The Chinese Journal of Process Engineering

Numerical Simulation of a Circulating Fluidized Bed Combustor on an One-dimensional Pseudo-fluid Approach

WANG Wei;LU Xu-chen;LI You-chu

. 2004, 4(5): 385-390.

Asbtract ( )

PDF (188KB) ( )

Related Articles | Metrics

A 0.2 MW fast-fluidized bed combustor at Institute of Chemical Metallurgy built in 1983 was modeled. The model was characterized by a pseudo-fluid approach, that is to say, (1) gases and solids are continuously distributed across the chamber and hence their mass balance relation could be expressed in form of differential equations; (2) flow parameters in the chamber was calculated from a pseudo-fluid model closed by the kinetic theory of granular flow, and was incorporated into the reaction and heat transfer models. The model prediction was generally in agreement with experimental evidence.

Adsorption of L-Arginine on Macroporous Strong Acidic Resins

WENG Lian-jin;GAN Lin-huo;WANG Shi-bin;HAN Yuan-yuan;LI Xia-lan

. 2004, 4(5): 391-396.

Asbtract ( )

PDF (152KB) ( )

Related Articles | Metrics

The adsorption of L-arginine on D001 macroporous strong acidic resin was investigated. The results show that the adsorption can be precisely described with the Langmuir and Freundlich equations, the equilibrium of adsorption of L-arginine by D001 resin can be reached in 30 min, and the adsorption ratio decreases with the increase in NH4Cl or NaCl concentration. pH is a parameter which obviously affects the adsorption, and the optimum pH of adsorption of L-arginine from desalted cystine mother liquor is 7~8. The breakthrough of desalted cystine mother liquor through D001 resin and elution curves were also measured, showing that the elution curve is much steeper than the breakthrough curve.

Adsorption of Thiourea Gold in Acidic Thiourea Leaching Liquor by D072 Macroporous Strong Acid Resin

HU Xiao-ling;ZHANG Sheng;GUAN Ping;ZHASNG Xin-li

. 2004, 4(5): 397-400.

Asbtract ( )

PDF (150KB) ( )

Related Articles | Metrics

The adsorption and exchange properties of thiourea gold complex by D072 macroporous strong acidic resin from a weak acid solution were investigated. The results showed that resin D072 could effectively adsorb Au(Tu)2+ ions (Tu=thiourea) at 25℃. The static saturated adsorption capacity of the resin could reach 78.95 mg/g (Au/resin). The adsorption rate was 98.4%. The loaded resin could be qualitatively eluted with 94% alcohol, 2% sulfuric acid solution and 4% water, the elution rate of thiourea gold was 96.5%. The adsorption isotherm line was of the Langmuir type. The eluted resin was regenerated with 5% Na2S2O3 solution. The adsorption capacity of the regenerated resin was uniform.

Process for Separation of Naphthenic Acids from High TAN Heavy Crude Oil of Sudan

REN Xiao-guang;QI Liang;SONG YONG-ji;REN Shao-mei

. 2004, 4(5): 401-405.

Asbtract ( )

PDF (127KB) ( )

Related Articles | Metrics

The process for extracting naphthenic acids (NA) from crude oil was proposed. In order to extract naphthenic acids from crude oil, a combined solvent system comprised of ethanolamine, ethanol, Na2SO4 and UD10 in certain critical proportions was used to facilitate selective extraction and easy separation. The optimum constituents of the solvent system are: ethanolamine 10%(w), ethanol 35%(w), Na2SO4 2%(w), and UD10 100×10-6. The optimum ratio of solvent to oil is 0.3~0.5. Other extraction factors including extraction temperature, blender rotational speed, phase splitting time and reaction time were also discussed in details. Experimental results indicated that the method could efficiently prevent the problems of emulsification and high loss of oil aroused in the process of alkaline treatment or the high ratio of solvent/oil and large amount of solvent recycling in the process of ammonium treatment. More than 70% of the petroleum acids could be removed. The purity of NA was qualified enough to be used in industry. In addition, the extraction process is suitable for separating not only whole crude oil, but also its certain fractions.

Exergy Analysis of TDA Refining Process

LI Yu-gang;LI Xiao-ming;QIANG Guang-ming;ZHENG Shi-qing;HAN Fang-yu

. 2004, 4(5): 406-409.

