共查询到20条相似文献，搜索用时 31 毫秒
1.
The hydrogeomechanical problems of mining are considered, which deal with rocks and ground water as a single mechanical system.
Among these problems are the openpits slopes stability, rocks consolidation and surface subsidence due to ground water level
lowering, water inrushes into mine workings, rock bursts prevention by using the water injection into the advance boreholes,
etc. The paper contains the basic theoretical grounds, as well as in-situ and laboratory methods for the investigation of
these processes.
The combined study of ground water regime and rock deformations has resulted in the theoretical substantiation of the hydrodynamic
and geomechanical processes within the scope of unique scientific direction-hydrogeomechanics (Mironenko, 1974). The hydrogeomechanical
models are widely used now for the analysis and forecasting the extremely important processes connected with the safe and
efficient mining operations, as well as with the protection of geological medium. Among these processes are:
相似文献
| – | o deformations of the open-pit slopes and spoil dumps; |
| – | o consolidation of rocks due to the ground-water pressure drop; |
| – | o water-and-rock material inrushes into mine workings caused by deformations of the undermined rock mass; |
| – | o geodynamical processes due to the changes in ground water regime; |
| – | o artificial hydrofracturing in rocks; |
| – | o transformations of clay linings under the tailing ponds and other technical water basins |
2.
A. S. Latkin 《Journal of Mining Science》1998,34(3):278-282
Conclusions The prospect of switch-over of the industry to processing lean materials raises the problem of beneficiation of finely disperse
placers of noble metals, the profitability of realization of which lies in raising the efficiency of separation processes
by reducing frictional forces in the course of implementation of the technological processes and by employing modern technologies
for beneficiation. The engineering—technological solutions worked out are distinguished by ecological safety during implementation
of the beneficiation processes.
The proposed schemes of beneficiation and primary processing of finely disperse minerals may be used:
Scientific Research Center, Far Eastern Branch, Russian Academy of Sciences, Petropavlovsk-Kamchatskii. Translated from Fiziko-Tekhnicheskie
Problemy Razrabotki Poleznykh Iskopaemykh, Vol. 34, No. 3, pp. 108–113, May–June, 1998. 相似文献
| – | - for enhancing profitability of utilization of currently exploited placers of noble metals; |
| – | - for reviewing economic effectiveness of technologically unprofitable coastal-marine placers in which finely disperse fractions of useful components are prevalent; |
| – | - for reprocessing of rejects of previously processed placers; |
| – | - for recovery of platinoids and gold from bedrocks. |
3.
Paul L Younger 《Mine Water and the Environment》2000,19(2):84-97
During the 1990s, passive treatment technology was introduced to the United Kingdom (UK). Early hesitancy on the part of regulators
and practitioners was rapidly overcome, at least for net-alkaline mine waters, so that passive treatment is now the technology
of choice for the long-term remediation of such discharges, wherever land availability is not unduly limiting. Six types of
passive systems are now being used in the UK for mine water treatment:
Each of these technologies is appropriate for a different kind of mine water, or for specific hydraulic circumstances. The
degree to which each type of system can be considered “proven technology” corresponds to the order in which they are listed
above. Many of these passive systems have become foci for detailed scientific research, as part of a $1.5M European Commission
project running from 2000 to 2003. 相似文献
| – | ♦ aerobic, surface flow wetlands (reed-beds); |
| – | ♦ anaerobic, compost wetlands with significant surface flow; |
| – | ♦ mixed compost/limestone systems, with predominatly subsurface flow (so-calledReducing andAlkalinityProducingSystems (RAPS)); |
| – | ♦ subsurface reactive barriers to treat acidic, metalliferous ground waters; |
| – | ♦ closed-system limestone dissolution systems for zinc removal from alkaline waters; |
| – | ♦ roughing filters for treating ferruginous mine waters where land availability is limited. |
4.
Conclusions The results obtained here demonstrate the promise of using technogenic and concentrated condensates of hightemperature heat
carriers to perform leaching as part of the processing of copper-nickel ores. The productive solutions that were obtained
have high contents of the useful components (grams and tens of grams per liter) and could be converted to the desired end
products by proven methods [12].
The following problems should be addressed first in future research in this area:
Scientific-Research Center, Far Eastern Branch of the Russian Academy of Sciences. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 104–109, March–April, 1998. 相似文献
| – | —determination of the optimum acid composition of the leaching solution (possibly in the agitation regime), which is necessary for technical-economic substantiation of the technology and to determine the effect of the salt component; |
| – | —development or selection of a unit for laboratory study of leaching in the filtration regime; |
| – | —development of an accurate method of determining the components of interest in the productive solutions with allowance for the effect of the matrix phase and the mutual effects of the components within a broad range of concentrations |
5.
