Time filter

Source Type

Zhai L.,University of Science and Technology of China | Zhai L.,Nanjing University of Science and Technology | Zhong Q.,Nanjing University of Science and Technology | Wang X.,Pingdingshan Tianan Coal Mining Co.
Advanced Materials Research | Year: 2012

Experiments were performed on the packed tower with 150mm diameter and 2800mm high to study the wet flue gas desulfurization continuously. The results shows that the suitable conditions for the SO2 absorption process of 0.3mol·L-1 ethylenediamine/phosphoric acid and ethylenediamine/boric acid solutions: pH value was 6.0∼7.0, liquid-gas ratio was 0.82L·m-3. The import SO2 concentration and the flue gas flow were separately at 500×10 -6∼3100×10-6 and 110m3·h -1∼150m3·h-1, the desulfurization efficiency exceeded 97%. Under the same conditons, ethylenediamine/boric acid has a better desulfurization and was more suitable for the flue gas desulfurization in a wider fluctuation. © (2012) Trans Tech Publications, Switzerland.

He Z.,Zhengzhou University | Li D.,Zhengzhou University | Cao L.,Pingdingshan Tianan Coal Mining Co. | Yang X.,Zhengzhou University
Open Mechanical Engineering Journal | Year: 2014

In the process of machining rectangular microchannels, severe friction occurs between the chip and the side face of the machined microchannel. The cutting forces have great effect on the miniature cutting tool. Thus, 3D FEM is adopted to study the cutting forces. The influences of the depth of the machined microchannel t, the cutting depth ac, the cutting width aw, the rake angle γ。 and the cutting speed v on the cutting forces are investigated. Results show that the main cutting force Fz and the thrust force Fy increase with the increase of t, ac and aw and have no obvious change with v. Moreover, Fz decreases and Fy increases as γ。increases. © He et al.

He Z.,Zhengzhou University | Li D.,Zhengzhou University | Cao L.,Pingdingshan Tianan Coal Mining Co. | Tang Y.,South China University of Technology
Materials and Manufacturing Processes | Year: 2015

A new method for fabricating CCMPMPs, namely multi-cutter milling, is proposed and the fabrication principle is discussed. Then, a study of three microchannel parameters, the microchannel depth Hc, width Wc, and interval Ws, and two CCMPMP parameters, the porosity P and the total surface area per unit volume SV, is presented. Furthermore, 3D FEM has been adopted to study the effective stress distribution, the metal flow velocity distribution, and the cutting forces. The results show that CCMPMPs can be successfully machined. Hc, Wc, and Ws can be controlled by the radial depth of cut ae, the slotting cutter thickness Et, and the gasket thickness Eg, while P and SV can be changed by adjusting Hc, Wc, and Ws. Moreover, as ae increases, the average resultant force increases, and the friction between chip and the side face of the machined microchannel, and between chip and the rake face, plays an increasingly important role in it. © 2015 Taylor & Francis Group, LLC.

He Z.,Zhengzhou University | Li D.,Zhengzhou University | Cao L.,Pingdingshan Tianan Coal Mining Co. | Tang Y.,South China University of Technology
Journal of Enhanced Heat Transfer | Year: 2013

In order to enhance the heat transfer performance of a plate heat exchanger, porous copper fiber sintered sheets (PCFSSs) with a three-dimensional (3D) network structure has been developed. Slim copper fibers are manufactured with a new type of multi-tooth tool. Then, they are pressed and sintered in a designed mold to produce the PCFSSs. In addition, the heat transfer performance and the pressure drop of the plate heat exchanger are investigated experimentally. The results show that copper fibers with a rough surface can be manufactured efficiently. PCFSFs with a 3D network structure can be successfully machined. Moreover, PCFSSs with porosity of 70% nearly quadruple the heat transfer performance and PCFSSs with porosity of 90% are optimum, considering both the heat transfer performance and the pressure drop. © 2013 by Begell House, Inc.

Teng Y.-H.,China Coal Technology and Engineering Co. | Wei X.-J.,Pingdingshan Tianan Coal Mining Co. | Tang Z.-X.,China Coal Technology and Engineering Co. | Wang X.-Y.,Pingdingshan Tianan Coal Mining Co. | Yi S.-H.,China Coal Technology and Engineering Co.
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

To solve the problem of huge coal protective pillar induced by new shaft in deep depth area, the methods for the design of small-sized safety pillars were proposed based on the result of field experiment, numerical simulation calculation and theoretical study. The safe pillars were so designed as to be able to effectively reduce the deformation of the shafts and ensure the stability and symmetry of pillars. Force and deformation law of new shaft protected by small-sized safe pillar was analyzed by numerical simulation, some problems needing attention in the shaft protection were proposed. A systematic study was made on the techniques for increasing the shafts' deformation-resistant capability through making overall planning and using rigid and flexible structural measures to effectively absorb and resist the movement and deformation of strata. As evidenced by practical result for the protection of a pair of new anti-deformation downcast and upcast shafts at the No. 4 Coal Mine under Pingdingshan Tian'an Coal Mining Co., Ltd., the design of the safe pillars and the anti-deformation techniques adopted for protection of the 2 shafts have achieved remarkable techno-economical effects.

Discover hidden collaborations