The Correlation between Density and Low-Temperature Creep Property of Asphalt

The density of asphalt was measured with the pycnometer and densitometer. Creep properties of the asphalt were investigated with the bending beam rheometer at temperatures ranging from 0 ℃ to -36 ℃. The asphalt density data used to correlate with the creep properties were calculated from the regression equation of density and temperature. The asphalt sample used to determine the creep property was aged by the standard RTFOT test and the PAV test. The test results showed that the asphalt density had a linear relationship with temperature changes. The logarithm of the creep stiffness and the slope of the logarithm of the stiffness at 60 seconds all demonstrated a linear relationship with the density, and the regression coefficient of these data was around 0.99. The creep stiffness and the slope of the creep stiffness can be calculated from the asphalt density at the same temperature.     

Dearomatization of normal paraffin by adsorption process using synthesized NaX zeolite

Linear alkyl benzenes (LABs) are the main materials for detergent production. The presence of aromatic compounds in this material can decrease the quality of the final product and enhance the deactivation rate of catalysts. In this research we used zeolite NaX for de-aromatization of the recycled paraffin from the alkylation unit of an LAB production complex. The effect of different parameters on the removal efficiency of adsorbent was studied and optimized. To study the re-usability of the adsorbent, the breakthrough curves were obtained by using a fixed bed column filled with the adsorbent. The results indicated that the adsorbent capacity remained unchanged after three regeneration cycles. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. It was concluded that the Langmuir model agreed well with the experimental data. The calculated thermodynamic parameters of the adsorption showed that the adsorption process was spontaneous and exothermic. The reaction rate was estimated by the pseudo-second order kinetic model.     

内插旋流片的缩放管内糖液自然对流的传热研究

The natural convection heat transfer of a 60% sucrose solution in a vertical converging-diverging tube （CD） withregularly-spaced twisted tapes （RSTT） has been investigated numerically and experimentally. The effects of wall temperatureand number of RSTT on the Nusselt number were studied in detail. The distributions of velocity and temperature inthe 60% sucrose solution were studied and the simulated results of CD with RSTT were compared with those of the smoothtube. The influence of Rayleigh number and RSTT on the Nusselt number was conducted experimentally. The results indicatethat the Nusselt number of the 60% sucrose solution obviously increased with the number of RSTT but increased inconspicuouslywith 2 and more twisted tapes. The simulation shows that the distance for achieving an optimal heat transferperformance is 46 times the diameter of the tube. The mechanism of the natural convection heat transfer enhancement of the60% sucrose solution in relationship with the CD and the RSTT was analyzed, and the change of average tangential velocitywith the axial distance was presented to demonstrate that the enhancement of heat transfer was realized mainly because of the increase in tangential velocity.     

DEVELOPMENT OF SUPERIOR RESID DEMETALLIZATION CATALYST AND ITS APPLICATION

The effects of the pore structure of the bimodal catalyst on the residue hydrodemetallization were studied. The simulation of the intra-particle reaction model suggested that an increase in the diffusivity of the macro pore increase the demetallization. The activity tests of several catalyst samples with different pore structure supported the predicted resuits. The new birnodal dematallization catalyst with high demetallization activity as well as large metal uptake capacity was developed, by improving the pore structure and the hydrogenation activity. The pilot runs demonstrated that the new catalyst possesses longer catalytic life as well as higher demetallization activity in the residue desulfurization process.     

The effect of silica nanoparticle aggregates on wax dissolution in diesel oil

In recent years,silica nanoparticle aggregates(SNPAs) have been used to decrease the injection pressure of wells in low permeability reservoirs achieving good results.In order to study the mechanisms for reduction in the injection pressure of low permeability wells by the SNPA-diesel oil system injection,the microstructure of SNPAs was observed with a transmission electron microscope(TEM).The particle size distribution of SNPAs was also measured by the laser scattering method.The viscosities of diesel oil and SNPA-diesel oil system were measured with a capillary viscometer.The effect of SNPAs on the solubility of wax in the diesel oil was experimentally studied.The influencing factors,including temperature and SNPA concentration in diesel oil,on wax solubility were analyzed.A pore-throat film displacement model(PTFDM) was built for mechanism explanation.The microstructure and size distribution analyses show that the SNPAs are in the nanometer size range.The viscosity of the SNPA-diesel oil system is lower than that of the diesel oil.The solubility of wax in the diesel oil increases greatly due to SNPA addition,the solubility ratio reaches 7.5.The solubility of wax in diesel oil increases with increases in the concentration of SNPAs in the diesel oil and with the temperature.It is proved that the addition of SNPAs to diesel oil helps remove the wax deposited near the wellbore.This maybe one of the main mechanisms for injection pressure decreases in low permeability reservoirs.     

