Chattanooga Shale, underlying some 40,000 square miles in the southeastern United States, is considered to be a potentially large, low-grade source of uranium. The area in and near Dekalb County, Tennessee, appears to be the most likely site for commercial development. This paper deals with the mine design, mining procedures, equipment requirements, and operating maintenance costs for an underground mining complex capable of producing 100,000 tons of Chattanooga Shale per day for delivery to a beneficiation process
This volume characterizes the major baseline environmental features of the Chattanooga Shale study and projects the effects which may accrue from implementation of a large scale development to recover uranium from the shale. Environmental, socioeconomic, and regulatory impacts are covered. The prototype project is located in Dekalb County in Tennessee
This report describes the engineering, feasibility, economics, and environmental aspects of exploitation of Chattanooga Shale to recover U, synthetic crude oil, and byproduct Th, NH3, S, Mo, V, Ni, and Co. It is concluded that the shale is a potential source of U, energy, and byproduct metals. This volume of the report covers the engineering description, feasibility, and economics of exploitation of the shale
This report describes the engineering, feasibility, economics, and environmental aspects of exploitation of Chattanooga Shale to recover U, synthetic crude oil, and byproduct Th, NH/sub 3/, S, Mo, V, Ni, and Co. It is concluded that the shale is a potential source of U, energy, and byproduct metals. This volume of the report covers the engineering description, feasibility, and economics of exploitation of the shale. (DLC)
This volume contains five appendixes: Chattanooga Shale preliminary mining study, soils data, meteorologic data, water resources data, and biological resource data. The area around DeKalb County in Tennessee is the most likely site for commercial development for recovery of uranium
This volume characterizes the major baseline environmental features of the Chattanooga Shale study and projects the effects which may accrue from implementation of a large scale development to recover uranium from the shale. Environmental, socioeconomic, and regulatory impacts are covered. The prototype project is located in Dekalb County in Tennessee. (DLC)
This volume contains five appendixes: Chattanooga Shale preliminary mining study, soils data, meteorologic data, water resources data, and biological resource data. The area around DeKalb County in Tennessee is the most likely site for commercial development for recovery of uranium. (DLC)
Li, Yifan; Schieber, Juergen
The Devonian Chattanooga Shale contains an uppermost black shale interval with dispersed phosphate nodules. This interval extends from Tennessee to correlative strata in Kentucky, Indiana, and Ohio and represents a significant period of marine phosphate fixation during the Late Devonian of North America. It overlies black shales that lack phosphate nodules but otherwise look very similar in outcrop. The purpose of this study is to examine what sets these two shales apart and what this difference tells us about the sedimentary history of the uppermost Chattanooga Shale. In thin section, the lower black shales (PBS) show pyrite enriched laminae and compositional banding. The overlying phosphatic black shales (PhBS) are characterized by phosbioclasts, have a general banded to homogenized texture with reworked layers, and show well defined horizons of phosphate nodules that are reworked and transported. In the PhBS, up to 8000 particles of P-debris per cm2 occur in reworked beds, whereas the background black shale shows between 37-88 particles per cm2. In the PBS, the shale matrix contains between 8-16 phosphatic particles per cm2. The shale matrix in the PhBS contains 5.6% inertinite, whereas just 1% inertinite occurs in the PBS. The shale matrix in both units is characterized by flat REE patterns (shale-normalized), whereas Phosbioclast-rich layers in the PhBS show high concentrations of REEs and enrichment of MREEs. Negative Ce-anomalies are common to all samples, but are best developed in association with Phosbioclasts. Redox-sensitive elements (Co, U, Mo) are more strongly enriched in the PBS when compared to the PhBS. Trace elements associated with organic matter (Cu, Zn, Cd, Ni) show an inverse trend of enrichment. Deposited atop a sequence boundary that separates the two shale units, the PhBS unit represents a transgressive systems tract and probably was deposited in shallower water than the underlying PBS interval. The higher phosphate content in the PhBS is
Impermeable rock units, preferably at least 500 feet thick and lying 1000 to 3000 feet below land surface, were sought in the region consisting roughly of the western /sup 3///sub 5/ths of Tennessee and the northern /sup 3///sub 5/ths of Alabama and Mississippi. All rock sequences, Cambrian through Eocene, were examined in varying detail, except the Cretaceous Selma Chalk and except the diapiric salt. These rocks were studied for their relative impermeable homogeneity, their continuity, their background of structural and seismic stability and their hydrologic associations. The Central Mississippi Ridge of north-central Mississippi is overlain by a long-stable mass of Porters Creek Clay 500-700 feet thick, in an area roughly 50-60 miles wide and about 150 miles long. The Yazoo Clay, where best developed in the west-central and southwest part of Mississippi, is in the 400-500 foot thickness range, but locally exceeds 500 feet. The entire area mapped is underlain by the Louann Salt which has produced many deep-seated salt domes and numerous piercement salt domes. Salt flow has complicated shallow structural geology throughout that area. The Chattanooga Shale rarely exceeds 60 feet in thickness in the region studied and is generally much thinner and is absent in many places. In the lower part of the Middle Ordovician (Ottawa Megagroup), the Murphreesboro and associated dense limestones appear to offer a potential disposal unit 250-400 feet thick, having the advantages of rock competency and freedom from association with prolific aquifers in the overburden or beneath. Other less conspicuous stratigraphic units are reviewed.
Impermeable rock units, preferably at least 500 feet thick and lying 1000 to 3000 feet below land surface, were sought in the region consisting roughly of the western 3/5ths of Tennessee and the northern 3/5ths of Alabama and Mississippi. All rock sequences, Cambrian through Eocene, were examined in varying detail, except the Cretaceous Selma Chalk and except the diapiric salt. These rocks were studied for their relative impermeable homogeneity, their continuity, their background of structural and seismic stability and their hydrologic associations. The Central Mississippi Ridge of north-central Mississippi is overlain by a long-stable mass of Porters Creek Clay 500-700 feet thick, in an area roughly 50-60 miles wide and about 150 miles long. The Yazoo Clay, where best developed in the west-central and southwest part of Mississippi, is in the 400-500 foot thickness range, but locally exceeds 500 feet. The entire area mapped is underlain by the Louann Salt which has produced many deep-seated salt domes and numerous piercement salt domes. Salt flow has complicated shallow structural geology throughout that area. The Chattanooga Shale rarely exceeds 60 feet in thickness in the region studied and is generally much thinner and is absent in many places. In the lower part of the Middle Ordovician (Ottawa Megagroup), the Murphreesboro and associated dense limestones appear to offer a potential disposal unit 250-400 feet thick, having the advantages of rock competency and freedom from association with prolific aquifers in the overburden or beneath. Other less conspicuous stratigraphic units are reviewed
The Chattanooga-Hamilton County Air Pollution Control Bureau (CHCAPCB), the United States Environmental Protection Agency Region 4 (Region 4), and other stakeholders, in a cooperative effort, conducted an air toxics study in the Chattanooga area (city population approximately 285...
Dorris, John Peter
The purpose of this quantitative study was to identify the workforce skills perceived to be critical in the Chattanooga region, and to explore how colleges and businesses can partner to effectively develop those skills. Data from a June 2011 survey of workforce stakeholders in the Chattanooga region were analyzed. The 78 survey respondents…
Hussar, Erika; Richards, Sean; Lin, Zhi-Qing; Dixon, Robert P; Johnson, Kevin A
South Chattanooga has been home to foundries, coke furnaces, chemical, wood preserving, tanning and textile plants for over 100 years. Most of the industries were in place before any significant development of residential property in the area. During the 1950s and 1960s, however, the government purchased inexpensive property and constructed public housing projects in South Chattanooga. Many neighborhoods that surround the Chattanooga Creek were previous dumping grounds for industry. Polycyclic aromatic hydrocarbons (PAHs) comprised the largest component of the dumping and airborne industrial emissions. To address the human exposure to these PAHs, a broad study of South Chattanooga soil contaminant concentrations was conducted on 20 sites across the city. Sixteen priority pollutant PAHs were quantified at two depths (0-10cm and 10-20cm) and compared against reference site soils, as well as to soils from industrially-impacted areas in Germany, China, and the US. From these data, the probability that people would encounter levels exceeding EPA Residential Preliminary Remediation Goals (PRG) was calculated. Results indicate that South Chattanooga soils have relatively high concentrations of total PAHs, specifically Benzo[a]pyrene (B[a]P). These high concentrations of B[a]P were somewhat ubiquitous in South Chattanooga. Indeed, there is a high probability (88%) of encountering soil in South Chattanooga that exceeds the EPA PRG for B[a]P. However, there is a low probability (15%) of encountering a site with ∑PAHs exceeding EPA PRG guidelines. PMID:23243323
Five shales were examined as part of the Sedimentary Rock Program evaluation of this medium as a potential host for a US civilian nuclear waste repository. The units selected for characterization were the Chattanooga Shale from Fentress County, Tennessee; the Pierre Shale from Gregory County, South Dakota; the Green River Formation from Garfield County, Colorado; and the Nolichucky Shale and Pumpkin Valley Shale from Roane County, Tennessee. The micromorphology and structure of the shales were examined by petrographic, scanning electron, and high-resolution transmission electron microscopy. Chemical and mineralogical compositions were studied through the use of energy-dispersive x-ray, neutron activation, atomic absorption, thermal, and x-ray diffraction analysis techniques. 18 refs., 12 figs., 2 tabs
One objective of the Sedimentary Rock Program at the Oak Ridge National Laboratory has been to examine end-member shales to develop a data base that will aid in evaluations if shales are ever considered as a repository host rock. Five end-member shales were selected for comprehensive characterization: the Chattanooga Shale from Fentress County, Tennessee; the Pierre Shale from Gregory County, South Dakota; the Green River Formation from Garfield County, Colorado; and the Nolichucky Shale and Pumpkin Valley Shale from Roane County, Tennessee. Detailed micromorphological and mineralogical characterizations of the shales were completed by Lee et al. (1987) in ORNL/TM-10567. This report is a supplemental characterization study that was necessary because second batches of the shale samples were needed for additional studies. Selected physical, chemical, and mineralogical properties were determined for the second batches; and their properties were compared with the results from the first batches. Physical characterization indicated that the second-batch and first-batch samples had a noticeable difference in apparent-size distributions but had similar primary-particle-size distributions. There were some differences in chemical composition between the batches, but these differences were not considered important in comparison with the differences among the end-member shales. The results of x-ray diffraction analyses showed that the second batches had mineralogical compositions very similar to the first batches. 9 refs., 9 figs., 4 tabs
... National Park Service Minor Boundary Revision at Chickamauga and Chattanooga National Military Park AGENCY: National Park Service, Interior. ACTION: Notification of boundary revision. SUMMARY: Notice is hereby given... Military Park is modified to include an additional 13.75 acres of land identified as Tract 11-109....
This Power Point presentation comments the evolution of the World population, GDP and energy demand, the evolution of the nuclear mix by 2030, the oil and gas reserves. Then, the author defines the different hydrocarbon classes (conventional gas and oil, heavy oil, oil shale), describes how natural gas is trapped in low permeability rocks, the specific production techniques (horizontal drilling and hydraulic fracturing), and recalls the well architecture. Then, he more precisely presents the various aspects of hydraulic fracturing, outlines and comments the challenges raised by this technique regarding industry ability and means and water quality and consumption. He comments the geographical distribution of gas resources, and the share of shale gases, the impact on climate, and the European shale gas production potential
Tourtelot, Harry A.
The Sharon Springs member of the Pierre shale of Cretaceous age, a hard black organic-rich shale similar to the Chattanooga shale, is radioactive throughout central and western South Dakota, most of Nebraska, northern Kansas, and northeastern Colorado. In the Missouri River valley, thin beds of the shale contain as much as 0.01 percent uranium. Beds as much as 20 feet thick or more have a radioactivity of about 0.01 percent equivalent uranium in southwestern Nebraska according to interpretation of gamma-ray well logs. The radioactivity and uranium content is highest in the Missouri River valley in South Dakota and in southwestern Nebraska where the shale rests disconformably on the underlying Niobrara formation of Cretaceous age. Near the Black Hills, and in the area to the north, the shale of the Sharon Springs member rests on a wedge of the Gammon ferruginous member of the Pierre, which is represented by a disonformity to the east and south, and the radioactivity of the shale is low although greater than that of over-lying strata. The shale also contains a suite of trace elements in which arsenic, boron, chromium, copper, molybdenum, nickel, selenium, and vanadium are conspicuous. Molybdenum and tin are less abundant in the Sharon Springs than in similar shales of Palezoic age and silver and selenium are more abundant. In the Great Plains region, the upper 30-50 feet of Cretaceous shales overlain unconformably by the White River group of Oligocene age has been altered to bright-colored material. This altered zone is chiefly the result of pre-Oligocene weathering although post-Oligocene ground water conditions also have affected the zone. The greatest radioactivity occurs in masses of unaltered shale measuring about 1 x 4 feet in cross section included in the lower part of the altered zone. Where the zone is developed on shale and marl of the Niobrara formation, parts of the included unaltered shale contains as much as 0.1 percent equivalent uranium and 0
Oil shale is undoubtedly an excellent energy source that has great abundance and world-wide distribution. Oil shale industries have seen ups and downs over more than 100 years, depending on the availability and price of conventional petroleum crudes. Market forces as well as environmental factors will greatly affect the interest in development of oil shale. Besides competing with conventional crude oil and natural gas, shale oil will have to compete favorably with coal-derived fuels for similar markets. Crude shale oil is obtained from oil shale by a relatively simple process called retorting. However, the process economics are greatly affected by the thermal efficiencies, the richness of shale, the mass transfer effectiveness, the conversion efficiency, the design of retort, the environmental post-treatment, etc. A great many process ideas and patents related to the oil shale pyrolysis have been developed; however, relatively few field and engineering data have been published. Due to the vast heterogeneity of oil shale and to the complexities of physicochemical process mechanisms, scientific or technological generalization of oil shale retorting is difficult to achieve. Dwindling supplied of worldwide petroleum reserves, as well as the unprecedented appetite of mankind for clean liquid fuel, has made the public concern for future energy market grow rapidly. the clean coal technology and the alternate fuel technology are currently of great significance not only to policy makers, but also to process and chemical researchers. In this book, efforts have been made to make a comprehensive text for the science and technology of oil shale utilization. Therefore, subjects dealing with the terminological definitions, geology and petrology, chemistry, characterization, process engineering, mathematical modeling, chemical reaction engineering, experimental methods, and statistical experimental design, etc. are covered in detail
To identify the duration of oil shale utilization in Estonia the amount of mineable resource and present demand for oil shale must be taken into account. As of beginning of 1999, by economical and environmental criteria active i.e. mineable resource of Estonia oil shale deposit is accounted for 1.5 billion tonnes, which is almost as much as has been mined out from the hole exhausted area. Considering the present oil shale production output together with production losses and written of resource (total ca 15-17 million tonnes per annum), the mineable (active) resource of mine fields (0.59 billion tonnes) guarantee oil shale mining for minimum 35 years. In the future Aidu, Sirgala and Narva opencasts will be transferred into underground mines due to increasing thickness of overburden. Supplementary resource for operating mines and quarries will be obtained on the account of Ojamaa, Seli and Permiskuela exploration fields. Mining licence should be obtained for areas with favourable conditions in Aidu and Sirgala mine fields for which presently the allotment is missing. Taking into account the possible additional resources and somewhat smaller oil shale output, the reserves will last additional 10-15 years. Closing down old mines should be done after using the active reserves in places already prepared for winning, since mining the latter via other mines is hardly possible. In terms of establishing a new opencast, Poehja-Kivioeli exploration is most suitable, while establishing of new underground mines would be expedient in Uus-Kivioeli, Sonda and Puhatu exploration fields. In case oil shale production decreases in the nearest future, majority of the resources presently accounted as mineable may remain unused. Several peak periods can be distinguished in oil shale utilization and exploration, e.g. turn of the 19th and 20th century, World War II and first post-war years, world-wide energy crisis in 1070-80. During these years oil shale exploration was carried out in
China has abundant oil shale resources, of the Early Silurian to Neogene age, the most important being the Tertiary period. The proved oil shale reserves in Fushun amount to 3.6 billion t, in Maoming 4.1 billion t. In Fushun, oil shale is produced by open-pit mining as a byproduct of coal, in Maoming it is also mined in open pits, but without coal. In China, scale oil has been produced from oil shale for 60 years. Annual production of crude shale oil amounts to about 200 000 t. The production costs of shale oil are lower than the price of crude petroleum on the world market. China has accumulated the experience and technologies of oil shale retorting. The Fushun type retort has been elaborated, in which the latent and sensible heat of shale coke is well utilized. But the capacity of such retort is relatively small, therefore it is suitable for use in small or medium oil plants. China has a policy of steadily developing shale oil industry. China is conducting oil shale research and developing oil shale processing technology. Much attention is being pay ed to the comprehensive utilization of oil shale, shale oil, and to environmental problems. In China, oil shale is mostly used for producing shale by retorting, attention will also be paid to direct combustion for power generation. Great achievements in oil shale research have been made in the eighties, and there will be a further development in the nineties. (author), 12 refs., 3 tabs
Thermal conductivity and heat capacity measurements were made on samples of Devonian shale, Pierre shale, and oil shale from the Green River Formation. Thermal expansion measurements were made on selected samples of Devonian shale. Measurements were obtained over the temperature range of ambient to 473 K. Average values for thermal conductivity and heat capacity for the samples studied were within two standard deviations of all data over this temperature range. 15 refs., 12 figs., 4 tabs
A 'coutant' carbon steel combustion chamber cooled by water jacket was conslructed to burn diesel fuel and mixlure of shale oil and diesel fuels. During experimental work nir fuel ratio was determined, temperaturces were measured using Chromel/ Almel thermocouple, finally the gasous combustion product analysis was carricd out using gas chromatograph technique. The constructed combustion chamber was operating salisfactory for several hours of continous work. According to the measurements it was found that: the flame temperature of a mixture of diesel and shale oil fuels was greater than the flame temperature of diesel fuel. and the sulfer emissious of a mixture of diesel and shale oil fuels was higher than that of diesel fuel. Calculation indicated that the dry gas energy loss was very high and the incomplete combustion energy loss very small. (author). 23 refs., 35 figs
The low prices of crude oil have continued to retard the commercial development of oil shale and other syn fuels. Although research funds are more difficult to find, some R and D work by industry, academia, and governmental agencies continues in the United States and in other parts of the world. Improvements in retorting technology, upgrading oil-shale feedstock, and developing high-value niche-market products from shale oil are three notable areas of research that have been prominent for the past several years. Although the future prices of conventional crude cannot be predicted, it seems evident that diminishing supplies and a burgeoning world population will force us to turn to alternate fossil fuels as well as to cleaner sources of non-fossil energy. (author)
This book aims at exploring all aspects of the shale gas issue: geological data, environmental impacts, financial aspects and economical impacts of shale gas exploitation. It compares the available information with the field reality and defeats the dogmatic mirages. The research and compilation work carried out by the author make this book a reference in the domain of shale gas exploitation
This article comments the recent development of shale gas exploration and exploitation in Poland, the associated political decisions, the locations and the involved companies, and the project of creation of a national operator of energy resources. It also evokes the reactions of the European Union in front of these Polish developments, notably the adoption of a proposal for introducing a mandatory environmental impact study before exploring a site. It comments a visit made by French officials (a parliamentary body) in Poland, outlines some problems faced to precisely assess the cost of shale gas exploitation, and comments technological developments in Poland which therefore represents a reference and a test
This bibliographical note presents a book in which the author criticizes all the statements of lobbies supporting shale gas exploitation with reference to job creations, energy price and competition, energy supply independence. He discusses the consequences of a legal authorization of this exploitation. His critics are notably based on the North-American experience
This article outlines that, even if it would be allowed, the exploitation of shale gas in France would need ten years to start, and no one can say what would be our needs then and what would be the situation of the gas market at that time. Even if the government decided to forbid hydraulic fracturing, there could be some opportunity for experimentation with a search for alternative technology. The article notices that risks associated with hydraulic fracturing and extraction of non conventional hydrocarbons, i.e. water pollution and consumption and land use, are variously perceived in different European countries (Germany, Romania, Poland) where important American actors are present (Chevron, Exxon) to exploit shale gases. In the USA, the economic profitability seems in fact to rapidly decrease
Seaton, A; Lamb, D; Brown, W. R.; Sclare, G.; Middleton, W G
Four patients are described in whom pneumoconiosis was diagnosed towards the end of a lifetime's work in shale mines. All developed complicated pneumoconiosis, diagnosed in two cases at necropsy, in one by lobectomy, and in one radiologically. Two of the patients were found at necropsy also to have peripheral squamous lung cancer.The clinical and histological features of the disease resembled the pneumoconioses of coalminers and kaolin workers and the lungs of three of the patients were shown...
Although still only produced in North America, shale gas has had a strong influence on the world energy scene over the last five years. Its present and future impact on the gas market cannot be ignored, in a context where all observers are forecasting significant demand growth for gas over the coming decades. Although classified as unconventional gas, the origin and nature of shale gas are the same as for natural gas. It is the consequence of the characteristics of the rock that contains it and its production resorts to the systematic use of techniques that have long been known and developed by the gas industry in other applications. Exploration aimed at evaluating its potential outside the USA and Canada is ongoing notably in South America, Europe and Asia. This will serve first to reduce uncertainty linked to the very existence of shale gas as a resource and to the characteristics of the geological formations containing it. The potential plays must then integrate the constraints relating to water management, the protection of the water table and management of surface operations, taking account of their interaction with other assorted stakeholders. (author)
To distill oil shales, cannel coals, and other carbonaceous materials for the extraction therefrom of hydrocarbons and volatile nitrogenous compounds, hard non-condensable gases from the condensers and scrubbers are withdrawn by blowers and admixed with burnt gases, obtained through conduits from the flues of heaters, and forced downwardly through horizontal chambers, connected by vertical conduits, of the heaters and delivered into the retort beneath the grate. Passing upwardly through the charge they vaporize the volatile substances in the shale, and a suction pump removes the vapors from the top of the retort. Immediately they are produced and at substantially the same temperature as that at which they emanate, thus preventing cracking of the oil vapors and condensation of the oil at the top of the retort. The amount of burnt flue gas admixed with the hard gases is regulated by two valves until a required uniform temperature is obtained. A generator supplies producer gas to a heater at the commencement of the retorting operation for circulation through the shale charge to initially produce oil vapors. The generator is connected by a pipe to the gas conduit leading to blowers.
The article gives an overview about the oil shale deposits and industry in Estonia, the quality of commercial oil shale and the mining activities are also discussed. The development of power and heat production from oil shale is described
Highlights: • The whole formation process of shale oil might be divided into four stages. • Higher ash/shale mass ratio intensified the cracking and coking of shale oil. • Ash/shale ratio of 1:2 was recommended for oil shale fluidized bed retort with fine oil-shale ash as solid heat carrier. - Abstract: For exploring and optimizing the oil shale fluidized bed retort with fine oil-shale ash as a solid heat carrier, retorting experiments of oil shale and fine oil-shale ash mixtures were conducted in a lab-scale retorting reactor to investigate the effects of fine oil-shale ash on shale oil. Oil shale samples were obtained from Dachengzi Mine, China, and mixed with fine oil-shale ash in the ash/shale mass ratios of 0:1, 1:4, 1:2, 1:1, 2:1 and 4:1. The experimental retorting temperature was enhanced from room temperature to 520 °C and the average heating rate was 12 °C min−1. It was found that, with the increase of the oil-shale ash fraction, the shale oil yield first increased and then decreased obviously, whereas the gas yield appeared conversely. Shale oil was analyzed for the elemental analysis, presenting its atomic H/C ratio of 1.78–1.87. Further, extraction and simulated distillation of shale oil were also conducted to explore the quality of shale oil. As a result, the ash/shale mixing mass ratio of 1:2 was recommended only for the consideration of increasing the yield and quality of shale oil
Plans for the continued use of oil shale may lead the development of this country into an impasse. To this day no plans have been made for transition from the use of energy based on fossil fuels to that based on renewable resources. Without having any clear strategic plan politicians have been comforting both themselves and the population with promises to tackle the problem when the right time comes. Today the only enterprise whose cash flows and capital would really make it possible to reform the power industry is the firm Eesti Energia (Estonian Energy). However, its sole present shareholder - the state - prefers the sale of the firm's shares to carrying out a radical reform. At the same time, local consumers are likely to rather be willing to pay for the expensive electric energy produced from renewable resources than for that produced from fossil fuels, the price of which will also remain high due to the pollution tax. Practically it is impossible to buy a globally balanced environment for money - pollution taxes are but punitive mechanisms. The investments made into the oil-shale industry will also reinforce the cultural distance of North-East Estonia from the rest of Estonia - the uniform and prevalently Russian-speaking industrial area will be preserved as long as capital will continue to flow into the oil shale industry concentrated there. The way out would be for industries to make wider use of ecological and ecosystemic technologies and for the state to enforce ecologically balanced economic and social policies. (author)
The US Bureau of Mines publication presents the results of investigations into the fire and explosion hazards of oil shale rocks and dust. Three areas have been examined: the explosibility and ignitability of oil shale dust clouds, the fire hazards of oil shale dust layers on hot surfaces, and the ignitability and extinguishment of oil shale rubble piles. 10 refs., 54 figs., 29 tabs.
