, and Plunge drill B. The differences between A and B were: spacing X[cm]: 0.4(A), 0.1(B), spacing Y[cm]: 0.35(A), 0.1(B), row offset [cm]: 0.2(A), 0(B). Planning parameters were kept consistent between the different plans, which utilized two opposed lateral beams arrangement. Mean differences absolute dosimetry in OAR constraints are presented. Results: The smooth drilled compensator based plans yielded equivalent target coverage to the plans generated with drill settings A and B. Overall, the smooth compensators reduced dose to the majority of organs at risk compared to settings A and B. Constraints were reduced for the following OAR: Rectal V75 by 2.12 and 2.48%, V70 by 2.45 and 2.91%, V65 by 2.85 and 3.37%, V50 by 2.3 and 5.1%, Bladder V65 by 4.49 and 3.67%, Penial Bulb mean by 3.7 and 4.2Gy, and the maximum plan dose 5.3 and 7.4Gy for option A vs smooth and option B vs smooth respectively. The femoral head constraint (V50<5%) was met by all plans, but it was not consistently lower for the smooth drilling plan. Conclusion: Smooth drilled compensators provide equivalent target coverage and overall slightly cooler plans to the majority of organs at risk; it also minimizes the potential dosimetric impacts caused by patient positioning uncertainty.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2018

High Temperature 300°C Measurement While Drilling System

Many countries around the world, including the USA, have untapped geothermal energy potential. Enhanced Geothermal Systems (EGS) technology is needed to economically utilize this resource. Temperatures in some EGS reservoirs can exceed 300°C. To effectively utilize EGS resources, an array of injection and production wells must be accurately placed in the formation fracture network. Therefore, EGS can greatly benefit from a high temperature directional drilling system. Most commercial services for directional drilling systems are rated for 175°C while geothermal wells require operation at much higher temperatures. Two U.S. Department of Energy (DOE) Geothermal Technologies Office (GTO) projects have been initiated to develop a 300°C capable directional drilling system, the first developing a drill bit, directional motor, and drilling fluid (award number DE-EE0002782), and the second adding navigation and telemetry systems. This report is for the second project, “High Temperature 300°C Measurement While Drilling System”, award number DE-EE0005505. The “High Temperature 300°C Measurement While Drilling (MWD)” system complements the already developed drilling system with real time navigation capability. It is comprised of 175°C directional measurement electronics including the required sensors for measuring inclination and azimuth in 3 axes. It is embedded in a cooling and temperature isolation system to protect the electronics and sensors from the higher temperature outside the system, which can reach 300°C. Building the cooling and isolation system from non-magnetic materials and keeping a required distance to any magnetic component, such as alternator parts, ensures a high quality measurement of the earth’s magnetic field. This is required to achieve the specified navigation accuracy. The MWD system has a turbine driven alternator that is capable of delivering the required electrical energy to the electronic system at a 300°C borehole temperature. Measured data will be communicated to the surface by mud-pulse-telemetry. For this purpose the tool has a mud-pulse-valve that is controlled by the measurement electronics to establish a serial data communication via the mud stream. The mud-pulse-valve is also built to operate under 300°C borehole conditions. Three prototypes of the 300°C MWD were built and tested. These systems are available for a joint application with the previously developed 300°C drilling system, in a geothermal well.

15 GEOTHERMAL ENERGY↗

DOE OSTI2024

Analysis of Rig Parameter Data Using Drilling Process Modeling Constraints, Volume 5: Utah FORGE Well 16B(78)-32

Drill rig parameter measurements are routinely used during deep well construction to monitor and guide drilling conditions for improved performance and reduced costs. While insightful into the drilling process, these measurements are of reduced value without a standard to aid in data evaluation and decision making. In the main body of this work (Volume 1), a method is demonstrated whereby rock reduction model constraints are used to interpret drilling response parameters; the method could be applied in real-time to improve decision-making in the field and to further discern technology performance during post-drilling evaluations. Drilling parameters are evaluated using laboratory-validated rock reduction models for predicting the phenomenological response of drag bits (Detournay and Defourny, 1992) in computational algorithms. The method presented has applicability to development of advanced analytics on future geothermal wells using real-time electronic data recording for improved performance and reduced drilling costs. A drilling cost model is also used to show the tradeoff between rate of penetration and bit life and the influence on interval drilling costs. Details of the bit specifications and performance are cataloged in an independent volume, documented under separate cover, for each of the four wells, and include Volume 2: Utah FORGE 16A(78)-32; Volume 3: Utah FORGE 56-32; Volume 4: Utah FORGE 78B-32 and Volume 5: Utah FORGE 16B(78)-32.

