scholarly journals Feasibility of repurposing existing and abandoned hydrocarbon wells in the form of a geothermal well-triplet system

2021 ◽  
Vol 11 (2) ◽  
pp. 2-8
Author(s):  
Dávid Bretán ◽  
Péter Szűcs ◽  
Rita Miklós ◽  
Csaba Ilyés

There are various types of extraction and utilization possibilities of geothermal energy, of which a large group is energy recovery. The development of this sector is slow mainly due to its high initial investment demand and the long planning phase. The overall goal of the present research is cutting the cost of the drilling phase as the most expensive part of the establishment by repurposing unused and abandoned hydrocarbon wells. The article assesses the feasibility of a geothermal well-triplet system chosen to be the most promising technique amongst several utilization possibilities depending on the characteristics of both the geological media and the method itself. From the 14 examined abandoned wells three were found to be suitable based on their current condition and distance from each other. The mentioned technique requires an adequately porous and permeable media which was not provided by the initial depth of the wells, thus the considerable option left was to overdrill the existing wells till they reach the target geology, the known fractured karstic aquifer below. The current study summarizes the final results of a long going research, from the geographical-, lithological surveys till the potential heat-transport modeling. This article supports the final aspirations of a further going research project as an integral part of it carried out by the University of Miskolc.

2021 ◽  
Vol 73 (01) ◽  
pp. 32-35
Author(s):  
Judy Feder

Geothermal energy has been described as an engineering problem that, when solved, provides the clean, reliable, safe, and affordable energy being sought globally. It is highly likely that the engineers who play the biggest role in solving that problem, and the technologies they adapt and advance, will come from oil and gas. There is enough energy in the earth’s crust, just a few miles down, to power all of humanity for ages, according to the US Advanced Research Projects Agency-Energy. The problem is how to tap into it safely, efficiently, and cost effectively. After many years of failure to launch because of technology or cost limitations, new companies and technologies - and smarter ways of leveraging those that already exist - are bringing geothermal out of its doldrums, to the point that it may finally be ready to scale and become a major player in the transition to cleaner energy, according to Jamie Beard, executive director of the Geothermal Entrepreneurship Organization (GEO) at The University of Texas at Austin (UT-Austin). “The cutting-edge technological developments in geothermal are devoted to drilling into ever-deeper, hotter, and harder rock,” she said, “and oil and gas holds the key to cost reduction for all of these concepts.” Eric Van Oort, drilling and well engineering expert, educator, and scientist, agrees. The UT-Austin engineering professor and director of the rig automation and performance improvement in drilling (RAPID) industry consortium, said, “Fifty to seventy-five percent of the cost of geothermal development is tied up in drilling and well construction. To scale it, we have to reduce that cost.” Designing for Extremes Well design for geothermal wells is similar to that for oil and gas wells. The challenges arise from drilling deeper and deeper, into hotter and hotter rock. Heat ranging from 150°C (302°F) to 373°C (703°F) and above can be used to profitably generate electricity. Oil and gas well designs traditionally have not had to contend with these extremes. Thermal considerations are unavoidable in deep geothermal well construction. Temperature and thermal effects, chemical composition of produced fluids, and rate of production or pressure depletion pose significant challenges to well casing and design. Nick Cameron, reservoir characterization manager at BP and leader of the supermajor’s studies into geothermal energy, said his company is using corporate data, geological understanding, and oil and gas expertise and experience to look at where their technology can reduce risk and drive down the cost of development. “Metallurgical understanding of materials and how they handle heat is crucial to these efforts,” he said. “Fortunately, there have been significant advancements in this area in recent years.” Cameron said that much work is also being done into changing the chemical composition of the fluids that flow through the geothermal reservoirs.


2012 ◽  
Vol 6 (3-4) ◽  
pp. 125-130
Author(s):  
Tünde Jenei

The University of Debrecen, Faculty of Engineering, has been conducting a research program in geothermal energy since 2008. This program enabled me to devise an analytical study of the monetary and non-monetary criteria of geothermal projects. The monetary criteria of a region or a location for geothermal energy production cover the investment costs of the surface installations and the cost of the drillings. Non-monetary criteria include the geological and geothermal evaluations of a reservoir and the evaluation of consumer potential. This paper represents a small part of the larger study and focuses on consumer potential.