Shale gas refers to gas found in coal seems. In Alberta, shale gas is regulated in the same manner as natural gas. Existing royalty and tenure rules apply. Shale gas development is in its early stage, but interest is increasing due to the growing demand for natural gas, higher prices and maturing conventional supply. Although the estimated gas in place is high, with potential targets in Cretaceous, Jurassic, Triassic, Mississippian and Devonian shales, the actual recoverable amount is not currently known. A map illustrating the distribution of coal zones with shale gas potential in Alberta was presented along with a review of plans to provide information on shale gas resource evaluation. The information would reveal how it is defined, where it is located and the resource potential. The Alberta Geological Survey will create geological and geochemical maps showing areas of current shale gas production. Regulations and policies that address mineral and land tenure issues were presented along with key principles of Alberta's royalty framework. figs
Shale and oil gases are in the center of a national debate in France. They are accused of being responsible of aquifers and ground pollution, of air poisoning, of earthquake triggering and so on. Opponents to shale gas exploitation have won the first round but the potential beneficiaries, the industrialists and politics, have not given up. This book unravels the existing connections between the administration, industrial and political powers and demonstrates why the shale gases exploitation projects are not abandoned despite their proven harmful impact on the environment. (J.S.)
The rate of recovery, amount of recovery and/or the nature of the petroleum materials that are recovered from a subterranean oil-shale formation are improved by use of at least one phenolic compound having unique oil-extracting properties. At least one well-bore hole is drilled into a permeable zone formed within a subterranean oil-shale formation and an aromatic organic Bronsted acid, such as a phenolic compound is circulated through per se or in a fluid carrier. Shale oil and circulating extracting fluid material are then recovered from the permeable zone and the shale oil is separated from the extracting material. The formation should be preheated prior to injection or the circulating fluid should be injected hot in carrying out this process. (6 claims)
John Shelton; Mike D. Bumaman; Wenwu Xia; Nathaniel Harding
Natural gas production from shale formations is growing exponentially in the United States. This paper introduces the five major shale formations in the United States and the technologies used to produce them. The Barnett, Haynesville,Fayetteville, Woodford, and Marcellus combined hold an estimated 978 trillion cubic feet of total gas reserves. These findings along with recent technological advances in horizontal drilling and completion methods have transformed the natural gas exploration and production industry in the U.S. and have fundamentally changed the U.S. energy picture. Specifically this paper states that the United States through the utilization of natural gas from shale can reduce its carbon emissions and can become more energy self-sufficient. Finally, the Harding & Shelton Group states in this paper that the opportunity to locate and produce shale gas in China is very similar to that which has taken place in the United States.
Broussard, P. H.; Burch, J. L.; Drost, E. J.; Stein, R. J. (Inventor)
A penetrometer for coal-shale interface detection is presented. It is used with coal cutting equipment consisting of a reciprocating hammer, having an accelerometer mounted thereon to measure the impact of the hammer as it penetrates the ceiling or floor surface of a mine. Additionally, a pair of reflectometers simultaneously view the same surface, and the outputs from the accelerometer and reflectometers are detected and jointly registered to determine when an interface between coal and shale is being cut through.
Reid, H., Jr. (Inventor)
A coal-shale interface detector for use with coal cutting equipment is described. The detector consists of a reciprocating hammer with an accelerometer to measure the impact of the hammer as it penetrates the ceiling or floor surface of a mine. Additionally, a pair of reflectometers simultaneously view the same surface, and the outputs from the accelerometer and reflectometers are detected and jointly registered to determine when an interface between coal and shale is being cut through.
Chandler, Michael R.; Meredith, Philip G.; Brantut, Nicolas; Crawford, Brian R.
The use of hydraulic fracturing to recover shale gas has focused attention on the fundamental fracture properties of gas-bearing shales, but there remains a paucity of available experimental data on their mechanical and physical properties. Such shales are strongly anisotropic, so that their fracture propagation trajectories depend on the interaction between their anisotropic mechanical properties and the anisotropic in situ stress field in the shallow crust. Here we report fracture toughness measurements on Mancos shale determined in all three principal fracture orientations: Divider, Short Transverse, and Arrester, using a modified short-rod methodology. Experimental results for a range of other sedimentary and carbonate rocks are also reported for comparison purposes. Significant anisotropy is observed in shale fracture toughness measurements at ambient conditions, with values, as high as 0.72 MPa m1/2 where the crack plane is normal to the bedding, and values as low as 0.21 MPa m1/2 where the crack plane is parallel to the bedding. For cracks propagating nonparallel to bedding, we observe a tendency for deviation toward the bedding-parallel orientation. Applying a maximum energy release rate criterion, we determined the conditions under which such deviations are more or less likely to occur under more generalized mixed-mode loading conditions. We find for Mancos shale that the fracture should deviate toward the plane with lowest toughness regardless of the loading conditions.
Shale gas is the residual methane remaining in the mother rock after the formation of a geological reservoir of oil, gas or coal. Till recently shale gas was not exploited because it was too diffuse and too difficult to reach. Now, since about 10 years 2 new drilling techniques have been validated: first the horizontal drilling that consists in drilling a well vertically and then horizontally in the shale layer and secondly the hydraulic fracturing in which a large amount of high pressure water is injected in the shale rock to open pre-existing cracks through which methane will drain. The hydraulic fracturing implies the pollution of large amount of water and is seen as very aggressive on the environment. The horizontal drilling can now be made on long distances up to 8 km which means that a well can be used for several decades. In the Usa there was a boom in gas shale prospecting and exploitation because the law allows the landowner to keep 25% of the underground wealth. In France the law stipulates that hydrocarbons belong to the state. In the Usa some cases of underground water pollution have been revealed, according to some specialists, this pollution is not due to hydraulic fracturing itself because phreatic water layers are far above (between 2000 m and 3000 m) shale layers but would be due to leaks on the vertical well. According to a study the carbon footprint of shale gas would be 33 g of CO2 per million of joules of energy produced while the figure would be 31.9 g for coal. (A.C.)
Cena, R.J. (ed.)
Livermore's oil shale project is funded by two budget authorities, two thirds from base technology development and one third from environmental science. Our base technology development combines fundamental chemistry research with operation of pilot retorts and mathematical modeling. We've studied mechanisms for oil coking and cracking and have developed a detailed model of this chemistry. We combine the detailed chemistry and physics into oil shale process models (OSP) to study scale-up of generic second generation Hot-Recycled-Solid (HRS) retorting systems and compare with results from our 4 tonne-per-day continuous-loop HRS pilot retorting facility. Our environmental science program focuses on identification of gas, solid and liquid effluents from oil shale processes and development of abatement strategies where necessary. We've developed on-line instruments to quantitatively measure trace sulfur and nitrogen compounds released during shale pyrolysis and combustion. We've studied shale mineralogy, inorganic and organic reactions which generate and consume environmentally sensitive species. Figures, references, and tables are included with each discussion.
This paper presents a summary of the key observations and conclusions from the Gas Research Institute's (GRI's) Comprehensive Study Well (CSW) research program conducted in the Devonian Shales of the Appalachian Basin. Initiated in 1987, the CSW program was a series of highly instrumented study wells drilled in cooperation with industry partners. Seven wells were drilled as part of the program. Extensive data sets were collected and special experiments were run on the CSW's in addition to the operator's normal operations, with the objectives of identifying geologic production controls, refining formation evaluation tools, and improving reservoir description and stimulation practices in the Devonian Shales. This paper highlights the key results from the research conducted in the CSW program in the areas of geologic production controls, formation evaluation, stimulation and reservoir engineering, and field operations. The development of geologic, log analysis, and reservoir models for the Shales from the data gathered and analysis, and reservoir models for the Shales from the data gathered and analyzed during the research is discussed. In addition, on the basis of what was learned in the CSW program, GRI's plans for new research in the Devonian Shales are described
The report gives results of a study considering the possibility of using a spent oil shale itself as a water barrier or liner beneath a spent oil shale waste enbankment. Pertinent properties of unburned Tosco II spent shale and an average mixture of Lurgi spent shale have been me...
Ковальський, В.С.; Кіровоградський національний технічний університет; Зубченко, О.М.; НАУ, кафедра технологічного обладнання; Богуслав, М.В.; Комітет молодіжних та дитячих громадських організацій м. Києва
It’s been considered the role of сombustible shales for energetics and chemistry of Ukraine, pointed its layers and done detailed analize of extraction and converting technologies of Combustible shales.
Favero, Valentina; Ferrari, Alessio; Laloui, Lyesse
The development of engineering activities involving shales such as the extraction of shale gas and shale oil, the nuclear waste geological storage and the sequestration of CO2, has led to an increasing interest toward the geomechanical behaviour of this geomaterial. In the context of such engineering applications, a deep understanding of the hydro-mechanical behaviour of shales is of primary significance. The water retention mechanisms play a major role in either fluid trapping due to the cap...
Herce, J.A.; O' Brien, S.M.; Prats, M.
In a process for producing shale oil from a subterranean oil-shale formation by controlled in situ combustion in a cavern that contains a mass of fracture-permeated oil shale, the oil shale is preheated with hot aqueous liquid to exfoliate the pieces of oil shale to cause a reduction in their particle size. This improves the distribution of permeabilities and surface area-to-volume ratios within the cavern prior to the initiation of underground combustion. (6 claims)
The Knox Project objective is to evaluate the potential of formations within the Cambrian-Ordovician strata above the Mt. Simon Sandstone (St. Peter Sandstone and Potosi Dolomite) as potential targets for carbon dioxide (CO2) sequestration in the Illinois and Michigan Basins. The suitability of the St. Peter Sandstone and Potosi Dolomite to serve as reservoirs for CO2 sequestration is discussed in separate reports. In this report the data gathered from the Knox project, the Illinois Basin – Decatur Project (IBDP) and Illinois Industrial Carbon Capture and Sequestration project (IL-ICCS) are used to make some conclusions about the suitability of the Maquoketa shale as a confining layer for CO2 sequestration. These conclusions are then upscaled to basin-wide inferences based on regional knowledge. Data and interpretations (stratigraphic, petrophysical, fractures, geochemical, risk, seismic) applicable to the Maquoketa Shale from the above mentioned projects was inventoried and summarized. Based on the analysis of these data and interpretations, the Maquoketa Shale is considered to be an effective caprock for a CO2 injection project in either the Potosi Dolomite or St. Peter Sandstone because it has a suitable thickness (~200ft. ~61m), advantageous petrophysical properties (low effective porosity and low permeability), favorable geomechanical properties, an absence of observable fractures and is regionally extensive. Because it is unlikely that CO2 would migrate upward through the Maquoketa Shale, CO2, impact to above lying fresh water aquifers is unlikely. Furthermore, the observations indicate that CO2 injected into the St. Peter Sandstone or Potosi Dolomite may never even migrate up into the Maquoketa Shale at a high enough concentrations or pressure to threaten the integrity of the caprock. Site specific conclusions were reached by unifying the data and conclusions from the IBDP, ICCS and the Knox projects. In the Illinois Basin, as one looks further away from
McMahon, P.B.; Böhlke, J.K.; Bruce, B.W.
Parts of the South Platte River alluvial aquifer in northeastern Colorado are underlain by the Pierre Shale, a marine deposit of Late Cretaceous age that is denitrification in the forms of organic carbon and sulfide minerals. Nested piezometers were sampled, pore water was squeezed from cores of shale, and an injection test was conducted to determine if denitrification in the shale was a sink for alluvial NO3/- and to measure denitrification rates in the shale. Measured values of NO3/-, N2, NH4/+, ??15[NO3/-], ??15N[N2], and ??15N[NH4/+] in the alluvial and shale pore water indicated that denitrification in the shale was a sink for alluvial NO3/-. Chemical gradients, reaction rate constants, and hydraulic head data indicated that denitrification in the shale was limited by the slow rate of NO3/- transport (possibly by diffusion) into the shale. The apparent in situ first-order rate constant for denitrification in the shale based on diffusion calculations was of the order of 0.04-0.4 yr-1, whereas the potential rate constant in the shale based on injection tests was of the order of 60 yr-1. Chemical data and mass balance calculations indicate that organic carbon was the primary electron donor for denitrification in the shale during the injection test, and ferrous iron was a minor electron donor in the process. Flux calculations for the conditions encountered at the site indicate that denitrification in the shale could remove only a small fraction of the annual agricultural NO3/- input to the alluvial aquifer. However, the relatively large potential first-order rate constant for denitrification in the shale indicated that the percentage of NO3/- uptake by the shale could be considerably larger in areas where NO3/- is transported more rapidly into the shale by advection.
Shales play a major role in the stability of slopes, both natural and engineered. This paper attempts to provide a review of the state-of-the-art in shale slope stability. The complexities of shale terminology and classification are first reviewed followed by a brief discussion of the important physical and mechanical properties of relevance to shale slope stability. The varied mechanisms of shale slope stability are outlined and their importance highlighted by reference to international shale slope failures. Stability analysis and modelling of anisotropic rock slope masses are briefly discussed and the potential role of brittle rock fracture and damage highlighted. A short review of shale slopes in open pits is presented.
Oxy desulfurization process and caustic treatment were applied in this work to remove sulfur from Jordanian oil shale. The oxy desulfurization process has been studied in a batch process using a high pressure autoclave, with constant stirring speed, and oxygen and water were used as desulfurizing reagents. Temperature, oxygen pressure, batch time, and particle size were found to be important process variables, while solid/liquid ratio was found to have no significant effect on the desulfurization process. The response of different types of oil shale to this process varied, and the effect of the process variables on the removal of total sulfur, pyritic sulfur, organic sulfur, total carbon, and organic carbon were studied. An optimum condition for oxy desulfurization of El-Lajjun oil shale, which gave maximum sulfur removal with low loss of carbon, was determined from the results of this work. The continuous reaction model was found to be valid, and the rate of oxidation for El-Lajjun oil shale was of the first order with respect to total sulfur, organic sulfur, total carbon, and organic carbon. For pyritic sulfur oxidation, the shrinking core model was found to hold and the rate of reaction controlled by diffusion through product ash layer. An activation energy of total sulfur, organic sulfur, pyritic sulfur, total carbon, and organic carbon oxidation was calculated for the temperature range of 130 -190 degrees celsius. In caustic treatment process, aqueous sodium hydroxide at 160 degrees celsius was used to remove the sulfur from El-Lajjun oil shale. The variables tested (sodium hydroxide concentration and treatment time) were found to have a significant effect. The carbon losses in this process were less than in the oxy desulfurization process. 51 refs., 64 figs., 121 tabs. (A.M.H.)
Roshan, H; Al-Yaseri, A Z; Sarmadivaleh, M; Iglauer, S
The low recovery of hydraulic fracturing fluid in unconventional shale reservoirs has been in the centre of attention from both technical and environmental perspectives in the last decade. One explanation for the loss of hydraulic fracturing fluid is fluid uptake by the shale matrix; where capillarity is the dominant process controlling this uptake. Detailed understanding of the rock wettability is thus an essential step in analysis of loss of the hydraulic fracturing fluid in shale reservoirs, especially at reservoir conditions. We therefore performed a suit of contact angle measurements on a shale sample with oil and aqueous ionic solutions, and tested the influence of different ion types (NaCl, KCl, MgCl2, CaCl2), concentrations (0.1, 0.5 and 1M), pressures (0.1, 10 and 20MPa) and temperatures (35 and 70°C). Furthermore, a physical model was developed based on the diffuse double layer theory to provide a framework for the observed experimental data. Our results show that the water contact angle for bivalent ions is larger than for monovalent ions; and that the contact angle (of both oil and different aqueous ionic solutions) increases with increase in pressure and/or temperature; these increases are more pronounced at higher ionic concentrations. Finally, the developed model correctly predicted the influence of each tested variable on contact angle. Knowing contact angle and therefore wettability, the contribution of the capillary process in terms of water uptake into shale rocks and the possible impairment of hydrocarbon production due to such uptake can be quantified. PMID:27156090
In Estonia, electricity production mainly takes place in two oil-shale-fired power plants. The combustion of oil shale leads to the release of radionuclides in the atmosphere. In the present study the partitioning and the balance of natural radionuclides in oil shale combustion is highlighted. The values are given of activity concentrations of the radionuclides in oil shale and in oil shale ashes, of enrichment factors for different oil shale ash fractions, of ash/fuel radioactivity ratios for the individual radionuclides, and of the total radioactivity of ashes and atmospheric discharges per GW of produced electric energy. (A.K.)
Clerici, A.; Alimonti, G.
In recent years there has been a world "revolution" in the field of unconventional hydrocarbon reserves, which goes by the name of "shale gas", gas contained inside clay sediments micropores. Shale gas finds particular development in the United States, which are now independent of imports and see a price reduction to less than one third of that in Europe. With the high oil prices, in addition to the non-conventional gas also "oil shales" (fine-grained sedimentary rocks that contain a large amount of organic material to be used both to be directly burned or to extract liquid fuels which go under the name of shale oil), extra heavy oils and bitumen are becoming an industrial reality. Both unconventional gas and oil reserves far exceed in the world the conventional oil and gas reserves, subverting the theory of fossil fuels scarcity. Values and location of these new fossil reserves in different countries and their production by comparison with conventional resources are presented. In view of the clear advantages of unconventional fossil resources, the potential environmental risks associated with their extraction and processing are also highlighted.
The overall objective is to develop a new technology for manufacturing valuable marketable products form shale oil. Phase-I objectives are to identify desirable components in shale oil, develop separations techniques for those components, identify market needs and to identify plausible products manufacturable from raw shale oil to meet those needs. Another objective is to conduct preliminary process modeling and economic analysis of selected process sequences and product slates, including an estimation of process, costs and profitability. The end objective of Phase-I is to propose technically and economically attractive separations and conversion processes for small-scale piloting in the optional Phase-II. Optional Phase-II activities include the pilot-scale test of the Shale Oil Native Products Extraction (SO-NPX) technology and to produce specification products. Specific objectives are to develop the engineering data on separations processing, particularly those in which mixtures behave non-ideally, and to develop the conversion processes for finishing the separations concentrates into specification products.The desired process scenarios will be developed and economic analysis will be performed on the process scenarios. As a result of the process simulation and economic analysis tasks, a product manufacture and test marketing program shall be recommended for the optional Phase-III. Optional Phase-III activities are to manufacture specification products and to test market those products in order to ensure market acceptability. The activities involve the assembling of the technical, market and economic data needed for venture evaluation. The end objective is to develop the private sector interest to carry this technology forward toward commercialization.
James W. Bunger
Raw kerogen oil is rich in heteroatom-containing compounds. Heteroatoms, N, S & O, are undesirable as components of a refinery feedstock, but are the basis for product value in agrochemicals, pharmaceuticals, surfactants, solvents, polymers, and a host of industrial materials. An economically viable, technologically feasible process scheme was developed in this research that promises to enhance the economics of oil shale development, both in the US and elsewhere in the world, in particular Estonia. Products will compete in existing markets for products now manufactured by costly synthesis routes. A premium petroleum refinery feedstock is also produced. The technology is now ready for pilot plant engineering studies and is likely to play an important role in developing a US oil shale industry.
Two points of view about shale gas exploitation are presented. The first one is proposed by an American scientist who outlines that the consequences of shale gas exploitation in the USA are already disastrous, notably in terms of water consumption by hydraulic fracturing (50 to 100 times more water for shale gas than for oil or natural gas), of greenhouse gas emissions (a lot a methane is leaking during this exploitation, and methane has a much stronger greenhouse effect than CO2), of environmental risks (shale gas wells are significantly susceptible to pollute underground waters, and radon is present in shale gas and would be released in housing). The second point of view outlines the lack of knowledge of the French underground, and that it is therefore impossible to assess shale gas reserves and exploitation possibilities
Odusina, Elijah; Sondergeld, Carl; Rai, Chandra [University of Oklahoma (United States)
In recent years, the importance of shales as unconventional gas resources has grown significantly. It is therefore important to reach a better understanding of their petrophysical properties. One of the important rock properties that is directly linked to successful hydrocarbon recovery is wettability. This paper presents a study on shale wettability using nuclear magnetic resonance (NMR) to monitor sequential imbibition of brine and oil. Due to the presence of mineralogical variations, low permeability and viscosity, and complex pore structure, the interpretation of wettability using conventional approaches becomes complex. Samples that included 21 core plugs from the Eagle Ford shale, 12 from the Barnett, 11 from the Floyd, and 10 from the Woodford shale were analyzed. The NMR study confirmed the water-wet behavior of Berea sandstone. From the study, it was seen that the Woodford shale showed more affinity for dodecane than did the other shales.
This paper offers insights into the role for regional science and regional scientists in analyzing shale-energy development. The stories described are drawn from popular press accounts of the Bakken Basin in North Dakota and the dry-gas-producing counties of the Marcellus Shale in Northern and Central Pennsylvania. The comparison of the two shale plays highlights housing, labor market, and fiscal issues for these two locations.
Mbia, Ernest Ncha; Fabricius, Ida Lykke; Frykman, Peter;
strain data. We found that Kozeny's modelled permeability fall in the same order of magnitude with measured permeability for shale rich in kaolinite but overestimates permeability by two to three orders of magnitudes for shale with high content of smectite. The empirical Yang and Aplin model gives good...... permeability estimate comparable to the measured one for shale rich in smectite. This is probably because Yang and Aplin model was calibrated in London clay which is rich in smectite....
Results of previous research about the mineralogical composition of Estonian oil shale ash focused on using X-ray diffractometry, problems related to oil shale combustion, and utilization of oil shale ashes were analysed. (author)
This bibliographical sheet presents a book which aims at informing citizen about the irreversible consequences of shale gas exploitation on the environment, and about the economical and social aspects of an exploitation of this energy on a large scale. The author highlights the technical and environmental problems raised by hydraulic fracturing, outlines the complexity of the regulatory, legal and administrative framework, discusses the arguments which support shale gas exploitation, and outlines the importance of and energy transition without shale gas. The author notably outlines the conflicts of interest which pervert the debate on shale gas, notably within the French National Assembly
Stevens, P; Simons, S; De Silva, P. N. K.
The world is increasingly taking interest in the potential for a shale gas revolution. Australia is no exception to this trend. The key question for Federal, State and local governments is, assuming a shale gas revolution is seen as desirable, what policy measures may be taken in order to achieve this end and what should any debate over shale gas policy be focusing on? This brief paper sets the context for any shale gas revolution. It then outlines the characteristics present in the US that w...
Johnson, Mike; Davidson, Jim; Mortensen, Paul
In a relatively new development over just the past few years, shale formations are being targeted for natural gas production. Based on initial results, there may be significant potential for shale gas in various regions of Canada, not only in traditional areas of conventional production but also non-traditional areas. However, there is much uncertainty because most Canadian shale gas production is currently in experimental or early developmental stages. Thus, its full potential will not be known for some time. If exploitation proves to be successful, Canadian shale gas may partially offset projected long-term declines in Canadian conventional natural gas production.
This report contains a compilation of much of the data needed for evaluating the thermal properties of clays and shales. The data on shales are limited so much of the review is concerned with clays and ceramic products. The information presented should allow a preliminary evaluation of the problems that will arise when canisters containing high-activity wastes are buried in shales. A computer library search was conducted and most of the data specific to the thermal properties of shales was probably found. Much more data are available on density, porosity, ceramic properties, diagenesis, etc., but the main points have been summarized
Sica, Carlo E.
Shale gas has become one of Pennsylvania's major resources in recent years and the gas boom has proceeded in spite of uncertainty over the environmental risks of its production process. This thesis argues that location alone cannot explain why shale gas boomed in Pennsylvania. Using interviews with corporate and state executives, I argue that the scalar dimensions of the neoliberal environmental governance of shale gas were critical to understanding why shale gas boomed in Pennsylvania. These actors supported the preemption of local scales of governance by the state as a scalar fix for capital accumulation from shale gas development. They also legitimated the scalar fix by assembling a neat stack of scale frames that made shale gas seem to benefit everyone. These scale frames made shale gas appear as if it would provide local employment, regional supplies of cheap gas, national energy security, abundant gas for tight global markets, and a mitigating strategy for global climate change. In arguing this point, I present a history of how shale gas became a resource that outlines the critical role of the state in that process.
Two of the primary energy sources most dited as alternatives to the traditional fossil fuels are oil shales and nuclear energy. Several proposed processes for the extraction and utilization of oil and gas from shale are given. Possible efficient ways in which nuclear heat may be used in these processes are discussed
The experimental work discussed in this report is part of an ongoing program concerning evaluation of sedimentary and other rock types as potential hosts for a geologic repository. The objectives are the development of tools and techniques for repository characterization and performance assessment in a diversity of geohydrologic settings. This phase of the program is a laboratory study that investigates fundamental thermomechanical properties of several different shales. Laboratory experiments are intrinsically related to numerical modeling and in situ field experiments, which together will be used for performance assessment
Hansen, F.D.; Vogt, T.J.
The experimental work discussed in this report is part of an ongoing program concerning evaluation of sedimentary and other rock types as potential hosts for a geologic repository. The objectives are the development of tools and techniques for repository characterization and performance assessment in a diversity of geohydrologic settings. This phase of the program is a laboratory study that investigates fundamental thermomechanical properties of several different shales. Laboratory experiments are intrinsically related to numerical modeling and in situ field experiments, which together will be used for performance assessment.
Michael D. Burnaman; Wenwu Xia; John Shelton
The uniqueness of shale gas plays is contrasted with conventional oil and gas exploration. Based on our ten year history in shale gas exploration, a practical 17 point list of criteria to use for screening shale gas projects and ranking that encompasses geoscience, geochemistry, reservoir engineering, drilling, completions and production operations is developed and explained. Other considerations that will impact shale gas development are identified and discussed. Some key methodologies to incorporate in the evaluation process are also proposed. The outcome of this proposed screening process, if rigorously applied,should quickly identify the projects that have the most likely chance for success for recommendation to management. Examples from active shale gas plays in the United States are used to support these criteria and references to relevant recent publications and presentations are provided.
Douglas, Craig C.
Shale gas represents a major fraction of the proven reserves of natural gas in the United States and a collection of other countries. Higher gas prices and the need for cleaner fuels provides motivation for commercializing shale gas deposits even though the cost is substantially higher than traditional gas deposits. Recent advances in horizontal drilling and multistage hydraulic fracturing, which dramatically lower costs of developing shale gas fields, are key to renewed interest in shale gas deposits. Hydraulically induced fractures are quite complex in shale gas reservoirs. Massive, multistage, multiple cluster treatments lead to fractures that interact with existing fractures (whether natural or induced earlier). A dynamic approach to the fracturing process so that the resulting network of reservoirs is known during the drilling and fracturing process is economically enticing. The process needs to be automatic and done in faster than real-time in order to be useful to the drilling crews.
