城市垃圾热解产物的GC-MS分析

在温度为900℃下,采用热裂解仪,并结合气相色谱质谱联用技术,对城市垃圾热解产物的主要热解成分和分子量进行定性分析;为了保证实验数据的精确性,主要选用了热解产物的相似度在90%以上的物质。结果表明,城市垃圾在900℃温度下热解的产物主要有烷烃类、烯烃类、酸类、酯类和酚、呋喃类以及其他,其中垃圾中的厨余成分含有的热解产物有16种,废纸屑中含有19种,木废料中含有16种,塑料中含有26种,纤维织物中含有27种。通过对城市垃圾热解产物的GC-MS分析,了解城市垃圾的热解机理,并为城市垃圾的能源化利用提供依据。     

污泥-花生壳共热解气相产物研究

采用外热式反应釜,以CH_3COOK为催化剂进行污泥-花生壳共热解气相产物的研究。考察花生壳添加量、热解温度、催化剂添加量、热解时间对共热解气相产物的产率、组成和热值的影响。研究结果表明:随着花生壳添加量的增加,气相产物的产率和热值均先增大后减小,花生壳添加量为80%时,气体热值达到最大,CH_4体积百分数达到10.57%;随着热解温度的升高,气相产物的产率和热值均先增大后减小,H_2体积百分数呈增大趋势,热解温度为600℃时,气体热值达到最大,CH_4体积百分数达到21.86%;随着催化剂添加量的增加,气相产物的产率和热值均先增大后减小,催化剂添加量为6%时气体热值达到最大;随着热解时间的延长,气相产率迅速增大后趋于平缓,气体热值缓慢增大后减小,热解时间为150 min时,气体热值达到最大值27.92MJ/m3,CH_4体积百分数达到28.33%。     

黄连木籽油热解产物气相色谱-质谱分析及物性测定

应用热解法进行黄连木籽油热解实验。对热解产物做气相色谱-质谱分析,结果表明,黄连木籽油热解产物的成分大部分为烷烃和烯烃,碳链长度为11～18。通过分析热解产物与黄连木籽油的关系,发现甘油三酸酯在热解过程中,酯基的α和β碳原子之间的价键发生断裂。测定热解产物的物性,与柴油相比较得出,黄连木籽油热解产物的低热值稍低于柴油,运动粘度与柴油相当,闪点低于柴油很多。基于Vogel方程导出了热解产物的粘温关系式。     

生物质热解生物油的成分分析

在流化床上快速热解玉米秸秆粉,得到成分复杂的生物油.生物油上层是溶于水的轻质液体,下层是难溶于水的大分子物质.用二氯甲烷萃取上层液体中的有机相,气质分析(GC/MS)结果表明其主要成分除乙酸、羟基丙酮外,还有环戊烯酮、糠醛、糠酮、苯酚等及其衍生物,与谱库中的标准物对比有较高的匹配度.下层大分子部分化学性质更为复杂,需要进一步探究分离和检测方法.由于理化性质复杂,生物油的应用需要进一步的研究探讨.     

家蝇蛆油脂的GC-MS分析及合成生物柴油的研究

家蝇蛆系完全变态昆虫家蝇(Musca domestica L.)的幼虫,在我国分布极其普遍,具有易于孵育,饲养成本低,可集约化大规模养殖之特性。蝇蛆油GC-MS分析结果表明,蝇蛆油脂不饱和脂肪酸含量为56.79%,其中单不饱和脂肪酸占42.58%,多不饱和脂肪酸占14.21%。文中以酸催化酯化降酸预处理和碱催化酯交换两步法利用家蝇蛆油合成生物柴油,在酯交换中,反应温度为50℃、醇油比为5∶1、催化剂质量为总质量的1.25%、反应时间为45 min的条件下,得到了脂肪酸甲酯含量为85.46%的生物柴油。采用家蝇蝇蛆合成生物柴油作为生物能源的新原料与新途径,具有很高的工业适用性与可操作性。     

