China Enfi Engineering Corporation

Beijing, China

China Enfi Engineering Corporation

Beijing, China
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Xia C.,Tongji University | Song Y.,Tongji University | Tang Z.,Tongji University | Song Y.,China Enfi Engineering Corporation | Shou C.,Nanjing Southeast University
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2012

Real rough joints profile has been rebuilt by PFC 2D(particle flow code in 2 dimensions) successfully, and a series of PFC 2D numerical simulation direct shear tests have been done to obtain its shear behavior. We can observe the failure process from the viewpoint of mesomechanics through PFC 2D. The damage process of asperities on rough surface and the corresponding micro-fracture development can also be monitored in the numerical direct shear tests and these can be treated as a supplement of model tests. Macroscopic deformation of the sample is formed by the accumulation of mesoscopic shear cracks;and the shear failure area of rock mass mainly grows on the climbing slope of joint, where is the shear stress focus area as well. As the peak shear stress appears, the number of shear cracks is increasing quickly, when the failure of rough rock joint is most significant. According to the numerical tests, the results between model tests and numerical tests fit well; so real rock-joint model tests can be partly replaced by PFC 2D numerical tests, which can become a way for forecasting the shear strength of real rock joints. The problem that the topography of real rough rock joints is hard to be restored has been solved by the numerical simulation method.


Liao Y.,Xi'an Jiaotong University | Zhang P.,China Enfi Engineering Corporation
Mechanism and Machine Theory | Year: 2010

The precession behavior of an unbalanced rotor-bearing system with anisotropic supporting stiffness is analyzed. The result shows that the probe-orientation-related problem is still unsolved in the holospectrum technique based rotor balancing method. The deficiency of the balancing object of this method now in use, the Initial Phase Vector (IPV), sometimes makes the description or evaluation of rotor balance state unclear. Necessary modification to this method is made in this paper. A compound balancing object comprised of the magnitude of the major axis and the Initial Phase Angle (IPA) of the precession orbit is presented to replace the IPV as the rotor unbalance response. The amount and angular location of the mass unbalance can be determined precisely by the magnitude of the major axis and the IPA, respectively. Since the isotropic assumption is no longer a prerequisite and the evaluation of the mass unbalance amount is independent of the probe orientation, optimal result then can be ensured. The experiment and real application case verify its capability and feasibility. © 2009 Elsevier Ltd. All rights reserved.


Dou R.,University of Science and Technology Beijing | Wen Z.,Beijing Key Laboratory for Energy Saving and Emission Reduction of Metallurgical Industry | Zhou G.,China ENFI Engineering Corporation
Applied Thermal Engineering | Year: 2016

A 2D axisymmetric inverse heat-conduction model based on the Levenber-Marquardt method was built. The equivalent Nusselt number Nuequ of air jet impinging on a stainless steel plate with finite thickness were obtained. Radiant heat transfer is significant when the temperature of the target plate is high, which induces the nonlinear feature of the inverse heat-conduction problem. The results of the experiments and the inverse analysis provide the following findings. First, the inverse heat-conduction model is accurate. Second, Nuequ maintains a relatively small value before the onset of the air jet. After the air jet starts, however, the values of Nuequ within the stagnation zone (dimensionless radius R/Dn≤&1.0) increase dramatically, reach the peak points in the next 20s, and then remain nearly constant until the end of the experiments. Third, the radial distribution of Nu;bsubesub shows that it decreases rapidly within the region of R/D;bsubesub≤;8.0. When R/Dn exceeds 10, Nuequ appears unaffected by the Reynolds number and R/Dn. Lastly, Nuequ decreases slowly with the increase in time, which indicates that radiant heat-transfer flux decreases with target plate temperature. © 2015 Elsevier Ltd. All rights reserved.