15 GEOTHERMAL ENERGY↗

DOE OSTI2024

Analysis of Rig Parameter Data Using Drilling Process Modeling Constraints, Volume 4: Utah FORGE Well 78B-32

Drill rig parameter measurements are routinely used during deep well construction to monitor and guide drilling conditions for improved performance and reduced costs. While insightful into the drilling process, these measurements are of reduced value without a standard to aid in data evaluation and decision making. In the main body of this work (Volume 1), a method is demonstrated whereby rock reduction model constraints are used to interpret drilling response parameters; the method could be applied in real-time to improve decision-making in the field and to further discern technology performance during post-drilling evaluations. Drilling parameters are evaluated using laboratory-validated rock reduction models for predicting the phenomenological response of drag bits (Detournay and Defourny, 1992) in computational algorithms. The method presented has applicability to development of advanced analytics on future geothermal wells using real-time electronic data recording for improved performance and reduced drilling costs. A drilling cost model is also used to show the tradeoff between rate of penetration and bit life and the influence on interval drilling costs. Details of the bit specifications and performance are cataloged in an independent volume, documented under separate cover, for each of the four wells, and include Volume 2: Utah FORGE 16A(78)-32; Volume 3: Utah FORGE 56-32; Volume 4: Utah FORGE 78B-32 and Volume 5: Utah FORGE 16B(78)-32.

15 GEOTHERMAL ENERGY↗

DOE OSTI2024

Analysis of Rig Parameter Data Using Drilling Process Modeling Constraints, Volume 3: Utah FORGE Well 56-32

Drill rig parameter measurements are routinely used during deep well construction to monitor and guide drilling conditions for improved performance and reduced costs. While insightful into the drilling process, these measurements are of reduced value without a standard to aid in data evaluation and decision making. In the main body of this work (Volume 1), a method is demonstrated whereby rock reduction model constraints are used to interpret drilling response parameters; the method could be applied in real-time to improve decision-making in the field and to further discern technology performance during post-drilling evaluations. Drilling parameters are evaluated using laboratory-validated rock reduction models for predicting the phenomenological response of drag bits (Detournay and Defourny, 1992) in computational algorithms. The method presented has applicability to development of advanced analytics on future geothermal wells using real-time electronic data recording for improved performance and reduced drilling costs. A drilling cost model is also used to show the tradeoff between rate of penetration and bit life and the influence on interval drilling costs. Details of the bit specifications and performance are cataloged in an independent volume, documented under separate cover, for each of the four wells, and include Volume 2: Utah FORGE 16A(78)-32; Volume 3: Utah FORGE 56-32; Volume 4: Utah FORGE 78B-32 and Volume 5: Utah FORGE 16B(78)-32.

15 GEOTHERMAL ENERGY↗

DOE OSTI2024

Analysis of Rig Parameter Data Using Drilling Process Modeling Constraints, Volume 1: Summary of Utah FORGE Wells 16A(78)-32, 56-32, 78B-32 and 16B(78)-32

Drill rig parameter measurements are routinely used during deep well construction to monitor and guide drilling conditions for improved performance and reduced costs. While insightful into the drilling process, these measurements are of reduced value without a standard to aid in data evaluation and decision making. In the main body of this work (Volume 1), a method is demonstrated whereby rock reduction model constraints are used to interpret drilling response parameters; the method could be applied in real-time to improve decision-making in the field and to further discern technology performance during post-drilling evaluations. Drilling parameters are evaluated using laboratory-validated rock reduction models for predicting the phenomenological response of drag bits (Detournay and Defourny, 1992) in computational algorithms. The method presented has applicability to development of advanced analytics on future geothermal wells using real-time electronic data recording for improved performance and reduced drilling costs. A drilling cost model is also used to show the tradeoff between rate of penetration and bit life and the influence on interval drilling costs. Details of the bit specifications and performance are cataloged in an independent volume, documented under separate cover, for each of the four wells, and include Volume 2: Utah FORGE 16A(78)-32; Volume 3: Utah FORGE 56-32; Volume 4: Utah FORGE 78B-32 and Volume 5: Utah FORGE 16B(78)-32.

