The Experts below are selected from a list of 2541 Experts worldwide ranked by ideXlab platform

Chi F Peng - One of the best experts on this subject based on the ideXlab platform.

  • continuous treatment of textile wastewater by combined coagulation electrochemical oxidation and activated sludge
    Water Research, 1996
    Co-Authors: Chi F Peng
    Abstract:

    Treatment of text wastewaters from a large dyeing and Finishing Mill by a continuous process of combined chemical coagulation, electrochemical oxidation and activated sludge treatment is investigated. The experimental results are assessed in terms of COD and color (turbidity) reductions to determine the overall treatment efficiency of the combined process. Operating variables, such as the wastewater flow rate, conductivity, pH, applied current and amount of polyaluminum chloride (PAC), are explored to determine their respective effects on the efficiency of the electrochemical oxidation of the textile wastewater. Optimum operating range for each of those operating variables are experimentally obtained. Economic evaluation of the combined treatment method indicates that it is highly competitive in comparison to the conventional treatment method practiced in the textile industry.

  • Treatment of textile wastewater by Fenton's reagent
    Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 1995
    Co-Authors: Chi F Peng
    Abstract:

    Abstract Treatment of textile wastewaters from a dyeing and Finishing Mill by Fenton's reagent is investigated. The experimental results are assessed in terms of COD and color (turbidity) reductions to determine the treatment efficiency of the Fenton's process. Operating variables, such as the pH, amounts of H2O2 and FeSO4, time of Fenton's treatment and amounts of polyaluminum chloride (PAC) and polymer, are explored to determine their respective effects on the efficiency of the Fenton's oxidation of the textile wastewater. Optimum operating range for each of those variables are experimen‐tally obtained. The operating ranges of those were found to be different from those of dye waste‐water containing only single dye component. The treatment of Fenton's reagent was found to be rather effective with an efficiency of COD removal of up to 80%.

Cheol Jae Park - One of the best experts on this subject based on the ideXlab platform.

  • new tension control at the head of strip in hot strip Finishing Mill
    Journal of Materials Processing Technology, 2008
    Co-Authors: Cheol Jae Park, Cheol I Hwang
    Abstract:

    In this paper, a new tension control scheme is proposed to diminish the width shrinkage at the head of the strip in the hot strip Finishing Mill. The proposed control scheme is applied before the looper control starts and is composed of three main parts. First, the correlation between the width shrinkage and the current difference of the main motors is analyzed. Second, the tension is calculated from the current difference between the two neighboring stands. Third, the speed of the main motor is controlled by the speed difference between the output of PI controller and the reference speed. It is shown through the field test of the Kwangyang no. 1 hot strip Mill of POSCO that the width shrinkage is greatly decreased by the proposed control scheme.

  • direct width control systems based on width prediction models in hot strip Mill
    Isij International, 2007
    Co-Authors: Cheol Jae Park, Wook Hyun Kwon
    Abstract:

    In this paper, a width control system is proposed to obtain the desirable width margin of a strip in the rolling process of the hot strip Mill. A simplified FEM (Finite Element Method) based width prediction model (WPM) is developed to compute the width spread at each stand. A neural network based error correction model (ECM) is also introduced to compensate for modelling errors from the simplified FEM based WPM. Input variables for the neural network model are chosen by using the hypothesis testing. In addition, the width control scheme using the simplified FEM based WPM and the neural network based ECM is proposed to achieve the desired width margin in the Finishing Mill. It is shown through the field test of the Pohang no. 1 hot strip Mill of POSCO that the performance with respect to the width margin is greatly improved by the proposed width control scheme based on two models.

  • Development of high performance looper control system for hot strip Finishing Mill
    Proceedings of the 5th Biannual World Automation Congress, 2002
    Co-Authors: Cheol Jae Park, Seung Gap Choi
    Abstract:

    This paper presents the design method of the new controller for looper system in hot strip Finishing Mill. Looper response time is related to the performance of the tension control to reduce the delivery width error. The quality of the hot strip product, especially width deviation at the head of the strip, is greatly influenced by the precision of tension control. In this paper, a new fuzzy PID control system is designed to obtain the fast looper angle response and the high control precision. The computer simulation to verify the performance of the new controller is executed. From the results of the simulation, the tension can obtain better performance than that of the conventional PID.

