车用柴油机微粒排放控制技术的近况分析

0 前言 柴油机排气中的微粒可分为不可溶有机物和有机可溶物(简称SOF)。不可溶有机物的主要成份是干碳粒,还含有硫酸盐。干碳粒可占到微粒排放总量的50％以上,是微粒的主要成分。有机可溶物由没有燃烧的柴油和润滑油分子构成,因其可溶于有机溶剂故而得名。 柴油机排气微粒的粒径大都在1μm以下。这样小的微粒吸入人的肺部会在肺部积     

柴油机排气微粒中可溶有机成分及苯并（a）芘的实验测定

本文用溶剂萃取法和热重法测量了柴油机排气微粒中可溶有机成分,研究了它随发动机负荷的变化关系,并比较了溶剂萃取与热重法所得的结果。本文还对微粒中的苯并(α)芘进行了定量分析并给出了结果。     

WD615.67型柴油机常态排气微粒成分试验测定及分析

设计制作了适合柴油机常态排温下使用的微粒采样装置,试验测定了ＷＤ６１５．６７型柴油机５种常态工况下排气微粒中不可溶组分（ＩＯＦ）和可溶组分（ＳＯＦ）的百分 含量,并利用色谱－质谱联用装置对ＳＯＦ进行了化学组成成分分析,试验结果表明：微粒ＳＯＦ中的烃类大部分为直链烷烃,此外还有少量支链烷烃;相同转速下,随负荷的增加,排气微粒中ＳＯＦ百分含量减少,ＩＯＦ百分含量增加;相同负荷下,随转速的增加,微粒中Ｓ     

车用直喷柴油机递增负荷工况下的微粒排放特性

采用自行设计的柴油机微粒袋式取样系统对车用柴油机恒转速、增转矩工况下的微粒排放进行了研究。试验结果表明:在恒转速增转矩瞬态工况下,随着转矩增加率的增大,微粒及其不可溶成分和可溶性有机成分排放量均增加;高转速时转矩增加率对微粒排放的影响稍大。不可溶成分的增加是微粒排放量增大的主要原因,但转速较低时可溶性有机成分的增加也不容忽视。冷却介质温度较低时微粒排放量增大。     

车用直喷柴油机排气微粒的排放规律

在直喷式车用柴油机的各种稳态工况下测量了排气微粒、微粒的不可溶组份和微粒的可溶组份的排放规律。试验结果表明，微粒的可溶组份主要产生于中、小负荷。微粒的不可溶组份峰值在大负荷，随空燃比减小而增加。     

柴油机微粒排放的净化技术

1前言柴油机的微粒排放不同程度地危害人类和破坏其生态环境，所以净化柴油机的微粒排放问题受到人们的日益关注．本文介绍世界各国开发的柴油机微粒排放的净化技术，并分析各种技术的特点和存在问题．2柴油机微粒排放柴油机排放物中的有害成分主要有CO、IIC、NO：、微粒等，而微粒的成分主要包括碳烟颗粒（占30y）、可溶碳氢有机物（占35y）、硫及水（占35％）．由于排放的微粒比表面积大、吸附力强（吸附有多环芳香烃、苯并葩等）且微粒直径小（只有0．of－0．05pm）、重量轻，故能长时间悬浮在大气中，易被人体吸人并沉积在肺胞中，对…     

车用直喷柴油机加速工况下进气、供油及微粒排放的动态响应

采用自行设计的瞬态工况控制及测量系统，研究车用柴油机恒转矩递增转速工况下进气、供油及微粒排放的动态响应，结果表明，对于恒转矩递增转速瞬态工况过程，存在进气响应滞后和燃油流量超调的现象，随着转速增加率的提高，微粒及其可溶性有机成分和不可溶成分的排放量均增加。     