15 GEOTHERMAL ENERGY↗

DOE OSTI2025

lllinois Storage Corridor CarbonSAFE Phase III: Pre-drilling Site Assessment: Prairie State Generating Company

The Illinois Storage Corridor project will drill a stratigraphic test well as part of the Illinois Storage Corridor CarbonSAFE Phase 3 project near the Prairie State Generating Company coal-fired power plant near Marissa, Illinois. The pre-drilling site evaluation has considered the primary target reservoirs, the Potosi Dolomite and St. Peter Sandstone, and primary seal, the Maquoketa Group. Data to be collected from the well include core, fluid samples, in situ well tests, geophysical logs intended to provide information on lithologic, geomechanical, and geophysical characteristics to determine the feasibility for the geologic sequestration of 50 million metric tons or more of injected carbon dioxide. The planned drilling site has been evaluated using available subsurface geologic data and analyses from the Illinois Basin. These data provide lithologic and structural information, shallow groundwater resource distribution, location of known nearby wellbores, and regional drilling characteristics. The data were used to generate geologic structure and isopach maps for the target reservoir and caprock strata and for prognosing the tops of major lithologic units to aid drilling and coring procedures. The regional analyses indicate that no known structural features are expected to negatively impact the target storage reservoir or caprock. No protected and sensitive areas, groundwater resources, or existing resource development are expected to be impacted by the proposed well drilling activities. The well is planned to be drilled to a total depth of approximately 5,600 feet (1,707 m) and terminate in the Precambrian. Cores (up to 5 intervals) will be collected from the Maquoketa Group, confining units above the St. Peter Sandstone, St. Peter Sandstone, confining units of the Potosi Dolomite and the Potosi Dolomite. Water samples will be attempted to be collected from the St. Peter Sandstone and Potosi Dolomite. Potential impact on drilling progress is a lost circulation zone in the Potosi Dolomite, which has been demonstrated to have intermittent cavernous porosity from karstification elsewhere in the Illinois Basin. This document also presents a preliminary coring and sampling program, proposed logging suite, and well testing program, all of which will be reviewed during drilling.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2018

Super Hot EGS and the Newberry Deep Drilling Project

A productive geothermal well drilled into super-hot rock (SHR) with a temperature above 400°C will produce super-critical fluid. At a flow rate of 60 kg/s, a SHR well could produce 50 MWe compared to 5-7 MWe for the same flow at 200°C. Even though these deeper, super-hot wells will cost more, the high energy density means power produced by engineered geothermal systems (EGS) can meet the market ($46 MW-hr) by directly tapping the heat source. We propose a proof of concept where hot rock is close to the surface (~5 km), and the cost of drilling and EGS stimulation will be lowest. A suitable, ready-to-go SHR site is on Newberry Volcano, Oregon, one of the largest geothermal heat reservoirs in the USA, extensively studied for the last 40 years. Millions of dollars have already been invested in the site by private geothermal developers and the US Department of Energy (DOE), resulting in a ready-to-use facility with the necessary infrastructure, environmental permits, land commitments, and monitoring plans. The Newberry Deep Drilling Project (NDDP) will be located at an idle geothermal exploration well, NWG 46-16, drilled in 2008, 3500 m deep and 320°C at bottom, which will be deepened another 1000 to 1300 m to reach 500 °C. The original well was drilled with few lost circulation zones and the temperature profile indicates conductive heat flow. Compared to other SHR projects world-wide, this well would return more materials (cuttings, core and fluids) with more predictable drilling conditions, thus providing a suite of data near and across the brittle-ductile transition in silicarich rocks. After drilling, a hydraulic well stimulation will both change the pore pressure in fractures and cool the fracture walls resulting in permeability enhancement through both thermal fracturing, and hydro-shearing. The first step for the NDDP was an International Continental Drilling Program (ICDP) sponsored workshop held at the OSU-Cascades campus in Bend from Sept. 10-14, 2017. The workshop concluded by setting ambitious goals for NDDP: 1) test EGS above the critical point of water, 2) collect samples of rocks within the brittle-ductile transition, 3) investigate volcanic hazards, 4) study magmatic geomechanics, 5) calibrate geophysical imaging techniques, and 6) test technology for drilling, well completion, and geophysical monitoring in a very high temperature environment. The second step, completed January 15, 2018, was submitting a proposal to ICDP for 46-16 deepening. The next steps will be to continue building a team with project, technology, and investment partners to make NDDP a reality.

