| Along with economy developing continuously and fleetly, the conflict of supply and need of mineral resource is severity increasingly in China, and its depending degress on foreign country is more higher, which will threaten the safety of national resources. Meanwhile the serious shortage of mineal resource and the idling of valuable element in solid waste forming vivid contrast, it is extremely urgent to exploit redeposit resource—"Artificial Deposit", such as dump. Although heap leaching is an ideal method for processing poor resources, example as low grade ore, out-of-list ore, waste rock and tailings, its application and popularization are limited in dump, because the dump has some disadvantages, such as thicker heap, complex topography, higher clay content, bigger average particle of grain and lower grade as well, which cause poor permeability, low leaching rate and lixivium concentration, poor bacterial activity, and long leaching period and higher product cost. So, it has important significant to study the technologies for accelerating leaching in dump for relaxing the conflict of supply and need of mineral resouyrce and ensuring the safety of national resources.This thesis focuses on studying the accelerating leaching mechanism and new technology of copper mine dump, taking the dump leaching plant of Dexing Copper Mine as an engineering example. It is supported by three projects that are 973 Program-National Basic Research Program of China "The Multifactor Strong Relating in Leaching System" (No.2004CB619206), National Science Fund for Distinguished Young Scholars of China "The Study on Dynamics of Multilevel Seepage and Mass Transfer in Multiphase Granular Medium" (No.50321402), and National Fund for Creative Research Groups of China "The Basic Research of Bioleaching Sulphide Ore" (No.50321402).Aimed at the problems existed in copper mine dump, with site investigation, indoor experiments, theoretical analysis, the paper analyzed the key factors. Taking seepage mechanism and new spreading and collecting liquid mode of dump as breakthrough, and compromising temperature control and gas transportation, it carried out the studies about momentum transfer, heat transfer and mass transfer rule in solution flow, and integrated theoretical achievements into the new technology of dump leaching finally, which has great applying potential.The main works that the thesis finished are as follows:(1) It was discoveried that seepage effect of level seeping is superior to vertical one obviously in heterogeneous body, and the spraying inside dump improve largely uniformity of solution in dump. It has anisotropism in heterogeneous body, and its anistotropy factor is between 63 and 155, which is 10 to 100 times of homogeneous body. The seepage factor of spraying inside dump is bigger than that of spraying on surface of heterogeneous body, where the ratio of them is 1.42 to 3.02. The conclusuon designates way to solve poor permeability, and the new technology should adopt the mode of spraying inside dump.(2) It was first to experiment on column leaching of primary copper sulphide ore with all-around accelerating leaching measure, and offered technical prototype for accerlating leaching in dump. It adopted together with four measures in synthetical acclerating leaching, which is domesticated bacterial, air feeding, temperature controlling, mass flow. The temperature inside column is 5.8℃high than one of conventional leaching column, the bacterial concentration is upward trend all along, and Cu leaching efficiency rise 40.5%. The leaching rate of synthetical acclerating leaching is high than one of single accerlating measure, such as air feeding and temperature controlling, which the ratedetermining step transform internal diffusion from surface chemical rate with the study on copper leaching dynamics. In the meanwhile, the leaching efficiency of copper is in direct proportion to temperature, air-flow rate and spraying intensity, which prove the mode of mass flow leaching being favorable for heightening leaching efficiency. In the course of leaching, the granular seepage coefficient drops gradually with time, and the influence of chemical jam is greater than that of mechanical jam, which Fe precipitation is key factor to decide if the leaching is succeed or not.(3) Based on potential function and its superposition principle, It was opened out the seepage law under the different seepage states in dump, and indicated that the flux unit area of two-point mode is maximum. It brought forward the three principle for optimal hole network, and erected the relation of hole network parameter and radius influened, and deduced that the formulas of the radius influenced and solution flux of unit area in different flow states, and it has priority to adopt the mode of cube under the same conditions. Reference for empirical formula of coare grained soil seepage, it was expatiated that the cause of permeablility exasperated is a level aquiard forming after granular compacted, the seepage state belongs to tranition flow, the destructional form of seepage is piping, and educed the conclusion that the new technical is favourable to enhance slope stability in dump.(4) Recur to thermodynamic principle, it studied on mechanism of bacterial leaching, and was clarified that the direct action holds the leading status in copper leaching. The leaching reaction are exothermic if bacterial act directly, and that are endothermic if bacterial act indirectly. The free energy is lower if sulphide ore act with oxygen, and sulphide ore act prioritically with cxygen under the same condition, but higher temperture makes against bacterial direct action. The range of electic potential if sulphide ore act with oxygen is lower than that with ferric sulfate, and oxygen is excelled to ferric sulfate as oxidant.(5) Utilizing the forced convection principle of fluid in porous medium, it opened out the the heat conduct law in dump, which provided theretical guiding to temperature controlling for accelating leaching. Basis on heat flux equilibrium theory, it established the conservation formula of exotherm and heat dissipated, which settles base on fluid transfering heat in dump. By enthalpy principle and the main associated mineral, it derivated heat flow formula of leaching reaction, which indicates heat flux from pyrite leached and sulfur oxygened outclass one from chalpyrite. With natural-convection heat transfer, it analyaed the heat disspating from dump to atomsphere, which is less ratio of totall heat flux and ignore. It estimated ore heat absorption by matter specific heat theory, which fits with observational data in field basically. Use for multiparticle swarm forced converction heat transfer theory, it elicited the heat exchange correlative formular, combining with Dexing Copper Mine data, it was a witness to heat transfer is feasble by solution, which heat adjusted by solution accounts for 59.6%～67.4% of the total heat, and temperature controlling in summer is difficult than in winter.(6) It discussed the oxygen transmitting path, probed into profitably oxygen transmitting theory under gas transferring theory. The dissolve oxygen only maintains bacterial self breeding in solution, but can't satisfy the oxygen demanded in chemical reaction. Depending on artifical ventilation into dump, forming a great deal of bubble, oxygen dissovlling and transferring is promoted by high press instant as bubble crumble and fall. The pyrite is the main mineral competing for oxygen in leaching copper ore, and oxygen consumption increases sharply with pyrite increasing. By engineer example estimating, it proved air feeding for accelating leaching is feasible, which air constumption unit volume ore is only 0.77 m~3/m~3, and articial forcing oxygen supply realize easily on basis of available facilities.(7) On the basis of the above accelerating leaching mechanism study, it put forward the new craft of dump leaching accelerated. The new technology is coordinating process of spraying on surface and inside dump, which the coverage area of spraying on surface accounts 15% in height and the mode of spraying inside dump undertakes the most part of metal recovered. Air supplying and temperature controlling articially become organic composition of pipe-pouting method, and continuous culture bacterial technology intelligentized is key to accedating leaching technique. Based on actual production data of dump leaching plant in Dexing Copper Mine, it forecasted the main econo-technical indicators of the new technics. Although the new technology needs higher production cost, its gross profit is improved by 11% than that of the old one because leaching rate is enhanced, so the overall economic benefits are better.
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