Hydraulic Mining Research Articles

Slurrified Heavy-Oil-Reservoir Extraction as a Recovery Method

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 165498, ’Slurrified Heavy-Oil-Reservoir Extraction (SHORE): A Nonthermal, In-Situ Recovery Method,’ by David P. Yale and Jianlin Wang, ExxonMobil Upstream Research; Steven W. Meier, Eric Herbolzheimer, and Arnold P. Kushnick, ExxonMobil Research and Engineering; Neal L. Adair and Sergio A. Leonardi, ExxonMobil Upstream Research; and Richard J. Smith, Imperial Oil Resources, prepared for the 2013 SPE Heavy Oil Conference—Canada, Calgary, 11-13 June. The paper has not been peer reviewed. This paper presents a concept for recovery in Canadian oil sands that uses water injection to condition a reservoir interval sufficiently to relieve the overburden stress on the oil sand and increase its porosity and permeability. The ability of the process to work in thinner and more geologically complex reservoirs compared with other in-situ processes, and with lower CO2 and surface footprints than those seen in thermal and mining processes, could make this an attractive alternative recovery process for shallow- to intermediate-depth in-situ bitumen resources. Introduction Canadian oil-sands recovery is challenged by the high and ultrahigh viscosity of the heavy oil and bitumen trapped within the generally unconsolidated sand matrix of these reservoirs. Steam processes have dominated the in situ recovery of this resource, but steam/ solvent and solvent-only processes are currently being field tested. Steam processes, especially low-pressure processes such as steam-assisted gravity drainage (SAGD), are challenged by both a high degree of geologic heterogeneity and thin pay zones. In-Situ Mining of Oil Sands The very shallow (less than 70-m) depth of a large portion of the oil-sand deposits of Canada has made their surface mining a technically feasible and economical method of recovering the bitumen from the shallowest portion of the oil sands. The success of surface mining for bitumen has led others to propose and test in-situ bitumen mining processes. Hydraulic mining of the oil sands from a borehole has a rich patent literature but few conclusive field tests. The basic concept is that a high-pressure, downhole water jet could disrupt the unconsolidated sand matrix around the wellbore such that a bitumen/water/sand slurry could then be produced to the surface for bitumen extraction with surface-mining techniques. The process is technically challenged by the limited volume of hydrocarbons that can be recovered from any given wellbore and the limited “cavern” size that can be supported without roof collapse in these unconsolidated sand/shale geologic environments.

APPLICATION OF FLAC3D FOR SIMULATION OF THE BOREHOLE HYDRAULIC MINING OF NONG’AN OIL SHALE

The analysis software, FLAC3D, was used for simulation of Nong'an oil shale mining according to the three-dimensional fast Lagrangian algorithm. A simulation study involving drilling hydraulic mining methods for different borehole spacings in the Nong'an oil shale mining area was conducted. The best mining scheme was selected in terms of safety factors and economic benefits, and used for the analysis of the vertical displacement and ground surface settlement of the oil shale area. Drill hole spacing was identified as a key factor for the coefficient of borehole hydraulic mining based on the general relationship between the coefficient and borehole spacing. The optimal mining hole spacing was 25 m, and the distribution regularities of the vertical displacement of the surrounding rock near the excavation and earth surface were observed. The results showed that FLAC3D can simulate and analyze the oil shale hydraulic mining process and is an effective and suitable method for oil shale exploitation research.

Research to Break Oil Shale with High Pressure Water Jet Based on Bionic Nozzle

Oil shale is a sedimentary rock, it is increasingly attracting widespread attention as petroleum supplement energy. Using borehole hydraulic mining techniques to mine oil shale seams at a certain depth in the underground, first and foremost is the use of high pressure water jet to make the overall oil shale ore broken into small pieces and peel them off parent rock. Based on the bionic theories, to design the bionic nozzles are adding several bionic units in the internal flow channel surface of the nozzle, it makes the original smooth flow channel inside the nozzle has become bionic non-smooth surface structure, to some extent, effectively improved the hydraulic characteristics of the nozzle internal flow channel, and reduced the flow resistance of the water. Based on CFD simulation and analysis, the reasons for upgrading effect of the crushed oil shale by the bionic nozzle high pressure water jet are analyzed. Experiments show that, in the same working conditions, bionic nozzle compared with the normal nozzle of the same structure parameters, the diameter of the erosion and crushing pit on oil shale samples expanded 4mm, and the crushing pit depth deepened 3.8mm using bionic nozzle.