EGS, Geothermal, Newberry↗

DOE OSTI2019

Wabash CarbonSAFE Subtask 7.1 – Pre-drilling Site Assessment Topical Report: DOE-FE0031626-1

The Wabash CarbonSAFE project will drill a stratigraphic test well at the Wabash Valley Resources facility near Terre Haute, Indiana. Lithologic, geomechanical, and geophysical data collected from samples testing and an extensive geophysical logging suite will be used to determine the feasibility for the geologic sequestration of 50 million metric tons or more of injected carbon dioxide. The primary target reservoir and caprock to be investigated for the Wabash CarbonSAFE project are the Mt. Simon Sandstone and Eau Claire Shale, respectively. The project team has assessed the planned Wabash #1 drilling site using subsurface geologic data and analyses from both Illinois and Indiana. These data were used to generate geologic structure and isopach thickness maps for target reservoir and caprock layers which were incorporated into a detailed discussion of the nature of the Illinois Basin’s Cambro-Ordovician carbon dioxide storage complex at the drilling site. Formation tops were prognosed for 19 lithologic units to aid drilling and coring procedures. Additional GIS analysis indicates that no known structural features will negatively impact the target storage reservoir or caprock, nor will protected and sensitive areas, groundwater resources, or existing resource development be negatively affected by Wabash #1 drilling activities. The Wabash #1 Geologic/Structure Test well drilling permit was awarded by Indiana Department of Natural Resources (IN-DNR) – Division of Oil and Gas on November 12th, 2019, and the well is expected to be drilled to a total depth of approximately 8,350 feet. Potential impacts on drilling progress include abandoned underground coal mines which mined the Springfield and Survant coals until 1964 and 1954, respectively, and a lost circulation zone in the Potosi Dolomite, which has been demonstrated to have intermittent cavernous porosity from karstification. This document also details the coring and sampling program, proposed logging suite, and well testing program, all of which will be dynamically reviewed as drilling progresses.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2016

Directional Drilling Technology for HLW Disposal - Outline of System and its Application - 16078

During high-level waste (HLW) disposal site selection, borehole measurement and logging to investigate the hydro-geological and geo-mechanical conditions of the host rocks is a very important way to examine the potential of the disposal candidates. In Japan, attention is being given to Neogene soft sedimentary rock as the host rock for HLW disposal. In particular, the soft sedimentary rock in coastal areas is thought to be one of the best candidates, because there is little driving force from underground water. Directional drilling is supposed to be efficient under limited topographic and geological conditions, and the Central Research Institute of Electric Power Industry (CRIEPI) has been conducting a project on directional drilling and logging/measurement technologies since 2000. Basic directional drilling system was developed and the system was applied to the Neogene normal sedimentary rock at the Hokushin area of the Horonobe town in Hokkaido. The borehole was drilled to the 700 m long and the applicability of the system was confirmed until 2004. A basic directional drilling system was developed, and the system was applied to the Neogene normal sedimentary rock in the Hokushin area, in the town of Horonobe in Hokkaido. A 700-m borehole was drilled, and the applicability of the system was confirmed in 2004. After conducting a seismic reflection survey for the Omagari fault distribution at the Kami-Horonobe area in the town of Horonobe, a drilling site was selected, and a borehole trace was planned to perpendicularly intersect the fault zone in 2005. Considering the planned trace, a 1000-m-long borehole was drilled to a depth of 450 m. From 750 m to the bottom (1000 m), the borehole was horizontal. The total core recovery was 99.8%, even though it was drilled in the fault zone. The geological, hydrological, geo-mechanical, geophysical, and geochemical data were collected using borehole logging/measurement/survey and core logging/measurement/analysis, and the Omagari fault was characterized. After conducting all the work in the borehole, a steel pipe was inserted into the borehole to case the wall. Open hole sections for monitoring were constructed considering the hydro-geological conditions throughout the hole. Then, the monitoring system was inserted and set up to obtain the initial conditions of the groundwater pressure and chemistry. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2019