Park W. C.
Full Text Available Oil shale deposits vary significantly in their geological nature and can represent enormous reserves of low grades ores for various minerals such as alumina, sodium carbonates, molybdenum, nickel, vanadium, and uranium. The treatment of these rocks for mineral values can be economically attractive when coupled with the production of synthetic oil. Mutually shared costs for extractinq the mineral values can be favorably affected by utilizing by-products from the oil shale retorting. These can include the residual char for a carbonaceous reductant or fuel, C02 for acidification, or lime and soda ash for caustic. Conversely, an inappropriate choice of oil shale retorting conditions can substantially lower subsequent recovery of mineral values from the spent shale. The proceeding considerations will be discussed for several oil shale deposits including: 1. The Green River formation in the mid-western United States which is not only oil rich but also represents a nearly inexhaustible domestic supply of alumina and sodium carbonates and 2. The block shale of Julia Creek, Queensland, Australia, the Devonian Chattanooga shale in the United States, the Cambrian Kulm shale in Sweden, the Permian Lodeve shale in southern France, and the Paleozoic shales from Korea and USSR for energy and metal values such as molybdenum, nickel, vanadium, and uranium. La nature géologique des dépôts de schistes à huile est très variée ; ces schistes peuvent représenter des réserves énormes de minerais à faible teneur de métaux tels que l'aluminium, le molybdène, le nickel, le vanadium, l'uranium, sans oublier le carbonate de sodium. Le traitement de ces roches pour leur valeur minérale peut être attractif économiquement s'il est associé à la production d'huile synthétique. La répartition des coûts d'extraction des métaux peut être favorablement affectée en utilisant les sous-produits du traitement des schistes à huile. Ceci peut comprendre le goudron
Under the present conditions of limited demand for oil shale, the Estonian oil shale mining industry is in a state of over capacity. This results in an inefficient use of labor. This working atmosphere has resulted in high production costs per tonne of mined oil shale. To improve economic factors, it is necessary to concentrate production into a limited number of mines working at full capacity and to modernize the mining technology at those mines. A development plan for oil shale mining is proposed. It primarily includes modernization of the prospective mines to be kept in operation and reduction of surface mining at the Sirgala and Narva open cast pits. This will result in conservation of oil shale reserves for 8- 10 years of future production. It is recommended that the resumption of mining in these fields be by underground means. The detailed plan does not call for the untimely closing of mines before the exhaustion of their reserves of oil shale. At the same time, a relatively stable level of mining activity (10-13 million tonnes per year) with minimal investments in the oil shale industry is guaranteed until 2025. (author)
Shale formations have been suggested as a potential site for a high level nuclear waste repository. As a first step in the study of the possible interaction of nuclides with the organic components of the shales, literature on the identification of organic compounds from various shales of the continent of the United States has been reviewed. The Green River shale of the Cenozoic era is the most studied shale followed by the Pierre shale of the Mesozoic era and the Devonian black shale of the Paleozoic era. Organic compounds that have been identified from these shales are hydrocarbons, fatty acids, fatty alcohols, steranes, terpanes, carotenes, carbohydrates, amino acids, and porphyrins. However, these organic compounds constitute only a small fraction of the organics in shales and the majority of the organic compounds in shales are still unidentified
Smith, N.; Turner, P.; Williams, G.
Organic-rich shale contains significant amounts of gas held within fractures and micropores and adsorbed onto organic matter. In the USA shale gas extracted from regionally extensive units such as the Barnett Shale currently accounts for 6% of gas production and is likely to reach 30% by 2015. Shale gas prospectivity is controlled by the amount and type of organic matter held in the shale, its thermal maturity, burial history, microporosity and fracture spacing and orientation. Potential targ...
This bibliographical sheet presents a book which addresses the issue of shale gas. A first part describes the origin of this gaseous hydrocarbon, the composition of shale gas and its extraction, the technique of hydraulic fracturing, and the environmental risks. A second part addresses the economic, ecologic and political issues. The authors outline that all signs are there to prove the alarming hazards of shale gas. One of the authors outlines the necessity of an energy transition, far from fossil and nuclear energy, in order to guarantee a high level of protection of human health and of the environment
Yiwen Ju; Guochang Wang; Hongling Bu; Qingguang Li; Zhifeng Yan
The depositional environment of organic-rich shale and the related tectonic evolution in China are rather different from those in North America. In China, organic-rich shale is not only deposited in marine environment, but also in non-marine environment: marine-continental transitional environment and lacustrine environment. Through analyzing large amount of outcrops and well cores, the geologic features of organic-rich shale, including mineral composition, organic matter richness and type, a...
Highlights: • We developed a hybrid LCI model to calculate the shale-to-well energy and emissions of shale gas production in China. • The process model is based on the first horizontal well in China, and IO model uses 2007 economy benchmark data. • The shale-to-well energy was calculated to be 59 TJ, 42% of product chain use and 58% of on-site consumption. • The shale-to-well GHG emissions were 5500 metric tons of CO2e. • The onsite water consumption of well construction was 25,000 m3, and was dominated by fracturing water use, about 95%. - Abstract: Tapping its large reserves of unconventional gas, China has launched shale gas exploration and started drilling wells in trial development zones. To better understand the potential energy and air pollution implications of shale gas production in China, this study developed a hybrid life cycle inventory (LCI) model that combines process and input–output (IO) based LCI methods for estimating “shale-to-well” energy use, resource use, and emissions of air pollutants. The model’s structure and inputs are based on data from the first shale gas horizontal well in China. The IO model was constructed using the 2007 benchmark IO table for China. Results suggest shale-to-well energy use of 59 TJ and shale-to-well greenhouse gas (GHG) emissions of 5500 metric tons of carbon dioxide equivalents (CO2e). Shale-to-well energy use and air emissions were dominated by the production and use of diesel fuel for oil-based drilling fluids and for on-site combustion, and by fugitive emissions and flaring from well completion. The results shed light on some potential energy and air pollutant emission impacts of a shift from coal to shale gas in China, and highlight opportunities for reducing these impacts moving forward
In march 2010 three authorizations to search for shale gases were delivered in France in the regions of Montelimar, Nant and Villeneuve-de-Berg. A general public outcry has led the government to freeze the projects till a complete assessment of the impact on the environment is made. The fears of the public are based on the feedback experience in the Usa where some underground waters were polluted. The source of pollution is twofold: first the additives used in the injected fluids (methanol as an anti-microbic agent, hydrochloric acid to dissolve natural cements or glycol ethylene as a deposit inhibitor) and secondly metal particles of copper, zinc or lead trapped in the clay layers and released by the injection of the fluids. It appears also that the injection of high pressure fluids near a crack can induce earth tremors by reactivating the crack. (A.C.)
The distribution of fractured organic shale basins in the United States was discussed. More than 20,000 gas shale wells have been drilled in the Appalachian Basin which produce about 960 MMscf/D from fractured organic shales. The key features of organic-rich shale reservoirs were described. These reservoirs contain significant amounts of gas in place, as well as sorbed gas in the black organic shale matrix. When natural fractures are present in these formations, such as in the Antrim Shale in northern Michigan, there exists significant production potential. A review of the production history of the Antrim Shale was provided. The storage and production techniques which determine the performance of these formations were described and the procedures to evaluate the techniques were summarized. The impact of technology and development on the production of the Antrim Shale was also reviewed. Evaluation of these shale resources is made through the estimation of reserves by analyzing short-term and long-term production data. Reservoir pressure and effective bottom hole flowing pressure can also be used to evaluate the reserves. tabs., figs
Mbia, Ernest Ncha; Fabricius, Ida Lykke; Krogsbøll, Anette
Permeability is often very difficult to measure or predict in shale lithology. In this work we are determining shale permeability from consolidation tests data using Wissa et al., (1971) approach and comparing the results with predicted permeability from Kozeny’s model. Core and cuttings materials...... were obtained from Fjerritslev shale Formation in Juassic interval of Stenlille and Vedsted on-shore wells of Danish basin. The calculated permeability from specific surface and porosity vary from 0.09 to 48.53 μD while that calculated from consolidation tests data vary from 1000 μD at a low vertical...... effective stress to 9 μD at high vertical effective stress of 100 MPa. The indirect permeability calculated from consolidation tests falls in the same magnitude at higher vertical effective stress, above 40 MPa, as that of the Kozeny model for shale samples with high non-clay content ≥ 70% but are higher by...
Rupieper, A. [Linde Engineering Dresden GmbH, Dresden (Germany)
US shale gas reserves with more than 860 TCF (Source: U.S. Energy Information Administration study World Shale Gas Resources) account for 2 of the global largest reserves after China. In 7 areas of the US, these reserves are systematically explored, providing a significant amount of cheap natural gas source for decades. The ethane share, carried by such shale gas, can reach up to 16%. Ethane has been already in the past 2 most important feedstock for Steamcrackers, being the backbone of the Petrochemical Industry. Due to availability of vast shale gas, the US steamcracker industry is facing a shift from naphtha to shale gas ethane, as the margin of Ethylene produced from shale gas ethane is significantly larger than that of naphtha based Ethylene (app. + 630 USD/t Ethylene). As a consequence shale gas is ''the magic bullet'' incinerating investments into Steamcrackers and downstream plants for U.S petrochemical industry. Steamcracker Projects with an additional ethylene production capacity of more than 17 million tons/a by 2020 are announced or already under construction. Investments into downstream plants refining the C2 derivatives will follow or are already in planning/engineering phase. But the US market cannot absorb all related products, causing a significant export exposure, which will influence global trade flows for C2 derivatives and affect prices. This article presents the impact of shale gas ethane cracking on: - Trade flow of C2 derivatives; - By-product deficits; - Alternate C3+ derivative production routes; - Challenges related to engineering requirements and project execution for Steamcracker projects. (orig.)
Campbell, R. A.; Hudgins, J. L.; Morris, P. W.; Reid, H., Jr.; Zimmerman, J. E. (Inventor)
A coal-shale interface detection system for use with coal cutting equipment consists of a reciprocating hammer on which an accelerometer is mounted to measure the impact of the hammer as it penetrates the ceiling or floor surface of a mine. A pair of reflectometers simultaneously view the same surface. The outputs of the accelerometer and reflectometers are detected and jointly registered to determine when an interface between coal and shale is being cut through.
Ovidiu – Horia Maican
Some countries with large reserves intend to promote shale gas production, in order to reduce their dependency on imported gas. Shale gas will be an important new aspect in the world energy scene, with many effects. European Union wants secure and affordable sources of energy. Natural gas is the cleanest fossil fuel and a vital component of European Union's energy strategy. One of the most important aspects is that gas produces significantly cleaner energy than other fossil fuels. From a lega...
Gaines, Robert R.; Hammarlund, Emma U.; Hou, Xianguang; Qi, Changshi; Gabbott, Sarah E.; Zhao, Yuanlong; Peng, Jin; Canfield, Donald E.
Exceptionally preserved fossil biotas of the Burgess Shale and a handful of other similar Cambrian deposits provide rare but critical insights into the early diversification of animals. The extraordinary preservation of labile tissues in these geographically widespread but temporally restricted soft-bodied fossil assemblages has remained enigmatic since Walcott’s initial discovery in 1909. Here, we demonstrate the mechanism of Burgess Shale-type preservation using sedimentologic and geochemic...
The studies reported herein are intended to provide more certainty regarding estimates of the costs of controlling environmental residuals from oil shale technologies being readied for commercial application. The need for this study was evident from earlier work conducted by the Office of Environment for the Department of Energy Oil Shale Commercialization Planning, Environmental Readiness Assessment in mid-1978. At that time there was little reliable information on the costs for controlling residuals and for safe handling of wastes from oil shale processes. The uncertainties in estimating costs of complying with yet-to-be-defined environmental standards and regulations for oil shale facilities are a critical element that will affect the decision on proceeding with shale oil production. Until the regulatory requirements are fully clarified and processes and controls are investigated and tested in units of larger size, it will not be possible to provide definitive answers to the cost question. Thus, the objective of this work was to establish ranges of possible control costs per barrel of shale oil produced, reflecting various regulatory, technical, and financing assumptions. Two separate reports make up the bulk of this document. One report, prepared by the Denver Research Institute, is a relatively rigorous engineering treatment of the subject, based on regulatory assumptions and technical judgements as to best available control technologies and practices. The other report examines the incremental cost effect of more conservative technical and financing alternatives. An overview section is included that synthesizes the products of the separate studies and addresses two variations to the assumptions.
Gaines, Robert R; Hammarlund, Emma U; Hou, Xianguang; Qi, Changshi; Gabbott, Sarah E; Zhao, Yuanlong; Peng, Jin; Canfield, Donald E
Exceptionally preserved fossil biotas of the Burgess Shale and a handful of other similar Cambrian deposits provide rare but critical insights into the early diversification of animals. The extraordinary preservation of labile tissues in these geographically widespread but temporally restricted soft-bodied fossil assemblages has remained enigmatic since Walcott's initial discovery in 1909. Here, we demonstrate the mechanism of Burgess Shale-type preservation using sedimentologic and geochemical data from the Chengjiang, Burgess Shale, and five other principal Burgess Shale-type deposits. Sulfur isotope evidence from sedimentary pyrites reveals that the exquisite fossilization of organic remains as carbonaceous compressions resulted from early inhibition of microbial activity in the sediments by means of oxidant deprivation. Low sulfate concentrations in the global ocean and low-oxygen bottom water conditions at the sites of deposition resulted in reduced oxidant availability. Subsequently, rapid entombment of fossils in fine-grained sediments and early sealing of sediments by pervasive carbonate cements at bed tops restricted oxidant flux into the sediments. A permeability barrier, provided by bed-capping cements that were emplaced at the seafloor, is a feature that is shared among Burgess Shale-type deposits, and resulted from the unusually high alkalinity of Cambrian oceans. Thus, Burgess Shale-type preservation of soft-bodied fossil assemblages worldwide was promoted by unique aspects of early Paleozoic seawater chemistry that strongly impacted sediment diagenesis, providing a fundamentally unique record of the immediate aftermath of the "Cambrian explosion." PMID:22392974
Progress in the exploitation of shale oil and shale gas in the USA over the last three years has been spectacular, with the result that these terms are frequently used by the media in France and Europe. To clarify the debate, it seemed to us to be indispensable to go back to the fundamentals of these notions: those of geology. (authors)
Gasification of oil shales followed by catalytic reforming can yield synthetic gas, which is easily transportable and may be used as a heat source or for producing liquid fuels. The aim of the present work was to study the gasification of oil shales by solar radiation, as a mean of combining these two energy resources. Such a combination results in maximizing the extractable fuel from the shale, as well as enabling us to store solar energy in a chemical bond. In this research special attention was focused upon the question of the possible enhancement of the gasification by direct solar irradiation of the solid carbonaceous feed stock. The oil shale served here as a model feedstock foe other resources such as coal, heavy fuels or biomass all of which can be gasified in the same manner. The experiments were performed at the Weizman institute's solar central receiver, using solar concentrated flux as an energy source for the gasification. The original contributions of this work are : 1) Experimental evidence is presented that concentrated sunlight can be used effectively to carry out highly endothermic chemical reactions in solid particles, which in turn forms an essential element in the open-loop solar chemical heat pipe; 2) The solar-driven gasification of oil shales can be executed with good conversion efficiencies, as well as high synthesis gas yields; 3)There was found substantial increase in deliverable energy compared to the conventional retorting of oil shales, and considerable reduction in the resulting spent shale. 5) A detailed computer model that incorporates all the principal optical and thermal components of the solar concentrator and the chemical reactor has been developed and compared favorably against experimental data. (author)
Eugster, Hans P.
The relationships between oil shales, evaporites and sedimentary ore deposits can be classified in terms of stratigraphic and geochemical coherence. Oil shale and black shale deposition commonly follows continental red beds and is in turn followed by evaporite deposition. This transgressive-regressive sequence represents an orderly succession of depositional environments in space and time and results in stratigraphic coherence. The amount of organic carbon of a sediment depends on productivity and preservation, both of which are enhanced by saline environments. Work on Great Salt Lake. Utah, allows us to estimate that only 5% of TOC originally deposited is preserved. Inorganic carbonate production is similar to TOC production, but preservation is much higher. Oil shales and black shales commonly are enriched in heavy metals through scavenging by biogenic particles and complexation by organic matter. Ore deposits are formed from such rocks through secondary enrichment processes, establishing a geochemical coherence between oil shales and ore deposits. The Permian Kupferschiefer of N. Europe is used as an example to define a Kupferschiefer type (KST) deposit. Here oxygenated brines in contact with red beds become acidified through mineral precipitation and acquire metals by dissolving oxide coatings. Oxidation of the black shale leads to further acid production and metal acquisition and eventually to sulfide deposition along a reducing front. In order to form ore bodies, the stratigraphic coherence of the red bed-black shale-evaporite succession must be joined by the geochemical coherence of the ore body-evaporite-black shale association. The Cretaceous Cu-Zn deposits of Angola, the Zambian Copperbelt as well as the Creta, Oklahoma, deposits are other KST examples. In the Zambian Copperbelt, evaporites are indicated by the carbonate lenticles thought to be pseudomorphs after gypsum-anhydrite nodules. MVT deposits are also deposited by acid brines, but at more
The method of semi-coking oil shale in the circular retorting chamber makes it possible to ensure a more uniform distribution of the heat carriers gas across the shale bed, than in the vertically placed retorting chambers with cross-current heat carrier flow, and in the generators using the counter-current method of heat exchange. This also ensures the most favourable conditions for effective heat transfer in the retorting chamber from the gas flow to the shale bed due to the following factors: absence of the lateral outer walls in the retorting chamber; the concentrical arrangement of the retorting chamber and the passage of the gaseous heat carrier through the shale bed from the periphery of the retort to its center; the bulk of the oil shale charged passes through the hot part of the retorting chamber (i.e. on the side of inlet of the gaseous heat carrier into the shale bed). As a result, processing the oil shale in the generators with circular retorting chambers leads to a decrease in the temperature of oil vapours at the gas outlet on an average from 220 to 150o C and the reduction of the specific air consumption for the process - from 360 to 250 m3/t. According to the calculated data, it ensures an increase in oil yield from 78 to 84% of the Fischer assay oil. The application of the circular retorting chamber in the generators, creates conditions for increased unit throughput rates of the retorts 1.5-2.0 times with a simultaneous increase in the oil yield. For processing oil shales rich in organic material, which readily bitumenize, retorts for a throughput of 1500 tonnes per day have been developed and are already under construction at the P O 'Slantsekhim'. Project designs for the leaner shales can be developed for throughput rates in excess of 5000-6000 tonnes per day. The retorts will have a comparatively small diameter and a simpler design than the 1000 t/day generators being now in operation. (author). 14 refs., 2 tabs., fig
U.S. Geological Survey, Department of the Interior — This database contains Oil Shale Assays, Borehole Locations and Formation Tops that were used in support of the 2009 Oil Shale Assessment (Survey Fact Sheet...
Tucker, Yael Tarlovsky; Kotcon, James; Mroz, Thomas
Marcellus Shale occurs at depths of 1.5-2.5 km (5000 to 8000 feet) where most geologists generally assume that thermogenic processes are the only source of natural gas. However, methanogens in produced fluids and isotopic signatures of biogenic methane in this deep shale have recently been discovered. This study explores whether those methanogens are indigenous to the shale or are introduced during drilling and hydraulic fracturing. DNA was extracted from Marcellus Shale core samples, preinjected fluids, and produced fluids and was analyzed using Miseq sequencing of 16s rRNA genes. Methanogens present in shale cores were similar to methanogens in produced fluids. No methanogens were detected in injected fluids, suggesting that this is an unlikely source and that they may be native to the shale itself. Bench-top methane production tests of shale core and produced fluids suggest that these organisms are alive and active under simulated reservoir conditions. Growth conditions designed to simulate the hydrofracture processes indicated somewhat increased methane production; however, fluids alone produced relatively little methane. Together, these results suggest that some biogenic methane may be produced in these wells and that hydrofracture fluids currently used to stimulate gas recovery could stimulate methanogens and their rate of producing methane. PMID:25924080
UK shale gas exploitation currently at a very early stage. Potentially significant quantities but resources are not yet proven. In the UK a number of the potentially exploitable shales are below important aquifers.Water demand for shale gas production may not be significant relative to other uses but local needs must be considered carefully. Shale gas extraction will use/mobilise potential pollutants. Risks must be fully assessed and managed effectively – through to post abandonment. The most...
D. P. Gerish
Full Text Available This article describes the main aspects of shale gas production, its origin and properties. The particular issues related to the shale gas production, as well as the public and official attitude to the perspectives of its usage in Russian Federation are analyzed. The general problems of the shale gas exploration and production in the Russian Federation are discussed. The current and prognostic rates of shale gas production in USA are shown.
D. P. Gerish; O. E. Kochneva
This article describes the main aspects of shale gas production, its origin and properties. The particular issues related to the shale gas production, as well as the public and official attitude to the perspectives of its usage in Russian Federation are analyzed. The general problems of the shale gas exploration and production in the Russian Federation are discussed. The current and prognostic rates of shale gas production in USA are shown.
Robert W. Gilmer; Emily Kerr
The Texas experiment in extracting natural gas from the Barnett Shale proved the technical feasibility of shale gas development and brought costs within bounds that promise to give shale gas an important role in global energy supplies for decades to come. ; Shale gas cost estimates vary widely, partly because of limited experience in a few basins and partly because the technology is evolving. Prices of competing energy sources at levels seen today will likely stimulate continued rapid develop...
Over the past decade, the rapid increase in shale gas and shale oil production in the United States has profoundly changed energy markets in North America, and has led to a significant decrease in American natural gas prices. The possible existence of large shale deposits in Europe, mainly in France, Poland and the United Kingdom, has fostered speculation on whether the "shale revolution", and its accompanying macroeconomic impacts, could be duplicated in Europe. However, a number of uncertai...
Bernard, Sylvain; Horsfield, Brian
Shale gas systems serve as sources, reservoirs, and seals for unconventional natural gas accumulations. These reservoirs bring numerous challenges to geologists and petroleum engineers in reservoir characterization, most notably because of their heterogeneous character due to depositional and diagenetic processes but also because of their constituent rocks' fine-grained nature and small pore size -- much smaller than in conventional sandstone and carbonate reservoirs. Significant advances have recently been achieved in unraveling the gaseous hydrocarbon generation and retention processes that occur within these complex systems. In addition, cutting-edge characterization technologies have allowed precise documentation of the spatial variability in chemistry and structure of thermally mature organic-rich shales at the submicrometer scale, revealing the presence of geochemical heterogeneities within overmature gas shale samples and, notably, the presence of nanoporous pyrobitumen. Such research advances will undoubtedly lead to improved performance, producibility, and modeling of such strategic resources at the reservoir scale.
Significant advancements in the experimental analysis of soils and shales have been achieved during the last few decades. Outstanding progress in the field has led to the theoretical development of geomechanical theories and important engineering applications. This book provides the reader with an overview of recent advances in a variety of advanced experimental techniques and results for the analysis of the behaviour of geomaterials under multiphysical testing conditions. Modern trends in experimental geomechanics for soils and shales are discussed, including testing materials in variably saturated conditions, non-isothermal experiments, micro-scale investigations and image analysis techniques. Six theme papers from leading researchers in experimental geomechanics are also included. This book is intended for postgraduate students, researchers and practitioners in fields where multiphysical testing of soils and shales plays a fundamental role, such as unsaturated soil and rock mechanics, petroleum engineering...
Full Text Available The article investigates the questions of thermocatalytical conversion of organic mass of coal (OMC, it is shown that in the absence of a catalyst process is carried out by a radical process. Accumulated data on the properties for radicals of different structure and therefore different reaction capacity enables us to understand and interpret the conversion of OMC. Thermal conversion of OMC regarded as a kind of depolymerization, accompanied by decomposition of the functional groups with the formation of radicals, competing for hydrogen atom. Catalyst can change the direction and conditions of the process. Modern catalysts can reduce the process pressure up to 50 atm., with a high degree of coal conversion. We consider examples of simultaneous conversion of coal and shale, shale and masut, shale and tar.
Young, D.K.; Shih, S.; Yen, T.F.
Bioleaching of Green River oil shale by acid-producing autotrophic sulfur bacteria was simulated by dilute acid treatment. In this manner about 40 percent weight loss (dolomite and calcite) was achieved. This acid treated oil shale sample was stepwise oxidized (ca. 30 cycles) in a mild alkaline permagnate solution for the removal of kerogen. The acids recovered from the oxidation were converted to methyl esters and subsequently analyzed by gas chromatography and NMR spectroscopy. For comparison, products derived from other oxidative means (air, hydrogen peroxides, ozone, etc.) are discussed. Aside from the elucidation of the kerogen structure, the objective of the study was to achieve an economic process for the recovery of useful chemicals from oil shale kerogen.
Advances in drilling and extraction of natural gas have resulted in rapid expansion of wells in shale basins. The rate of gas well installation in the Fayetteville shale is 774 wells a year since 2005 with thousands more planned. The Fayetteville shale covers 23,000 km2 although ...
Shale gas is viewed by many as a global energy game-changer. However, serious concerns exist that shale gas generates more greenhouse gas emissions than does coal. In this work the related published data are reviewed and a reassessment is made. It is shown that the greenhouse gas effect of shale gas is less than that of coal over long term if the higher power generation efficiency of shale gas is taken into account. In short term, the greenhouse gas effect of shale gas can be lowered to the level of that of coal if methane emissions are kept low using existing technologies. Further reducing the greenhouse gas effect of shale gas by storing CO2 in depleted shale gas reservoirs is also discussed, with the conclusion that more CO2 than the equivalent CO2 emitted by the extracted shale gas could be stored in the reservoirs at significantly reduced cost. - Highlights: ► The long-term greenhouse gas footprint of shale gas is smaller than that of coal. ► Carbon capture and storage should be considered for fossil fuels including shale gas. ► Depleted shale gas fields could store more CO2 than the equivalent emissions. ► Linking shale gas development with CO2 storage could largely reduce the total cost.