煤泥燃烧产物析出特性的热重-质谱联用分析

为研究含水率和升温速率对煤泥燃烧产物析出特性的影响,采用热重-质谱联用系统对煤泥进行燃烧实验,重点研究了5种含水率和3种升温速率条件下CO、CO_2、NO、NO_2的析出特性。实验结果表明:CO析出主要发生在焦炭燃烧阶段,CO_2、NO、NO_2在挥发份和焦炭燃烧阶段均有析出,析出温度范围分别在300～360℃和360～680℃;含水率对燃烧产物的析出特性影响较小;升温速率对燃烧产物析出有明显影响,随着升温速率增加,CO、CO_2、NO、NO_2的析出强度均增大,析出峰值温度均向高温区移动。     

HZSM-5/MCM-41复合分子筛的制备及其对竹木热解的影响

为了研究介微孔复合分子筛HZSM-5/MCM-41在生物质快速催化热解过程中的协同作用,以竹木为生物质原料,通过裂解气相色谱/质谱联用仪(Py-GC/MS)进行竹木热解实验和在线数据分析,研究不同消解时间-结晶时间和制备温度下复合分子筛HZSM-5/MCM-41对于竹木热解产物的影响。研究结果表明:在总时间一定的基础上,随着消解时间的增加,烃类物质的产率先升高后降低,当消解时间-结晶时间为24 h-24 h时,烃类物质的产率最高;随着制备温度的升高,烃类物质的产率先升高后降低,当制备温度为110℃时,烃类物质的产率达到最高;添加复合分子筛后,除了单环芳烃类物质的产率有极大提高外,酸类、呋喃类、酚类、酮类等含氧化合物的产率均有一定程度的下降;在竹木热解过程中添加复合分子筛HZSM-5/MCM-41有利于热解油品位的提高。     

泡桐在水中无催化直接液化生物油的GC-MS分析研究

使用气相色谱-质谱(GC-MS)法,分离和鉴定了泡桐在间歇反应釜中以水为溶剂直接液化制得的生物油的化学成分。用峰面积归一化法分别对水相二氯甲烷可溶物(轻油)和油相丙酮可溶物(重油)检索图谱库,得出各化合物在生物油中的百分含量。研究结果表明:轻油中鉴定出81种组分,其中含量0.6%的有33种且这33种成分的总含量为87.12%,轻油中主要组成为酚类、酮类、脂肪酸及芳香酸、呋喃衍生物、酯和醛;重油中鉴定出100种组分,其中含量0.6%的有37种且这37种成分的总含量为78.66%,重油中主要组成为酚类衍生物、分子量较大的酮类、脂肪酸、芳香酸、酯、苯衍生物和醛。因此,生物油的GC-MS法分析结果为其在化工和能源方面的综合利用提供了基础资料。     

水煤浆快速热解特性及影响因素研究

为研究水煤浆（CWS）的快速热解特性,利用高频加热炉,以神木煤作为CWS制作原料,开展快速热解实验,并与慢速热解实验结果作对比,分析了热解气的释放规律（产率、组分及比例等）及热解特性与反应温度、加热速率、停留时间之间的关系。结果表明：热解气以H2、CO、CH4和CO2成分为主;在高于1 000 ℃和较长的反应时间下进行快速热解,有利于生成高体积分数和高产率的还原性气体;快速热解条件下,随着温度的升高,H2和CO的产率持续增加（H2的产率增加了约0.45 L/g, CO的产率增加了约0.14 L/g）,而CH4的产率先上升后下降（在900 ℃时产率最高为0.12 L/g）,CO2产率在低温段有些许上升之后几乎没有明显变化（只增加了约0.03 L/g）;快速热解条件下,H2和CO的相对体积分数随着温度的升高而持续增加（分别增加了约45%和5%）,CH4和CO2的体积分数则随温度的升高而下降（CH4下降约35%,较为剧烈,而CO2则下降了约10%~20%）;在慢速热解时,H2,CO2和CH4的产率会随着最终温度的增加,呈先上升后下降的趋势（最高点在约1 100 ℃）,CO产率则呈上升趋势;慢速热解阶段H2和CO2的相对体积分数随着温度的增加略有变化（CH4则下降了3%）, CO增加约5%。     