1995 ◽  
Vol 34 (03) ◽  
pp. 289-296 ◽  
Author(s):  
B. H. Sielaff ◽  
D. P. Connelly ◽  
K. E. Willard

Abstract:The development of an innovative clinical decision-support project such as the University of Minnesota’s Clinical Workstation initiative mandates the use of modern client-server network architectures. Preexisting conventional laboratory information systems (LIS) cannot be quickly replaced with client-server equivalents because of the cost and relative unavailability of such systems. Thus, embedding strategies that effectively integrate legacy information systems are needed. Our strategy led to the adoption of a multi-layered connection architecture that provides a data feed from our existing LIS to a new network-based relational database management system. By careful design, we maximize the use of open standards in our layered connection structure to provide data, requisition, or event messaging in several formats. Each layer is optimized to provide needed services to existing hospital clients and is well positioned to support future hospital network clients.


2017 ◽  
Vol 41 (S1) ◽  
pp. s834-s834 ◽  
Author(s):  
S. Khouadja ◽  
R. Ben Soussia ◽  
S. Younes ◽  
A. Bouallagui ◽  
I. Marrag ◽  
...  

IntroductionTreatment resistance to clozapine is estimated at 40–70% of the treated population. Several clozapine potentiation strategies have come into clinical practice although often without evidence-based support.ObjectiveThe aim of our work was to identify the potentiation strategies in ultra-resistant schizophrenia depending on the subtype of schizophrenia.MethodologyThis is a prospective study conducted on patients with the diagnosis of schizophrenia, based on DSM-IV-TR criteria, and hospitalized in the psychiatric department of the university hospital in Mahdia, Tunisia. The study sample consisted of patients meeting the resistant schizophrenia criteria as defined by national institute for clinical excellence (NICE), and the prescription of clozapine for 6 to 8 weeks was shown without significant improvement.Resultswe have collected 10 patients. The mean serum level of clozapine was 462.25 mg/L. The potentiation strategies were different depending on the subtype of schizophrenia. For the undifferentiated schizophrenia, we have chosen ECT sessions. For the disorganized schizophrenia, we opted for amisulpiride and aripiprazole. For the paranoid forms, we have chosen the association of risperidone and ECT. A psychometric improvement was noted in BPRS ranging from 34 to 40%.ConclusionEvery potentiation strategy entails a cost, whether it is an additional monetary cost, adverse effects or greater stress to caregivers. The cost/benefit equation should be thoroughly evaluated and discussed before commencing a strategy.Disclosure of interestThe authors have not supplied their declaration of competing interest.


2021 ◽  
Author(s):  
Ubedullah Ansari ◽  
Najeeb Anjum Soomro ◽  
Farhan Ali Narejo ◽  
Shafquat Ali Baloch ◽  
Faiz Ali Talpur

Abstract The middle eastern countries including United Arab Emirates (UAE) have enjoyed the energy production from hydrocarbon resource for a very long period. Indeed, now various countries in this region has shifted to alternative resources of power generation with cheaper and cleaner sources. Geothermal is the top of the list among those sources. Therefore, this study presents an ultimate model converting abandoned oil and gas wells into subsurface geothermal recovery points. Fundamentally, this study offers a geo-thermo-mechanical model of abandoned wellbore which can help in developing an optimistic geothermal energy not only from subsurface thermal reserve but also from abandoned casing and pipes installed in Wellbores. In this approach the source of heat is thermally active rock formations and the metallic pipes that are present in wellbores drilled through hot dry rocks. In the model the already drilled wells are incorporated as medium of heat flow in which water in injected and brought back to surface along with thermal impact. The results of this study revealed that, at the depth of 6000 m of high temperature wellbore the temperature is above 85°C and at this temperature the metallic casings further rise the reserve temperature thus the conversion of water into steam can be processed easily. Moreover, at high depths the stability of wellbore is also issue in high temperature formation, so mechanical model suggests that injection of water and conversion into steam in already cased wellbore can sustain up to 6 MPa stress at around 100C. Thus, the geo-thermo-mechanical model of wellbore will illustrate the possibility of converting water into steam and it will also reveal the average amount of heat that can be generated from a single well. henceforth, the thermal recovery from abandoned wells of UAE is best fit solution for clean energy. The abandoned wells are used as conduit to transport heat energy from subsurface by using water as transport medium, as water at surface temperature is injected in those wellbores and let thermal energy convert that water into steam. Later the steam is returned to surface and used as fuel in turbines or generators.