Conclusions
Institute of Mining, Siberian Branch, Russian Academy of Sciences. Translated from Fizkiko-Tekhnicheskie Problemy Razrabotky
Poleznykh Iskopaemykh, No. 6, pp. 85–92, November–December, 1998. 相似文献
| 1. | The use of excavator-power-shovels with a scoop of active operation for mining coal-saturated regions makes it possible to simplify the technology and eliminate the losses and impoverishment caused by drilling and blasting operations. |
| 2. | A method of computation based on modelling of the trajectory of the excavator scoop can reliably evaluate indices characterizing coal loss and impoverishment in the selective and selective-gross mining of seams by excavators with a scoop of active operation. |
| 3. | The selective mining of coal seams with excavators equipped with a scoop of active operation is effective when the seams are excavated in sub-benches and the dip angle of the hanging wall is within the range α=45–65° (EKG-5V0 and α+48–78° (EKG-12V). Such excavation is effective in selective-gross mining when α>50° (EKG-5V, EKG-12V). |
6.
| 1. | Analytic formulas have been derived and a method developed for modeling the control of mining manipulators with an arbitrary kinematic scheme. It is based on an analysis of the interaction of “environment-process-manipulator” subsystems. |
| 2. | The manipulator control model makes it possible to analyze and synthesize mining manipulators. With the concept of a “generalized member” one can describe in a uniform fashion any manipulator interpreting it as a combination of generalized members subjected to certain design constraints. |
| 3. | The analysis of the interaction of “environment-process-manipulator” subsystems is illustrated by the process of building up a layer of sprayed concrete. Robotization is shown to be a way for improving the efficiency of mining, crucial for operations at great depths. |
7.
| 1. | With low-temperature plasma it is possible to create facings in soft rocks covering the entire working perimeter in a short period of time. |
| 2. | Field tests of facing models show them to have a sufficient carrying capacity and resistance to dynamic as well as static loads. |
| 3. | Laboratory tests of specimens from thermally reinforced clay rocks determined the dynamics of the variation of their strenth characteristics as a function of the speed of loading. |
8.
| 1. | The technical parameters of coals of the grades K and K2 have been studied during working of the excavation pillar by eastern long-wall faces 4 and 5. |
| 2. | Statistical characteristics of variation series were obtained. |
| 3. | Maps of isolines representing the “principal relief forms” have been compiled, which describe the regularities of distribution of the technical parameters. |
| 4. | The variations of these parameters were examined in three directions relative to the axis of the well used for multiple hydraulic treatment of a predegassed seam. |
9.
| 1. | A model of breakage mechanism and dust yield kinematics is suggested describing the fracturing of permafrost rocks in terms of the theory of brittle breakage of materials. |
| 2. | The mechanism of dust yield in bore hole drilling and other mining operations suggested in this paper will help introduce efficient methods for dust suppression at subfreezing temperatures in operations involving breakage of perennially frozen rocks. |
| 3. | A further, more profound study of dust ejection velocity v2 will help develop a method for dust suppression at the site of its origination. |
10.
Calculating the aerogas dynamics of chamber-like mine workings on the basis of mathematical modeling
| 1. | The sufficiently high reliability of the standard (k-ε) model for the Reynolds-stress in calculating the velocity field in plane chamber-like mine workings has been demonstrated. | ||||
| 2. | A version of the velocity-field calculation in plane chambers by the Smagorinskii model has been proposed, using the (k-ε) model in the preliminary stage, so as to permit considerable reduction in computer time. | ||||
| 3. |
The most rational finite-difference schemes for approximation of the advection term in the turbulent-diffusion equation when
estimating the air transfer in plane chamber-like workings have been recommended:
|
||||
| 4. | It is shown that scheme V (Table 2) has high schematic viscosity in a nonuniform velocity field, and therefore cannot be used to calculate flows in chambers with complex geometry. | ||||
| 5. | Using the numerical modeling of the physical fields (air velocity and impurity concentration) in a ventilated volume proposed here permits the determination either of the time to achieve the maximum permissible concentration with specified contamination-source intensities and air flow rates or the air flow rate required in a specified ventilation time. |
11.
Conclusions
Mining Institute, Siberian Branch of the Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 72–77, July–August, 1998. 相似文献
| 1. | It was found experimentally that the natural mineral brucite has anomalously high sorption properties in relation to ions of heavy metals in an aqueous medium. |
| 2. | A comparative evaluation of the sorption properties of brucite and well-known natural zeolites demonstrates the clear technological advantages of brucite. |
| 3. | This article is intended to be the first of a series of reports on a new class of natural sorbents. Detailed and comprehensive study of these materials will help clarify the main features of the mechanism of sorption on natural sorbents and significantly broaden the range of practical application of brucite as an active sorbent in technologies developed for the purification of natural and process water. |
12.
| 1. | Electromechanical regime observations in North Ural bauxite deposits can be used to evaluate the transcritical strain in rocks, such as loosening or pillar breakage under long-term loads. |
| 2. | In conditions where no discontinuities of rocks in the peripheral zone of workings are observed, electrometric technology can evaluate moisture content variations. |
| 3. | With the existing technology, it is impossible to estimte elastic strain by electrometric measurements in North Ural bauxite deposits. |
13.