Yang Z.,Central South University | Yang Z.,China ENFI Engineering Corporation | Rui-Lin M.,Central South University | Wang-Dong N.,Central South University | Hui W.,Central South University
Hydrometallurgy | Year: 2010

A novel hydrometallurgical method was developed to selectively extract base metal values, such as cobalt, zinc, and copper from copper smelter slag at atmospheric pressure. It involves leaching with sulfuric acid and sodium chlorate oxidant and neutralization with calcium hydroxide for better and faster filtration of the precipitate. It significantly decreases or avoids the adverse effects of silica and iron(III) oxides on recycling or extracting target value metals. Four key parameters were explored in this new approach, namely, sulfuric acid consumption, amount of sodium chlorate, reaction temperature and reaction time. Calcium hydroxide was one of most critical factors to precipitate silica and iron(III) oxides before filtration. Once all these four parameters were optimized, the overall extraction and recovery of cobalt, zinc and copper was 98%, 97%, and 89% respectively, while the extraction of silicon and iron was only 3.2% and 0.02%, respectively. This hydrometallurgical process, almost completely recovers the valuable metals of cobalt, copper and zinc from the copper smelting slag without roasting. The proposed leaching method is simple, economical and competitive to operate, so it is readily applicable in industry. © 2010 Elsevier B.V. All rights reserved.


Patent
Sichuan Chuanheng Chemical Corporation and China Enfi Engineering Corporation | Date: 2010-05-27

The present invention discloses an apparatus for thermally refining phosphorus. The apparatus comprises: a melting furnace for melting rock phosphate into melts, including a feed port and a melt outlet; and a reduction-oxidation furnace including a furnace body which gas a melt inlet, a slag outlet, and a fume outlet, and a blow gun, wherein the melt inlet and the melt outlet are in communication with each other and wherein the blow gun has an end inserted into the furnace body. The content of impurities in fumes containing phosphorus pentaoxide is low, and the phosphorus pentaoxide can be easily extracted with a high purity of the phosphorus pentaoxide and at low cost by means of the apparatus for thermally refining phosphorus according to the present invention.


Patent
Sichuan Chuanheng Chemical Corporation and China Enfi Engineering Corporation | Date: 2010-05-27

The present invention discloses a reduction-oxidation furnace for thermally refining phosphorus. The reduction-oxidation furnace comprises a furnace body and a blow gun, wherein the furnace body has a slag outlet, a fume outlet, and a melt inlet for feeding melts formed by melting rock phosphate into the furnace body and wherein the blow gun has an end inserted into the furnace body. The content of impurities in fumes containing phosphorus pentaoxide is low, the phosphorus pentaoxide can be easily extracted with a high purity of the phosphorus pentaoxide and at low cost by means of the reduction-oxidation furnace for thermally refining phosphorus according to the present invention.


Jie Y.,China ENFI Engineering Corporation
TMS Annual Meeting | Year: 2015

This paper introduces and studies systematically the Cu production of Chinese Copper smelters in recent years and in future years, as well as the technology development and CAPEX of Chinese new Copper smelters. In the paper, treatment trend on copper scraps, waste copper materials and electronic wastes are also analyzed. © Copyright 2015 by The Minerals, Metals & Materials Society. All rights reserved.


Patent
China Enfi Engineering Corporation | Date: 2016-08-10

This disclosure provides a high-temperature material conveying tank, including a tank body provided with a material cavity inside, a feed inlet at an upper part and a discharge outlet at a lower part, wherein the tank body includes a cylindrical section, a first taper section and a first connection section, the first connection section is arranged at one end of the cylindrical section and arranged between the one end of the cylindrical section and the first taper section; the first connection section is integrally formed with the first taper section, and buttwelded with the mentioned cylindrical section. The high-temperature material conveying tank of present disclosure has an advantage of good stress intensity, thereby prevents a welded joint from cracking and deforming.


Patent
China Enfi Engineering Corporation | Date: 2016-07-06

Provided are a nickel hydroxide product and its preparing method. The method includes: (a) enabling a first nickel hydroxide pulp to be in contact with sodium hydroxide, so as to obtain an alkalized pulp; (b) enabling the alkalized pulp to be in contact with a nickel sulfate solution, so as to obtain a nickel-precipitated pulp; (c) returning at least one part of the nickel-precipitated pulp to the step (a) as the first nickel hydroxide pulp, and repeating the steps (a) and (b) at least once; and (d) separating the nickel hydroxide from the rest part of the nickel-precipitated pulp.


Patent
China Enfi Engineering Corporation | Date: 2016-06-22

Provided are a method for processing a laterite-nickel ore and a method for recycling scandium. The method for recycling scandium includes steps of: extracting scandium from scandium-containing leachate with an organic extractant, so as to obtain a scandium-containing organic phase; subjecting the scandium-containing organic phase to back-extraction with a monovalent acid, so as to obtain a strip liquor; mixing the strip liquor with a precipitant, so as to obtain a scandium-containing precipitate; and calcining the candium-contained precipitant, so as to obtain scandium oxide.

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