Asbtract ( )

PDF (214KB) ( )

Related Articles | Metrics

In order to reduce energy consumption, thermal analysis is applied to a TDA refining process, in which both heat equilibrium and exergy analysis methods have been used. The analysis shows that the exergy analysis method is more instructive than the heat equilibrium analysis. Through exergy analysis, the key subsystems that consume more energy than others are found and improvement is suggested, and the exergy consumption per ton of product may be reduced by 45%. The result of cost analysis shows that the suggested improvement will bring about more economic profit.

Effect of Reaction Pressure on Synthesis of Methylchlorosilane

LUO Wu-xi;WANG Guang-run;WANG Jin-fu;JIN Yong

. 2004, 4(5): 410-414.

Asbtract ( )

PDF (198KB) ( )

Related Articles | Metrics

The effect of reaction pressure on reaction activity and selectivity of dimethyldichlorosilane (DDS) in direct synthesis process has been investigated experimentally. The experimental results show that the reaction rate of this catalytic reaction increases with the increase of reaction pressure, with an almost constant silicon conversion. However，the selectivity of DDS will decline when pressure rises. This is brought by that the main and secondary reactions obey different reaction orders with regard to pressure. So high pressure is inadvisable and a pressure of below 0.3 MPa is recommended for practical production. The relation between reaction selectivity and operation pressure is regressed to predict the selectivity under the pressure range from 0.1 to 0.5 MPa. Furthermore, it was found in experiments that the influence of pressure fluctuation on the reaction performance is reversible. This demonstrates that the variation of pressure only changes the species concentration of gaseous phase and does not affect the properties of the contacted mass. Thus the pressure fluctuation in short time is reversible.

Synthesis and Characterization of Poly(aryl ether sulfone ether ketone ketone) Random Copolymers Prepared by 2,2￠-6,6￠-Tetramethyl-4,4￠-Diphenoxydiphenlysulfone, Diphenether and Terephthaloyl Chloride

CHEN Lie;SONG Cai-sheng;WEN Hong-li;DONG Yong-fen;LIU Xiao-ling

. 2004, 4(5): 415-419.

Asbtract ( )

PDF (264KB) ( )

Related Articles | Metrics

A novel series of random copolymers composed of poly(aryl ether sulfone ether ketone ketone) were prepared by low temperature solution polycondensation of 2,2￠,6,6￠-tetramethyl-4,4￠-diphenoxydiphenylsulfone (o-M2DPODPS), diphenether (DPE) and terephthaloyl chloride(TPC) in 1,2-dichloroethane in the presence of AlCl3 and DMF. The copolymers were characterized by 1H-NMR, FT-IR, DSC, XRD, TGA, etc. The results show that glass transition temperature increases with the increasing ratio of o-M2DPODPS/DPE, the inherent viscosity, melting temperature and crystallinity of copolymers decrease with the increase of the ratio of o-M2DPODPS/DPE. The solubility of the copolymers is improved greatly, while the copolymers still exhibit excellent thermostabilities and solvent resistance. As a latent functional group, the bis(o-methyl) pendant can be converted to bromomethyl, aldehyde or carboxylic acid groups. The high-performance polymers with functional groups on the polymer main chain for specialty applications such as membrane materials can be prepared by functionalization reactions.

Preliminary Exploration on Dressing and Smelting of Refractory Gold Ore by Supercritical Water Oxidation

MA Cheng-yu;JIANG An-xi;PENG Ying-li;YANG Jian-jun

. 2004, 4(5): 420-423.

Asbtract ( )

PDF (130KB) ( )

Related Articles | Metrics

The preliminary exploration on dressing and smelting of refractory gold ore by supercritical water oxidation(SCWO) was investigated. When oxidation reaction time is 10 min, temperature is 550oC and pressure is 25 MPa, the recovery rate of refractory gold ore can be from 35% or less to 92.8%, organic compounds can be oxidized to carbon dioxide and water, sulfur can be oxidized to sulfate and be sedimentated. Although arsenic is oxidized to arsenic trioxide, it dissolves hardly into supercritical fluid and is sedimentated too. Effluent water is clear, with a quality meeting the national integrated wastewater discharging standard. There is no pollutant in effluent air，it is promising for cleaner dressing and smelting of refractory gold ore.