Wenwu Xia; Mike D. Burnaman; John Shelton
The understanding from the conventional geochemistry and geology analysis is very different when trying to apply them to shale gas plays. This paper is a summary for U.S. shale gas plays on geochemistry and geologic analysis application, and real field data from active U.S. shale gas plays is used in the discussion of different concepts.
Compton, L. E. (Inventor)
Significant improvement in oil shale extraction under supercritical conditions is provided by extracting the shale at a temperature below 400 C, such as from about 250 C to about 350 C, with a solvent having a Hildebrand solubility parameter within 1 to 2 Hb of the solubility parameter for oil shale bitumen.
Full Text Available Shale gas reservoirs generally need to be fractured massively to reach the industrial production, however, the flowback ratio of fractured shale gas wells is low. In view of this issue, the effects of natural fracture spacing, fracture conductivity, fracturing scale, pressure coefficient and shut-in time on the flowback ratio were examined by means of numerical simulation and experiments jointly, and the causes of flowback difficulty of shale gas wells were analyzed. The results show that the flowback ratio increases with the increase of natural fracture spacing, fracture conductivity and pressure coefficient and decreases with the increase of fracturing scale and shut-in time. From the perspective of microscopic mechanism, when water enters micro-cracks of the matrix through the capillary self-absorbing effect, the original hydrogen bonds between the particles are replaced by the hydroxyl group, namely, hydration effect, giving rise to the growth of new micro-cracks and propagation of main fractures, and complex fracture networks, so a large proportion of water cannot flow back, resulting in a low flowback ratio. For shale gas well fracturing generally has small fracture space, low fracture conductivity and big fracturing volume, a large proportion of the injected water will be held in the very complex fracture network with a big specific area, and unable to flow back. It is concluded that the flowback ratio of fractured shale gas wells is affected by several factors, so it is not necessary to seek high flowback ratio deliberately, and shale gas wells with low flowback ratio, instead, usually have high production.
The objective of this study was to examine the mineralogy and leachate chemistry of three combusted oil shales (two Green River Formation and one New Albany) in a laboratory weathering environment using the humidity cell technique. The mineralogy of the combusted western oil shales (Green River Formation) is process dependent. In general, processing resulted in the formation of anhydrite, lime, periclase, and hematite. During the initial stages of weathering, lime, periclase, and hematite. During the initial stages of weathering, lime, periclase, and anhydrite dissolve and ettringite precipitates. The initial leachates are highly alkaline, saline, and dominated by Na, hydroxide, and SO4. As weathering continues, ettringite precipitates. The initial leachates are highly alkaline, saline, and dominated by Na, hydroxide, and SO4. As weathering continues, ettringite dissolves, gypsum and calcite precipitate, and the leachates are dominated by Mg, SO4, and CO3. Leachate pH is rapidly reduced to between 8.5 and 9 with leaching. The combusted eastern oil shale (New Albany) is composed of quartz, illite, hematite, and orthoclase. Weathering results in the precipitation of gypsum. The combusted eastern oil shale did not display a potential to produce acid drainage. Leachate chemistry was dominated by Ca and SO4. Element concentrations continually decreased with weathering. IN a western disposal environment receiving minimal atmospheric precipitation, spent oil shale will remain in the initial stages of weathering, and highly alkaline and saline conditions will dominate leachate chemistry. In an eastern disposal environment, soluble salts will be rapidly removed from the spent oil shale to potentially affect the surrounding environment
MICHAEL H. STEPHENSON
According to the U.S. Energy Information Administration, shale gas will provide half of the United States’ domestic gas by 2035. The United States has already moved from being one of the world's largest importers of gas to being self-sufficient in less than a decade, bringing hundreds of thousands of jobs and attracting back companies that long ago left America in search of cheap manufacturing costs. But the increase in shale gas extraction has also had an environmental cost. There is clear s...
Gaines, Robert R.; Hammarlund, Emma U.; Hou, Xianguang;
. Sulfur isotope evidence from sedimentary pyrites reveals that the exquisite fossilization of organic remains as carbonaceous compressions resulted from early inhibition of microbial activity in the sediments by means of oxidant deprivation. Low sulfate concentrations in the global ocean and low......, provided by bed-capping cements that were emplaced at the seafloor, is a feature that is shared among Burgess Shale-type deposits, and resulted from the unusually high alkalinity of Cambrian oceans. Thus, Burgess Shale-type preservation of soft-bodied fossil assemblages worldwide was promoted by unique...
The High-Temperature Gas-Cooled Reactor (HTGR) utilizes a graphite-moderated core and helium as primary coolant. Developed for electric power production, the 842-MW(t) (330-MW(e)) Fort St. Vrain plant is currently operating at Platteville, Colorado. Studies have been performed that couple steam produced at 5400C (10000F) and 17 MPa (2500 psia) to two oil shale processes: the Paraho indirect retorting and the Marathon direct steam retorting. The plant, consisting of two 1170-MW(t) HTGR's, would also produce electric power for other shale operations. Results show economic and environmental advantages for the coupling
The High-Temperature Gas-Cooled Reactor (HTGR) utilizes a graphite-moderated core and helium as primary coolant. Developed for electric power production, the 842-MW(t) [330-MW(e)] Fort St. Vrain plant is currently operating at Platteville, Colorado. Studies have been performed that couple steam produced at 5400C (10000F) and 17 MPa (2500 psia) to two oil shale processes: the Paraho indirect retorting and the Marathon direct steam retorting. The plant, consisting of two 1170-MW(t) HTGR's, would also produce electric power for other shale operations. Results show economic and environmental advantages for the coupling
The purpose of this study was to create a simple mathematical model to describe as well as possible the structure of a mining enterprise. The model differs from previous ones in some methodical complements and describes better the current situation in the oil shale industry. In the model expenses are divided into variable and fixed costs for each mining enterprise. Several calculations have been made to optimize sale of oil shale for both power industry, and oil producers. This paper is a summary of M.Sc theses defended at department of Mining of Tallinn Technical University in January 2002
Fangwen Chen; Shuangfang Lu; Xue Ding
The organopores play an important role in determining total volume of hydrocarbons in shale gas reservoir. The Lower Silurian Longmaxi Shale in southeast Chongqing was selected as a case to confirm the contribution of organopores (microscale and nanoscale pores within organic matters in shale) formed by hydrocarbon generation to total volume of hydrocarbons in shale gas reservoir. Using the material balance principle combined with chemical kinetics methods, an evaluation model of organoporosi...
Foster, H.; Worrall, F.; Gluyas, J.; Morgan, C.; Fraser, J.
Worldwide deposits of oil shales are thought to represent ~3 trillion barrels of oil. Jordanian oil shale deposits are extensive and of high quality, and could represent 100 billion barrels of oil, leading to much interest and activity in the development of these deposits. The exploitation of oil shales has raised a number of environmental concerns including: land use, waste disposal, water consumption, and greenhouse gas emissions. The dry retorting of oil shales can overcome a number of the environmental impacts, but this leaves concerns over management of spent oil shale and CO2 production. In this study we propose that the spent oil shale can be used to sequester CO2 from the retorting process. Here we show that by conducting experiments using high pressure reaction facilities, we can achieve successful carbonation of spent oil shale. High pressure reactor facilities in the Department of Earth Sciences, Durham University, are capable of reacting solids with a range of fluids up to 15 MPa and 350°C, being specially designed for research with supercritical fluids. Jordanian spent oil shale was reacted with high pressure CO2 in order to assess whether there is potential for sequestration. Fresh and reacted materials were then examined by: Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermogravimetric Analysis (TGA), X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) methods. Jordanian spent oil shale was found to sequester up to 5.8 wt % CO2, on reacting under supercritical conditions, which is 90% of the theoretical carbonation. Jordanian spent oil shale is composed of a large proportion of CaCO3, which on retorting decomposes, forming CaSO4 and Ca-oxides which are the focus of carbonation reactions. A factorially designed experiment was used to test different factors on the extent of carbonation, including: pressure; temperature; duration; and the water content. Analysis of Variance (ANOVA) techniques were then used to determine the significance of
The discovery of shale gas reopens the fierce struggle for energy control at regional and global level and reconfigures the geostrategic interests map of the great powers. The new technology of unconventional gas extraction, hydraulic fracturing has supporters andopponents on its size. But at the gate of scientific discoveries beats a new form of energy: the energy based on thorium. Cheaper, safer, less polluting.
After having recalled the definition and origin of shale gases, the different non conventional gases and their exploitation techniques (hydraulic fracturing and horizontal drilling) this report examines whether these gases are an opportunity for France. Some characteristics and data of the fossil and gas markets are presented and commented: world primary energy consumption, proved reserves of non conventional gases and their locations, European regions which may possess reserves of shale gases and coal-bed methane, origins of gas imports in France. The second part addresses shale gas deposits and their exploitation: discussion of the influence of the various rock parameters, evolution of production. The third part discusses the exploitation techniques and specific drilling tools. The issue of exploitation safety and security is addressed as well as the associated controversies: about the pollution of underground waters, about the fact that deep drillings result in pollution, about the risks associated with hydraulic fracturing and injections of chemical products, about the hold on ground and site degradation, about water consumption, about pollution due to gas pipeline leakage, about seismic risk, about noise drawbacks, about risks for health, about exploration and production authorization and license, and about air pollution and climate. The last part addresses the French situation and its future: status of the energy bill, recommendations made by a previous government, cancellation of authorizations, etc. Other information are provided in appendix about non conventional hydrocarbons, about shale gas exploitation in the USA, and about the Lacq gas
During fiscal year 1992, the reserves generated $473 million in revenues, a $181 million decrease from the fiscal year 1991 revenues, primarily due to significant decreases in oil and natural gas prices. Total costs were $200 million, resulting in net cash flow of $273 million, compared with $454 million in fiscal year 1991. From 1976 through fiscal year 1992, the Naval Petroleum and Oil Shale Reserves generated more than $15 billion in revenues and a net operating income after costs of $12.5 billion. In fiscal year 1992, production at the Naval Petroleum Reserves at maximum efficient rates yielded 26 million barrels of crude oil, 119 billion cubic feet of natural gas, and 164 million gallons of natural gas liquids. From April to November 1992, senior managers from the Naval Petroleum and Oil Shale Reserves held a series of three workshops in Boulder, Colorado, in order to build a comprehensive Strategic Plan as required by Secretary of Energy Notice 25A-91. Other highlights are presented for the following: Naval Petroleum Reserve No. 1--production achievements, crude oil shipments to the strategic petroleum reserve, horizontal drilling, shallow oil zone gas injection project, environment and safety, and vanpool program; Naval Petroleum Reserve No. 2--new management and operating contractor and exploration drilling; Naval Petroleum Reserve No. 3--steamflood; Naval Oil Shale Reserves--protection program; and Tiger Team environmental assessment of the Naval Petroleum and Oil Shale Reserves in Colorado, Utah, and Wyoming
Kuushraa, V.A.; Wicks, D.E.; Sawyer, W.K.; Esposito, P.R.
The technically recoverable gas from Devonian shale (Lower and Middle Huron) in Ohio is estimated to range from 6.2 to 22.5 Tcf, depending on the stimulation method and pattern size selected. This estimate of recovery is based on the integration of the most recent data and research on the Devonian Age gas-bearing shales of Ohio. This includes: (1) a compilation of the latest geologic and reservoir data for the gas in-place; (2) analysis of the key productive mechanisms; and, (3) examination of alternative stimulation and production strategies for most efficiently recovering this gas. Beyond a comprehensive assembly of the data and calculation of the technically recoverable gas, the key findings of this report are as follows: a substantial volume of gas is technically recoverable, although advanced (larger scale) stimulation technology will be required to reach economically attractive gas production rates in much of the state; well spacing in certain of the areas can be reduced by half from the traditional 150 to 160 acres per well without severely impairing per-well gas recovery; and, due to the relatively high degree of permeability anisotropy in the Devonian shales, a rectangular, generally 3 by 1 well pattern leads to optimum recovery. Finally, although a consistent geological interpretation and model have been constructed for the Lower and Middle Huron intervals of the Ohio Devonian shale, this interpretation is founded on limited data currently available, along with numerous technical assumptions that need further verification. 11 references, 21 figures, 32 tables.
Focusing primarily on papers and books discussing the evolutionary and systematic interpretation of the Cambrian animal fossils from the Burgess Shale fauna, this paper explores the role of epistemic values in the context of a discipline (paleontology) striving to establish scientific authority w...
The chemistry of groundwaters is one of the most important parameters in determining the mobility of species within a rock formation. A three pronged approach was used to determine the composition of, and geochemical controls, on groundwaters specifically within shale formations: (1) available data were collected from the literature, the US Geological Survey WATSTORE data base, and field sampling, (2) the geochemical modeling code EQ3/6 was used to simulate interaction of various shales and groundwaters, and (3) several types of shale were reacted with synthetic groundwaters in the laboratory. The comparison of model results to field and laboratory data provide a means of validating the models, as well as a means of deconvoluting complex field interactions. Results suggest that groundwaters in shales have a wide range in composition and are primarily of the Na-Cl-HCO3- type. The constancy of the Na:Cl (molar) ratio at 1:1 and the Ca:Mg ratio from 3:1 to 1:1 suggests the importance of halite and carbonates in controlling groundwater compositions. In agreement with the reaction path modeling, most of the groundwaters are neutral to slightly alkaline at low temperatures. Model and experimental results suggest that reaction (1) at elevated temperatures, or (2) in the presence of oxygen will lead to more acidic conditions. Some acetate was found to be produced in the experiments; depending on the constraints applied, large amounts of acetate were produced in the model results. 13 refs., 1 tab
Full Text Available The development of the shale industry is gaining momentum and hence the analysis of chemical hazards to the environment and health of the local population is extremely timely and important. Chemical hazards are created during the exploitation of all minerals, but in the case of shale gas production, there is much more uncertainty as regards to the effects of new technologies application. American experience suggests the increasing risk of environmental contamination, mainly groundwater. The greatest concern is the incomplete knowledge of the composition of fluids used for fracturing shale rock and unpredictability of long-term effects of hydraulic fracturing for the environment and health of residents. High population density in the old continent causes the problem of chemical hazards which is much larger than in the USA. Despite the growing public discontent data on this subject are limited. First of all, there is no epidemiological studies to assess the relationship between risk factors, such as air and water pollution, and health effects in populations living in close proximity to gas wells. The aim of this article is to identify and discuss existing concepts on the sources of environmental contamination, an indication of the environment elements under pressure and potential health risks arising from shale gas extraction. Med Pr 2015;66(1:99–117
De Jong, T.P.R.; Mesina, M.B.; Kuilman, W.
The efficiency with which an electromagnetic sensor array is able to distinguish density and ash content of coal and shale mixtures was determined experimentally. The investigated sensor was originally designed for automatic metal detection and sorting in industrial glass recycle processing, where i
Ouadfeul, Sid-Ali; Aliouane, Leila
In this paper, a tentative of shale gas reservoirs characterization enhancement from well-logs data using neural network is established. The goal is to predict the Total Organic carbon (TOC) in boreholes where the TOC core rock or TOC well-log measurement does not exist. The Multilayer perceptron (MLP) neural network with three layers is established. The MLP input layer is constituted with five neurons corresponding to the Bulk density, Neutron porosity, sonic P wave slowness and photoelectric absorption coefficient. The hidden layer is forms with nine neurons and the output layer is formed with one neuron corresponding to the TOC log. Application to two boreholes located in Barnett shale formation where a well A is used as a pilot and a well B is used for propagation shows clearly the efficiency of the neural network method to improve the shale gas reservoirs characterization. The established formalism plays a high important role in the shale gas plays economy and long term gas energy production.
As a moratorium has been decided by the French ministry of the Environment about shale gas exploration permits, this article briefly states that this exploration and exploitation would have a limited impact on landscape, would need a good insulation of wells with respect to ground waters, a debate about water consumption and pollution, and about the use of chemical products for fracturing rocks
Apparatus for distilling materials such as shale comprising a heater of tubular elements and means for circulating a heating medium over one surface of the tubes, the gases from the material under treatment being circulated over the other surface of the tubes and then returned from the heater to the chamber to assist in heating the material under treatment.
Rabe, Claudio; Araujo, Ewerton M.P.; Fontoura, Sergio A.B. da [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Civil. Grupo de Tecnologia e Engenharia de Petroleo (GTEP)
This paper presents a petrographical characterization of shales from Albacora, Marlim and Marlim Sul fields (offshore Campos Basin, Brazil). The characterization program included petrography analysis of thin section of undisturbed shale samples, scanning electron microscope (SEM) images and energy dispersive spectrometry (EDS) analysis. The tests were realized with the purpose of obtaining information to observe the nature of the rock microstructure. From the results presented herein, the shales can be described as silty and calciferous. The description of the thin sections indicated that all the shale samples are very similar from the compositional and textural point of view. The samples are rich in clay minerals, that show small size grains and seem homogeneous, and carbonatic cement. The samples are constituted by calcite, quartz, kaolinite, smecite, illite, illite/smectite, kaolinite/illite/smectite, feldspar, plagioclase, dolomite, chlorite and pyrite. The samples showed a great amount of calcium, resultant from the microfossils, that covers partially the clay minerals. Pyrite is also observed as small grains disperse throughout the sample with form of agglomerated pyrite framboids, cubo-octahedral and octahedral crystals. The EDS show the presence of picks of Si, Al, Mg, K and Na particles, indicating the presence of clay minerals, calcite, pyrite and chlorite. (author)
Full Text Available The depositional environment of organic-rich shale and the related tectonic evolution in China are rather different from those in North America. In China, organic-rich shale is not only deposited in marine environment, but also in non-marine environment: marine-continental transitional environment and lacustrine environment. Through analyzing large amount of outcrops and well cores, the geologic features of organic-rich shale, including mineral composition, organic matter richness and type, and lithology stratigraphy, were analyzed, indicating very special characteristics. Meanwhile, the more complex and active tectonic movements in China lead to strong deformation and erosion of organic-rich shale, well-development of fractures and faults, and higher thermal maturity and serious heterogeneity. Co-existence of shale gas, tight sand gas, and coal bed methane (CBM proposes a new topic: whether it is possible to co-produce these gases to reduce cost. Based on the geologic features, the primary production issues of shale gas in China were discussed with suggestions.
Yiwen Ju; Guochang Wang; Hongling Bu; Qingguang Li; Zhifeng Yan
The depositional environment of organic-rich shale and the related tectonic evolution in China are rather different from those in North America. In China, organic-rich shale is not only deposited in marine environment, but also in non-marine environment: marine-continental transitional environment and lacustrine environment. Through analyzing large amount of outcrops and well cores, the geologic fea-tures of organic-rich shale, including mineral composition, organic matter richness and type, and li-thology stratigraphy, were analyzed, indicating very special characteristics. Meanwhile, the more complex and active tectonic movements in China lead to strong deformation and erosion of organic-rich shale, well-development of fractures and faults, and higher thermal maturity and serious heterogeneity. Co-existence of shale gas, tight sand gas, and coal bed methane (CBM) proposes a new topic:whether it is possible to co-produce these gases to reduce cost. Based on the geologic features, the primary pro-duction issues of shale gas in China were discussed with suggestions.
Al-Harahsheh, Mohammad; Alnawafleh, Hani [Department of Mining Engineering, College of Mining and Environmental Engineering, Al-Hussein Bin Talal University, Ma' an 20 (Jordan); Kingman, Sam; Saeid, Abdurrahman; Robinson, John; Dimitrakis, Georgios [Process and Environmental Research Division Faculty of Engineering, University of Nottingham, Nottingham, NG7 2RD (United Kingdom)
Microwave heating has been suggested by various authors as a suitable technology for extraction of organic material from oil shales. However, one of the limiting factors in the development of this technology is a lack of accurate dielectric property data for design purposes. In this study the dielectric behaviour of El-lajun oil shale is quantified. The dielectric constant and loss factor of El-lajun oil shale were measured at 2470 and 912 MHz using the cavity perturbation technique. The effects of organic content, temperature, and moisture content on the microwave heating efficiency were quantified. Coaxial probe technique was also employed to study the effect of frequency on dielectric properties of oil shale. Generally, it was found that all samples were of low dielectric loss at room temperature with the imaginary part of permittivity falling significantly after the moisture was removed. This suggests that the major contribution in the dielectric loss is due to the presence of free and/or interlayer water. It was found that both the real and imaginary part of complex permittivity increased with a rise in temperature from 20 up to 80 C, then dropped significantly at about 100 C before staying approximately constant up to a temperature of about 480 C. From this temperature both the real and imaginary parts of complex permittivity increased sharply with further increase in temperature. An attempt was also made to correlate the dielectric properties of the bulk shale sample with the organic content. However, no correlation between dielectric properties and organic matter content was found. (author)
Karakitsios, Vasileios; Agiadi, Konstantina
It is clear that we are gradually running out of new sedimentary basins to explore for conventional oil and gas and that the reserves of conventional oil, which can be produced cheaply, are limited. This is the reason why several major oil companies invest in what are often called unconventional hydrocarbons: mainly oil shales, heavy oil, tar sand and shale gas. In western Greece exist important oil and gas shale reservoirs which must be added to its hydrocarbon potential1,2. Regarding oil shales, Western Greece presents significant underground immature, or close to the early maturation stage, source rocks with black shale composition. These source rock oils may be produced by applying an in-situ conversion process (ICP). A modern technology, yet unproven at a commercial scale, is the thermally conductive in-situ conversion technology, developed by Shell3. Since most of western Greece source rocks are black shales with high organic content, those, which are immature or close to the maturity limit have sufficient thickness and are located below 1500 meters depth, may be converted artificially by in situ pyrolysis. In western Greece, there are several extensive areas with these characteristics, which may be subject of exploitation in the future2. Shale gas reservoirs in Western Greece are quite possibly present in all areas where shales occur below the ground-water level, with significant extent and organic matter content greater than 1%, and during their geological history, were found under conditions corresponding to the gas window (generally at depths over 5,000 to 6,000m). Western Greece contains argillaceous source rocks, found within the gas window, from which shale gas may be produced and consequently these rocks represent exploitable shale gas reservoirs. Considering the inevitable increase in crude oil prices, it is expected that at some point soon Western Greece shales will most probably be targeted. Exploration for conventional petroleum reservoirs
Barnhoorn, Auke; Primarini, Mutia; Houben, Maartje
The formation of a fracture network in rocks has a crucial control on the flow behaviour of fluids. In addition, an existing network of fractures , influences the propagation of new fractures during e.g. hydraulic fracturing or during a seismic event. Understanding of the type and characteristics of the fracture network that will be formed during e.g. hydraulic fracturing is thus crucial to better predict the outcome of a hydraulic fracturing job. For this, knowledge of the rock properties is crucial. The brittleness index is often used as a rock property that can be used to predict the fracturing behaviour of a rock for e.g. hydraulic fracturing of shales. Various terminologies of the brittleness index (BI1, BI2 and BI3) exist based on mineralogy, elastic constants and stress-strain behaviour (Jin et al., 2014, Jarvie et al., 2007 and Holt et al., 2011). A maximum brittleness index of 1 predicts very good and efficient fracturing behaviour while a minimum brittleness index of 0 predicts a much more ductile shale behaviour. Here, we have performed systematic petrophysical, acoustic and geomechanical analyses on a set of shale samples from Whitby (UK) and we have determined the three different brittleness indices on each sample by performing all the analyses on each of the samples. We show that each of the three brittleness indices are very different for the same sample and as such it can be concluded that the brittleness index is not a good predictor of the fracturing behaviour of shales. The brittleness index based on the acoustic data (BI1) all lie around values of 0.5, while the brittleness index based on the stress strain data (BI2) give an average brittleness index around 0.75, whereas the mineralogy brittleness index (BI3) predict values below 0.2. This shows that by using different estimates of the brittleness index different decisions can be made for hydraulic fracturing. If we would rely on the mineralogy (BI3), the Whitby mudstone is not a suitable
Shen, J.C.; Huang, W.L. [Chinese Petroleum Corp, Miaoli (Taiwan)
The distribution of hopanoids and alkanes in bitumen extracts of coals, coaly shales, and shales from northwestern Taiwan has been measured to assess the maturity of potential petroleum source rocks in the studied area. The C31 homohopane isomers of the studied coals and coaly shales attain equilibrium at maturity corresponding to 0.6% Ro measured in coals or 0.65% Ro in adjacent shales. A proposed parameter using hopanoid ratios reveals a more consistent trend and approaches a steady value at maturity similar to the C31 homohopane isomer ratio. The results show that the onset of the main phase of petroleum generation in northwestern Taiwan takes place at maturity corresponding to VR of 0.6% Ro measured in coals or coaly shales and probably higher VR in shales. The distribution of pristane, phytane n-C17 and n-C18 confirms the validity of the conventional maturity indicators if the samples are from the same source, but shows depositionalor organic-source controls. The source influence on the phytane/n-C18 ratio appears to be larger than that on the pristane/n-C17 ratio. The phytane/n-C18 ratio is also less sensitive to maturity than that of the pristane/n-C17 ratio. The pristane/phytane ratios in the studied coals and coaly shales, in contrast to the pristane/n-C-17 ratio, continue to decrease to maturities beyond the oil window up to 1.5% Ro and therefore may be applicable to high maturity sources.