Conclusions
Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, Vol. 34, No. 3, pp.101–107, May–June, 1998. 相似文献
| 1. | The ultimate size of bubbles in a flotation cell is an outcome of competing processes: coalescence of bubbles and adsorption of the surfactant on their surface. |
| 2. | Formation of highly developed initial interface due to breakup of the gas phase is an indispensable condition for stabilizing bubble size at a lower size level. |
| 3. | The optimal method of frothing agent injection (for stabilizing bubble size) into the flotation cell is to inject it into the air phase as vapors or aerosols. |
14.
15.
| 1. | A new model is suggested with simple techniques representing the dynamic behavior of an assembled support system at intersections of horizontal mine workings. Plastic behavior of the material at the conjugation points of structural elements is taken into account. |
| 2. | Equations systems are formulated to calculate the behavior of a support system sustaining static and dynamic rock pressures. |
| 3. | In case of a dynamic impact upon the support system at a conjugation, the greatest strength is attained when the rigidity of the external medium is higher than that of the medium filling the space between the support systems of the individual workings. |
| 4. | When a plane wave acts upon the support system at the conjugation, the internal support system removed from the wavefront at the initial time is especially susceptible to breakdown. |
| 5. | Support systems interact not only in terms of vibration amplitude but also vibration frequency and form. The influence of internal support systems upon the external support system is particularly strong. |
16.
| 1. | It is recommended to drive a slot heading with formation of lead faces in the near-wall areas followed by the breaking of the pillar remaining in the middle part of the working. The lead face should be 10–20 mm wide. The pillar exposure degree should be 1.15–1.55. |
| 2. | The performance of the slot formation process Π∼A3/2n, where A is a unit stroke energy and n is the stroke frequency. Therefore, it is more efficient to increase the energy of a single stroke rather than the stroke frequency. |
| 3. | The optimum criterion for the parameters of the impact system with the electro-mechanical drive is the maximum value of the ratio A3/2n. |
17.
| 1. | The expressions, which are confirmed experimentally, for establishing the possibility of thermal exfoliation of materials and for selecting the appropriate heating parameters, are important for designing and improving the equipment and technology for thermal treatment and disintegration of materials and also for predicting the appropriate field of application. |
| 2. | It has been established that the temperature of the surface is determined by the properties of the material and the heating conditions. The temperature limits, which depend only on the properties of the material, have been established. |
18.
| 1. | A working and a rock mass around it may be defined by one dimensionless parameter λ≥0. This parameter predetermines the behavior of the rock mass with any changes of mine pressure and support resistance. |
| 2. | With 0≤λ<1 prediction of the behavior is clear: Reaction of the rock mass to any changes in mine pressure and support resistance will have a stable character. |
| 3. | If λ>1 then stability for the reaction is only retained up to a certain critical condition. Parameters of the critical condition depend on mine pressure, the degree of weakening at contacts between blocks, geometrical dimensions and elasticity moduli. With a changeover through the critical condition there is uncontrolled dynamic release of potential elastic energy for the rock mass. |
19.
| 1. | The influence exerted by the elongation and embedment parameters of hole charges on funnel dimensions, burst velocity, and the shape of the dome is investigated experimentally. It is shown that depending on the reduced blast depth, charge elongation may either increase or decrease the burst effectiveness as compared with the detonation of a concentrated charge. |
| 2. | The use of hole burst charges becomes more effective only at sufficiently large blast depths, when the burst volume produced by concentrated charges begins to decrease. |
| 3. | A relationship for the selection of optimal embedment and elongation parameters for hole charges, which are required to obtained the maximum burst volume in sandy soil is established. In this case, the relative length of stemming increases with decreasing ratio of charge length to diameter. |
20.
| 1. | The authors show the dependence of the electrochemical properties of magnetite on the thickness of the layer removed from the specimen surface; this is of scientific interest, because the results obtained enable one to determine the effective conditions for preparation of solid electrolytes and to refine the experimental procedure so as to obtain reproducible data. |
| 2. | The variation of the magnetite electrode potential with the pH of the medium practically follows the same pattern as that characterizing magnetite-hematite equilibrium. |
| 3. | Addition of sodium oleate shifts the electrode potential toward the more negative region as a result of adsorption of the flotation reagent, the maximum change in potential being observed at pH 6–7, which also corresponds to maximum flotability of magnetite. |