Optimization of Cementing Materials Used in High-temperature Oxidation-resistance Ceramic Coatings for FeCrAl-matrix

ZHOU Jian-er;LI Jia-ke;JIANG Wei-hui

. 2004, 4(5): 424-428.

Asbtract ( )

PDF (379KB) ( )

Related Articles | Metrics

The effect of cementing materialsˊperformance on the properties of high-temperature oxidation-resistance ceramic coatings has been studied in detail through the analysis of oxidation-resistance and thermal shock-resistance of the coatings. These coatings were fused at 1300℃ in air, and applied to FeCrAl-matrix. The high-temperature cementing materials with good performance were optimized. Experimental result shows that Sample C owns the best performance among five cementing materials because of appropriate initial melting temperature, wider melting temperature range and higher thermal expansion coefficient. Meanwhile these performances of cementing materials are very important to the preparation of a good oxidation-resistance ceramic coatings. For the coating with Cr2O3, which was prepared by Sample C and Cr2O3, its high-temperature oxidation-resistance is about 62 times against FeCrAl-matrix at 1200℃ for 30 h in air; while that of the coating with MgO is about 16 times against FeCrAl-matrix accordingly. The properties of cementing materials were characterized, and the relationship between properties and structures of the coatings was investigated by means of thermal state microscope and high-temperature dilatometer, etc.

Preparation of Carbon Aerogels by Conventional Drying and Their Control in Microstructure

QIN Ren-xi;SHEN Jun;WU Guang-ming;ZHOU Bin;WANG Qin;NI Xing-yuan;GUO Yan-zhi

. 2004, 4(5): 429-433.

Asbtract ( )

PDF (350KB) ( )

Related Articles | Metrics

Carbon aerogels were dried successfully at ambient pressure by decreasing catalyst and exchanging solvents. SEM, BET and pore size distribution techniques were used to characterize the morphology and pore structure of the carbon aerogels. The structures of carbon aerogels are controlled from micro pore to macro pore by changing the concentration of catalyst and solvent. The size of the particles increases from less than 100 nm, 100~200 nm to 1~2 mm with R/C ratios increasing from 500, 1000 to 1500. The pore diameter of carbon aerogels decreases from 60 nm, 40 nm to 15 nm by increasing RF concentration from 30%, 40% to 50% while R/C ratio being 1000. The samples prepared by conventional drying have low density of 250~650 kg/m3 and a high specific surface area of 250~550 m2/g. The reaction mechanism of the sol-gel process and the way to dry aerogels at ambient pressure by enhancing material intensity and reducing capillary pressure were discussed.

Preparation of Ba-Ferrite by Co-precipitation Method

LONG Chun-quan;LIU Ying;YU Zhi-yong

. 2004, 4(5): 434-437.

Asbtract ( )

PDF (673KB) ( )

Related Articles | Metrics

For ameliorating the insufficiency of filtrating and washing of traditional techniques in preparation of Ba-ferrite by co-precipitation, fine particles of BaFe12O19 in co-precipitation method have been improved by utilizing the magnetism of Fe3O4, consequently preparation time and cost can be saved, and the necessary temperature for the high-temperature solid reaction lowered. Furthermore, the effect of NaCl flux on particle size, morphology and magnetic performance of fine powder of BaFe12O19 was also studied, and appropriate amount of the flux addition determined.

Cluster Analysis and Visualization Enhanced Genetic Algorithm-I. Eduction, Principle and Analysis

WANG Ke-feng;SUN Xiao-jing;YAO Ping-jing

. 2004, 4(5): 438-444.