Sulfide Stress Corrosion Cracking Behavior of G105 and S135 High-Strength Drill Pipe Steels in H{sub 2}S Environment

Slow strain rate testing was employed to investigate the sulfide stress corrosion cracking (SSCC) behavior of low-carbon high-strength drill pipe steels (G105 and S135) in the simulated drilling environment containing H{sub 2}S. Results reveal that both G105 and S135 steels have a high SSCC susceptibility in the simulated drilling environment containing H{sub 2}S. In the range of experimental slow strain rate, the SSCC sensitivity of drill pipe steel increases with the decrease in slow strain rate, and the ductility and fracture properties of drill pipe steels also decrease obviously. With the increase in the steel strength, the SSCC sensitivity of the drill pipe steel increases, and the S135 drill pipe steel has higher SSCC sensitivity than G105. There is no obvious plastic deformation on the fracture surface of G105 and S135 steels in H{sub 2}S solution. The cracks of fracture sprout on the surface of the specimen, the instantaneous fracture zone is in the middle, and the fracture can be divided into the cracking and the final fracture zone. The SSCC mechanisms of two drill pipe steels are hydrogen embrittlement. The hydrogen enters the steel and reduces the binding force of the iron atom, resulting in cleavage fracture.

36 MATERIALS SCIENCE↗

DOE OSTI2019

Geothermal Drilling and Completions: Petroleum Practices Technology Transfer

In the summer of 2013, members of the National Renewable Energy Laboratory (NREL) and Colorado School of Mines (CSM) identified an opportunity to improve geothermal drilling operations by transferring practices from the petroleum drilling field. The NREL/CSM group noted that significant changes in drilling efficiencies in petroleum operations have been made during the last decade. For example, five years ago, 14,000-foot wells in Wyoming took 60 days to drill. However, in September of 2015, these same wells were drilled in 7 days. This significant decrease in required drilling days resulted from analysis, goal setting, and management and technology improvements. The geothermal drilling industry can import these methods and technologies, where appropriate, with the possibility of similar improvements in drilling operations.

15 GEOTHERMAL ENERGY↗

NASA NTRS2012

Single Piezo-Actuator Rotary-Hammering (SPaRH) Drill

The search for present or past life in the Universe is one of the most important objectives of NASA's exploration missions. Drills for subsurface sampling of rocks, ice and permafrost are an essential tool for astrobiology studies on other planets. Increasingly, it is recognized that drilling via a combination of rotation and hammering offers an efficient and effective rapid penetration mechanism. The rotation provides an intrinsic method for removal of cuttings from the borehole while the impact and shear forces aids in the fracturing of the penetrated medium. Conventional drills that use a single actuator are based on a complex mechanism with many parts and their use in future mission involves greater risk of failure and/or may require lubrication that can introduce contamination. In this paper, a compact drill is reported that uses a single piezoelectric actuator to produce hammering and rotation of the bit. A horn with asymmetric grooves was design to impart a longitudinal (hammering) and transverse force (rotation) to a keyed free mass. The drill requires low axial pre-load since the hammering-impacts fracture the rock under the bit kerf and rotate the bit to remove the powdered cuttings while augmenting the rock fracture via shear forces. The vibrations 'fluidize' the powdered cuttings inside the flutes reducing the friction with the auger surface. This action reduces the consumed power and heating of the drilled medium helping to preserve the pristine content of the acquired samples. The drill consists of an actuator that simultaneously impacts and rotates the bit by applying force and torque via a single piezoelectric stack actuator without the need for a gearbox or lever mechanism. This can reduce the development/fabrication cost and complexity. In this paper, the drill mechanism will be described and the test results will be reported and discussed.