Research on Nong'an Oil Shale Hydraulic Breaking

Oil shale is a very important alternative energy, hydraulic mining is an effective method for oil shale utilization in Jilin Province. For the Nong'an oil shale in Jilin Province, the average compressive strength of horizontal bedding is 17.14MPa, and the average compressive strength of vertical bedding is 10.90MPa. For cone straight-shaped nozzle, when the jet pressure P is 10MPa and the nozzle outlet diameter d is 1mm, striking force generated by the jet is 15.65N, it can break the oil shale.

The Development of the LWD-200B Full Hydraulic Open Cut Mine Drill

In order to improve the technical level, perforation efficiency and ability of LWD-200B full hydraulic open cut mine drill to adapt to the complex geological conditions, we developed LWD-200B multi-function full hydraulic open cut mine drill, the drill has rotary cutting, impact and roller bit drill three functions.The drill travel use hydraulic motor to drive crawler belt running gear, low speed high torque hydraulic motor to direct top drive drilling rod. Pressure and lifting system use a long stroke hydraulic cylinder, wire rope and pulley mechanism, load sensing constant power variable pump , load sensing electromagnetic proportional multi-way directional valve. The control system uses electronic control handle and PLC controller, design pressure, speed, length, temperature sensors etc. and GPS base station, with real-time data acquisition, display, lithology automatic identification, closed-loop feedback control, GPS precise positioning , the manual and automatic drilling, specified depth or level drilling function. It applies to drilling diameter 150mm ~ 200mm blast hole in various types of open pit mine.

Full Hydraulic and Control Systems Application in Open-Cut Mine Drill

The LWD-200B full hydraulic open cut mine drill's hydraulic system uses a variable displacement pump with load sensing constant power, load sensitive electromagnetic proportional multi-way directional valve, high torque hydraulic motor overhead direct drive rotary head, a long stroke hydraulic cylinder and steel wire rope and pulley speed lifting system, hydraulic cylinder to drive the unloading rod mechanism, hydraulic motor driving crawler, double hydraulic cylinder lifting the drill frame mechanism, a hydraulic motor driven cable winding drum, hydraulic legs leveling method. Control system adopts the control handle and the PLC control mode, with real-time data acquisition, computer automatic recognition of lithology and closed loop feedback control and GPS precise positioning function, to achieving the automatic or manual drilling, specified depth or level drilling. Through the test of practice, it is a multifunctional, fully hydraulic, which is intelligent and efficient perforation equipment.

Adjustment of the San Francisco estuary and watershed to decreasing sediment supply in the 20th century

The general progression of human land use is an initial disturbance (e.g., deforestation, mining, agricultural expansion, overgrazing, and urbanization) that creates a sediment pulse to an estuary followed by dams that reduce sediment supply. We present a conceptual model of the effects of increasing followed by decreasing sediment supply that includes four sequential regimes, which propagate downstream: a stationary natural regime, transient increasing sediment supply, transient decreasing sediment supply, and a stationary altered regime. The model features characteristic lines that separate the four regimes. Previous studies of the San Francisco Estuary and watershed are synthesized in the context of this conceptual model. Hydraulic mining for gold in the watershed increased sediment supply to the estuary in the late 1800s. Adjustment to decreasing sediment supply began in the watershed and upper estuary around 1900 and in the lower estuary in the 1950s. Large freshwater flow in the late 1990s caused a step adjustment throughout the estuary and watershed. It is likely that the estuary and watershed are still capable of adjusting but further adjustment will be as steps that occur only during greater floods than previously experienced during the adjustment period. Humans are actively managing the system to try to prevent greater floods. If this hypothesis of step changes occurring for larger flows is true, then the return interval of step changes will increase or, if humans successfully control floods in perpetuity, there will be no more step changes.