利用燃烧室内直接采样研究直喷式柴油机微粒的形成

本文叙述了直喷式柴油机微粒（ＰＭ）的形成。并利用一种电磁驱动的采样阀系统在燃烧室内直接进行燃气采样。 对应于不同的曲轴转角和燃烧室内不同位置,分别测量了总微粒及两种组分,可溶性有机成分和不可溶性有机成分的浓度。测量发现,沿着油束喷射轴线方向采样位置上ＳＯＦ的浓度较高,靠近燃烧室壁面附近的采样位置上ＳＯＦ和ＩＳＦ的浓度比远离壁面位置的高。 实验结果显示,ＳＯＦ的形成明显受到油束壁面激冷的影响,燃烧室中微粒的浓度也比排气中的高得多。     

柴油机排气微粒中SOF成分的试验研究

在柴油机排气管状态下，采用自行设计的微粒采样装置对十三工况下的排气微粒进行了采样，利用气相色谱一质谱联用技术对微粒中可溶性有机组分(SOF)的成分进行了测定、分析；还测定了排气温度对微粒排放质量流量及SOF组分的影响。结果表明：在排气管采样状态下，微粒SOF组分中80％左右为正烷烃和支链烷烃，碳数从C9～C26，余下组分为多环芳香烃(茚、芴、菲、萘等的同系物)以及少量其它有机物；同一工况下，随采样温度升高，微粒排放质量流量、SOF组分种类均呈现减少的趋势。     

生物短期试验(Ames试验法)用于柴油机排气微粒直接致突变性的研究

运用生物长期试验（Ames试验）探讨了柴油机排气微粒的直接致突变性。并对发动机不同工况下微粒的直接致突变性变化进行了评估,所用的菌种为TA98和TA100,主要考察碱基对置换突变和移码致突变,试验结果表明,柴油机排气微粒Ames试验显阳性,具有强烈的致突变性。菌落回变数同柴油机微粒质量及排气体积线性关系不明显;除了多环芳烃外,还有其它有机物质对柴油机直接致突变性影响很大;大气微粒的单位质量致突变性同柴油机相当,而单元体积的致突变性,柴油机要比大气高近万倍。     

三种不同中国煤中多环芳烃的分布特征研究

对 3种不同原煤用二氯甲烷作萃取剂经索氏提取和K -D浓缩 ,采用硅胶柱层析纯化 ,利用高效液相色谱法 (HPLC)分别对上述提取液中的 16种多环芳烃 (PAHs)进行了定性、定量测定 ,研究了不同煤种多环芳烃的分布。结果表明 ,3种原煤中的PAHs以三环、四环和五环PAHs为主 ,并且煤级越高 ,PAHs的总量越少 ;另外 ,原煤中多环芳烃的含量与各煤质参数之间存在着一定的关系     

Effect of n-hexane extraction on the formation of light aromatics from coal pyrolysis and catalytic upgrading

In order to investigate the effect of aliphatics in coal on the formation of light aromatics (benzene, toluene, ethylbenzene, xylene and naphthalene, called BTEXN) from coal pyrolysis and catalytic upgrading using on-line Py-GC/MS, n-hexane was used to extract Shengli lignite (SL) and Pingshuo bituminous coal (PS). The extracts of the two coals (SLE and PSE) were analyzed by GC × GC-MS. Results show that aliphatics account for 85% of SLE and 68% of PSE. It brings about that the total yields of BTEXN from SL residue and PS residue pyrolysis are decreased by 29% and 18% compared with raw coals. This is because the aliphatics could provide small-molecule free radicals to stabilize the light aromatic cracking fragments and promote the formation of BTEXN during pyrolysis. The amounts of the alkyl benzene series, phenols, and polycyclic aromatic hydrocarbons from pyrolysis gaseous tar are significantly increased after extraction and they will undergo catalytic cracking to form BTEXN over USY zeolite, resulting in that the total yield of BTEXN from residue is almost same as that from raw coal during catalytic upgrading.     