As the commercial success of shale gas exploitation in USA, there also amount of water resource depleted and some potential environmental problems exist. According to the low pore pressure, low porosity, low permeability characteristic of shale gas reservoir, and the successful experience of CO2 sequestration and enhanced methane recovery in the unminable coalbed, incorporating the differential adsorption capacity of CO2 and CH4 in shale, the injection technology of CO2 into shale gas reservoir for storage and enhancing shale gas recovery was pro- posed. Then the technology, economic and safety feasibility of this solution was analyzed. The result suggested that the shales adsorb more carbon dioxide than methane at reservoir conditions, the methane can be displaced by carbon dioxide injection and enhanced shale gas recovery could be achieved. A model for calculation of CO2 storage capacity was development, the preliminary estimate of the CO2 storage potential was 2.11∼4.32 times of the shale gas. So Injection of carbon di- oxide into shale gas reservoir is a promising technology which has the potential to enhance shale gas recovery, while simultaneously sequestering amount of CO2. (authors)
Over the past decade, the rapid increase in shale gas and shale oil production in the United States has profoundly changed energy markets in North America, and has led to a significant decrease in American natural gas prices. The possible existence of large shale deposits in Europe, mainly in France, Poland and the United Kingdom, has fostered speculation on whether the 'shale revolution', and its accompanying macro-economic impacts, could be duplicated in Europe. However, a number of uncertainties, notably geological, technological and regulatory, make this possibility unclear. We present a techno-economic model, SHERPA (Shale Exploitation and Recovery Projection and Analysis), to analyze the main determinants of the profitability of shale wells and plays. We calibrate our model using production data from the leading American shale plays. We use SHERPA to estimate three shale gas production scenarios exploring different sets of geological and technical hypotheses for the largest potential holder of shale gas deposits in Europe, France. Even considering that the geology of the potential French shale deposits is favorable to commercial extraction, we find that under assumptions calibrated on U.S. production data, natural gas could be produced at a high breakeven price of $8.6 per MMBtu, and over a 45 year time-frame have a net present value of $19.6 billion - less than 1% of 2012 French GDP. However, the specificities of the European context, notably high deposit depth and stricter environmental regulations, could increase drilling costs and further decrease this low profitability. We find that a 40% premium over American drilling costs would make shale gas extraction uneconomical. Absent extreme well productivity, it appears very difficult for shale gas extraction to have an impact on European energy markets comparable to the American shale revolution. (author)
Veil, J. A. (Environmental Science Division)
Water issues continue to play an important role in producing natural gas from shale formations. This report examines water issues relating to shale gas production in the Fayetteville Shale. In particular, the report focuses on how gas producers obtain water supplies used for drilling and hydraulically fracturing wells, how that water is transported to the well sites and stored, and how the wastewater from the wells (flowback and produced water) is managed. Last year, Argonne National Laboratory made a similar evaluation of water issues in the Marcellus Shale (Veil 2010). Gas production in the Marcellus Shale involves at least three states, many oil and gas operators, and multiple wastewater management options. Consequently, Veil (2010) provided extensive information on water. This current study is less complicated for several reasons: (1) gas production in the Fayetteville Shale is somewhat more mature and stable than production in the Marcellus Shale; (2) the Fayetteville Shale underlies a single state (Arkansas); (3) there are only a few gas producers that operate the large majority of the wells in the Fayetteville Shale; (4) much of the water management information relating to the Marcellus Shale also applies to the Fayetteville Shale, therefore, it can be referenced from Veil (2010) rather than being recreated here; and (5) the author has previously published a report on the Fayetteville Shale (Veil 2007) and has helped to develop an informational website on the Fayetteville Shale (Argonne and University of Arkansas 2008), both of these sources, which are relevant to the subject of this report, are cited as references.
Oil shale mining production reached its maximum level of 31.35·106 tonnes per year in 1980. After the eighties there was a steady decline in mining. The first scientific prognoses of the inescapable decrease in oil shale mining were published in 1988. According to this, the Estonian oil shale industry would vanish in the third decade of the next century. From the beginning of the nineties, the consumption and export of electricity have dropped in Estonia. The minimum level of oil shale mining was 13.5·106 tonnes per year. This occurred in 1994/1995. Some increase in consumption of electric power and oil shale began at the end of 1995. Oil shale processing began to increase gradually in 1993. Oil shale is the most important fuel in Estonia today. In 1997, oil shale provided 76% of Estonia's primary energy supply and accounted for 57% of its economic value. Oil shale is the cheapest fuel in Estonia. Nowadays, oil shale provides an essential part of the fuel supply in Estonia because it is considerably cheaper than other fuels. Oil shale costs EEK 12.16 per G J. At the same time, coal costs EEK 23.41 per G J and peat costs EEK 14.80 per G J (year 1997). There are three important customers of oil shale: the electric power company Eesti Energia, the oil processing company Kiviter and the factory Kunda Nordic Cement. In 1995, the power company utilised 81% of the oil shale mass and 77% of its heating value. The state energy policy inhibits increases in the oil shale price even though the mining infrastructure is decaying. Government price policies subside oil shale processing. The energy of oil shale processing is 1.9 times cheaper than the heating value of raw oil shale for power stations. It could be considered as a state subsidisation of oil and cement export at the expense of electricity. The subsidy assigned to oil processing was of EEK 124·106 and to the cement industry of EEK 8.4·106 in year 1997 (based on heating value). State regulation of prices and
Annevelink, M P J A; Meesters, J A J; Hendriks, A J
Shale gas development potentially contaminates both air and water compartments. To assist in governmental decision-making on future explorations, we reviewed scattered information on activities, emissions and concentrations related to shale gas development. We compared concentrations from monitoring programmes to quality standards as a first indication of environmental risks. Emissions could not be estimated accurately because of incomparable and insufficient data. Air and water concentrations range widely. Poor wastewater treatment posed the highest risk with concentrations exceeding both Natural Background Values (NBVs) by a factor 1000-10,000 and Lowest Quality Standards (LQSs) by a factor 10-100. Concentrations of salts, metals, volatile organic compounds (VOCs) and hydrocarbons exceeded aquatic ecotoxicological water standards. Future research must focus on measuring aerial and aquatic emissions of toxic chemicals, generalisation of experimental setups and measurement technics and further human and ecological risk assessment. PMID:26845179
Cleveland Cliffs Iron Company was awarded a DOE contract in December 1977 for field retrieval and laboratory analysis of cores from the Devonian shales of the following eleven states: Michigan, Illinois, Indiana, Ohio, New York, Pennsylvania, West Virginia, Maryland, Kentucky, Tennessee and Virginia. The purpose of this project is to explore these areas to determine the amount of natural gas being produced from the Devonian shales. The physical properties testing of the rock specimens were performed under subcontract at Michigan Technological University (MTU). The study also included LANDSAT information, geochemical research, structural sedimentary and tectonic data. Following the introduction, and background of the project this report covers the following: field retrieval procedures; laboratory procedures; geologic analysis (by state); references and appendices. (ATT)
This paper analysis the stability of the mining blocks in Estonian oil shale mines, where the room-and-pillar mining system is used. The pillars are arranged in a singular grid. The oil shale bed is embedded at the depth of 40-75 m. The processes in overburden rocks and pillars have caused the subsidence of the ground surface. The conditional thickness and sliding rectangle methods performed calculations. The results are presented by conditional thickness contours. Error does not exceed 4%. Model allows determining the parameters of spontaneous collapse of the pillars and surface subsidence. The surface subsidence parameters will be determined by conventional calculation scheme. Proposed method suits for stability analysis, failure prognosis and monitoring. 8 refs
In view of the difficulties encountered in rendering soluble the uranium content of shales worked in the Vosges region, and in their filtration after attack, the effects of heat treatment at high temperatures (300 to 600 deg. C) on these two factors is discussed. The first part deals with tests in static beds, the second in fluid beds. In both cases calorie recovery is discussed. The treatment improves filtration but not solubility. (author)
This paper describes the increasing role of natural gas in the energy mix in Canada. It is suggested that there is at least 100 years supply of natural gas at the current production levels. Natural gas is clean, versatile, affordable, reliable and safe. Availability of large quantities of shale gas has resulted in resource estimates to grow significantly and rapidly and new technologies have enabled economics.
Oil is extracted from grinded hot oil shale by the treatment with an organic liquid, e.g. gas oil, at 350 to 4100C and elevated pressure in the presence of hydrogen. The admixed organic liquid is separated from the oil contained in the oil shake in an extraction vessel with benzine as the extracting agent. The mixture from the extracted components of the oil-shake and the extracting agent is dried in a drying vessel with low pressure steam. (HGOE)
De Joode, J.; Plomp, A.J.; Ozdemir, O. [ECN Policy Studies, Petten (Netherlands)
The outline of the presentation shows the following elements: Introduction (Shale gas revolution in US and the situation in the EU); What could be the impact of potential shale gas developments on the European gas market?; How may shale gas developments affect the role of gas in the transition of the power sector?; and Key messages. The key messages are (1) Prospects for European shale gas widely differ from US case (different reserve potential, different competition, different market dynamics); (2) Shale gas is unlikely to be a game changer in Europe; and (3) Impact of shale gas on energy transition in the medium and long term crucially depends on gas vs. coal prices and the 'penalty' on CO2 emissions.
Noridin, J. S.; Donovan, R.; Trudell, L.; Dean, J.; Blevins, A.; Harrington, L. W.; James, R.; Berdan, G.
The Western Research Institute plan for addressing oil shale plant siting methodology calls for identifying the available resources such as oil shale, water, topography and transportation, and human resources. Restrictions on development are addressed: land ownership, land use, water rights, environment, socioeconomics, culture, health and safety, and other institutional restrictions. Descriptions of the technologies for development of oil shale resources are included. The impacts of oil shale development on the environment, socioeconomic structure, water availability, and other conditions are discussed. Finally, the Western Research Institute plan proposes to integrate these topics to develop a flow chart for oil shale plant siting. Western Research Institute has (1) identified relative topics for shale oil plant siting, (2) surveyed both published and unpublished information, and (3) identified data gaps and research needs. 910 refs., 3 figs., 30 tabs.
A digital map of Estonian oil shale mining was created for joining the data about technological, environmental, and social limitations in the deposit. For evaluating potential resource of oil shale, based on borehole database, its amount, tonnage and energy were calculated. Thereafter the quantity of economical oil shale for power plants and shale oil resource were calculated. Energy rating is the most important factor for determining oil shale reserves in the case of using it for electricity generation. In the case of oil production, data on oil yield and potential resources in oil shale are the most important figures to determine the value of the deposit. Basing on the models, oil resource has been calculated. Resource data can be used for composing master plans for the deposit considering both power generation and oil production. The data can be also used for composing development plans of mines and for logistics calculations. (author)
Production of oil shale-based electricity covers Estonian electricity consumption and enables also to export electricity. Oil shale-based electricity production is by now competitive on the electricity market of the Baltic States and of the neighboring EU Member States. However, production of oil shale-based electricity has low energy efficiency, demands large investments for renovation and has high environmental risks. Taxation of environmental damage will be more severe in the future, lowering the competitiveness of oil shale-based electricity. Therefore, the key issue of sustainable development of Estonian energy sector is reduction of the environmental damage of the oil shale-based electricity production, or reduction of the share of oil shale in the energy balance at the expense of other energy resources, especially renewable energy. (author)
Parameters for the adsorption of Xe and Kr on shales and related samples have been measured by a method that uses a mass spectrometer as a manometer. The gas partial pressures used were 10-11 atm or less; the corresponding adsorption coverages are only small fractions of a monolayer, and Henry's Law behavior is expected and observed. Heats of adsorption in the range 2 to 7 kcal/mol were observed. Henry constants of the order of magnitude 1 cm3 STP g-1 atm-1 at 0 to 250C are obtained by extrapolation. Adsorption properties are variable by sample, but the general range suggests that shales might be sufficiently good adsorbents that equilibrium adsorption with modern air may account for a nontrivial fraction of the atmospheric inventory of Xe (perhaps even Kr). It seems doubtful, however, that this effect can account for the deficiency of atmospheric Xe in comparison with the planetary gas patterns observed in meteorites. If gas is adsorbed on interior surfaces in shale clays and can communicate with sample exteriors only through very narrow channels, and thus only very slowly, equilibrium adsorption may make substantial contributions to experimentally observed 'trapped' gases without the need for any further trapping mechanism. (author)
Mohammad O. Eshkalak
Full Text Available Production from unconventional reservoirs has gained an increased attention among operators in North America during past years and is believed to secure the energy demand for next decades. Economic production from unconventional reservoirs is mainly attributed to realizing the complexities and key fundamentals of reservoir formation properties. Geomechanical well logs (including well logs such as total minimum horizontal stress, Poisson’s ratio, and Young, shear, and bulk modulus are secured source to obtain these substantial shale rock properties. However, running these geomechanical well logs for the entire asset is not a common practice that is associated with the cost of obtaining these well logs. In this study, synthetic geomechanical well logs for a Marcellus shale asset located in southern Pennsylvania are generated using data-driven modeling. Full-field geomechanical distributions (map and volumes of this asset for five geomechanical properties are also created using general geostatistical methods coupled with data-driven modeling. The results showed that synthetic geomechanical well logs and real field logs fall into each other when the input dataset has not seen the real field well logs. Geomechanical distributions of the Marcellus shale improved significantly when full-field data is incorporated in the geostatistical calculations.
During the years 1998-2001 geotechnical processes in closed underground oil shale mines and open casts were investigated. In addition to kukersite oil shale deposit, the closed Sillamaee uranium (Dictyonema shale) mine was prospected. The main tools and methods included mine plans, aerial photographs and Geographical Information System data. 290 km2 of underground and 130 km2of strip-mined areas were studied. The mining maps of Estonian underground and surface mines were created. The stability of underground mined area, where room-and-pillar method was used, was the main objective of the study. It was studied with the help of aerial photographs, mine drawings, maps of quaternary sediments and mathematical modeling of rock failure. The main results are: 20 % of subsidences remain undiscovered and 42 % of subsidence occurrences have no remarkable influence to the land cover; the probability of subsidence remains and may increase in the case of mine drowning. As several mines will be closed during the next few years, the problems of drowned waste (which were not subjects of this study) are going to be more actual than before: increasing underground water level, pollution of underground water, formation of technogenic water sources, overflooding of reclaimed areas, etc. (author)
The 'shale gas revolution' - responsible for a huge increase in unconventional gas production in the US over the last couple of years - is creating huge investor uncertainties for international gas markets and renewables and could result in serious gas shortages in 10 years time. This report casts serious doubt over industry confidence in the 'revolution', questioning whether it can spread beyond the US, or indeed be maintained within it, as environmental concerns, high depletion rates and the fear that US circumstances may be impossible to replicate elsewhere, come to the fore. Investor uncertainty will reduce investment in future gas supplies to lower levels than would have happened had the 'shale gas revolution' not hit the headlines. While the markets will eventually solve this problem, rising gas demand and the long lead-in-times on most gas projects are likely to inflict high prices on consumers in the medium term. The uncertainties created by the 'shale gas revolution' are also likely to compound existing investor uncertainty in renewables for power generation in the aftermath of Copenhagen. The serious possibility of cheap, relatively clean gas may threaten investment in more expensive lower carbon technologies.
Dan S. Rickman; Wang, Hongbo; Winters, John V
Using the Synthetic Control Method (SCM) and a novel method for measuring changes in educational attainment we examine the link between educational attainment and shale oil and gas extraction for the states of Montana, North Dakota, and West Virginia. The three states examined are economically-small, relatively more rural, and have high levels of shale oil and gas reserves. They also are varied in that West Virginia is intensive in shale gas extraction, while the other two are intensive in sh...
Klimenko, Vladimir; Tereshin, Alexey
In recent years one has witnessed an increasing interest in the shale gas issue with the greatest level of concern at different levels of society, up to the political ones. The present article analyzes data on the shale gas resources, both worldwide and in certain regions. The authors assess the possibilities of shale gas production and prospects of its use to substitute other types of energy. They also present the model of atmosphere and climate change due to emissions from additional unconv...
Olmstead, Sheila M.; Lucija A. Muehlenbachs; Shih, Jhih-Shyang; Chu, Ziyan; Alan J. Krupnick
Concern has been raised in the scientific literature about the environmental implications of extracting natural gas from deep shale formations, and published studies suggest that shale gas development may affect local groundwater quality. The potential for surface water quality degradation has been discussed in prior work, although no empirical analysis of this issue has been published. The potential for large-scale surface water quality degradation has affected regulatory approaches to shale...
Peter A. O’Connor; Cutler J. Cleveland
The two methods of processing synthetic crude from organic marlstone in demonstration or small-scale commercial status in the U.S. are in situ extraction and surface retorting. The considerable uncertainty surrounding the technological characterization, resource characterization, and choice of the system boundary for oil shale operations indicate that oil shale is only a minor net energy producer if one includes internal energy (energy in the shale that is used during the process) as an energ...
Renjin Sun; Zhenjie Wang
The great success of US commercial shale gas exploitation stimulates the shale gas development in China, subsequently, the corresponding supporting policies were issued in the 12th Five-Year Plan. But from the experience in the US shale gas development, we know that the resulted environmental threats are always an unavoidable issue, but no uniform and standard evaluation system has yet been set up in China. The comprehensive environment refers to the combination of natural ecological environm...
Some basic data about the occurrence of pollutants in the flue gases of oil- shale power plants at the present time are given. Future prospects are discussed and specific requirements and recommendations concerning flue gas purification systems of oil-shale power plants are proposed. At the moment two different flue gas desulphurisation systems - a wet and dry one, are being designed, which should be a start up in introducing respective systems for oil-shale power plants. (author)
In Estonia, reforesting has been considered to be the most sustainable way of restoring the productivity of land damaged by oil shale mining. As distinct reforestation alternatives give different results, three alternative ways of reforesting oil shale opencasts are compared: natural succession, and planting seedlings of either Scots pine or black alder. The present research shows that the use of unassisted natural succession is the most sustainable way of reforesting oil shale opencasts
Obiang Bindang, Segismundo Crispin
Según la Comisión Europea el gas jugará un papel importante en la política energética de la Unión Europea, puesto que no sólo es el combustible fósil más limpio disponible, sino el más abundante en Europa y en otros continentes. En España con alta tasa de importación de gas, componente vital en el mix energético. La mayoría de los proyectos de shale gas se han llevado a cabo en el norte de España, pero en este proyecto se tiene como objetivo analizar las posibilidades de shale gas y shale ...
Kort, E. A.; Smith, M. L.; Murray, L. T.; Gvakharia, A.; Brandt, A. R.; Peischl, J.; Ryerson, T. B.; Sweeney, C.; Travis, K.
Ethane is the second most abundant atmospheric hydrocarbon, exerts a strong influence on tropospheric ozone, and reduces the atmosphere's oxidative capacity. Global observations showed declining ethane abundances from 1984 to 2010, while a regional measurement indicated increasing levels since 2009, with the reason for this subject to speculation. The Bakken shale is an oil and gas-producing formation centered in North Dakota that experienced a rapid increase in production beginning in 2010. We use airborne data collected over the North Dakota portion of the Bakken shale in 2014 to calculate ethane emissions of 0.23 ± 0.07 (2σ) Tg/yr, equivalent to 1-3% of total global sources. Emissions of this magnitude impact air quality via concurrent increases in tropospheric ozone. This recently developed large ethane source from one location illustrates the key role of shale oil and gas production in rising global ethane levels.
Kort, E. A.; Smith, M. L.; Murray, L. T.; Gvakharia, A.; Brandt, A. R.; Peischl, J.; Ryerson, T. B.; Sweeney, C.; Travis, K.
Ethane is the second most abundant atmospheric hydrocarbon, exerts a strong influence on tropospheric ozone, and reduces the atmosphere's oxidative capacity. Global observations showed declining ethane abundances from 1984 to 2010, while a regional measurement indicated increasing levels since 2009, with the reason for this subject to speculation. The Bakken shale is an oil and gas-producing formation centered in North Dakota that experienced a rapid increase in production beginning in 2010. We use airborne data collected over the North Dakota portion of the Bakken shale in 2014 to calculate ethane emissions of 0.23 +/- 0.07 (2 sigma) Tg/yr, equivalent to 1-3% of total global sources. Emissions of this magnitude impact air quality via concurrent increases in tropospheric ozone. This recently developed large ethane source from one location illustrates the key role of shale oil and gas production in rising global ethane levels.
Schulz, Hans-Martin; Bernard, Sylvain; Horsfield, Brian; Krüger, Martin; Littke, Ralf; di primio, Rolando
The Early Toarcian Posidonia Shale is a proven hydrocarbon source rock which was deposited in a shallow epicontinental basin. In southern Germany, Tethyan warm-water influences from the south led to carbonate sedimentation, whereas cold-water influxes from the north controlled siliciclastic sedimentation in the northwestern parts of Germany and the Netherlands. Restricted sea-floor circulation and organic matter preservation are considered to be the consequence of an oceanic anoxic event. In contrast, non-marine conditions led to sedimentation of coarser grained sediments under progressively terrestrial conditions in northeastern Germany The present-day distribution of Posidonia Shale in northern Germany is restricted to the centres of rift basins that formed in the Late Jurassic (e.g., Lower Saxony Basin and Dogger Troughs like the West and East Holstein Troughs) as a result of erosion on the basin margins and bounding highs. The source rock characteristics are in part dependent on grain size as the Posidonia Shale in eastern Germany is referred to as a mixed to non-source rock facies. In the study area, the TOC content and the organic matter quality vary vertically and laterally, likely as a consequence of a rising sea level during the Toarcian. Here we present and compare data of whole Posidonia Shale sections, investigating these variations and highlighting the variability of Posidonia Shale depositional system. During all phases of burial, gas was generated in the Posidonia Shale. Low sedimentation rates led to diffusion of early diagenetically formed biogenic methane. Isochronously formed diagenetic carbonates tightened the matrix and increased brittleness. Thermogenic gas generation occurred in wide areas of Lower Saxony as well as in Schleswig Holstein. Biogenic methane gas can still be formed today in Posidonia Shale at shallow depth in areas which were covered by Pleistocene glaciers. Submicrometric interparticle pores predominate in immature samples. At
The objective of this report is to perform a critical review of the data on the mineral and chemical alterations that occur during diagenesis and low-grade metamorphism of shale and other clay-rich rocks - conditions similar to those expected from emplacement of heat-producing radioactive waste in a geologic repository. The conclusions drawn in this document are that the following type of alterations could occur: smectite alteration, ion mobilization, illitic shales, kaolinite reactions, chlorite reactions, organic reactions, paleotemperatures, low temperature shales, high temperature shales, and phase equilibrium changes
KAVALOV Boyan; PELLETIER NATHANIEL
The purpose of this study is to provide an overview of shale gas development in the USA and to assess the implications of findings with regard to the prospects for shale gas development in the EU by 2020-2030. Particular emphasis is placed on the environmental and social aspects of market-scale extraction of shale gas. Any purely technological, techno-economic and regulatory aspects of shale gas exploitation are beyond the scope of this study. Other European Commission services, such as DG fo...
Estonia is still the world leader in utilization of oil shale. Enefit has cooperated with Outotec to develop a new generation of solid heat carrier technology - Enefit280, which is more efficient, environmentally friendlier and has higher unit capacity. Breakeven price of oil produced in Enefit280 process is competitive with conventional oils. The new technology has advantages that allow easy adaptation to other oil shales around the world. Hydrotreated shale oil liquids have similar properties to crude oil cuts. Design for a shale oil hydrotreater unit can use process concepts, hardware components, and catalysts commercially proven in petroleum refining services.
The purpose of this report is to discuss the geology and resources of some selected deposits of oil shale in varied geologic settings from different pars of the world. Total resources of a selected group of oil shale on origining 33 countries is estimated at 411 billion tons in-place shale oil which is equivalent to 2.9 trillion U.S. barrels of shale oil. To what extent an oil shale resource can be commercially developed depends upon many factors. The most important factor that will determine the large-scale development of an oil shale industry is the price of petroleum. Some countries having good-quality oil shale but lacking petroleum and/or coal resources will continue to mine oil shale for transportation fuels, petrochemicals, fuel for electric power plants, building materials, and other byproducts. However, their oil shale industries face imposing challenges from cheaper resources of petroleum and coal as well as being a significant source of air and water pollution
The increase in the exploration and extraction of hydrocarbons, especially natural gas, from shale formations has been facilitated by advents in horizontal drilling and hydraulic fracturing technologies. Shale energy resources are very promising as an abundant energy source, though environmental challenges exist with their development, including potential adverse impacts to water quality. The well drilling and construction process itself has the potential to impact groundwater quality, however if proper protocols are followed and well integrity is established then impacts such as methane migration or drilling fluids releases can be minimized. Once a shale well has been drilled and hydraulically fractured, approximately 10-50% of the volume of injected fluids (flowback fluids) may flow out of the well initially with continued generation of fluids (produced fluids) throughout the well's productive life. Produced fluid TDS concentrations often exceed 200,000 mg/L, with elevated levels of strontium (Sr), bromide (Br), sodium (Na), calcium (Ca), barium (Ba), chloride (Cl), radionuclides originating from the shale formation as well as fracturing additives. Storing, managing and properly disposisng of these fluids is critical to ensure water resources are not impacted by unintended releases. The most recent data in Pennsylvania suggests an estimated 85% of the produced fluids were being recycled for hydraulic fracturing operations, while many other states reuse less than 50% of these fluids and rely moreso on underground injection wells for disposal. Over the last few years there has been a shift to reuse more produced fluids during well fracturing operations in shale plays around the U.S., which has a combination of economic, regulatory, environmental, and technological drivers. The reuse of water is cost-competitive with sourcing of fresh water and disposal of flowback, especially when considering the costs of advanced treatment to or disposal well injection and lessens
José Francisco Longoria Treviño
El shale gas tiene su origen en la acumulación de materia orgánica en cuencas marinas. En Norteamérica el gas de lutita (shale gas) es una fuente emergente de gas natural de bajo costo. El gas natural es una fuente de energía abundante y relativamente limpia al quemarse. Se ha convertido en un combustible popular tanto para aplicaciones residenciales como industriales. De acuerdo con los datos recientes se estima que el suministro de gas natural derivado de yacimientos no convencionales (g...