  • Development of fuzzy PID control system for hot strip Finishing Mill
    IECON'01. 27th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.37243), 2001
    Co-Authors: Cheol Jae Park, Seung Gap Choi
    Abstract:

    Presents the design method of a controller for a looper system in a hot strip Finishing Mill. Looper response time is related to the performance of the tension control to reduce the delivery width error. The quality of the hot strip product, especially width deviation at the top of the strip, is greatly influenced by the precision of the tension control. In the paper, a fuzzy PID control system is designed to obtain the fast looper angle response and the high control precision. Computer simulation to verify the performance of the new controller is executed. From the results of the simulation, the tension can obtain better performance than that of the conventional PID.

W Fuchs - One of the best experts on this subject based on the ideXlab platform.

  • Advanced treatment of textile wastewater towards reuse using a membrane bioreactor
    Process Biochemistry, 2006
    Co-Authors: Marina Brik, P. Schoeberl, B. Chamam, R. Braun, W Fuchs
    Abstract:

    The aim of this work was to quantify the performance of a membrane bioreactor (MBR) for the treatment of textile wastewater, and to investigate its capability to achieve a water quality meeting reuse criteria. A laboratory-scale MBR unit was fed with textile wastewater originating from a polyester Finishing Mill. Removal capacity was examined at VLRs ranging between 0.35 and 3.6 g/(l day). In addition, the effect of nutrient addition was studied. COD removal was found to vary between 60 and 95% with reduced COD levels at lower VLRs tested. Nutrient addition slightly enhanced effluent quality. Sludge yield obtained were between 0.01 and 0.1 gMLSS/gCODremoved. At similar sludge loading rates specific sludge production rates were approximately 50% higher when nutrients were added. A distinct relationship between sludge growth and colour removal could be observed. Above an sludge growth rate of 0.3 g/(l day), colour removal was above 87% for all wavelengths examined. If reuse of MBR treated wastewater is intended, additional polishing steps must be considered as MBR effluents did not reach the required quality for water reuse. In order to upgrade MBR effluent, nanofiltration as a post-treatment was suggested. © 2006 Elsevier Ltd. All rights reserved.

J J Yi - One of the best experts on this subject based on the ideXlab platform.

  • hot strip width control method by using looper tension measuring system in Finishing Mill
    Journal of Materials Processing Technology, 2001
    Co-Authors: W K Hong, Young Hoon Moon, J J Yi
    Abstract:

    Abstract A high precision hot strip width control method has been developed in this study by applying an interstand looper tension measuring system at the Finishing Mill stands. As the width deviation of hot rolled steel strip is closely related to abnormal increase in the interstrip tension, an on-line measuring device of looper tension and a data analyzing system were developed in this study. To determine dominant factors that will cause local width shortage, the logged data sets of bar width, bar thickness, looper tension, and strip thickness along the strip length were correlated with the data set of strip width change. With the result of the correlation analysis, existing sequence control logic and parameters for looper actuator were modified for strip width quality and the gains of the looper control were refined for stable operation during the full passage of rolled strip. The on-line tension measurement and tension feedback control for the looper system, improved the strip travelling stability and reduced strip width deviation in the strip top end region.

Cheol I Hwang - One of the best experts on this subject based on the ideXlab platform.

  • new tension control at the head of strip in hot strip Finishing Mill
    Journal of Materials Processing Technology, 2008
    Co-Authors: Cheol Jae Park, Cheol I Hwang
    Abstract:

    In this paper, a new tension control scheme is proposed to diminish the width shrinkage at the head of the strip in the hot strip Finishing Mill. The proposed control scheme is applied before the looper control starts and is composed of three main parts. First, the correlation between the width shrinkage and the current difference of the main motors is analyzed. Second, the tension is calculated from the current difference between the two neighboring stands. Third, the speed of the main motor is controlled by the speed difference between the output of PI controller and the reference speed. It is shown through the field test of the Kwangyang no. 1 hot strip Mill of POSCO that the width shrinkage is greatly decreased by the proposed control scheme.