Field Guide to California Agriculture by Paul F. Starrs and Peter Goin (review)

Reviewed by: Field Guide to California Agriculture by Paul F. Starrs and Peter Goin Ron Davidson (bio) Field Guide to California Agriculture Paul F. Starrs and Peter Goin University of California Press, 2010 Paul F. Starrs and Peter Goin have written a lavishly informative, almost 500-page Field Guide to California Agriculture hoping to connect the state’s metropolites with its working agricultural landscapes. Their cause is noble, given the economic, culinary, and ecological importance of local agriculture to Californians and the fact that, indeed, the $37 billion agro-industry (in 2007) occupying a quarter of the state’s surface area absorbs all too little of a typical resident’s attention. Geographer James J. Parsons may find the Central Valley “the most interesting place in the world” (394), but that shows a refined intelligence indeed. For the ninety-four percent of Californians who live in urban areas, the Valley more likely seems the opposite, a plain of almost derangement-inducing monotony broken by pit stops at boisterous, air-conditioned caravanserai. Outside these havens, the Valley may seem rich in strange odors and windshield-spattering micro-life, but little of abiding interest. The Field Guide seeks to turn things around. Travelers equipped with a copy on the dashboard may begin to see the Valley—along with the state’s other agricultural regions and landscapes—as a place worthy of “exploration and discovery” (xx). To encourage this about-face, the authors provide an informative text that is brisk, enthusiastic in tone, and entertaining to read. “Peppers have a justly earned fame for their varying hotness,” they note in typical style, “judged by Scoville heat units, which range from zero (for the bell pepper) to an exotic pepper from Assam, India, that clocked in at a million SHUs” (295). To get things going, the Guide offers a seventy-page crash course on the background and context of California agriculture. Topics include climate, water issues, agricultural technologies, and economics. This introductory [End Page 179] material, along with a later chapter on agricultural regions, makes the Guide something of a stealth geography textbook. (The book is sprinkled with references to and encouragements to read Yi-Fu Tuan, John Fraser Hart, James Parsons, Paul Starrs, and other geographers). As a textbook, perhaps its most notable accomplishment is offering a geographic vision of California’s agricultural regions. This vision has the Bay Area as the state’s core, with Marin County and UC Berkeley at center stage. Citing the Marin Agricultural Land Trust, which preserves dairies and other agricultural landscapes on the county’s west side, the authors note that Marin has had a widespread influence on consumer attitudes relating to “environmental quality, philosophy, and the conservation of agricultural resources” (373). UC Berkeley, near the Oakland terminus of the nation’s first transcontinental railroad and the Golden Gate—and hence at a national and world distribution hub for the state’s agricultural products—historically led the state in innovations in soil science, equipment design, plant breeding, labor management, innovative financing, and other components of the agro-industry. The Bay Area is also ground zero of “foodie” culture and a wine-tasting mecca. By its nature, the Guide is celebratory rather than critical of its subject. It does not challenge the dominant paradigm of large-scale, fossil-fuel-intensive agriculture or the exploitation of agricultural laborers. On the contrary, the Guide was conceived to enhance appreciation of this among other working agricultural models. In addition, readers should be apprised that the text occasionally misreports information and, because of its breakneck pace, sometimes refers to material so fleetingly that it risks misrepresenting it. (The Salton Sea was not created by mistake “in the 1910s” [409], but in 1905–06; the Great Flood of 1862 was not caused solely by “weather,” as the authors imply [29], but also by erosion resulting from hydraulic mining operations in the Sierras. As for questionable representations, the authors cite Julie Guthman, a trenchant critic of how the state’s organic agricultural sector has mimicked its industrial twin, when noting almost triumphantly that “even the organic sector in California is industrializing and attaining a global reach” [13]; Donald Worster’s devastating...