Quan Gao; Junliang Tao; Jianying Hu; Xiong (Bill) Yu
Shale gas is becoming an important energy source worldwide. The geomechanical properties of shale rocks can have a major impact on the efficiency of shale gas exploration. This paper studied the mineralogical and mechanical characteristics of a typical gas shale in Ohio, USA. Scanning electron microscope (SEM) with energy dispersive X-ray (EDX) analyses was employed to measure the microstructure and material composition of the shale rock. The anisotropic behaviors of shale rock, including com...
Akselsen, Anniken Berg
The emergence of hydrocarbon energy extracted from shale has been nicknamed the Shale Gas Revolution , due to its implications for the American society, geo-politics and economy. This thesis will explain how the economic growth shale gas production in Pennsylvania so far has contributed to can be maintained, also for the future, when shale gas is no longer produced or depleted. By focusing on Pennsylvania, which has the nation s highest shale gas production growth rate, this thesis will exam...
The energy crisis affects all countries in the world. Considering the price scenarios, many countries in Africa have begun to explore various energy resources. Ethiopia is one of the countries that depend upon imported petroleum products. To overcome this problem, geological studies suggest a significant occurrence of oil shale deposits in Ethiopia. The Inter-Trappean oil shale-bearing sediments are widely distributed on the South-Western Plateau of Ethiopia in the Delbi-Moye, Lalo-Sapo, Sola, Gojeb-Chida and Yayu Basins. The oil shale-bearing sediments were deposited in fluviatile and lacustrine environments. The oil shales contain mixtures of algal, herbaceous and higher plant taxa. They are dominated by algal-derived liptinite with minor amounts of vitrinite and inertinite. The algal remains belong to Botryococcus and Pediastrum. Laboratory results confirm that the Ethiopian oil shales are dominated by long-chain aliphatic hydrocarbons and have a low sulphur content. Type-II and Type-I kerogen dominated the studied oil shales. Type-II and Type-I are good source rocks for oil and gas generation. Hydrogen index versus Tmax value plots indicated that most of the oil shale samples fall within the immature-early mature stage for hydrocarbon generation, consistent with the Ro values that range from 0.3% to 0.64%. Pyrolysis data of the oil shales sensu stricto indicate excellent source rocks with up to 61.2% TOC values. Calorific value ranges from 400 to 6165 cal/g. Palynological studies confirmed that the oil shale-bearing sediments of Ethiopia range from Eocene to Miocene in age. A total of about 253,000,000 ton of oil shale is registered in the country. Oil shale deposits in Ethiopia can be used for production of oil and gas.
Chappell, W R
The purpose of this research program is to understand the potential impact of an oil shale industry on environmental levels of trace contaminants in the region. The program involves a comprehensive study of the sources, release mechanisms, transport, fate, and effects of toxic trace chemicals, principally the trace elements, in an oil shale industry. The overall objective of the program is to evaluate the environmental and health consequences of the release of toxic trace elements by shale and oil production and use. The baseline geochemical survey shows that stable trace elements maps can be constructed for numerous elements and that the trends observed are related to geologic and climatic factors. Shale retorted by above-ground processes tends to be very homogeneous (both in space and in time) in trace element content. Leachate studies show that significant amounts of B, F, and Mo are released from retorted shales and while B and Mo are rapidly flushed out, F is not. On the other hand, As, Se, and most other trace elements are not present in significant quantities. Significant amounts of F and B are also found in leachates of raw shales. Very large concentrations of reduced sulfur species are found in leachates of processed shale. Very high levels of B and Mo are taken up in some plants growing on processed shale with and without soil cover. There is a tendency for some trace elements to associate with specific organic fractions, indicating that organic chelation or complexation may play an important role. Many of the so-called standard methods for analyzing trace elements in oil shale-related materials are inadequate. A sampling manual is being written for the environmental scientist and practicing engineer. A new combination of methods is developed for separating the minerals in oil shale into different density fractions. Microbial investigations have tentatively identified the existence of thiobacilli in oil shale materials such as leachates. (DC)
Zhang, Xiaodong; Sun, Alexander Y; Duncan, Ian J
This work presents an optimization framework for evaluating different wastewater treatment/disposal options for water management during hydraulic fracturing (HF) operations. This framework takes into account both cost-effectiveness and system uncertainty. HF has enabled rapid development of shale gas resources. However, wastewater management has been one of the most contentious and widely publicized issues in shale gas production. The flowback and produced water (known as FP water) generated by HF may pose a serious risk to the surrounding environment and public health because this wastewater usually contains many toxic chemicals and high levels of total dissolved solids (TDS). Various treatment/disposal options are available for FP water management, such as underground injection, hazardous wastewater treatment plants, and/or reuse. In order to cost-effectively plan FP water management practices, including allocating FP water to different options and planning treatment facility capacity expansion, an optimization model named UO-FPW is developed in this study. The UO-FPW model can handle the uncertain information expressed in the form of fuzzy membership functions and probability density functions in the modeling parameters. The UO-FPW model is applied to a representative hypothetical case study to demonstrate its applicability in practice. The modeling results reflect the tradeoffs between economic objective (i.e., minimizing total-system cost) and system reliability (i.e., risk of violating fuzzy and/or random constraints, and meeting FP water treatment/disposal requirements). Using the developed optimization model, decision makers can make and adjust appropriate FP water management strategies through refining the values of feasibility degrees for fuzzy constraints and the probability levels for random constraints if the solutions are not satisfactory. The optimization model can be easily integrated into decision support systems for shale oil/gas lifecycle
Full Text Available Natural gas will continue to play a key role in the EU’s energy mix in the coming years, with unconventional gas’ role increasing in importance as new resources are exploited worldwide. As far as Europe’s own shale gas resources are concerned, it is especially the public’s perception and level of acceptance that will make or break shale gas in the near-term. Both the pros and cons need to be discussed based on factual argument rather than speculation. Research organizations such as ours (GFZ German Research Centre for Geosciences have an active and defining role to play in remedying this deficiency. As far as science and technology developments are concerned, the project “Gas Shales in Europe” (GASH and the shale gas activities of “GeoEnergie” (GeoEn are the first major initiatives in Europe focused on shale gas. Basic and applied geoscientific research is conducted to understand the fundamental nature and interdependencies of the processes leading to shale gas formation. When it comes to knowledge transfer, the perceived and real risks associated with shale gas exploitation need immediate evaluation in Europe using scientific analysis. To proactively target these issues, the GFZ and partners are launching the European sustainable Operating Practices (E-SOP Initiative for Unconventional Resources. The web-based Shale Gas Information Platform (SHIP brings these issues into the public domain.
Data are presented in these appendices on the marketing and economic potential for soda ash, aluminia, and nahcolite as by-products of shale oil production. Appendices 1 and 2 contain data on the estimated capital and operating cost of an oil shales/mineral co-products recovery facility. Appendix 3 contains the marketing research data.
... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Devonian shale wells in Michigan. 270.306 Section 270.306 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY... Devonian Age Antrim shale through: (i) A well the surface drilling of which began after December 31,...
The article describes the fly ash and shale fired brick production line with annual output of 1250 million bricks, designed by Xi'an Research and Design Institute of Wall and Roof Material, commissioned by QinDian Building Material Subcompany, and set an example for using fly ash and shale in China.
Attia, A; Vorobiev, O; Walsh, S
The purpose of this report is to present the implementation of a shale model in the Geodyn code, based on published rock material models and properties that can help a petroleum engineer in his design of various strategies for oil/gas recovery from shale rock formation.
Birdwell, Justin E.; Washburn, Kathryn E.
Low-field nuclear magnetic resonance (NMR) relaxometry has been used to provide insight into shale composition by separating relaxation responses from the various hydrogen-bearing phases present in shales in a noninvasive way. Previous low-field NMR work using solid-echo methods provided qualitative information on organic constituents associated with raw and pyrolyzed oil shale samples, but uncertainty in the interpretation of longitudinal-transverse (T1–T2) relaxometry correlation results indicated further study was required. Qualitative confirmation of peaks attributed to kerogen in oil shale was achieved by comparing T1–T2 correlation measurements made on oil shale samples to measurements made on kerogen isolated from those shales. Quantitative relationships between T1–T2 correlation data and organic geochemical properties of raw and pyrolyzed oil shales were determined using partial least-squares regression (PLSR). Relaxometry results were also compared to infrared spectra, and the results not only provided further confidence in the organic matter peak interpretations but also confirmed attribution of T1–T2 peaks to clay hydroxyls. In addition, PLSR analysis was applied to correlate relaxometry data to trace element concentrations with good success. The results of this work show that NMR relaxometry measurements using the solid-echo approach produce T1–T2 peak distributions that correlate well with geochemical properties of raw and pyrolyzed oil shales.
Oil shale mining like every kind of exploitation of mineral resources imparts a variety of impacts on the environment. One group of factors has a temporary impact during the mining activities only, another group of factors leaves its footprints in nature for a long time. Geological conditions, mining methods underground or surface mining, roof control methods and methods of reclamation determine the variety of landforms and their parameters in post mining landscape. Long-time ecological observations and changing economical conditions can influence the current attitudes and criteria of assessments of the environmental impact caused by mining. (author)
Lapidus, A.; Avakyan, T. [I.M. Gubkin Russian State Univ. of Oil and Gas, Moscow (Russian Federation); Strizhakova, Yu. [Samara State Univ. (Russian Federation)
Nowadays, the problem of complex usage of solid fossil fuels as raw materials for obtaining of motor fuels and chemical products is becoming increasingly important. A one of possible solutions of the problem is their gasification with further processing of gaseous and liquid products. In this work we have investigated the process of thermal and catalytic gasification of Baltic and Kashpir oil-shales. We have shown that, as compared with non-catalytic process, using of nickel catalyst in the reaction increases the yield of gas, as well as hydrogen content in it, and decreases the amount of liquid products. (orig.)
This bibliographical note presents a book in which the author first proposes a presentation and an explanation of the main technical and geological notions related to shale gases. He describes the noticed ecological impacts of shale gas exploitation in North America, and discusses to which extent it is possible to deduce the impacts shale gases would have in France with its different geological, legal, industrial, and culture context. He discusses the economic challenges, i.e. what has been the impact of shale gases on the American economy, and what it could be in the French context. Then, the author proposes an analysis of the French situation with respect to shale gases: national geological reserves, usage opportunities, legal and political context
Marble, B. [Hallwood Petroleum, Dallas, TX (United States)
This presentation provided details of the underlying geology of the Fayetteville shale gas plays and discussed engineering strategies used to improve productivity. Like the Barnett shale gas play, the Fayetteville play is comprised of Mississippian shale, and contains both free and adsorbed gas. Operators in Fayetteville use seismic data in order to avoid faults in the play, which has large variations in structure and depth over short distances. A typical well is drilled in 40 days. Microseismic aids will be used to plan future horizontal development and for 3-dimensional fracture analysis. Multiple short wings are used to create more concentrated frac patterns. However, once broken, the laminated shales will not re-align when frac pressure is released. The high clay content of the shale reduces frac efficiency. It was concluded that modified slick water fracs are now being used at the play along with air drilling to reduce costs, and straighten holes. tabs., figs.
This study examines the potential for separating, upgrading and marketing sodium mineral co-products together with shale oil production. The co-products investigated are soda ash and alumina which are derived from the minerals nahcolite and dawsonite. Five cases were selected to reflect the variance in mineral and shale oil content in the identified resource. In the five cases examined, oil content of the shale was varied from 20 to 30 gallons per ton. Two sizes of facilities were analyzed for each resource case to determine economies of scale between a 15,000 barrel per day demonstration unit and a 50,000 barrel per day full sized plant. Three separate pieces of analysis were conducted in this study: analysis of manufacturing costs for shale oil and co-products; projection of potential world markets for alumina, soda ash, and nahcolite; and determination of economic viability and market potential for shale co-products.
Villamor Lora, R.; Ghazanfari, E.
The mechanical properties of shale are demanding parameters for a number of engineering and geomechanical purposes. Borehole stability modeling, geophysics, shale oil and shale gas reservoirs, and underground storage of CO2 in shale formations are some of these potential applications to name a few. The growing interest in these reservoirs, as a source for hydrocarbons production, has resulted in an increasing demand for fundamental rock property data. These rocks are known to be non-linear materials. There are many factors, including induced cracks and their orientation, partial saturation, material heterogeneity and anisotropy, plasticity, strain rate, and temperature that may have an impact on the geomechanical behaviour of these shales.Experimental results and theoretical considerations have shown that the elastic moduli are not single-value, well-defined parameters for a given rock. Finding suitable values for these parameters is of vital importance in many geomechanical applications. In this study, shale heterogeneity and its geomechanical properties are explored through an extensive laboratory experimental program. A series of hydrostatic and triaxial tests were performed in order to evaluate the elasticity, viscoplasticity, yielding and failure response of Marcellus shale samples as a function of pressure and temperature. Additional characterization includes mineralogy, porosity, and permeability measurements. The shale samples were taken from a Marcellus outcrop at State Game Lands 252, located in Lycoming and Union counties, Allenwood, Pennsylvania. Laboratory experiments have shown that creep behaviour is highly sensitive to temperature. Furthermore, the non-linear nature of these rocks reveals interesting behaviour of the elastic moduli highly dependent on stress history of the rock. Results from cyclic triaxial tests point out the different behaviour between 1st-loading and unloading-reloading cycles. Experimental results of these Marcellus shales are
Scanning and transmission electron microscopy, synchrotron X-ray diffraction, microtomography and ultrasonic velocity measurements were used to characterize microstructures and anisotropy of three deeply buried Qusaiba shales from the Rub\\'al-Khali basin, Saudi Arabia. Kaolinite, illite-smectite, illite-mica and chlorite show strong preferred orientation with (001) pole figure maxima perpendicular to the bedding plane ranging from 2.4-6.8 multiples of a random distribution (m.r.d.). Quartz, feldspars and pyrite crystals have a random orientation distribution. Elastic properties of the polyphase aggregate are calculated by averaging the single crystal elastic properties over the orientation distribution, assuming a nonporous material. The average calculated bulk P-wave velocities are 6.2 km/s (maximum) and 5.5 km/s (minimum), resulting in a P-wave anisotropy of 12%. The calculated velocities are compared with those determined from ultrasonic velocity measurements on a similar sample. In the ultrasonic experiment, which measures the effects of the shale matrix as well as the effects of porosity, velocities are smaller (P-wave maximum 5.3 km/s and minimum 4.1 km/s). The difference between calculated and measured velocities is attributed to the effects of anisotropic pore structure and to microfractures present in the sample, which have not been taken into account in the matrix averaging. © 2011 European Association of Geoscientists & Engineers.
Mercer, B.W.; Wakamiya, W.; Bell, N.E.; Mason, M.J.; Spencer, R.R.; English, C.J.; Riley, R.G.
This report summarizes the results of studies conducted at Pacific Northwest Laboratory from 1976 to 1982 on environmental control technology for shale oil wastewaters. Experimental studies conducted during the course of the program were focused largely on the treatment and disposal of retort water, particularly water produced by in situ retorting of oil shale. Alternative methods were evaluated for the treatment and disposal of retort water and minewater. Treatment and disposal processes evaluated for retort water include evaporation for separation of water from both inorganic and organic pollutants; steam stripping for ammonia and volatile organics removal; activated sludge and anaerobic digestion for removal of biodegradable organics and other oxidizable substances; carbon adsorption for removal of nonbiodegradable organics; chemical coagulation for removal of suspended matter and heavy metals; wet air oxidation and solvent extraction for removal of organics; and land disposal and underground injection for disposal of retort water. Methods for the treatment of minewater include chemical processing and ion exchange for fluoride and boron removal. Preliminary cost estimates are given for several retort water treatment processes.
Kang, Yili; Chen, Mingjun; Li, Xiangchen; You, Lijun; Yang, Bin
Gas flow mechanisms in shale are urgent to clarify due to the complicated pore structure and low permeability. Core flow experiments were conducted under reservoir net confining stress with samples from the Longmaxi Shale to investigate the characteristics of nonlinear gas flow. Meanwhile, microstructure analyses and gas adsorption experiments are implemented. Experimental results indicate that non-Darcy flow in shale is remarkable and it has a close relationship with pore pressure. It is found that type of gas has a significant influence on permeability measurement and methane is chosen in this work to study the shale gas flow. Gas slippage effect and minimum threshold pressure gradient weaken with the increasing backpressure. It is demonstrated that gas flow regime would be either slip flow or transition flow with certain pore pressure and permeability. Experimental data computations and microstructure analyses confirm that hydraulic radius of flow tubes in shale are mostly less than 100 nm, indicating that there is no micron scale pore or throat which mainly contributes to flow. The results are significant for the study of gas flow in shale, and are beneficial for laboratory investigation of shale permeability.
Full Text Available The great success of US commercial shale gas exploitation stimulates the shale gas development in China, subsequently, the corresponding supporting policies were issued in the 12th Five-Year Plan. But from the experience in the US shale gas development, we know that the resulted environmental threats are always an unavoidable issue, but no uniform and standard evaluation system has yet been set up in China. The comprehensive environment refers to the combination of natural ecological environment and external macro-environment. In view of this, we conducted a series of studies on how to set up a comprehensive environmental impact assessment system as well as the related evaluation methodology and models. First, we made an in-depth investigation into shale gas development procedures and any possible environmental impacts, and then compared, screened and modified environmental impact assessment methods for shale gas development. Also, we established an evaluating system and assessment models according to different status of the above two types of environment: the correlation matrix method was employed to assess the impacts on natural ecological environment and the optimization distance method was modified to evaluate the impacts on external macro-environment. Finally, we substitute the two subindexes into the comprehensive environmental impact assessment model and achieved the final numerical result of environmental impact assessment. This model can be used to evaluate if a shale gas project has any impact on environment, compare the impacts before and after a shale gas development project, or the impacts of different projects.
This study estimates the life cycle greenhouse gas (GHG) emissions from the production of Marcellus shale natural gas and compares its emissions with national average US natural gas emissions produced in the year 2008, prior to any significant Marcellus shale development. We estimate that the development and completion of a typical Marcellus shale well results in roughly 5500 t of carbon dioxide equivalent emissions or about 1.8 g CO2e/MJ of gas produced, assuming conservative estimates of the production lifetime of a typical well. This represents an 11% increase in GHG emissions relative to average domestic gas (excluding combustion) and a 3% increase relative to the life cycle emissions when combustion is included. The life cycle GHG emissions of Marcellus shale natural gas are estimated to be 63-75 g CO2e/MJ of gas produced with an average of 68 g CO2e/MJ of gas produced. Marcellus shale natural gas GHG emissions are comparable to those of imported liquefied natural gas. Natural gas from the Marcellus shale has generally lower life cycle GHG emissions than coal for production of electricity in the absence of any effective carbon capture and storage processes, by 20-50% depending upon plant efficiencies and natural gas emissions variability. There is significant uncertainty in our Marcellus shale GHG emission estimates due to eventual production volumes and variability in flaring, construction and transportation.
Estimates of greenhouse gas (GHG) emissions from shale gas production and use are controversial. Here we assess the level of GHG emissions from shale gas well hydraulic fracturing operations in the United States during 2010. Data from each of the approximately 4000 horizontal shale gas wells brought online that year are used to show that about 900 Gg CH4 of potential fugitive emissions were generated by these operations, or 228 Mg CH4 per well—a figure inappropriately used in analyses of the GHG impact of shale gas. In fact, along with simply venting gas produced during the completion of shale gas wells, two additional techniques are widely used to handle these potential emissions: gas flaring and reduced emission ‘green’ completions. The use of flaring and reduced emission completions reduce the levels of actual fugitive emissions from shale well completion operations to about 216 Gg CH4, or 50 Mg CH4 per well, a release substantially lower than several widely quoted estimates. Although fugitive emissions from the overall natural gas sector are a proper concern, it is incorrect to suggest that shale gas-related hydraulic fracturing has substantially altered the overall GHG intensity of natural gas production. (letter)
Methane from oil shale can potentially provide a significant contribution to natural gas industry, and it may be possible to increase and continue methane production by artificially enhancing methanogenic activity through the addition of various substrate and nutrient treatments. Western Research Institute in conjunction with Pick & Shovel Inc. and the U.S. Department of Energy conducted microcosm and scaled-up reactor studies to investigate the feasibility and optimization of biogenic methane production from oil shale. The microcosm study involving crushed oil shale showed the highest yield of methane was produced from oil shale pretreated with a basic solution and treated with nutrients. Incubation at 30 C, which is the estimated temperature in the subsurface where the oil shale originated, caused and increase in methane production. The methane production eventually decreased when pH of the system was above 9.00. In the scaled-up reactor study, pretreatment of the oil shale with a basic solution, nutrient enhancements, incubation at 30 C, and maintaining pH at circumneutral levels yielded the highest rate of biogenic methane production. From this study, the annual biogenic methane production rate was determined to be as high as 6042 cu. ft/ton oil shale.
Highlights: ► Economic feasibility of five European shale gas plays is assessed. ► Polish and Austrian shale plays appear profitable for P90 assessment criterion. ► Posidonia (Germany), Alum (Sweden) and a Turkish shale play below the hurdle rate. ► A 10% improvement of the IRR by sweet spot targeting makes all plays profitable. - Abstract: This study evaluates the economic feasibility of five emergent shale gas plays on the European Continent. Each play is assessed using a uniform field development plan with 100 wells drilled at a rate of 10 wells/year in the first decade. The gas production from the realized wells is monitored over a 25 year life cycle. Discounted cash flow models are used to establish for each shale field the estimated ultimate recovery (EUR) that must be realized, using current technology cost, to achieve a profit. Our analyses of internal rates of return (IRR) and net present values (NPVs) indicate that the Polish and Austrian shale plays are the more robust, and appear profitable when the strict P90 assessment criterion is applied. In contrast, the Posidonia (Germany), Alum (Sweden) and a Turkish shale play assessed all have negative discounted cumulative cash flows for P90 wells, which puts these plays below the hurdle rate. The IRR for P90 wells is about 5% for all three plays, which suggests that a 10% improvement of the IRR by sweet spot targeting may lift these shale plays above the hurdle rate. Well productivity estimates will become better constrained over time as geological uncertainty is reduced and as technology improves during the progressive development of the shale gas fields
de Nevers, N.; Eckhoff, D.; Swanson, S.; Glenne, B.; Wagner, F.
The environmental control technology proposed in the various oil shale projects which are under development are examined. The technologies for control of air pollution, water pollution, and for the disposal, stabilization, and vegetation of the processed shale were thoroughly investigated. Although some difficulties may be encountered in any of these undertakings, it seems clear that the air and water pollution problems can be solved to meet any applicable standard. There are no published national standards against which to judge the stabilization and vegetation of the processed shale. However, based on the goal of producing an environmentally and aesthetically acceptable finished processed shale pile, it seems probable that this can be accomplished. It is concluded that the environmental control technology is available to meet all current legal requirements. This was not the case before Colorado changed their applicable Air Pollution regulations in August of 1977; the previous ones for the oil shale region were sufficiently stringent to have caused a problem for the current stage of oil shale development. Similarly, the federal air-quality, non-deterioration regulations could be interpreted in the future in ways which would be difficult for the oil shale industry to comply with. The Utah water-quality, non-deterioration regulations could also be a problem. Thus, the only specific regulations which may be a problem are the non-deterioration parts of air and water quality regulations. The unresolved areas of environmental concern with oil shale processing are mostly for the problems not covered by existing environmental law, e.g., trace metals, polynuclear organics, ground water-quality changes, etc. These may be problems, but no evidence is yet available that these problems will prevent the successful commercialization of oil shale production.
After 20 years at different positions in the gas sector, from the policy side to trading floors, the author gives an overview of the major gas issues and elaborate on the consequences of the US shale gas revolution. The first part of the book provides basic knowledge and gives needed tools to better understand this industry, that often stands, in sandwich, between upstream oil and utilities. After extensive research, publication and teaching, the author shares his insights on fundamental issues all along the gas chain and explains the price mechanisms ranging from oil-indexing to spot. The second part looks into the future of worldwide gas balance. To supply growing markets, the major resource holder, Russia, is now in direct competition with the major gas producer, the US. China has the potential not only to select the winner but also to decide the pricing principle for all Asian buyers in 2020. As China is a new and growing gas importer and has a lower price tolerance than historical Asian buyers (Japan and South Korea), it is highly possible that, against basic geography, China selects waterborne US LNG vs. close Russian pipe gas, to achieve lower import price. Europe, so risk adverse that it won't be able to take any decision regarding shale gas production on this side of 2020, should see its power fading on the energy scene and would rely more on Russia. Gas geopolitics could tighten Russia stronghold on Europe, on one side, and create a flourishing North America-Asian trade... This book is accessible to all and will particularly interest readers seeking a global gas perspective where economics and geopolitics mix. It can be read as an economic novel where billions of $ are invested to shape tomorrow energy world or as a geopolitical thriller where Russia and the US compete to impose their respective agenda, leaving China to select the winner. Contents: 1. Basics. 2. Technicals. 3. Markets, prices and costs. 4. Policies. 5. Where is the future supply growth? 6
After 20 years at different positions in the gas sector, from the policy side to trading floors, the author gives an overview of the major gas issues and elaborate on the consequences of the US shale gas revolution. The first part of the book provides basic knowledge and gives needed tools to better understand this industry, that often stands, in sandwich, between upstream oil and utilities. After extensive research, publication and teaching, the author shares his insights on fundamental issues all along the gas chain and explains the price mechanisms ranging from oil-indexing to spot. The second part looks into the future of worldwide gas balance. To supply growing markets, the major resource holder, Russia, is now in direct competition with the major gas producer, the US. China has the potential not only to select the winner but also to decide the pricing principle for all Asian buyers in 2020. As China is a new and growing gas importer and has a lower price tolerance than historical Asian buyers (Japan and South Korea), it is highly possible that, against basic geography, China selects waterborne US LNG vs. close Russian pipe gas, to achieve lower import price. Europe, so risk adverse that it won't be able to take any decision regarding shale gas production on this side of 2020, should see its power fading on the energy scene and would rely more on Russia. Gas geopolitics could tighten Russia stronghold on Europe, on one side, and create a flourishing North America-Asian trade... This book is accessible to all and will particularly interest readers seeking a global gas perspective where economics and geopolitics mix. It can be read as an economic novel where billions of $ are invested to shape tomorrow energy world or as a geopolitical thriller where Russia and the US compete to impose their respective agenda, leaving China to select the winner. Contents: 1. Basics. 2. Technical aspects. 3. Markets, prices and costs. 4. Policies. 5. Where is the future supply
O'Sullivan, Francis Martin; Paltsev, Sergey
Estimates of greenhouse gas (GHG) emissions from shale gas production and use are controversial. Here we assess the level of GHG emissions from shale gas well hydraulic fracturing operations in the United States during 2010. Data from each of the approximately 4000 horizontal shale gas wells brought online that year are used to show that about 900 Gg CH[subscript 4] of potential fugitive emissions were generated by these operations, or 228 Mg CH[subscript 4] per well—a figure inappropriately ...