ultrasonic impacts↗

NASA NTRS2013

Wireline Deep Drill for the Exploration of Icy Bodies

One of the most pressing current questions in space science is whether life has ever arisen anywhere else in the universe. Water is a critical prerequisite for all life-as-we-know-it, thus the possible exploration targets for extraterrestrial life are bodies that have or had copious liquid: Mars, Europa, and Enceladus. Due to the oxidizing nature of Mars' surface, as well as subsurface liquid water reservoirs present on Europa and Enceladus, the search for evidence of existing life must likely focus on subsurface locations, at depths sufficient to support liquid water or retain biologic signatures. To address these questions, an Auto-Gopher sampler has been developed that is a wireline type drill. This drill is suspended on a tether and its motors and mechanisms are built into a tube that ends with a coring bit. The tether provides the mechanical connection to a rover/lander on a surface as well as power and data communication. Upon penetrating to a target depth, the drill is retracted from the borehole, the core is deposited into a sample transfer system, and the drill is lowered back into the hole. Wireline operation sidesteps one of the major drawbacks of traditional continuous drill string systems by obviating the need for multiple drill sections, which add significantly to the mass and the complexity of the system (i.e. penetration rate was 40 cm per hour). Drilling to 2 meter depth and recovering of cores every 10 cm took a total time of 15 hours (a single step of drilling 10 cm and retrieving the core was 45 minutes). Total energy to reach the 2 m depth was 500 Whr. The Weight on Bit was limited to less than 70 Newton. The core recovery was 100%.

sampling↗

DOE OSTI2019

Natural Gas Drilling near the Underground Nuclear Test Site of Rulison, Colorado - 19571

In 1969, the Project Rulison test was conducted in western Colorado using a nuclear device to stimulate natural gas production by fracturing low-permeability, gas-bearing rock. The presence of radionuclides (specifically tritium) in the produced gas persisted above acceptable levels, and the test was abandoned. Advances in hydrofracturing technology over the past 10-15 years have revolutionized the extraction of hydrocarbons from low-permeability formations, leading to a significant increase of drilling in the Rulison area. Drilling activity nearing the Rulison site has raised concerns that remnant radioactivity might be encountered. The site, now under the care of the US Department of Energy (DOE), is protected by a 16-hectare (40 acre) institutional control boundary (Lot 11) that prohibits drilling or extraction of materials below 1830 meters (6000 feet) within the lot boundary. Drilling within 0.8 kilometer (0.5 mile) of the site requires a hearing before the Colorado Oil and Gas Conservation Commission. DOE recommends that gas developers adopt a conservative, staged drilling approach, allowing gas reserves near the Rulison site to be recovered in a manner that minimizes the likelihood of encountering contamination. The staged approach calls for collecting data from wells away from the site before drilling closer. For instance, the wells 1.2 kilometer (0.75 mile) west of the site did not encounter any unexpected geologic conditions and now have 8 years of production without encountering any detonation-related radionuclides. The next set of wells would be 0.8 kilometer (0.5 mile) west of the site. This sequential method drills first at locations with a low probability of encountering contamination and then moves closer. This process protects public safety while allowing the collection of additional data to confirm that contamination has not migrated beyond the 16-hectare (40-acre) institutional control boundary. The staged drilling approach was simulated with a modeling effort that estimates the current extent of contamination and the potential for production-induced contaminant migration to nearby wells. The model incorporates geologic data from nearby wells and was calibrated to production data from both the reentry well production testing (1970-1971) and the wells 1.2 kilometer (0.75 mile) from the site that began producing in 2010. The geologic data include both sand/shale distribution statistics as well as the tendency of hydrofractures to preferentially propagate east and west due to the regional stress field. The model results indicate that it is unlikely that wells near the site would ever encounter site-related radionuclides. (authors)

03 NATURAL GAS↗

DOE OSTI2014

Development of a Mine Rescue Drilling System (MRDS)

Sandia National Laboratories (Sandia) has a long history in developing compact, mobile, very high-speed drilling systems and this technology could be applied to increasing the rate at which boreholes are drilled during a mine accident response. The present study reviews current technical approaches, primarily based on technology developed under other programs, analyzes mine rescue specific requirements to develop a conceptual mine rescue drilling approach, and finally, proposes development of a phased mine rescue drilling system (MRDS) that accomplishes (1) development of rapid drilling MRDS equipment; (2) structuring improved web communication through the Mine Safety & Health Administration (MSHA) web site; (3) development of an improved protocol for employment of existing drilling technology in emergencies; (4) deployment of advanced technologies to complement mine rescue drilling operations during emergency events; and (5) preliminary discussion of potential future technology development of specialized MRDS equipment. This phased approach allows for rapid fielding of a basic system for improved rescue drilling, with the ability to improve the system over time at a reasonable cost.