Hydrophobic organic compounds from hydrothermal liquefaction of bacterial biomass

The residual biomass of Cupriavidus necator, a biopolyester-producing bacterium, was liquefied in subcritical water at 300 °C. The hydrophobic organic compounds, accounting for about 45% carbon of the original biomass, were recovered with methylene dichloride for analysis. The organic compounds included hydrocarbons such as long chain alkane and benzene, and nitrogen-containing heterocycles such as pyrroles and indoles. The liquid had the similar elemental composition (C, H, O, N) and high heating value (34 MJ kg⁻¹ HHV) of the bio-oils derived from microalgae biomass.     

Performance improvements of alkaline batteries by studying the effects of different kinds of surfactant and different derivatives of benzene on the electrochemical properties of electrolytic zinc

Electrolytic zinc powders were prepared in 12 M KOH, 4 wt.% zinc oxide solutions in the presence of different kinds of surfactant and organic additives using the galvanostatic technique. Then the electrochemical behavior of zinc was investigated using the sweep voltametry technique. Zinc samples electrolyzed in the presence of cationic cetyl trimethyl ammonium bromide (Zn-CTAB), have maximum corrosion rate. Furthermore, scanning electron microscopy revealed the highest surface area. Zinc deposited with anionic surfactants, sodium dodecyl benzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS), have high dendritic and secondary growth. More zinc ions electrolyzed on the cathode electrode in the presence of SDBS compared with SDS. We suppose the Benzene molecule in SDBS changes morphology, thus effects of the benzene molecule is investigated by utilizing several organic compounds during zinc electrodeposition. Naphthalene with 10 pi electrons at two fused rings decreases corrosion rate and needle growth of zinc deposited, compared to benzyl chloride which has 6 pi electrons. Enhanced delocalization of pi electrons by strongly activating group (–NH₂) in the aniline molecule increases the corrosion rate and dendrites compared with benzyl chloride, which has the weakly activating group (–CH₂Cl). The addition of chloro benzene with inactivating and electrodrawing group (–Cl) creates high surface area without any dendritic growth. The effects of electrolyte additives on the electrochemical capacity of AA-sized alkaline Zn-MnO₂ batteries are verified. The addition of Triton X-100 in anode gel resulted in maximum electrical capacity. Anionic (SDBS and SDS) additives gave higher electrical capacity than cationic (CTAB). Also, the reaction mechanism for zinc electrodeposition in alkaline electrolytes and its dependence upon the presence of organic additives are discussed in detail.     

Anion conductive poly(tetraphenyl phthalazine ether sulfone) containing tetra quaternary ammonium hydroxide for alkaline fuel cell application

The poly(tetraphenyl ether ketone sulfone)s (PTPEKSs) were synthesized from 1,2-bis(4-fluorobenzoyl)-3,4,5,6-tetraphenyl benzene (BFBTPB) and bis(4-fluorophenyl) sulfone with bis(4-hydroxydiphenyl) sulfone in sulfolane. The synthesis of poly(tetraphenyl phthalazine ether sulfone)s (PTPPESs) was carried out via an intramolecular ring-closure reaction of dibenzoylbenzene moiety with hydrazine monohydrate. The PTPPES-QAHs [poly(tetraphenyl phthalazine ether sulfone-quaternary ammonium hydroxide)]s were synthesized via chloromethylation of PTPPES, quaternization with trimethylamine, and followed by an anion exchange of tetra-quaternary ammonium chloride polymers with KOH. Different contents of quaternized unit in PTPPES-QAH (15, 20, 25 mol% of BFBTPB) were studied by FT-IR, ¹H NMR spectroscopy, and thermogravimetric analysis (TGA). Sorption experiments were conducted to observe the interaction of quaternized polymers with water. The ion exchange capacity (IEC), ion conductivity and cell performance of PTPPES-QAH were evaluated with increasing the degree of quaternization.     