Neuzil, Christopher E.
Toss a dart at a map of the United States and, more often than not, it will land where shale can be found underground. A drab, relatively featureless sedimentary rock that historically attracted little interest, shale (as used here, the term includes clay and a range of clay-rich rocks) is entering Americans’ consciousness as a new source of gas and oil. But shale may also offer something entirely different—the ability to safely and permanently house high-level nuclear waste.
Shock waves produced by planar impact of thin plates onto samples of oil shale are monitored with time-resolved velocity interferometer diagnostics. Peak shock stresses are below the Hugoniot elastic limit. Stress wave measurements at successive sample thickness are analysed to determine the experimental shock energy attenuation with propagation distance. Shock attenuation is attributed to stress wave scattering at planes of oil shale kerogen within the shale matrix. Wave scattering from planar defects are evaluated from a shock physics perspective and a scattering model is constructed that sensibly reproduces the experimental observation of shock energy attenuation.
José Francisco Longoria Treviño
Full Text Available El shale gas tiene su origen en la acumulación de materia orgánica en cuencas marinas. En Norteamérica el gas de lutita (shale gas es una fuente emergente de gas natural de bajo costo. El gas natural es una fuente de energía abundante y relativamente limpia al quemarse. Se ha convertido en un combustible popular tanto para aplicaciones residenciales como industriales. De acuerdo con los datos recientes se estima que el suministro de gas natural derivado de yacimientos no convencionales (gas de lutita – shale gas durará más de 100 años. El gas natural ofrece un remplazo potencial para sustituir a los combustibles fósiles que producen gases de efecto invernadero y que en la actualidad se usan en la generación de energía, calefacción y transporte. Las emisiones de gas de efecto invernadero de la combustión de gas natural son aproximadamente 30% más limpias que aquellas que se derivan del aceite y 45% más limpias de las del carbón.
Chalmers, G.; Bustin, R.M. [British Columbia Univ., Vancouver, BC (Canada). Earth and Ocean Sciences
Geological controls on gas capacity and reservoir evaluation of lower Cretaceous shales in northeastern British Colombia were discussed. The location of the study area and a gas shale model were first introduced. The methodology was described with reference to rock evaluation analysis, high pressure methane sorption analysis, porosity, surface area of pores and x-ray diffraction (XRD) mineralogy. Data on total organic carbon (TOC) content was provided along with other types of geological controls such as kerogen type, maturity, mineralogy, surface area of pores, and moisture content. Clay mineralogy and data on pure clay sorption capacities were also presented. TOC content was found to be the primary control on sorption capacity. The presentation also discussed a regional reservoir evaluation of the organic-rich basal layer on the Garbutt-Moosebar-Wilrich-Buckinghorse formations. Isopach maps provided data on distribution of TOC and maturity; distribution of kerogen types and the oil/gas windows; and reservoir conditions of temperature and hydrostatic pressure. The effects of temperature on sorption capacity and porosity and total gas capacity were also presented in graphical format. Last, the presentation addressed exploration considerations for lower-K shales. tabs., figs.
In order to examine the biogenic nature of reduced carbon the carbon isotope ratios were determined in samples of different metablack shale and black shale deposits of the Precambrium of the mountains from Saxon Erzgebirge, Schwarzburger Sattel, from the crystalline zone of Ruhla, and also from Palaeozoic layers in the Saxon Erzgebirge Mountains and from its northern border zone. The investigated rocks vary from non- or weak-metamorphic shales, alum-shales and cherts via phyllits to the stronger metamorphic quarzites, gneisses and mica-schists. The isotopic analysis of the reduced carbon indicates, that the investigated metablack shales and black shales are remarkably enriched in 12C. This result tends to an organic nature of the reduced carbon of these rocks. The 21 samples of metablack shales of the Saxon Erzgebirge Mountains yielded a mean delta13C-value of -290/00. This corresponds with delta13C-values from other deposits of the earth's crust. The isotopic abundances don't show any dependence on the carbon amount, the rank of metamorphism or the age of the rock samples. (author)
The fact that USA have been reducing their oil dependence of one third within six years through the exploitation of shale gas and oil, and thus became almost self-sufficient as far as gas is concerned, and one of the most competitive country in the world again, will result in major geopolitical changes on a medium term: American imports from the Gulf will strongly decrease, the USA will become a gas exporter, Russia will have to look for other outlets, and so on. By proposing answers to twenty questions, the authors address the geopolitical, technical and social issues related to these evolutions. For example: are European source rocks as good as their American sisters? Will Europe be able to develop its resources at acceptable costs? What about the threats and issues perceived by some stakeholders like hydraulic fracturing, impact on water supply, risks of micro-earthquakes, or impact on surface environment in more urbanised environment than in the USA?
Proposed by the economic department of the French embassy in London, this report addresses the emergence of shale gas exploration/exploitation in the UK. It first evokes gas needs in the UK, briefly addresses the example of the USA, outlines that the development noticed in the USA is difficult to reproduce in Europe, and proposes an assessment of resources at the world level and at the British level. It discusses scientific challenges and recommendations as they are outlined in a public report made by the Royal Society and the Royal Academy of Engineering, and notably addresses issues related to water and fracking, to gas emissions and to seismic risks. The last part gives an overview of the British legal framework: creation of the Office for Unconventional Oil and Gas, existing regulations concerning water, air, seismic risks, and public commitment. It indicates the road-map given to involved companies
Physical adsorption refers to the trapping of fluid molecules at near liquid-like densities in the pores of a given adsorbent material. Fine-grained rocks, such as shales, contain a significant amount of nanopores that can significantly contribute to their storage capacity. As a matter of fact, the current ability to extract natural gas that is adsorbed in the rock's matrix is limited, and current technology focuses primarily on the free gas in the fractures (either natural or stimulated), thus leading to recovery efficiencies that are very low. Shales constitute also a great portion of so-called cap-rocks above potential CO2 sequestration sites; hereby, the adsorption process may limit the CO2 mobility within the cap-rock, thus minimizing the impact of leakage on the whole operation. Whether it is an unconventional reservoir or a cap-rock, understanding and quantifying the mechanisms of adsorption in these natural materials is key to improve the engineering design of subsurface operations. Results will be presented from a laboratory study that combines conventional techniques for the measurement of adsorption isotherms with novel methods that allows for the imaging of adsorption using x-rays. Various nanoporous materials are considered, thus including rocks, such as shales and coals, pure clay minerals (a major component in mudrocks) and engineered adsorbents with well-defined nanopore structures, such as zeolites. Supercritical CO2 adsorption isotherms have been measured with a Rubotherm Magnetic Suspension balance by covering the pressure range 0.1-20~MPa. A medical x-ray CT scanner has been used to identify three-dimensional patterns of the adsorption properties of a packed-bed of adsorbent, thus enabling to assess the spatial variability of the adsorption isotherm in heterogeneous materials. The data are analyzed by using thermodynamically rigorous measures of adsorption, such as the net- and excess adsorbed amounts and a recently developed methodology is
Jarvie Daniel M
Full Text Available Abstract Thermal cracking of kerogens and bitumens is widely accepted as the major source of natural gas (thermal gas. Decomposition is believed to occur at high temperatures, between 100 and 200°C in the subsurface and generally above 300°C in the laboratory. Although there are examples of gas deposits possibly generated at lower temperatures, and reports of gas generation over long periods of time at 100°C, robust gas generation below 100°C under ordinary laboratory conditions is unprecedented. Here we report gas generation under anoxic helium flow at temperatures 300° below thermal cracking temperatures. Gas is generated discontinuously, in distinct aperiodic episodes of near equal intensity. In one three-hour episode at 50°C, six percent of the hydrocarbons (kerogen & bitumen in a Mississippian marine shale decomposed to gas (C1–C5. The same shale generated 72% less gas with helium flow containing 10 ppm O2 and the two gases were compositionally distinct. In sequential isothermal heating cycles (~1 hour, nearly five times more gas was generated at 50°C (57.4 μg C1–C5/g rock than at 350°C by thermal cracking (12 μg C1–C5/g rock. The position that natural gas forms only at high temperatures over geologic time is based largely on pyrolysis experiments under oxic conditions and temperatures where low-temperature gas generation could be suppressed. Our results indicate two paths to gas, a high-temperature thermal path, and a low-temperature catalytic path proceeding 300° below the thermal path. It redefines the time-temperature dimensions of gas habitats and opens the possibility of gas generation at subsurface temperatures previously thought impossible.
Thompson, Jesse B.
A highly profitable petrochemical industry has reemerged in Texas from the boom in U.S. shale oil-and-gas exploration, creating an internationally competitive sector that can produce a variety of products including plastics at a lower cost.
this study re[resents design and manufacturing of a lab-scale circulating fluidized bed (C.F.B) to burn low grade fuel such as Jordanian oil shale. Hydrodynamic properties of C.F.B. were studied like minimum fluidization velocity, circulation flux and carryover rate. a hot run was firstly conducted by the combustion of L.P.G. to start up the combustion process. It proceeds until reaching the minimum burning temperature of oil shale particles, at which time the LPG supply was gradually reduced and oil shale feeding started. soon after reaching a self sustainable condition of oil shale particles, the LPG supply was cut off. The main combustion variables were investigated such as air to fuel ratios, temperature profiles across the bed, exhaust gas analysis and combustion efficiency. a combustion intensity of 859 kg/hr.m2 and combustion efficiency of 96% were achieved. (authors). 19 refs., 9 tab., 18 fig
Washburn, Kathryn E.; Birdwell, Justin E.
Unconventional shale resources may contain a significant amount of hydrogen in organic solids such as kerogen, but it is not possible to directly detect these solids with many NMR systems. Binomial-edited pulse sequences capitalize on magnetization transfer between solids, semi-solids, and liquids to provide an indirect method of detecting solid organic materials in shales. When the organic solids can be directly measured, binomial-editing helps distinguish between different phases. We applied a binomial-edited CPMG pulse sequence to a range of natural and experimentally-altered shale samples. The most substantial signal loss is seen in shales rich in organic solids while fluids associated with inorganic pores seem essentially unaffected. This suggests that binomial-editing is a potential method for determining fluid locations, solid organic content, and kerogen–bitumen discrimination.
Shale gas development in China can generate great potential economic benefits, but also poses serious environmental risks. In this paper, we offer a macro assessment of the environmental risks of shale gas development in China. We use the US experience to identify the nature of shale gas development activities and the types of potential burdens these activities may create. We then review the baseline environmental conditions and the effectiveness of environmental regulations in China and discuss the implications of these China-specific factors for risk assessment. We recommend China to conduct a strategic environmental assessment and to consider sector-specific environmental regulations. - Highlights: • We assess the environmental risks of shale gas development in China. • We use the US experience to identify the potential environmental burdens. • The effectiveness of environmental regulations in China is generally weak. • China lacks environmental regulations specific to the oil and gas sector. • We recommend China to adopt policies to reduce environmental risks
Jordan's long experience in dealing with oil shale as a source of energy is introduced and discussed. Since the 1960s, Jordan has been investigating economical and environmental methods for utilizing this indigenous natural resource, which, due to its high organic content, is considered a suitable source of energy either by direct burning to generate electricity or by retorting to produce oil and gas. More than three decades of comprehensive engineering and economical studies, and test experiments for both retorting and direct burning carried out in co-operation with several international oil shale companies provide a solid foundation for a future oil shale industry in the country. Oil shale utilization in Jordan should be pursued because it will result in significant savings in foreign exchange, improve Jordan's energy supply security and create new jobs. (author)
Jiang, Shu; Xu, Zhengyu; Feng, Youliang; Zhang, Jinchuan; Cai, Dongsheng; Chen, Lei; Wu, Yue; Zhou, Dongsheng; Bao, Shujing; Long, Shengxiang
Organic-rich shales spanning in age from Pre-Cambrian to Quaternary were widely deposited in China. This paper elaborates the geology and unique characteristics of emerging and potential hydrocarbon-bearing shales in China. The Pre-Cambrian Sinian Doushantuo to Silurian black marine shales in the intra-shelf low to slope environments were accumulated in South China and Tarim Platform in Northwest China. These marine shales with maturity (Ro) of 1.3-5% are in dry gas window. During Carboniferous to Permian, the shales associated with coal and sandstones were mainly deposited in coastal swamp transitional setting in north China, NE China, NW China and Yangtze platform in South China. These transitional shales are generally clay rich and are potential gas-bearing reservoirs. Since Middle Permian, the lacustrine shales with total carbon content (TOC) up to 30% and Ro mainly in oil window are widely distributed in all the producing basins in China. The lacustrine shales usually have more clay mineral content than marine shales and are characterized by rapid facies change and are interbedded with carbonates and sandstone. The high quality shale reservoir with high TOC, hydrocarbon content and brittle minerals content is usually located at transgressive systems tract (TST) to early highstand systems tract (EHST) interval deposited in anoxic depositional setting. Recent commercial shale gas production from the Silurian Longmaxi marine shale in the southeastern Sichuan Basin, preliminary tight oil production associated with lacustrine hydrocarbon-bearing shale intervals and hydrocarbon shows from many other shales have proven the hydrocarbon-bearing shales in China are emerging and potential shale gas and tight (shale) oil plays. Tectonic movements could have breached the early hydrocarbon accumulation in shales and tectonically stable areas are suggested to be favorable prospects for China shale plays exploration and production.
Estonia n oil shale was first used as a power fuel in 1924 at the Tallinn Power Plant. The first pulverized oil-shale-fired steam boilers were used in the end of forties. A new period in the utilization of the Estonia n oil shale began in the years of 1959-1960, when the first power units were applied at the Baltic Thermal Power Plant. The project capacity of the plant was 1600 MW. In the 1973 the Estonia n thermal Power Plant was put into operation with the capacity of 1610 MW. The output of the electric power generated by oil.shale power plants in 1989, was 17.4 TWh; the maximum output was achieved in 1979 - 19.1 TWh. In 1989, the amount of the Estonia n oil shale consumed to generate electric power was equal to 22.3·106t. On burning oil shale the main atmospheric pollutants are the following: nitrogen oxides, sulphur oxides, and fly ash. The concentration of nitrogen oxide in the oil-shale flue gas leaving the chimney, expressed as nitrogen dioxide by an excess air factor 1.5, is in the range of 0.15-0.20 g/m3. The total emission of nitrogen oxide into the atmosphere is approximately 15-20 thousand ton per year. the concentration of sulphur dioxide in the oil-shale flue gas leaving the boiler by an excess air factor 1.5 in the range of 1.0-1.8 g/m3. the total emission of sulphur dioxide into atmosphere is in range of 140-160 thousand per year. As the oil-shale ash contains a large amount of the components capable of combining with sulphur in furnace and in boiler gas passes, the sulphur binding effect from ash is high, and it is in the range of 0.75-0.85. The boilers in oil-shale power plants are equipped with two-stage ash separation systems: cyclone and electrostatic al precipitators. The fly ash concentration in oil shale flue gas after electrostatic al precipitators by excess air factor 1.5 is 1-2 g/m3. (author)
Shale gas remains a contentious issue in France. Just as a debate is being initiated in Parliament in preparation for a law on energy programming, it seems crucial to overcome the status quo induced by the law of July 13, 2011 which forbids the mere exploration of this source of energy. According to the Institut Montaigne (a think tank), shale gas represents a core asset for France. (authors)
This bibliographical sheet presents a book which addresses the struggle about energy in which politicians, billionaires and consumers are involved. The authors aim at assessing what is at stake as far as shale gases are concerned, and at discussing who actually decides the French energy policy, what is behind the American shale gas boom as this Eldorado is in financial collapse, and what are the risks associated which this soil exploitation
Recent advances in drilling technology have led to profitable extraction of natural gas from shale gas formations. Shale gas has changed the economics of natural gas production in US as the sudden increase in supply has resulted in significantly lower gas prices. Starting 2008, the difference between gas prices in the United States and Europe has widened, with European gas prices even three times higher as compared to US ones. In North America, coal has been replaced by gas in the US electric...
In the 1990s the extraction of unconventional shale gas extraction increases in the USA due to national and global demand of energy. The expansion of shale gas production will provide low carbon economy, therefore it is a positive side of low greenhouse gas emissions in the atmosphere and considering the benefit sides it has been referred to as a bridging fuel. Horizontal drilling and hydraulic fracturing are the two technologies by the combination with one another; provide the potential to ...
Peter A. O’Connor
Full Text Available The two methods of processing synthetic crude from organic marlstone in demonstration or small-scale commercial status in the U.S. are in situ extraction and surface retorting. The considerable uncertainty surrounding the technological characterization, resource characterization, and choice of the system boundary for oil shale operations indicate that oil shale is only a minor net energy producer if one includes internal energy (energy in the shale that is used during the process as an energy cost. The energy return on investment (EROI for either of these methods is roughly 1.5:1 for the final fuel product. The inclusions or omission of internal energy is a critical question. If only external energy (energy diverted from the economy to produce the fuel is considered, EROI appears to be much higher. In comparison, fuels produced from conventional petroleum show overall EROI of approximately 4.5:1. “At the wellhead” EROI is approximately 2:1 for shale oil (again, considering internal energy and 20:1 for petroleum. The low EROI for oil shale leads to a significant release of greenhouse gases. The large quantities of energy needed to process oil shale, combined with the thermochemistry of the retorting process, produce carbon dioxide and other greenhouse gas emissions. Oil shale unambiguously emits more greenhouse gases than conventional liquid fuels from crude oil feedstocks by a factor of 1.2 to 1.75. Much of the discussion regarding the EROI for oil shale should be regarded as preliminary or speculative due to the very small number of operating facilities that can be assessed.
In exploration for shale gas, reliable estimations of Gas-In-Place (GIP) and portion of technically recoverable resource pose a challenging task. Improvement of our understanding of gas stogare capacity of carbonaceous shales and its evolution during geological history requires carefully designed experiments to obtain reliable experimental data. Moreover, the experimental conditions have to cover a range representative of the in-situ reservoir conditions. This thesis, which was conducted duri...
China will intensify its efforts to explore for shale gas to help restructure the country＇s energy supplies and fuel its economic growth, according to the Ministry of Land and Resources. The ministry＇s latest survey shows that the country has 25.08 trillion cubic meters of explorable shale gas reserves （excluding Qinghai and Tibet）. More than 420 researchers from oil companies, colleges and geological exploration agencies and research institutions participated in the survey.
Jóźwik, Andrzej Krzysztof
The primary purpose of this study was to examine what kind of threats are associated with functioning of the shale gas well testing installation, and also how failures of the installation influence the safety of the residents living nearby. With the development of the shale gas industry in Poland, the discussion about the influence of hydraulic fracturing on the social and environmental safety has been raised. This discussion neglected the risks associated with the surface operations, which t...
Nordsveen, Espen T
Horizontal wells with multistage hydraulic fracturing are today the most important drilling technology for shale gas extraction. Considered unprofitable before, the production has now become economically profitable due to advances in technology. Shales main characteristics is its low permeability, making the gas challenging and expensive to extract. Hydraulic fracturing stimulates the wells by creating additional conductivity, making the gas flows from storage pores to the well. This flow on...
Klaiber, H. Allen; Gopalakrishnan, Sathya
Horizontal drilling and hydraulic fracturing processes to extract shale gas have raised concerns among local residents over the safety of these new drilling techniques. To assess whether potential negative externalities associated with shale gas exploration are capitalized into surrounding homeowners property values, we estimate a hedonic model combining data on 3,464 housing sales occurring between 2008 and 2010 in a suburban/rural county south of Pittsburgh, PA which experienced large numbe...
John Broderick,Kevin Anderson, Ruth Wood, Paul Gilbert, Maria Sharmina, Anthony Footitt, Steven Glynn, Fiona Nicholls
Since 2007, the production of shale gas in large volumes has substantially reduced the wholesale price of natural gas in the US. This report examines the emissions savings in the US power sector, influenced by shale gas, and the concurrent trends in coal exports that may increase emissions in Europe and Asia. Electricity generated by the combustion of natural gas is generally considered to have a lower emissions intensity per unit electricity than that generated by burning coal. The relative ...
The overall objective of the program is to evaluate the environmental and health consequences of the release of toxic trace elements (As, B, F, Mo, Se) by shale oil production and use. Some of the particularly significant results are: The baseline geochemical survey shows that stable trace elements maps can be constructed for numerous elements and that the trends observed are related to geologic and climatic factors. Shale retorted by above-ground processes tends to be very homogeneous (both in space and in time) in trace element content. This implies that the number of analytical determinations required of processed shales is not large. Leachate studies show that significant amounts of B, F, And Mo are released from retorted shales and while B and Mo are rapidly flushed out, F is not. On the other hand, As, Se, and most other trace elements ae not present in significant quantities. Significant amounts of F and B are also found in leachates of raw shales. Very large concentrations of reduced sulfur species are found in leachates of processed shale. Upon oxidation a drastic lowering in pH is observed. Preliminary data indicates that this oxidation is catalyzed by bacteria. Very high levels of B and Mo are taken up in some plants growing on processed shale with and without soil cover. These amounts depend upon the process and various site specific characteristics. In general, the amounts taken up decrease with increasing soil cover. On the other hand, we have not observed significant uptake of As, Se, and F into plants. There is a tendency for some trace elements to associate with specific organic fractions, indicating that organic chelation or complexation may play an important role. In particular, most of the Cd, Se, and Cr in shale oil is associated with the organic fraction containing most of the nitrogen-containing compounds.
Semnani, S. J.; White, J. A.; Borja, R. I.
The present study provides a thermo-mechanical framework for modeling the temperature dependent behavior of oil shale. As a result of heating, oil shale undergoes phase transformations, during which organic matter is converted to petroleum products, e.g. light oil, heavy oil, bitumen, and coke. The change in the constituents and microstructure of shale at high temperatures dramatically alters its mechanical behavior e.g. plastic deformations and strength, as demonstrated by triaxial tests conducted at multiple temperatures [1,2]. Accordingly, the present model formulates the effects of changes in the chemical constituents due to thermal loading. It is well known that due to the layered structure of shale its mechanical properties in the direction parallel to the bedding planes is significantly different from its properties in the perpendicular direction. Although isotropic models simplify the modeling process, they fail to accurately describe the mechanical behavior of these rocks. Therefore, many researchers have studied the anisotropic behavior of rocks, including shale . The current study presents a framework to incorporate the effects of transverse isotropy within a thermo-mechanical formulation. The proposed constitutive model can be readily applied to existing finite element codes to predict the behavior of oil shale in applications such as in-situ retorting process and stability assessment in petroleum reservoirs.  Masri, M. et al."Experimental Study of the Thermomechanical Behavior of the Petroleum Reservoir." SPE Eastern Regional/AAPG Eastern Section Joint Meeting. Society of Petroleum Engineers, 2008.  Xu, B. et al. "Thermal impact on shale deformation/failure behaviors---laboratory studies." 45th US Rock Mechanics/Geomechanics Symposium. American Rock Mechanics Association, 2011.  Crook, AJL et al. "Development of an orthotropic 3D elastoplastic material model for shale." SPE/ISRM Rock Mechanics Conference. Society of Petroleum Engineers
Harak, A.E.; Little, W.E.; Faulders, C.R.
A new concept for above-ground retorting of oil shale was disclosed by A.E. Harak in US Patent No. 4,340,463, dated July 20, 1982, and assigned to the US Department of Energy. This patent titled System for Utilizing Oil Shale Fines, describes a process wherein oil shale fines of one-half inch diameter and less are pyrolyzed in an entrained-flow reactor using hot gas from a cyclone combustor. Spent shale and supplemental fuel are burned at slagging conditions in this combustor. Because of fines utilization, the designation Use It All Retorting Process (UIARP) has been adopted. A preliminary process engineering design of the UIARP, analytical tests on six samples of raw oil shale, and a preliminary technical and economic evaluation of the process were performed. The results of these investigations are summarized in this report. The patent description is included. It was concluded that such changes as deleting air preheating in the slag quench and replacing the condenser with a quench-oil scrubber are recognized as being essential. The addition of an entrained flow raw shale preheater ahead of the cyclone retort is probably required, but final acceptance is felt to be contingent on some verification that adequate reaction time cannot be obtained with only the cyclone, or possibly some other twin-cyclone configuration. Sufficient raw shale preheating could probably be done more simply in another manner, perhaps in a screw conveyor shale transporting system. Results of the technical and economic evaluations of Jacobs Engineering indicate that further investigation of the UIARP is definitely worthwhile. The projected capital and operating costs are competitive with costs of other processes as long as electric power generation and sales are part of the processing facility.