Asbtract ( )

PDF (186KB) ( )

Related Articles | Metrics

Genetic Algorithms (GA) based on penalty function methods have been the most popular approach to constrained optimization problems because of their simplicity and ease of implementation. But how to find appropriate penalty parameters needed to guide the search towards the constrained optimum in the penalty function approaches is very difficult. A new cluster analysis based on visualization is proposed to address the constrained optimization problems. First, a Cluster Constrained Mapping (CCM) method based on feed-forward Artificial Neural Network (ANN) is proposed for dimension-reduction mapping from the original n-D space to 2-D, conserving the cluster information in the reduced dimensional space. Then the agglomerative algorithm that works in 2-D space is called upon for cluster analysis. Its parameters are provided through visualization and subsequent interaction with the user. Finally, the cluster information is derived from 2-D back into n-D to obtain the feasible region knowledge in the original dimensions, which is used in the IGA. The enhanced GA, incorporating a new cluster analysis method through data visualization (CCM) and user interaction guarantees the process of evolution in feasible regions without requiring any penalty parameters.

Production of Extremely Thermostable Xylanase in Recombinant Escherichia coli

LOU kai;YU An-feng;XING Xin-hui

. 2004, 4(5): 445-450.

Asbtract ( )

PDF (420KB) ( )

Related Articles | Metrics

Xylanases have shown considerable potential in pulp bleaching, food and feed industries by partial hydrolysis of xylan. Cloning and expression in E. coli of thermostable xylanase gene from the extremely thermophilic anaerobe microbes were studied and the effects of medium composition and high temperature treatment on the production of the extremely thermostable xylanases by recombinant strains were investigated. Plasmids, pET-DBc and pET-TB, carrying the xynB gene from Dictyoglomus thermophilum Rt46B.1 and Thermotoga maritime MSB8, were transformed into Escherichia coli BL21(DE3), respectively, and recombined strains E. coli DB1 and E. coli TB were formed. Xylanase assay and SDS-PAGE analysis indicated that the xylanase gene was expressed. Four kinds of media were used for examination of E. coli DB1 culture in shaken flask. The results indicated that xylanase had a higher specific activity in LB and M9 media than in the other media. Maximal cell density was achieved in TB medium, while the specific activity of xylanase was low. Xylanase produced by E. coli DB1 exihibited high activity at 90°C. The preliminary optimized fermentation medium of E. coli DB1 consisted of (g/L): D-glucose 50, NH4Cl 3, MgSO4 0.5, CaCl2 0.6, Na2HPO4×7H2O 12.8, KH2PO4 3.0, NaCl 0.5. There is little difference between the maximum activity of the extremely thermostable xylanase induced with IPTG and that not induced. The thermostability of the xylanase produced by recombined E. coli DB1 can help to simplify its down-stream process for product recovery and extraction.

Screening of High Productivity CoQ10 Strain and Optimization of Fermentation Conditions for CoQ10 Production with Rhizobium radiobacter

PAN Chun-mei;DU Guo-cheng;CHEN Jian

. 2004, 4(5): 451-456.

Asbtract ( )

PDF (164KB) ( )

Related Articles | Metrics

Rhizobium radiobacte WSH2601 was mutagenized by using UV-radiation and NTG mutation consecutively. An actinomycin-D resistant mutant, R. radiobacte WSH-F06, was isolated after two runs of screening. The CoQ10 yield of mutant WSH-F06 increased by 16% compared to that of the parent strain. The effects of nutritional and environmental conditions on the production of CoQ10 by R. radiobacte WSH-F06 were investigated in shaking flasks. A complex carbon source consisting of glucose (30 g/L) and molasses (60 g/L) was shown to be suitable. In addition, R. radiobacter WSH-F06 could assimilate a variety of nitrogen sources, including organic and inorganic nitrogen compounds. A compound nitrogen source consisting of (NH4)2SO4 (7 g/L), peptone (5 g/L), yeast extract (5 g/L), corn steep liquor (30 g/L) was developed by using orthogonal experiments. The inoculum size had no obvious effect on CoQ10 fermentation. The optimum initial pH for CoQ10 fermentation was 7.2, while the optimum volume of medium (medium volume vs. flask volume ) was 50 mL/500 mL. Under the optimized fermentation conditions, the CoQ10 yield and the intracellular CoQ10 content reached 34 mg/L and 2.4 mg/g, which were 2.6- and 1.1-fold higher than that of the parent strain under the original conditions, respectively.

Effects of Air Flow Rate and CO2 Concentration on the Growth of Nannochloropsis sp. and EPA Accumulation in an Airlift Photobioreactor

XU Fang;HU Han-hua;CONG Wei;CAI Zhao-ling;OUYANG Fan

. 2004, 4(5): 457-461.