炼厂催化裂化干气中稀乙烯资源利用综述

利用催化裂化于气中廉价的乙烯资源生产化工产品可增加炼厂经济效益。介绍了炼厂催化裂化干气稀乙烯的回收技术．包括变压吸附、配合吸收分离、中冷油吸收、先进回收系统、膜分离技术,并对这几种技术进行了比较。最后综述了我国以催化裂化干气为原料生产乙苯、丙醛、乙酸乙酯和氯乙烯的技术研发进展。     

催化器对汽油机苯排放的影响

无铅汽油的广泛使用,使得汽油机苯及苯系物等有害物质的排放量有所增加.为了解三元催化器对汽油燃烧过程中苯及苯系物生成的影响,在HL495IQ电喷汽油机上进行了一系列试验.通过活性炭采样管收集尾气中的排放物,经气相色谱仪分析得到苯及苯系物的排放量,并对其生成规律进行了分析.     

Evolution of soot size distribution in premixed ethylene/air and ethylene/benzene/air flames: Experimental and modeling study

The effect of benzene concentration in the initial fuel on the evolution of soot size distribution in ethylene/air and ethylene/benzene/air flat flames was characterized by experimental measurements and model predictions of size and number concentration within the flames. Experimentally, a scanning mobility particle sizer was used to allow spatially resolved and online measurements of particle concentration and sizes in the nanometer-size range. The model couples a detailed kinetic scheme with a discrete-sectional approach to follow the transition from gas-phase to nascent particles and their coagulation to larger soot particles. The evolution of soot size distribution (experimental and modeled) in pure ethylene and ethylene flames doped with benzene showed a typical nucleation-sized (since particles do not actually nucleate in the classical sense particle inception is often used in place of nucleation) mode close to the burner surface, and a bimodal behavior at greater height above burner (HAB). However, major features were distinguished between the data sets. The growth of nucleation and agglomeration-sized particles was faster for ethylene/benzene/air flames, evidenced by the earlier presence of bimodality in these flames. The most significant changes in size distribution were attributed to an increase in benzene concentration in the initial fuel. However, these changes were more evident for high temperature flames. In agreement with the experimental data, the model also predicted the decrease of nucleation-sized particles in the postflame region for ethylene flames doped with benzene. This behavior was associated with the decrease of soot precursors after the main oxidation zone of the flames.     

Chemical and morphological characterization of soot and soot precursors generated in an inverse diffusion flame with aromatic and aliphatic fuels

Knowledge of the chemical and physical structure of young soot and its precursors is very useful in understanding the paths leading to soot particle inception. This paper presents chemical and morphological characterization of the products generated in ethylene and benzene inverse diffusion flames (IDF) using different analytical techniques. The trend in the data indicates that the soot precursor material and soot particles generated in the benzene IDF have a higher degree of complexity than the samples obtained in the ethylene IDF, which is reflected by an increase in the aromaticity of the chloroform extracts observed by ¹H NMR and FT-IR, and shape and size of soot particles obtained by TEM and HR-TEM. It is important to highlight that the soot precursor material obtained at the lower positions in the ethylene IDF has a significant contribution of aliphatic groups, which play an important role in the particle inception and mass growth processes during the early stages of soot formation. However, these groups progressively disappear in the samples taken at higher positions in the flame, due to thermal decomposition processes.     

无铅汽油在定容燃烧过程中苯排放的试验研究

无铅汽油的广泛使用,使得汽车排放物中有害物质苯的数量有所增加。为了解汽油燃烧过程中苯的生成规律,选用93#汽油、基础油和适当比例的添加剂为试验燃料,在定容燃烧弹上进行了一系列试验研究,利用气相色谱仪分析得到苯的排放量。试验结果表明,燃烧产物中的苯源于未完全燃烧的燃油,燃烧过程中裂解出的小分子自由基也会形成苯,在燃料中添加乙醇后,苯的排放量并不一定增加。