In the time frame beyond 2005, fusion reactors are likely to make their first appearance when the oil shale industry will probably be operating with 20% of the production derived from surface retorts operating on deep mined shale from in situ retorts and 80% from shale retorted within these in situ retorts using relatively fine shale uniformly rubblized by expensive mining methods. A process was developed where fusion reactors supply a 6000C mixture of nitrogen, carbon dioxide, and water vapor to both surface and in situ retorts. The in situ production is accomplished by inert gas retorting, without oxygen, avoiding the burning of oil released from the larger shale particles produced in a simpler mining method. These fusion reactor-heated gases retort the oil from four 50x50x200m in-situ rubble beds at high rate of 40m/d and high yield (i.e., 95% F.A.), which provided high return on investment around 20% for the syncrude selling at $20/bbl, or 30% if sold as $30/bbl for heating oil. The bed of 6000C retorted shale, or char, left behind was then burned by the admission of ambient air in order to recover all of the possible energy from the shale resource. The hot combustion gases, mostly nitrogen, carbon dioxide and water vapor are then heat-exchanged with fusion reactor blanket coolant flow to be sequentially introduced into the next rubble bed ready for retorting. The advantages of this fusion-driven retorting process concept are a cheaper mining method, high yield and higher production rate system, processing with shale grades down to 50 l/mg (12 gpt), improved resource recovery by complete char utilization and low energy losses by leaving behind a cold, spent bed
W. Kanitpanyacharoen; Vasin, R; Wenk, HR; Dewhurst, DN
© 2014 Society of Exploration Geophysicists. The significance of shales for unconventional hydrocarbon reservoirs, nuclear waste repositories, and geologic carbon stor- age has opened new research frontiers in geophysics. Among many of its unique physical properties, elastic anisotropy had long been investigated by experimental and computational ap- proaches. Here, we calculated elastic properties of Cretaceous Muderong Shale from Australia with a self-consistent averaging method based on mic...
Birdsell, Daniel T.; Rajaram, Harihar; Lackey, Greg
Recent studies suggest that imbibition of hydraulic fracturing fluids into partially saturated shale is an important mechanism that restricts their migration, thus reducing the risk of groundwater contamination. We present computations of imbibition based on an exact semianalytical solution for spontaneous imbibition. These computations lead to quantitative estimates of an imbibition rate parameter (A) with units of LT-1/2 for shale, which is related to porous medium and fluid properties, and the initial water saturation. Our calculations suggest that significant fractions of injected fluid volumes (15-95%) can be imbibed in shale gas systems, whereas imbibition volumes in shale oil systems is much lower (3-27%). We present a nondimensionalization of A, which provides insights into the critical factors controlling imbibition, and facilitates the estimation of A based on readily measured porous medium and fluid properties. For a given set of medium and fluid properties, A varies by less than factors of ˜1.8 (gas nonwetting phase) and ˜3.4 (oil nonwetting phase) over the range of initial water saturations reported for the Marcellus shale (0.05-0.6). However, for higher initial water saturations, A decreases significantly. The intrinsic permeability of the shale and the viscosity of the fluids are the most important properties controlling the imbibition rate.
Staten, Josh; Tiwari, Pankaj
This report summarizes a study of oil shale pyrolysis at various scales and the subsequent development a model for in situ production of oil from oil shale. Oil shale from the Mahogany zone of the Green River formation was used in all experiments. Pyrolysis experiments were conducted at four scales, powdered samples (100 mesh) and core samples of 0.75”, 1” and 2.5” diameters. The batch, semibatch and continuous flow pyrolysis experiments were designed to study the effect of temperature (300°C to 500°C), heating rate (1°C/min to 10°C/min), pressure (ambient and 500 psig) and size of the sample on product formation. Comprehensive analyses were performed on reactants and products - liquid, gas and spent shale. These experimental studies were designed to understand the relevant coupled phenomena (reaction kinetics, heat transfer, mass transfer, thermodynamics) at multiple scales. A model for oil shale pyrolysis was developed in the COMSOL multiphysics platform. A general kinetic model was integrated with important physical and chemical phenomena that occur during pyrolysis. The secondary reactions of coking and cracking in the product phase were addressed. The multiscale experimental data generated and the models developed provide an understanding of the simultaneous effects of chemical kinetics, and heat and mass transfer on oil quality and yield. The comprehensive data collected in this study will help advance the move to large-scale in situ oil production from the pyrolysis of oil shale.
Oil shale is the major indigenous fossil-fuel in Jordan: its predicted reserves, of about 5·1010 tonnes, should be sufficient to satisfy Jordan's energy requirements for several centuries. Jordanian oil shale has, on an average, a gross calorific value of between 5 and 7 MJ/kg, an oil yield of ∼ 10 %, and a sulfur content of approximately 3 % by weight of the raw shale (i.e. 7 to 9 % of the organic matter content). Using the oil shale as the input fuel, a multipurpose production process (i.e. retorting, electricity generation, thermal water-desalination, chemicals production as well as mineral extraction) could achieve high utilisation-factors of both its chemical and energy potentials. In the long-term, oil shale is the only indigenous energy resource that could reduce Jordan's dependence on imported crude oil and hence ease the pressure on the national economy. The conversion of oil shale into a liquid or gaseous fuel and raw materials will be of decisive importance in attempts to secure the future of energy supplies. So national efforts devoted to the exploration for, and harnessing more economically, this energy resource, while limiting the associated adverse environmental impacts, should be accelerated. (author)
Yu, Mengjun; Weinthal, Erika; Patiño-Echeverri, Dalia; Deshusses, Marc A; Zou, Caineng; Ni, Yunyan; Vengosh, Avner
Unconventional shale gas development holds promise for reducing the predominant consumption of coal and increasing the utilization of natural gas in China. While China possesses some of the most abundant technically recoverable shale gas resources in the world, water availability could still be a limiting factor for hydraulic fracturing operations, in addition to geological, infrastructural, and technological barriers. Here, we project the baseline water availability for the next 15 years in Sichuan Basin, one of the most promising shale gas basins in China. Our projection shows that continued water demand for the domestic sector in Sichuan Basin could result in high to extremely high water stress in certain areas. By simulating shale gas development and using information from current water use for hydraulic fracturing in Sichuan Basin (20,000-30,000 m(3) per well), we project that during the next decade water use for shale gas development could reach 20-30 million m(3)/year, when shale gas well development is projected to be most active. While this volume is negligible relative to the projected overall domestic water use of ∼36 billion m(3)/year, we posit that intensification of hydraulic fracturing and water use might compete with other water utilization in local water-stress areas in Sichuan Basin. PMID:26881457
This report proposes a multidisciplinary contribution to the debate on shale gas. It first shows that shale gas is already a reality at the international level, that the American economy has improved its competitiveness with direct consequences for the European economy, and notices that some countries which have been reluctant until now, are now evolving. The second part describes the potential of shale gas in France as important but with still uncertain resources. The authors outline that a status-quo would be a threat for the French industry on the short term. Then, the report proposes answers to some questions raised by the exploitation of shale gas in France in terms of risks related to hydraulic fracturing, to water resources, to methane emissions, to organic volatile compounds present in drilling waters, or in terms of noise and visual pollutions. In its last part, the report discusses how to progress in the assessment of the role of shale gas in the French and European energy mix, in the knowledge of the French underground, in the development of shale gas at the service of competitiveness, and with an ensured progressive and controlled evolution
Forster, D.; Perks, J. [AEA Technology plc, London (United Kingdom)
Existing estimates of GHG emissions from shale gas production and available abatement options were used to obtain improved estimates of emissions from possible shale gas exploitation in the EU. GHG emissions per unit of electricity generated from shale gas were estimated to be around 4 to 8% higher than for electricity generated by conventional pipeline gas from within Europe. These additional emissions arise in the pre-combustion stage, predominantly in the well completion phase when the fracturing fluid is brought back to the surface together with released methane. If emissions from well completion are mitigated, through flaring or capture, and utilised, then this difference is reduced to 1 to 5%. The analysis suggests that the emissions from shale gas-based power generation (base case) are 2 to 10% lower than those from electricity generated from sources of conventional pipeline gas located outside of Europe (in Russia and Algeria), and 7 to 10% lower than those from electricity generated from LNG imported into Europe. However, under our 'worst case' shale gas scenario, where all flow back gases at well completion are vented, emissions from electricity generated from shale gas would be similar to the upper emissions level for electricity generated from imported LNG and for gas imported from Russia.
Clark, C.E.; Han, J.; Burnham, A.; Dunn, J.B.; Wang, M. (Energy Systems); ( EVS)
The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. Using the current state of knowledge of the recovery, processing, and distribution of shale gas and conventional natural gas, we have estimated up-to-date, life-cycle greenhouse gas emissions. In addition, we have developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps - such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings - that need to be addressed further. Our base case results show that shale gas life-cycle emissions are 6% lower than those of conventional natural gas. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty regarding whether shale gas emissions are indeed lower than conventional gas emissions. This life-cycle analysis provides insight into the critical stages in the natural gas industry where emissions occur and where opportunities exist to reduce the greenhouse gas footprint of natural gas.
Borysenko, Artem; Clennell, Ben; Sedev, Rossen; Burgar, Iko; Ralston, John; Raven, Mark; Dewhurst, David; Liu, Keyu
Wettability in argillaceous materials is poorly understood, yet it is critical to hydrocarbon recovery in clay-rich reservoirs and capillary seal capacity in both caprocks and fault gouges. The hydrophobic or hydrophilic nature of clay-bearing soils and sediments also controls to a large degree the movement of spilled nonaqueous phase liquids in the subsurface and the options available for remediation of these pollutants. In this paper the wettability of hydrocarbons contacting shales in their natural state and the tendencies for wettability alteration were examined. Water-wet, oil-wet, and mixed-wet shales from wells in Australia were investigated and were compared with simplified model shales (single and mixed minerals) artificially treated in crude oil. The intact natural shale samples (preserved with their original water content) were characterized petrophysically by dielectric spectroscopy and nuclear magnetic resonance, plus scanning electron, optical and fluorescence microscopy. Wettability alteration was studied using spontaneous imbibition, pigment extraction, and the sessile drop method for contact angle measurement. The mineralogy and chemical compositions of the shales were determined by standard methods. By studying pure minerals and natural shales in parallel, a correlation between the petrophysical properties, and wetting behavior was observed. These correlations may potentially be used to assess wettability in downhole measurements.
Roslyakov, P. V.; Attikas, Raivo; Zaichenko, M. N.; Pleshanov, K. A.; Ionkin, I. L.
Results from investigations of joint and separate combustion of shale with a low heating value and oil shale retort gas (OSRG) are presented. The question about the possibility of further using shale as basic fuel is presently placed on the agenda. This matter is connected with the fact that the environmental regulations are imposing increasingly more stringent limits on emissions of harmful substances and that a decrease in the shale heating value is predicted. An adequate mathematical model of one of the TP-101 boilers installed at the Estonian power plant was developed and verified for carrying out investigations. Criteria for determining the reliability, efficiency, and environmental safety of equipment operation were formulated based on the operating chart, regulatory documents, and environmental requirements. Assessment of the possibility of boiler operation and the boiler unit as a whole in firing shale with a low calorific value has shown that despite fulfilling the required superheated steam parameters, quite a number of limitations relating to reliable operation of the boiler are not complied with. In addition, normal operation of forced-draft equipment and mills is possible only at low loads. For operation with joint combustion of shale and OSRG, the fractions of degraded-quality shale and OSRG (by heat) at which reliable and efficient operation of the boiler and boiler unit is ensured in the entire working range of loads with fulfilling the environmental standards are determined. Proposals on modifying the equipment for joint combustion of shale and OSRG are formulated. Boiler operation with firing OSRG as main fuel was modeled for three versions of furnace waterwall thermal efficiency with a view to estimate possible changes of boiler operation in carrying out waterwall cleaning operations. Calculation results have shown that operation of the boiler and boiler unit meeting the elaborated criteria is possible in the entire working range of loads with
Zhang, Yong; Jia, Dong; Yin, Hongwei; Liu, Mancang; Xie, Wuren; Wei, Guoqi; Li, Yongxiang
The organic-rich lower Silurian shale of the Longmaxi Formation in the Sichuan Basin is the most important target for shale-gas exploration in China. Most Paleozoic rocks of the Sichuan Basin have experienced extraordinarily pervasive remagnetizations. To test a hypothesized connection between hydrocarbon generation and remagnetization and contribute to shale-gas exploration in the region, we undertook an integrated magnetic, geochemical, and petrographic study of 160 specimens from the shale. The results suggest that the shale contains a reliable remanent magnetization (Dec = 41.4°, Inc = 40.8°, and α95 = 6.8°). The magnetization predates tilting, and the paleopole plots close to the Late Triassic segment of the south China apparent polar wander path. The rock magnetic data and scanning electron microscope (SEM) observations confirm that framboidal magnetites carry the bulk of the magnetization, which suggest a Late Triassic chemical remanent magnetization in the shale. 87Sr/86Sr and magnetic analyses indicate that the amount of magnetite was unaffected by fluid alterations around the veins but is strongly covariant with the amount of total organic matter. Moreover, SEM observations reveal possible evidence of the replacement of pyrite framboids by magnetite, probably in the presence of organic acids. These analyses, therefore, suggest that the remagnetization was caused by organic maturation rather than orogenic fluids and that the maturation occurred in the Late Triassic. This timing of organic maturation has been validated by independent modeling studies and provides important constraints on the complex thermal history of the Longmaxi Shale as well as contributing to shale-gas exploration efforts.
We construct a rock physics workflow to link the elastic properties of shales to complex constituents and specific microstructure attributes. The key feature in our rock physics model is the degrees of preferred orientation of clay and kerogen particles defined by the proportions of such particles in their total content. The self-consistent approximation method and Backus averaging method are used to consider the isotropic distribution and preferred orientation of compositions and pores in shales. Using the core and well log data from the Barnett Shale, we demonstrate the application of the constructed templates for the evaluation of porosity, lithology and brittleness index. Then, we investigate the brittleness index defined in terms of mineralogy and geomechanical properties. The results show that as clay content increases, Poisson's ratio tends to increase and Young's modulus tends to decrease. Moreover, we find that Poisson's ratio is more sensitive to the variation in the texture of shales resulting from the preferred orientation of clay particles. Finally, based on the constructed rock physics model, we calculate AVO responses from the top and bottom of the Barnett Shale, and the results indicate predictable trends for the variations in porosity, lithology and brittleness index in shales. (paper)
Yang, J.; Torres, M. E.; Kim, J. H.; Verba, C.
The lanthanide series of elements (the 14 rare earth elements, REEs) have similar chemical properties and respond to different chemical and physical processes in the natural environment by developing unique patterns in their concentration distribution when normalized to an average shale REE content. The interpretation of the REE content in a gas-bearing black shale deposited in a marine environment must therefore take into account the paleoredox conditions of deposition as well as any diagenetic remobilization and authigenic mineral formation. We analyzed 15 samples from a core of the Marcellus Shale (Whipkey ST1, Greene Co., PA) for REEs, TOC, gas-producing potential, trace metal content, and carbon isotopes of organic matter in order to determine the REE systematics of a black shale currently undergoing shale gas development. We also conducted a series of sequential leaching experiments targeting the phosphatic fractions in order to evaluate the dominant host phase of REEs in a black shale. Knowledge of the REE system in the Marcellus black shale will allow us to evaluate potential REE release and behavior during hydraulic fracturing operations. Total REE content of the Whipkey ST1 core ranged from 65-185 μg/g and we observed three distinct REE shale-normalized patterns: middle-REE enrichment (MREE/MREE* ~2) with heavy-REE enrichment (HREE/LREE ~1.8-2), flat patterns, and a linear enrichment towards the heavy-REE (HREE/LREE ~1.5-2.5). The MREE enrichment occurred in the high carbonate samples of the Stafford Member overlying the Marcellus Formation. The HREE enrichment occurred in the Union Springs Member of the Marcellus Formation, corresponding to a high TOC peak (TOC ~4.6-6.2 wt%) and moderate carbonate levels (CaCO3 ~4-53 wt%). Results from the sequential leaching experiments suggest that the dominant host of the REEs is the organic fraction of the black shale and that the detrital and authigenic fractions have characteristic MREE enrichments. We present our
Highlights: • First full life cycle assessment of shale gas used for electricity generation. • Comparison with coal, conventional and liquefied gas, nuclear, wind and solar PV. • Shale gas worse than coal for three impacts and better than renewables for four. • It has higher photochemical smog and terrestrial toxicity than the other options. • Shale gas a sound environmental option only if accompanied by stringent regulation. - Abstract: Exploitation of shale gas in the UK is at a very early stage, but with the latest estimates suggesting potential resources of 3.8 × 1013 cubic metres – enough to supply the UK for next 470 years – it is viewed by many as an exciting economic prospect. However, its environmental impacts are currently unknown. This is the focus of this paper which estimates for the first time the life cycle impacts of UK shale gas, assuming its use for electricity generation. Shale gas is compared to fossil-fuel alternatives (conventional gas and coal) and low-carbon options (nuclear, offshore wind and solar photovoltaics). The results suggest that the impacts range widely, depending on the assumptions. For example, the global warming potential (GWP100) of electricity from shale gas ranges from 412 to 1102 g CO2-eq./kWh with a central estimate of 462 g. The central estimates suggest that shale gas is comparable or superior to conventional gas and low-carbon technologies for depletion of abiotic resources, eutrophication, and freshwater, marine and human toxicities. Conversely, it has a higher potential for creation of photochemical oxidants (smog) and terrestrial toxicity than any other option considered. For acidification, shale gas is a better option than coal power but an order of magnitude worse than the other options. The impact on ozone layer depletion is within the range found for conventional gas, but nuclear and wind power are better options still. The results of this research highlight the need for tight regulation and
Engineering advances in Canada are making unconventional gas plays more attractive, and provincial governments are looking to tap the economic benefits. Regulators are adjusting existing oil and gas regulations or drafting completely new legislation. This paper presented an overview of the rules for shale gas development in provinces with shale gas development potential, with particular reference to the following 4 regions: (1) British Columbia, Alberta, and Saskatchewan where natural gas development is a relatively well-established and significant part of the local economy, (2) Nova Scotia and New Brunswick where shale gas stands to significantly change the regulatory environment, (3) Quebec where local opposition to shale gas development is challenging for a provincial government that has relatively little experience in the area of oil and gas regulation, and (4) Ontario, where development potential seems to be limited. The paper identified 3 areas that often receive the most attention from regulators, notably tenure and development approval, with a focus on lands where gas rights are owned by the provincial crown; royalties, including any shale-specific incentive programs; and environmental regulation, with a focus on sourcing and use of water, management of produced and recovered waste water, and rules regarding frac fluid. The paper provided a big picture of Canada's legal system and then discussed the provincial situations. The future of shale policy and the American experience concluded the report. It was concluded that it is unlikely that the federal government of Canada will play a lead role in regulating shale development in this country. refs., figs.
The feasibility of nondestructive analysis of oil shales using the prompt gamma neutron activation analysis (PGNAA) technique was studied. The PGNAA technique, developed originally for continuous analysis of coal on the belt, was applied to the analysis of eight oil-shale samples, containing between 9 and 60 gallons of oil per ton and 0.8% to 3.4% hydrogen. The PGNAA technique was modified using four neutron moderation conditions: non-moderated neutrons; non-moderated and partially moderated neutrons reflected from a water box behind the source; neutrons moderated in a water box behind and in front of the source; and neutrons strongly moderated in a polyethylene block placed in front of the source and with reflected neutrons from a water box behind the source. The studied oil shales were measured in their aluminum or wooden (masonite) boxes. The obtained Ge-Li spectra were processed by LSI-11/23 computer, using the modified programs previously developed by SAI for continuous coal analysis. The results of such processing (the peak areas for several gamma lines) were corrected and plotted against the weight percent of each analyzed element (from the chemical analysis). Response curves developed for H, C, N, S, Na, Mg, Al, Si, Ti, Ca, Fe and K show generally good linear proportions of peak area to the weight percent of the element. For hydrogen determination, NMD conditions had to be used where the response curve was not linear, but followed a curve whose slope rose with hydrogen concentration. This effect is caused by improving neutron self-moderation in sample boxes of rich oil shales, as compared to poor self-moderation of neutrons in very lean oil shales. The moisture in oil shales was measured by microwave absorption technique in small masonite boxes. This method was calibrated four times using oil-shale samples mixed gradually with larger and larger amounts of water
Maly, J.; Bozorgmanesh, H.
The feasibility of nondestructive analysis of oil shales using the prompt gamma neutron activation analysis (PGNAA) technique was studied. The PGNAA technique, developed originally for continuous analysis of coal on the belt, was applied to the analysis of eight oil-shale samples, containing between 9 and 60 gallons of oil per ton and 0.8% to 3.4% hydrogen. The PGNAA technique was modified using four neutron moderation conditions: non-moderated neutrons; non-moderated and partially moderated neutrons reflected from a water box behind the source; neutrons moderated in a water box behind and in front of the source; and neutrons strongly moderated in a polyethylene block placed in front of the source and with reflected neutrons from a water box behind the source. The studied oil shales were measured in their aluminum or wooden (masonite) boxes. The obtained Ge-Li spectra were processed by LSI-11/23 computer, using the modified programs previously developed by SAI for continuous coal analysis. The results of such processing (the peak areas for several gamma lines) were corrected and plotted against the weight percent of each analyzed element (from the chemical analysis). Response curves developed for H, C, N, S, Na, Mg, Al, Si, Ti, Ca, Fe and K show generally good linear proportions of peak area to the weight percent of the element. For hydrogen determination, NMD conditions had to be used where the response curve was not linear, but followed a curve whose slope rose with hydrogen concentration. This effect is caused by improving neutron self-moderation in sample boxes of rich oil shales, as compared to poor self-moderation of neutrons in very lean oil shales. The moisture in oil shales was measured by microwave absorption technique in small masonite boxes. This method was calibrated four times using oil-shale samples mixed gradually with larger and larger amounts of water.
Roberts, M.J.; Mensinger, M.C.; Rue, D.M.; Lau, F.S. (Institute of Gas Technology, Chicago, IL (United States)); Schultz, C.W. (Alabama Univ., University, AL (United States)); Parekh, B.K. (Kentucky Univ., Lexington, KY (United States)); Misra, M. (Nevada Univ., Reno, NV (United States)); Bonner, W.P. (Tennessee Technological Univ., Cookeville, TN (United States))
The Devonian oil shales of the Eastern United States are a significant domestic energy resource. The overall objective of the multi-year program, initiated in October 1987 by the US Department of Energy is to perform the research necessary to develop the Pressurized Fluidized-Bed Hydroretorting (PFH) process for producing oil from Eastern oil shales. The program also incorporates research on technologies in areas such as raw shale preparation, beneficiation, product separation, and waste disposal that have the potential of improving the economics and/or environmental acceptability of recovering oil from oil shales using the PFH process. The results of the original 3-year program, which was concluded in May 1991, have been summarized in a four-volume final report published by IGT. DOE subsequently approved a 1-year extension to the program to further develop the PFH process specifically for application to beneficiated shale as feedstock. Studies have shown that beneficiated shale is the preferred feedstock for pressurized hydroretorting. The program extension is divided into the following active tasks. Task 3. testing of process improvement concepts; Task 4. beneficiation research; Task 5. operation of PFH on beneficiated shale; Task 6. environmental data and mitigation analyses; Task 7. sample procurement, preparation, and characterization; and Task 8. project management and reporting. In order to accomplish all the program objectives, the Institute of Gas Technology (IGT), the prime contractor, worked with four other institutions: the University of Alabama/Mineral Resources Institute (MRI), the University of Kentucky Center for Applied Energy Research (UK-CAER), the University of Nevada (UN) at Reno, and Tennessee Technological University (TTU). This report presents the work performed during the program extension from June 1, 1991 through May 31, 1992.
Hydraulic fracturing of deep shale beds to develop natural gas has caused concern regarding the potential for various forms of water pollution. Two potential pathways-advective transport through bulk media and preferential flow through fractures-could allow the transport of contaminants from the fractured shale to aquifers. There is substantial geologic evidence that natural vertical flow drives contaminants, mostly brine, to near the surface from deep evaporite sources. Interpretative modeling shows that advective transport could require up to tens of thousands of years to move contaminants to the surface, but also that fracking the shale could reduce that transport time to tens or hundreds of years. Conductive faults or fracture zones, as found throughout the Marcellus shale region, could reduce the travel time further. Injection of up to 15,000,000 L of fluid into the shale generates high pressure at the well, which decreases with distance from the well and with time after injection as the fluid advects through the shale. The advection displaces native fluids, mostly brine, and fractures the bulk media widening existing fractures. Simulated pressure returns to pre-injection levels in about 300 d. The overall system requires from 3 to 6 years to reach a new equilibrium reflecting the significant changes caused by fracking the shale, which could allow advective transport to aquifers in less than 10 years. The rapid expansion of hydraulic fracturing requires that monitoring systems be employed to track the movement of contaminants and that gas wells have a reasonable offset from faults. PMID:22509908
Patcas, F.C.; Dieterle, M.; Rezai, A.; Asprion, N. [BASF SE, Ludwigshafen (Germany)
The discovery and use of shale gas in North America has become a game changer for the chemical industry by access to a cheaper feedstock compared to conventional oil. Increased number of ethane crackers spurred increasing interest in light alkanes dehydrogenation. Several companies have announced their interest in new propane dehydrogenation units in North America. BASF is developing light alkanes dehydrogenation technologies for two decades now. BASF developed jointly with Linde the isothermal C3 dehydrogenation process. The latest dehydrogenation catalyst development at BASF focused on a supported and steam resistant Pt-Sn catalyst which yielded excellent selectivity and activity. Intense research work both internally as well as in cooperation with universities contributed to the understanding of the relationship between the surface structure and catalyst performances like activity, selectivity and coking resistance. Using such type of catalysts BASF developed an autothermal propane dehydrogenation as well as a butane dehydrogenation process. The most recent catalyst development was a dehydrogenation catalyst coated on a honeycomb monolith to improve catalyst usage and pressure drop. This will probably be the first industrial usage of catalytic monoliths in a chemical synthesis process. (orig.) (Published in summary form only)