Papers by Keyword: Separation Performance

Abstract: An experiment setup was built to test the droplet separation performance of demister. Different experiments were conducted using various Polytetrafluoroethene (PTFE) meshes. Results show that the separation efficiency of demister is dependent on screen thickness, mesh count. Pressure drop increases with the increase of steam flow rate and screen thickness.

Abstract: The rank one NMF blind source separation algorithm (NMF-R1) was obtained by imposing the sparsity constraint on the fast NMF algorithm based rank one. NMF blind source separation algorithm based on least squares (NMF-LS) was obtained by using pseudo-inverse matrix. NMF-R1 algorithm was superior to the existing blind source separation algorithms based on NMF. NMF-LS algorithm had faster computation speed, but the result of decomposition was not unique. In order to further enhance the signals separated performance, crossover iteration between NMF-R1 and NMF-LS was used to getting the mixing matrix and the signal matrix, and the mixed NMF blind source separation algorithm (NMF-LR) was obtained. Simulation results show that the separation performance of NMF-LR algorithm is better than that of NMF-R1 and NMF-LS, and the computation complexity of NMF-LR algorithm is nearly the same as NMF-R1 algorithm.

Abstract: A study on the flow and separation performance of supersonic gas separator is carried out through numerical simulation and experimentation. The effect of area ratio on the separation performance under low pressure ratio has been researched. The simulation results indicate that with an increase of the area ratio AR, the intensity of the shockwave increases and the location approaches the throat; Shockwaves are absent in the diverging section of the nozzle when area ratio is 1.063 and the pressure ratio is within 1.25-1.75, which reaches the highest separation performance. The calculated and experimental results also show that the separation performance is the highest and can reach 40.82% when pressure ratio is 1.75. The calculated values are in agreement with the experimental results.

Abstract: Abstract Because of external driving, dynamic pre-cyclone separators have excellent operational performances in areas of pressure vary occasionally. In this work, a numerical model of the dynamic separator been built and the flow field is thoroughly studied. The distribution results of angular velocity show that an appropriate structure of pre-cyclone vanes is of great importance to get a relative uniform flow angular velocity field. A novel structure of pre-cyclone vanes under different separation requirements is developed and verified by a number of experiments.

Abstract: Fractionation of softwood BCTMP pulp fiber was carried out with a cylindrical hydrocyclone. Pulp fiber length characterization in different streams have been examined using FQA. The fiber length fraction density function f is calculated and the separation index H(L) is used to evaluate fiber fractionation performance for different streams, and its specific expression was formed, so the new index may be widely used in the study of the evaluation of the separation performance of the hydrocyclone.

Abstract: Inner flow field, pressure field and gas phase concentration of the gas-liquid cylindrical cyclone (GLCC) was studied and simulated with a Fluent soft pack by means of Computational Fluid Dynamics (CFD). Distribution characteristics of pressure drop and velocity field of the GLCC reveal that the inlet position and the outlet diameter of overflow can affect its separation performance. Low pressure drop and high separation efficiency can be obtained by designing the inlet position and the overflow tube diameter.

Abstract: Electrodeionization (EDI) is being applied more and more to treat wastewater containing heavy metal ions, especially for electroplating rinsing wastewater. The effects of feed water conditions including concentration, pH and temperature on the performance of EDI process for removal of Ni2+ from dilute synthetic wastewater were investigated systematically in this paper. It was found that the dilute resistivity of the EDI module descended from 1.5-2.8MΩ•cm to 0.36-0.45MΩ•cm while the influent Ni2+ concentration increased from 45 mg•L^-1 to 63mg•L^-1. Existence of some H+ in feed water would push the stack current up. An increase in temperature of feed water would facilitate the ion exchange and diffusion and thus promote mass transfer. It was indicated that feed water conditions had a significant effect on separation performance of EDI process for treating dilute solutions containing heavy metal ions. Pure water production could be accomplished and water reuse could be realized via EDI technology by appropriately restricting feed water conditions.

Abstract: Applicable configuration alteration of the electrodeionization （EDI）process commonly for pure water production was carried out to treat dilute nickel wastewater in this paper. The effects of major operating parameters such as applied voltage, dilute and concentrate stream flow rates on the performance of EDI process were investigated systematically. The results showed that, with the feed water containing 50mg·L^-1 Ni²⁺ and pH of 5.7, the dilute resistivity of the EDI could reach higher than 1.0MΩ·cm which gave a Ni²⁺ rejection more than 99.8% while the Ni²⁺ was concentrated as high as 1564mg·L^-1 in the concentrate stream by optimizing the operating parameters. It was indicated that pure water production and concentrating of heavy metal ions could be simultaneously accomplished via EDI technology just in one process, valuable heavy metal and water resource could be recovered as well.

Abstract: The aim of the present work was to study the effect of properties of ion exchange membrane on separation performance of electrodeionization (EDI) process for removal of nickel ions from dilute heavy metal solutions. It was shown that the properties of ion exchange membrane had a significant effect on removal of nickel ions. With feed water containing nickel ions at the concentration of 55mg•L^-1, the nickel ions concentration of dilute stream was lower than 0.5mg•L^-1 and the nickel rejection was greater than 99% when using EDI membranes, while that was in the range of 2.48-3.55mg•L^-1 with conventional heterogeneous ion exchange membranes. With optimum ion exchange material and operating conditions, EDI would be a very interesting and innovative technology for the treatment of dilute heavy metal solutions.