Features of the fault system and its relationship with migration and accumulation of hydrocarbon in Liaodong Bay

The fault system of Liaodong Bay developed extensively under the control of the Tanlu Fault.The fault system can be grouped into strike-slip faults of grade I,trunk faults of grade II and branch faults (induced faults) of grade III respectively based on its developmental scale.The faults of grade I and II were deep,early and large while the faults of grade III were shallow,late and small.The formation,evolution and distribution features played a significant role in controlling the migration of oil and gas in both horizontal and vertical directions.The fluid transfer in the fault system occurred in the process of faulting.The strike-slip and trunk faults moved actively forming predominant pathways for oil and gas migration.The branch faults,with weak activity,generally controlled the development of traps and were beneficial for the accumulation and preservation of oil and gas.The faults of grade I and II formed the major migration pathways for oil and gas,but their fault activity rates appeared to vary along their strikes.The zones with a relatively low fault activity rate might be favorable for oil and gas accumulation.When the activities of strike-slip,trunk,and branch faults came to a halt,the fault seal behavior had a vitally important effect on the accumulation of oil and gas.The controlling role of the fault over fluid distribution was further analyzed by calculating the fault activity quantitatively.     

超重力技术制备甲醇柴油乳化燃料分散性能研究

A new continuous process for preparing methanol-diesel emulsified fuel with an Impinging Stream-Rotating Packed Bed is proposed. The droplet size of dispersed phase(methanol) of the emulsified fuel has a significant effect on the combustion of methanol-diesel emulsified fuel. In this paper, the methanol-diesel emulsified fuel uses diesel as the continuous phase and methanol as the dispersed phase. The Sauter mean diameter of the dispersed phase of methanol-diesel emulsified fuel was characterized with microphotography and arithmetic method. The experimental result showed that the Sauter mean diameter of the dispersed phase, which was decreased with the augmentation of the high gravity factor, liquid flow rate and emulsifier dosage, was inversely proportional to the methanol content. The Sauter mean diameter of the dispersed phase can be controlled and adjusted in the range of 12—40 μm through the change of operating conditions. The correlative expressions of the Sauter mean diameter of emulsified fuel were obtained and the calculated values agreed well with the experimental values.     

New Method of Predicting the Thermodynamic Properties of Solutions

Thermodynamic functions solutions of a 25 binary systems formed n-alcohols and esters of aliphatic acids by were calculated using the standards ideal solution and ideal gas. The value change regularity of the thermodynamic functions of solutions depending on their molar mass and concentration of the solutions＇ components was determined by the thermodynamic analysis. The method of prediction of the thermodynamic properties of binary solutions was suggested on the basis of the determined regularities. The corresponding equations were obtained.     

埃洛石纳米管负载氮掺杂二氧化钛的制备及其太阳光光催化性能

The N-doped TiO2-loaded halloysite nanotubes(N-Ti O2/HNTs) nanocomposites were prepared by using chemical vapor deposition method which was realized in autoclave. The photocatalytic activity of nanocomposites was evaluated by virtue of the decomposition of formaldehyde gas under solar-light irradiation. The XRD patterns verified that the anatase structured TiO2 was deposited on HNTs. The TEM images showed that the surface of HNTs was covered with nanosized TiO2 with a particle size of ca. 20 nm. The UV-vis spectra indicated that the N-Ti O2/HNTs presented a significant absorption band in the visible region between 400 nm and 600 nm. Under solar-light irradiation, the highest degradation rate of formaldehyde gas attained 90% after 100 min of solar-light irradiation. The combination of the photocatalytic property of TiO2 and the unique structure of halloysite would assert a promising perspective in degradation of organic pollutants.     