Tidal Marsh Vegetation of China Camp, San Pablo Bay, California

China Camp (Marin County, California) preserves extensive relict stands of salt marsh vegetation developed on a prehistoric salt marsh platform with a complex sinuous tidal creek network. The low salt marsh along tidal creeks supports extensive native stands of Pacific cordgrass (Spartina foliosa). The outer salt marsh accreted following hydraulic gold mining sedimentation. It consists of a wave-scarped pickleweed-dominated (Sarcocornia pacifica) high salt marsh terrace with a broad fringing low marsh dominated by S. foliosa, including intermittent, variable stands of alkali-bulrush (Bolboschoenus maritimus). Most of the extensive prehistoric salt marsh plains within the tidal creek network also support mixed assemblages of S. pacifica, but high marsh zones along tidal creek banks support nearly continuous linear stands of gumplant (Grindelia stricta) and saltgrass (Distichlis spicata) with more diverse salt marsh forb assemblages. Salt pans with submerged wigeongrass (Ruppia maritima) are scarce, local, and small. The landward edge of the tidal marsh forms rare examples of ecotones with adjacent terrestrial vegetation, including those of alluvial valleys (riparian scrub and woodland, freshwater marsh, sedge-rush meadows) and hillslope grassland and oak woodland vegetation. Narrow high tidal marsh ecotones bordering terrestrial grasslands are locally dominated by creeping wildrye (Elymus triticoides) and Baltic rush (Juncus balticus), mostly on south-facing slopes. Brackish tidal marsh ecotones above ordinary high tides are associated with freshwater discharges from groundwater and surface flows. Brackish marsh ecotones support large clonal stands of sedge, bulrush, and rush vegetation (Carex praegracilis, C. barbarae, Bolboschoenus maritimus, Juncus phaeocephalus, Schoenoplectus acutus), intergrading with terrestrial freshwater wetlands and salt marsh. The terrestrial ecotone assemblages at China Camp are comparable with those of other prehistoric tidal marshes in the San Francisco Estuary, but China Camp lacks most native clonal perennial Asteraceae and halophytic annual forbs of the region’s remnant high tidal marsh ecotones. Few globally rare salt marsh plant populations have been reported from China Camp within the National Estuarine Research Reserve and State Park boundaries, but some species regionally uncommon in San Francisco Bay tidal marshes occur. To date, non-native tidal marsh plant invasions have been relatively minor and localized within China Camp.

Research of Experiment Platform for Drilling Hydraulic Mining of Oil Shale

Aimed at a new mining method of oil shale—Borehole Hydraulic Mining, the experiment platform for Borehole Hydraulic mining of oil shale is designed based on this, in order to evaluation of the effective damage to oil shale in different forms of jet, determine the economic and reasonable high-pressure jet parameters. The finite element analysis is conducted to the key components of the experimental platform. The Results Show that the parts design is reasonable and the experiment platform meets the requirements. The experimental platform provides the reliable equipment guarantee for the effective implementation of the hydraulic mining experiment.

The Numerical Simulation for Seepage Rule of Coal-Bed Methane with Hydraulic Cutting Seam Mining Based on Matlab

It’s an effective ways to hydraulic-cutting seam for drainage that solves gas disaster and prevents impact pressure in mining. In order to get the seepage rule and productivity prediction of hydraulic-cutting for coal-bed methane(CBM) mining, the theory of seepage mechanics combined with elastic-plastic mechanics was used to set up a mathematical model and the boundary conditions and initial conditions was given meanwhile. The Matlab software was used to obtain the variation rule of coal-bed stress field, gas pressure field and gas extraction yield. The simulation results show that the effective stress is released after hydraulic-cutting seam used and the effect of unload is obvious along seam; the numbers of crack and fracture increases and the length and width of crack and fracture improve. So the permeability of coal seam enhanced and the absorbed gas disorpted greatly from coal seam because of the increase of contact area. The extraction yield of gas is bigger to hydraulic-cutting seam than conventional drilling. The simulation results show the advantage of hydraulic-cutting seam for CBM extraction and the method of simulation is significant to the execution project and productivity prediction of hydraulic-cutting seam for CBM industrial production increasing technology.