Asbtract ( )

PDF (188KB) ( )

Related Articles | Metrics

The effects of air flow rate and concentration of CO2 on the growth of Nannochloropsis sp. cells as well as EPA content in an airlift photobioreactor were investigated. The results show that Nannochloropsis sp. grew faster in the airlift photobioreactor than in the flask. After 8 d culture, the biomass of Nannochloropsis sp. in the airlift photobioreactor reached 857 mg/L, which was 2-fold of that obtained in the flask. The growth rate increased with the increase of air flow rate. Nannochloropsis sp. grew the fastest at the air flow rate of 500 mL/min and no positive effect on the cell growth was observed above this flow rate. 1% (j) CO2 added in the air promoted the growth of Nannochloropsis sp. significantly, thereby the maximal growth rate was 1.8-fold of that without CO2 addition. The highest EPA yield of the culture, 39.0 mg /L, was obtained at the air flow rate of 400 mL/min with 0.5% (j) CO2.

Screening of Bacillus stubilis PGAN-12 and Production ofγ-Polyglutamic Acid by Fermantation

SANG li;XU Hong;LI Hui;ZHANG Lu-jia;JIANG Min

. 2004, 4(5): 462-466.

Asbtract ( )

PDF (246KB) ( )

Related Articles | Metrics

Strain PGAN-12 which could produce γ-polyglutamic acid (γ-PGA) was isolated from soils and identified taxonomically as Bacillus subtilis. PGAN-12 could produce a large amount of γ-PGA in the medium containing glucose and sodium glutamate. The suitable carbon source was glucose, however, when organic acids in TCA cycle including citric acid were used as carbon sources, PGAN-12 did not produce γ-PGA. The optimum nitrogen source was yeast extract. PGAN-12 is a γ-PGA producing strain depending on L-glutamic acid in the medium. In the presence of 70 g/L sodium glutamate, the highest γ-PGA concentration reached up to 18.32 g/L, while 30 g/L sodium glutamate was added, 14.2 g/L γ-PGA was obtained with the highest yield of 62.1%.

The Lubei Eco-industrial Model of China

YANG Li;HU Shan-ying;LIANG Ri-zhong;CHEN Ding-jiang;FANG Xin;LI You-run;SHEN Jing-zhu;FENG Jiu-tian;KONG Ling-quan

. 2004, 4(5): 467-474.

Asbtract ( )

PDF (201KB) ( )

Related Articles | Metrics

Lubei Eco-Industrial System in Shandong province contains three coupled industrial chains. One is the poly-generation of ammonium phosphate，cement and sulfuric acid，the second is the ocean chemical engineering which fully utilizes the sea water resource，the third is the co-generation of salt，alkali and electricity. These three chains construct a new kind of Eco-industrial pattern in which all resources are common used and managed by an unite enterprise. In this paper，by applying principle and methods of industrial ecology ，system engineering and chemical engineering，we finished some quantitative analyses on mass cycle，energy utilization，industrial symbiosis and system flexibility to Lubei eco-industrial system. A systematic Eco-industrial analysis approach and indices are proposed. The result shows that Lubei enterprise group has developed into a mature Eco-industrial system.

Progress in the Production of Adenovirus Vector

QI Li;GU Ming;CONG Wei

. 2004, 4(5): 475-480.

Asbtract ( )

PDF (245KB) ( )

Related Articles | Metrics

Though there are still many challenges to overcome, gene therapy has led to high expectation for curing a broad range of diseases, especially on the treatment of cancer. One of the key problems in clinical application is to construct safe and efficient gene transfer systems. Replication-defective adenoviruses are main vectors of choice, and many kinds of adenovirus vectors have been designed. With the development of research, more adenoviral particles are required. To meet the need of experimental and clinical applications, 293 cell lines which include adherent cell line and suspension cell line are frequently used in production. Methods used in production include batch, fed-batch and perfusion. Quality control of recombinant adenovirus vectors is also very important in the process of production. This review summarizes the production process of adenovirus vectors, mainly concentrated on the adenovirus infection mechanism and methods of production, purification and quantification.

Table of Content