Inherent relations between yield stress and stability of bubble petroleum coke water slurry

The stability of petroleum coke water slurry(PCWS) is currently a hot topic. The inherent relationship between yield stress and stability of bubble-PCWS was studied through orthogonal experiments and range analysis in this work. The results showed that the stability of bubble-PCWS was positively related to the yield stress and that the yield stress could be greatly impacted by the operation conditions during preparation of bubble-PCWS. The main factors affecting the yield stress of bubble-PCWS were solid concentration, aeration time and dosage of frother. However, the effects of aperture size of air distribution plates and type of frother on the yield stress were slight within the experimental range. The optimal conditions for the greatest yield stress were as follows: aeration time of 30 min, solid concentration of 65 wt%, frother dosage of0.030 wt% of the air-dried pulverized petroleum coke, aperture size of air distribution plate of 2–5 lm and AOS frother.The yield stress and the pour rate of bubble-PCWS under this optimum operation condition could reach maxima of more than 0.4 Pa and 96%, respectively.     

Study on Removing Trace Olefins in Aromatic Hydrocarbons with HPMo-loaded Y Zeolites

HPMo-loaded Y-zeolites were prepared for the removal of trace olefins from aromatic hydrocarbons. The temperature of calcination and the proportion of phospho-molybdic acid in the catalyst were studied. The catalytic activity for olefins removal and the service life of the catalyst were tested in a fixed bed microreactor. The results showed that the catalyst containing 3% phospho-molybdic acid, which was calcined at 550℃, demonstrated the best activity for olefins removal. The catalyst could be regenerated and could perform still very well. Catalyst characterization was performed by XRD and measured by pyridine-FTIR spectrometry. The test results indicated that the activity of the catalyst was related with the effect of acid concentration and acid strength. Besides, the deactivation of the catalyst was associated with the formation of coke deposits and the deactivated catalyst could recover its activity by oxidation with air under a proper temperature.     

正己烷在FAU和MFI型沸石分子筛催化剂上的转化途径

 Based on the reaction pathways of n-hexane over catalysts and the molar selectivity of products, the independent reaction equations of n-hexane over zeolite catalysts are established. The correlation of independent reaction equations with molar selectivity of products is set up, and the molar selectivity of the independent reactions is calculated. The results show that the position of α cracking of C6 carbonium ion is favorable to the middle of carbon chain. The proportion of mono-molecular reactions over catalysts of MFI, MFI+FAU and FAU type are 75.87%,32.01% and 31.46%, respectively. The large products such as propane and propene are generated from both mono-molecular reaction mechanism and bi-molecular mechanism. The ratio of mono-molecular to bi-molecular reaction mechanism of n-hexane over zeolite catalysts is related to zeolite type. The molar selectivity of independent reactions is valid which is proved by n-hexane and H+.     

A pH Model for Calculating the pH Value of Mixed–Acid–Base Equilibria of Overhead Condensing Systems in Crude Distillation

A pH predictive model based on acid–base equilibria and ion equilibria was proposed to calculate the pH value of the overhead condensing system of crude distillation unit. The pH model could be used to predict the appropriate amounts of neutralizers by measuring the Cl-ion concentration of the overhead knockout drum. The pH values of various neutralized streams were estimated by this model. The results showed that the predicted pH values were in good agreement with the experimental ones. The trend of the corrosion inhibition efficiency decreases in the following order: ethylenediamine N,Ndimethylethanolamine triethylamine 3-methoxypropylamine morpholine. The difficulty in the accurate control of corrosion was solved, and a good instruction was provided for mitigating corrosion in refinery.     

Stress analysis on large-diameter buried gas pipelines under catastrophic landslides

This paper presents a method for analysis of stress and strain of gas pipelines under the effect of horizontal catastrophic landslides. A soil spring model was used to analyze the nonlinear characteristics concerning the mutual effects between the pipeline and the soil. The Ramberg–Osgood model was used to describe the constitutive relations of pipeline materials. This paper also constructed a finite element analysis model using ABAQUS finite element software and studied the distribution of the maximum stress and strain of the pipeline and the axial stress and strain along the pipeline by referencing some typical accident cases. The calculation results indicated that the maximum stress and strain increased gradually with the displacement of landslide.The limit values of pipeline axial stress strain appeared at the junction of the landslide area and non-landslide area. The stress failure criterion was relatively more conservative than the strain failure criterion. The research results of this paper may be used as a technical reference concerning the design and safety management of large-diameter gas pipelines under the effects of catastrophic landslides.     