The sound subsoil management in surface coal mining in terms of the Kansk-Achinsk coal basin

Considering characteristics of geological and mining conditions at the Kansk-Achinsk brown coal basin, the authors prove the necessity for non-standard geotechnology application. A new predrainage-free geotechnology application has been described for watered flat coal strata, which ensures complete utilization of mineral reserves and mined-out areas as well as improves environmental safety. It is recommended to selectively extract hard dirt inclusions, if present, by hydraulic mining scheme. The article discusses feasible after-mining utilization of the disturbed lands.

PHYSICAL AND MECHANICAL PARAMETERS OF BOREHOLE HYDRAULIC MINING OF NONG’AN OIL SHALE

The experiments on physics and mechanics of borehole hydraulic mining were designed to determine mechanical characteristics of mined oil shale. Oil shale of Nong'an deposit belongs to slightly weathered and relatively complete rocks. Oil shale beds are characterized by a very definite discontinuity in both horizontal bedding orientation and vertical bedding direction. Compressive strength, tensile strength, Poisson's ratio and other data characterizing oil shale beds in different directions in the Nong'an min- ing site were obtained and compared. The direction of borehole hydraulic mining was determined. The vertical bedding direction to break oil shale was considered to be better, because strength in this direction is low, rock mass integrity poor, and the degree of weathering more pronounced. The diameter of borer nozzle, dynamic pressure, maximum caving capacity and other parameters needed for borehole hydraulic mining were selected.

Process‐based, morphodynamic hindcast of decadal deposition patterns in San Pablo Bay, California, 1856–1887

This study investigates the possibility of hindcasting‐observed decadal‐scale morphologic change in San Pablo Bay, a subembayment of the San Francisco Estuary, California, USA, by means of a 3‐D numerical model (Delft3D). The hindcast period, 1856–1887, is characterized by upstream hydraulic mining that resulted in a high sediment input to the estuary. The model includes wind waves, salt water and fresh water interactions, and graded sediment transport, among others. Simplified initial conditions and hydrodynamic forcing were necessary because detailed historic descriptions were lacking. Model results show significant skill. The river discharge and sediment concentration have a strong positive influence on deposition volumes. Waves decrease deposition rates and have, together with tidal movement, the greatest effect on sediment distribution within San Pablo Bay. The applied process‐based (or reductionist) modeling approach is valuable once reasonable values for model parameters and hydrodynamic forcing are obtained. Sensitivity analysis reveals the dominant forcing of the system and suggests that the model planform plays a dominant role in the morphodynamic development. A detailed physical explanation of the model outcomes is difficult because of the high nonlinearity of the processes. Process formulation refinement, a more detailed description of the forcing, or further model parameter variations may lead to an enhanced model performance, albeit to a limited extent. The approach potentially provides a sound basis for prediction of future developments. Parallel use of highly schematized box models and a process‐based approach as described in the present work is probably the most valuable method to assess decadal morphodynamic development.

Tailings Dam Stability Analysis of the Process of Recovery

China has the world's largest tailings, there's a lot you can reuse of resources, while the presence of tailings has also brought a huge security risk.Tailings recovery can not only reuse of resources,but also eliminate security risks.As Kuguojing Tailings of Jiudingshan for example, numerical analysis using ANSYS software, the process of hydraulic mining tailings three special operating point, the body of the stability of the tailings dam were calculated. Calculated: the process of recovery in the tailings, tailings dam safety factor of three heights are to meet the requirements, the overall stability of the dam is better, will not be very large landslide damage, but a lower safety margin.

The Application Research on Backfill Mining Technology of Gangue for Coal Pillar Mining in Xingtai Mining Village

Gangue and fly ash combined mining technology is the direct filling of the gangue and fly ash to the surface by the feed delivered to the face well, and then filling is in gob areas, while ensuring under the premise of the safe use of surface buildings subjects to the normal maximum level for achieving Coal Mining under the buildings. In the paper, gangue and fly ash on the exploitation of the feed system were designed for filling and compaction equipment, the hydraulic mining was developed on the backfill mining, the conveyor was modified, and the gangue and fly ash mining technology were designed. As the result, the filling rate and surface subsidence was controlled effectively, the service life of the mine was extended, and the good economic and social benefits were achieved.