42 ENGINEERING↗

DOE OSTI2015

Energy Storage and Generation for Extreme Temperature and Pressure and Directional Measurement While Drilling Applications

FastCAP Systems Corporation has successfully completed all milestones defined by the award DE-EE0005503. Under this program, FastCAP developed three critical subassemblies to TRL3 demonstrating proof of concept of a geothermal MWD power source. This power source includes an energy harvester, electronics and a novel high temperature ultracapacitor (“ultracap”) rechargeable energy storage device suitable for geothermal exploration applications. FastCAP’s ruggedized ultracapacitor (ultracap) technology has been proven and commercialized in oil and gas exploration operating to rated temperatures of 150°C. Characteristics of this technology are that it is rechargeable and relatively high power. This technology was the basis for the advancements in rechargeable energy storage under this project. The ultracap performs reliably at 250°C and beyond and operates over a wide operating temperature range: -5°C to 250°C. The ultracap has significantly higher power density than lithium thionyl chloride batteries, a non-rechargeable incumbent used in oil and gas drilling today. Several hermetically sealed, prototype devices were tested in our laboratories at constant temperatures of 250°C showing no significant degradation over 2000 hours of operation. Other prototypes were tested at Sandia National Lab in the month of April, 2015 for a third party performance validation. These devices showed outstanding performance over 1000 hours of operation at three rated temperatures, 200°C, 225°C and 250°C, with negligible capacitance degradation and minimal equivalent series resistance (ESR) increase. Similarly, FastCAP’s ruggedized electronics have been proven and commercialized in oil and gas exploration operating to rated temperatures of 150°C. This technology was the basis for the advancements in downhole electronics under this project. Principal contributions here focused on design for manufacture innovations that have reduced the prototype build cycle time by a factor of 10x. The electronics have demonstrated a substantially reduced design cycle time by way of process and material selection innovations and have been qualified for 250°C / 10 Grms for at least 200 hours. FastCAP has also invented a rotary inertial energy generator (RIEG) to harvest various mechanical energy sources that exist downhole. This device is flow-independent and has been demonstrated as a proof of concept to survive geothermal well temperatures under this project. The herein energy harvester has been developed to provide operational power by harvesting rotational mechanical energy that exists downhole in geothermal drilling. The energy harvester has been tested at 250°C / 10 Grms for 200 hours. Deployment of these technologies in geothermal drilling and exploration applications could have an immediate and significant impact on the effectiveness and efficiency of drilling processes, particularly with regard to use of advanced logging and monitoring techniques. The ultimate goal of this work is to reduce drilling risk to make geothermal energy more attractive and viable to the customer. Generally speaking, we aim to support the transfer of MWD techniques from oil and gas to geothermal exploration with considerations toward the practical differences between the two. One of the most significant obstacles to the deployment of advanced drilling and production techniques in the geothermal context are limitations related to the maximum operating temperatures of downhole batteries used to provide power for downhole sensors, steering tools, telemetry equipment and other MWD/LWD technologies. FastCAP’s higher temperature ultracapacitor technology will provide power solutions for similar advanced drilling and production techniques, even in the harsher environments associated with geothermal energy production. This ultracapacitor will enable downhole power solutions for the geothermal industry capable of the same reliable and safe operation our team has demonstrated in the oil and gas context. Without batteries, geothermal MWD is left without a downhole power source. Some very high temperature turbines exist but provide unsteady, intermittent power and no power when the flow is off. In high loss formations common to geothermal exploration, it will be auspicious to support air drilling in which case there is no flow to power a turbine at all. In the best case, rechargeable energy storage will help to buffer unsteady power from non-battery power sources and in the worst case it will be needed to store energy from highly intermittent sources to provide a continuously operable power source to the tool.

15 GEOTHERMAL ENERGY↗