Effects of Different Heavy Crude Oil Fractions on the Stability of Oil-in-water Emulsions — the film properties of heavy crude functional components and water system

A series of π-A isotherms are drawn to study the film properties of the components with Langmuir-Blodgett technique. The effects of the aromaticity of spread solvents and pH value on the air/water film formed by the components are investigated. Acid fraction and asphaltene can form stable two-dimensional insoluble films on an air/water surface.The surface film pressure of acid fraction and asphaltene is higher and more stable than that of the other fractions. The surface film pressure of the fraction increases evidently under the basic condition (pH=12). The results show that the interfaciai activity of acid fraction and asphaltene is superior to that of the other fractions and the basic condition is favorable to the stability of the O/W emulsion.     

钨酸锆催化剂的成型以及黏结剂在异构化中的作用

The present work reports the new results of pseudo-boehmite addition as binder in the synthesis of the shaped Pt/WO3-ZrO2-Al2O3 (denoted as PtWZA) catalysts. The results showed that the shaping with binder can noticeably influence the structure, acidity of catalyst and then improved the catalytic performance in n-heptane isomerization, except for providing the mechanical strength of the catalyst. The suitable binder content could improve the isomerization activity and/or selectivity by changing the acidity of PtWZA. The influence of binder content depended on WO3 content in the catalyst. The PtWZA catalysts containing 5-15wt% binder (dry basis content of binder) possessed favorable isomerization performance, depending on the contents of WO3. The suitable catalyst contained Pt20WZ5A and Pt30WZ15A, which could give approximately 80-90% conversion and 90% selectivity. These new findings enriched the knowledge of the binder in the catalyst shaping process that will be useful in the production of industrial catalysts.     

Chemical Composition and Mechanical Characteristic of Nitrogen Ion Beam Mixed Carbon Nanolayer

Ion beam methods for modification of nanohardness of surface nanolayers of the titanium alloy Ti6AI4V were applied. After deposition of carbon nanolayers by electron beam evaporation, the ion implantation of nitrogen into samples was carried out. The chemical composition of the modified surface area was investigated by AES （auger electron spectroscopy）. The nanohardness of resulted ion beam modified surface nanolayers were investigated by nanoindentation testing. The measured concentration profiles indicate the atomic mixing of carbon into the substrate. It was found that the modified samples had a markedly higher nanohardness than the unmodified samples. The increased nanohardness is attributed to the newly created phases in the surface area.     

The Effect of Non-Framework Aluminum on the Stability and Activity of REY Zeolite

The present study is focused on the influence of a routine step, washing, following the preparation of calcined rare earth exchanged Y zeolite, on its hydrothermal stability. The hydrothermal stability of REY products, which were washed by different reagents, was observed and characterized by XRD, ICP, NMR, etc. The results reveal that the amount and the chemical type of the acidic media used for washing can significantly influence the content of remaining non-framework aluminum （NFA） and consequently further affect the hydrothermal stability of the washed REY products. The content of remaining non-framework aluminum can be well correlated with the crystallinity of REY products.     

Study on Salt-Containing Extractive Distillation for the 2-Propanol/Water System

The salt-containing extractive distillation column and the salt-containing agent recovery column for the 2-propanol/water/ethanediol/KAc system were simulated by the NRTL model and the modified Rose Relaxation method. The simulation results showed that prediction of the salt effect in vapor-liquid equilibrium and the correlation method （TDCM） of NRTL parameters were suitable for the said system. Four different distillation technology processes were investigated; the results showed that the salt-containing extractive distillation process was the best one. The simulating design of the extractive distillation column was performed under the conditions of different total stage number, feeding location, reflux ratio, amount of mixed agent and concentration of KAc. The results showed that such factors as 17 stages, a feeding location at the 9th stage, a reflux ratio of 1.2, and a mixed agent feeding rate of 1.141 kmol/h, might be the best suited operating conditions. The simulating design was also done for the column for recovering the salt-containing agent. The simulation method of the salt-containing extractive distillation is simple and effective in this work.