Mercury-Contaminated Hydraulic Mining Debris in San Francisco Bay

The hydraulic gold-mining process used during the Californhttia Gold Rush and in many developing countries today contributes enormous amounts of sediment to rivers and streams. Commonly, accompanying this sediment are contaminants such as elemental mercury and cyanide used in the gold extraction process. We show that some of the mercury-contaminated sediment created by hydraulic gold mining in the Sierra Nevada, between 1852 and 1884, ended up over 250 kilometers (km) away in San Francisco Bay; an example of the far-reaching extent of contamination from such activities. A combination of radionuclide dating, bathymetric reconstruction, and geochemical tracers were used to distinguish the hydraulic mining sediment from sediment deposited in the bay before hydraulic mining started (pre-Gold Rush sediment) and sediment deposited after hydraulic mining stopped (modern sediment). Three San Francisco Bay cores were studied as well as source material from the abandoned hydraulic gold mines and river sediment between the mines and bay. Isotopic and geochemical compositions of the core sediments show a geochemical shift in sediment deposited during the time of hydraulic mining. The geochemical shift is characterized by a decrease in eNd, total organic carbon (TOC), Sr and Ca concentrations, Ca/Sr, and Ni/Zr; and, an increase in 87 Sr/ 86 Sr, Al/Ca, Hg concentrations, and quartz/ plagioclase. This shift is in the direction of the geochemical signature of sediments from rivers and gold mines in hydraulic mining areas. Mixing calculations using Nd isotopes and concentrations estimate that the hydraulic mining debris comprises up to 56% of the sediment in core sediments deposited during the time of hydraulic mining. The surface sediment of cores taken in 1990 were found to contain up to 43% hydraulic mining debris, reflecting a continuing remobilization and redistribution of the debris within the bay and transport from the watershed. Mercury concentrations in pre-Gold Rush sediment range between 0.03 and 0.08 µg g -1 . In core sediments that have characteristics of the gold deposits and were deposited during the time of hydraulic mining, mercury concentrations can be up to 0.45 µg g -1 . Modern sediment (post-1952 deposition) contains mercury concentrations up to 0.79 µg g -1 and is likely a mix of hydraulic mining mercury and mercury introduced from other sources.

An approach for optimization of loading cycles of hydraulic mining excavators

AbstractThe present paper describes an optimization multi‐stage approach for computing the optimal loading cycle of a heavy weight excavator along a predefined trajectory under dynamic constraints such as maximal ensuing forces, accelerations, and maximal allowed hydraulic power. The approach involves the use of splines of 3rd and 5th order for smooth interpolation of the spatial trajectory up to the level of linear and angular accelerations, as well as an SQP optimization routine to find the optimal end‐effector motion law along the trajectory, which finally leads to strokes and pressures at the hydraulic actuators as a function of time. The approach can also be extended to other multi‐body systems following a predetermined trajectory. The solution scheme can be included in a more general optimization routine aiming to optimize the trajectory itself. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Using Taguchi methods to improve the production process quality: A case study

The Taguchi method represents a remarkable improvement of the classic experiment plan method. The Japanese specialist elaborated some standard instruments which simplify the experimenting process and which can be applied in a wide range of domains, that is to say ‘a collection’ of orthogonally fractioned experiment matrices and a set of ‘accessories’ – triangular tables and linear graphics which enables standard matrices to adapt to specific situations. In Taguchi's terminology, the factors that cause quality losses are called noise factors, while the performance levels targeted are called signals. Taguchi evaluates the quality of a product or of a manufacturing process through a performance synthetic indicator called signal/noise ratio, which takes into consideration both the average value of the targeted performance and its dispersion simultaneously. The paper also contains a case study regarding the quality improvement of the electrochemical cadmium plating in the drum in order to protect the representative parts of the hydraulic mining equipment. The quality criterion is the thickness of the cadmium layer target criterion. Finding the optimum configuration of the process requires the arbitration between representative factor levels in order to reach the double objective: minimising the variance and reaching an average thickness closer to the target value.

Moving Frontiers in the Amazon: Brazilian Small-Scale Gold Miners in Suriname

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