缸内直喷汽油机起动控制

在缸内直喷增压汽油机上,运用自主开发的直喷发动机控制软硬件系统,研究了喷油脉宽、点火提前角和起动过程PID控制器参数对发动机起动的影响。试验结果表明：喷油脉宽为45℃A,发动机起动转速波动小。点火提前角为12℃A时,发动机起动转矩最大。PID控制的KP=1时,转速响应迅速;KI=0.2时,实现无误差跟踪转速,超调量小;...     

芳构化催化剂研究进展

总结了当前国内外轻烃芳构化的研究进展，对目前正在研制开发的芳构化催化剂做了较详细的阐述。针对芳构化工艺中催化剂的不足之处，介绍了目前改善芳构化催化剂催化性能的前沿技术，并对催化剂的活性中心、反应机理的研究进行了系统的概述。     

Combined effects of pressure and ion-exchangeable metallic species on pyrolysis of Victorian lignite

A set of ion-exchanged samples prepared from Loy Yang lignite was pyrolyzed in a wire-mesh reactor at elevated pressures from 1 to 36 bar. The tar yields from the pyrolysis of H-form (acid-washed) sample at a fast heating rate of 1000 °C s⁻¹ were drastically reduced by increasing pressure to 6 bar and then remained unchanged with further increase in pressure to 36 bar. This behavior of the tar yield was in sharp contrast to that from the raw lignite which showed a minimum with increasing pressure. The sensitivities of the tar yields to changes in the heating rate were also suppressed by increasing pressure. The tar yields from Ca-form and Na-form samples (prepared by ion-exchanging Ca and Na on the H-form sample, respectively) were not very sensitive to changes in the heating rate and pressure up to 11 bar. At 20 bar, the tar yields from the Na-from sample nearly doubled whereas from the Ca-form sample nearly halved compared to those respective values at 1 bar. Although increasing pressure is thought to cause changes in the intra-particle mass transfer processes of volatile precursors, the rate of formation of volatile precursors tends to dictate the kind of mass transfer process responsible for the release of volatiles. Therefore, depending on the pyrolysis condition, bulk diffusion or forced flow would dominate the mass transfer processes for the release of volatiles. The introduction of cations is thought to result in irreversible changes in the lignite structure and not only control the process of formation but also the amount of volatile precursors and in turn alter the effects of pressure. Valence and catalytic activity of cations seem to play important roles in determining pyrolysis products distribution at elevated pressures.     

荆门石化生产国家新标准汽油技术进展

我国车用汽油标准再度升级,将车用汽油硫含量标准由0.08%降至0.05%,2005年7月1日已经在全国范围内强制执行.荆门石化的目标是以较小成本生产出符合国家新标准的清洁汽油,为此在原料优化选择、工艺路线、装置改造,工艺流程等方面进行了优化,并实施了一系列降硫技术措施,2005年7月1日之前,已生产出5万t符合国家新标准的清洁汽油,取得了历史性的新进展.     

SIMULATION OF LIGNIN PYROLYSIS

Model compound pyrolysis reaction pathways and kinetics were used in simulation of both native (e.g.. milled wood) and Kraft lignin thermolyses where either only primary or also secondary reactions are important.

Predicted products fell into one of permanent gases, tight liquids, phenolics and carbonaceous residue fractions. Product yields were more dependent on lignin type than on reaction environment.

Comparison of simulation predictions with experimental pyrolyses of actual lignins, accomplished in terms of both product identities and yields, is encouraging. It is noteworthy that the simulations are strictly a priori and incorporate no actual lignin pyrolysis information.     

清洁汽油炼油工业所面临的挑战与对策

分析了我国现行的汽油标准及生产状况,并与国际水平的车用汽油标准进行了比较,总结出我国炼油企业生产清洁汽油所面临的挑战,提出了生产清洁汽油的技术对策。     

Combustion behavior of xylite/lignite mixtures

The behavior and the kinetics in nitrogen and air of two low-rank coals (lignite and xylite) and their blends, as well as the compatibility of the component coals in the blends were evaluated, in an effort for the rational use of poor coals.The experiments were conducted in a thermobalance system, at non-isothermal heating conditions, with heating rates of 20 and 100 °C/min, in the temperature range of 25-850 °C. Material particle size was −100 μm.A first-order parallel independent reactions model and a power law model fitted successfully the rate data of pyrolysis and combustion, respectively. Activation energy values and reaction orders ranged from 23 to 182 kJ/mol and 0.8 to 2 respectively. The heating rate did not affect the kinetic parameters considerably, however when this was increased the reactions were shifted to higher temperatures and the rates were greater.The pyrolysis kinetics of lignite/xylite blends could be sufficiently predicted, based on the data of the individual fuels. However, this was not true in the case of char combustion. Blending of lignite with xylite, in any proportion, seemed to cause some interactions between the component coals in air.     

Analysis of gas phase compounds in chemical vapor deposition of carbon from light hydrocarbons

Product distributions in the pyrolysis of ethylene, acetylene, and propylene are studied to obtain an experimental database for a detailed kinetic modeling of gas phase reactions in chemical vapor deposition of carbon from these light hydrocarbons. Experiments were performed with a vertical flow reactor at 900 °C and pressures from 2 to 15 kPa. Gas phase components were analyzed by both on-line and off-line gas chromatography. More than 40 compounds from hydrogen to coronene were identified and quantitatively determined as a function of the residence time varied up to 1.6 s. Product recoveries were generally more than 90%. Analysis of the kinetics of the conversion of the hydrocarbons resulted in global reaction orders of 1.2 (ethylene), 2.7 (acetylene), and 1.5 (propylene). First order dehydrogenation reactions and third order trimerization reactions leading to benzene are decisive reactions for ethylene and acetylene, respectively. Conversion of propylene should also be based on two simultaneous reactions, a first order dissociation reaction, and second order reactions such as bimolecular reaction of propylene resulting an allyl and a propyl radical. These insights should be useful to develop a reaction mechanism based on elementary reactions in forthcoming studies.     

CO+H_2两段法(MFT)合成汽油过程开发(Ⅱ)中间工厂试验

本文介绍了两段法100t油/年规模的合成油中间试验工艺流程与试验结果。重点考察了工业水煤气的净化效果,催化剂经放大制备后的活性及稳定性,测试了一、二段反应器床层温度分布,解决了一段强放热反应的稳定性操作,经1600小时运行,找到了装置的较佳操作条件,在该条件下,油收可达90～100g/Nm~3(CO+H_2),油品辛烷值(马达法)≥80。为工业放大提供了工程数据。     

汽油加氢反应动力学的适时校正和反应器的模拟

分析了汽油加氢过程的主要反应，对复杂系统的反应动力学进行集总简化，建立了加氢反应器的数学模型，并采用适时校正的方法对汽油加氢反应器操作特性进行模拟计算，讨论了一些操作参数对加氢效率的影响，并对加氢操作进行了分析。