2021 ◽  
Vol 73 (07) ◽  
pp. 50-50
Author(s):  
Robello Samuel

How we think about the future of the pipe industry must evolve. How must tubular design and manufacturing change as we transition to clean energy? Geothermal energy is an area that needs attention and, further, needs very specific attention on tubulars. Tubulars are an important component in the construction of geothermal wells, and we must align our requirements for geothermal energy. Some of the main challenges encountered in geothermal wells are corrosion and scaling. Moreover, temperature becomes a major consideration for tubulars, even more so with the temperature excursion during geothermal production. Perhaps the critical aspect in the design of the geothermal wells involves casing selection and design. Beyond manufacturing casing pipes to withstand these problems, considering the manufacturing of other components, such as connections, float collars, and float shoes, also is essential. Thermal expansion and thermal excursion of casings are well-integrity concerns; thus, casing design is important for long-term sustainability of geothermal wells. Apart from thermal simulations, guidelines and software are needed to undergird the designs to withstand not only temperature excursions but also thermomechanical and thermochemical loadings. Engineered nonmetallic casings also provide an alternative solution because they provide the desired strength and corrosion resistance in addition to meeting the goals of sustainability. Undoubtedly, the future of the tubular industry is going to be revitalized. The question now is how we can retrofit existing abandoned wells for this purpose. Recommended additional reading at OnePetro: www.onepetro.org. SPE 199570 - Special Considerations for Well-Tubular Design at Elevated Temperatures by Gang Tao, C-FER Technologies, et al.


2021 ◽  
Author(s):  
Junichi Sugiura ◽  
Ramon Lopez ◽  
Francisco Borjas ◽  
Steve Jones ◽  
John McLennan ◽  
...  

Abstract Geothermal energy is used in more than 20 countries worldwide and is a clean, reliable, and relatively available energy source. Nevertheless, to make geothermal energy available anywhere in the world, technical and economic challenges need to be addressed. Drilling especially is a technical challenge and comprises a significant part of the geothermal development cost. An enhanced geothermal system (EGS) is a commercially viable thermal reservoir where two wells are interconnected by some form of hydraulic stimulation. In a commercial setting, fluid is injected into this hot rock and passes between wells through a network of natural and induced fractures to transport heat to the surface system for electricity generation. To construct EGS wells, vertical and directional drilling is necessary with purpose-built drilling and steering equipment. This is an application where oil-and-gas drilling tools and techniques can be applied. A recent well, 16A(78)-32, drilled as part of the US Department of Energy's (DOE's) Utah Frontier Observatory for Research in Geothermal Energy (FORGE) program, highlights some of the technical challenges, which include drilling an accurate vertical section, a curve section, and a 5300-ft 65° tangent section in a hard granitic formation at temperatures up to 450°F (232°C). Extensive downhole temperature simulations were performed to select fit-for-purpose drilling equipment such as purely mechanical vertical drilling tools, instrumented steerable downhole motors, measurement-while-drilling (MWD) tools, and embedded high-frequency drilling dynamics recorders. Downhole and surface drilling dynamics data were used to fine- tune bit design and motor power section selection and continuously improve the durability of equipment, drilling efficiency, and footage drilled. Drilling optimization techniques used in oil and gas settings were successfully applied to this well, including analysis of data from drilling dynamics sensors embedded in the steerable motors and vertical drilling tools, surface surveillance of mechanical specific energy (MSE), and adopting a drilling parameter roadmap to improve drilling efficiency to minimize drilling dysfunctions and equipment damages. Through drilling optimization practices, the instrumented steerable motors with proper bit selections were able to drill more than 40 ft/hr on average, doubling the rate of penetration (ROP), footage, and run length experienced in previous granite wells. This paper presents a case study in which cutting-edge oil-and-gas drilling technologies were successfully applied to reduce the geothermal well drilling time by approximately half.


1982 ◽  
Vol 26 (3) ◽  
pp. 279-291 ◽  
Author(s):  
Stuart Macdonald ◽  
Tom Mandeville ◽  
Don Lamberton

This paper is based on a research report published at the University of Queensland in November 1980, which emanated from research commissioned by the University's Research Committee and carried out by the authors. The study was concerned with the problem of distributing resources available for research and concluded that there was not an efficient use of such resources in the University of Queensland. Part of the study considered attempts to increase efficiency by funding those research projects which seemed to possess most merit. Such policy is becoming more common in Australian universities and this is understandable during a period of financial stringency. However, the policy seems to ignore the substantial costs associated with applying for merit grants, and to assume that any scheme funding the most deserving research automatically improves the efficiency of research funding. That is not necessarily so. Most research funding in Australian universities is provided in the form of staff salaries. When staff time is occupied by the merit application and assessment process, it is not available for research. Consequently there is a cost to research, a cost that is not widely appreciated and one which may well exceed the benefits of ill-considered merit schemes.


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