煤热解过程气体停留时间的影响

在自制鼓泡流化床应器上进行了气体停留时间对煤热解过程影响的研究,研究发现焦油产在气体停留时间18．2s时最高,以后随气体停留时间的延长而下降,这是由于两个相反趋势共同作用的结果,在24.4s时煤气中高热值的烃类产量较闹,低热值CO与H2总产量较低,所以此时煤气热值较高,气体停留时间增加,半焦中残留挥发分减少H／C下降。通过适当调节载气流量,控制气体停留时间,可改善热解产物质量。     

脱硝尿素热解系统炉内烟气换热器运行分析及设计优化

脱硝尿素热解制氨系统一般通过电加热器提供所需的高温热解空气热量,采用锅炉烟道内布置烟气换热器,可以有效提供高温热解空气加热所需热量,降低电加热器运行功率从而节省高品质电能.通过对某350 MW机组实际运行数据分析,总结锅炉内置烟气换热器尿素热解系统的运行特点,提出烟气换热器优化设计方案,保证尿素热解制氨系统的运行经济性...     

Pyrolytic liquid fuel: A source of renewable electricity generation in Makkah

Millions of Muslims from all over the world visit the Holy Cities of Saudi Arabia: Makkah and Madinah every year to worship in form of Pilgrimage (Hajj) and Umrah. The rapid growth in local population, urbanization, and living standards in Makkah city along with continually increasing number of visitors result in huge municipal solid waste generation every year. Most of this waste is disposed to landfills or dumpsites without material or energy recovery, thus posing substantial environmental and health risks. The municipal plastic waste is the second largest waste stream (up to 23% of total municipal waste) that is comprised of plastic bottles, water cups, food plates, and shopping bags. The sustainable disposal of plastic waste is challenging task due to its clogging effects, very slow biodegradation rates, and presence of toxic additives and dyes. Pyrolysis is one of the promising waste-to-energy technology for converting municipal plastic waste into energy (liquid fuel) and value-added products like char. The produced liquid fuel has the potential to be used in several energy-related applications such as electricity generation, transportation fuel, and heating purposes. It has been estimated that the plastic waste in Makkah city in 2016 can produce around 87.91 MW of electricity. This is projected to increase up to around 172.80 MW of electricity by 2040. A global warming potential of 199.7 thousand Mt.CO₂ eq. will be achieved with savings of 7.9 thousand tons emission of CH₄, if pyrolysis technology is developed in Makkah city. Furthermore, a total savings of 297.52 million SAR from landfill diversion, electricity generation, and carbon credits would be possible to achieve in 2016 from pyrolysis. These economic benefits will increase every year and will reach up to 584.83 million SAR in 2040.     

Analysis of reaction mixtures of perhydro-dibenzyltoluene using two-dimensional gas chromatography and single quadrupole gas chromatography

Energy storage via liquid organic hydrogen carrier (LOHC) systems has gained significant attention in recent times. A dibenzyltoluene (DBT) based LOHC offers excellent properties which largely solve today's hydrogen storage challenges. Understanding the course of the dehydrogenation reaction is important for catalyst and process optimization. Therefore, reliable and exact methods to determine the degree of hydrogenation (doh) are important. We here present other possible techniques, namely: comprehensive two-dimensional gas chromatography coupled with time of flight mass spectrometry (2D-GC-TOF-MS) and single quadrupole-mass spectrometry gas chromatogram system (GC-SQ-MS). The 2D-GC-TOF-MS results indicate that isomer fractions lose three molecules of hydrogen, as follows: H18-DBT, H12-DBT, H6-DBT and H0-DBT, and the doh decreases with an increase in dehydrogenation temperature. ¹H NMR and GC-SQ-MS were employed as additional analytical techniques. The GC-SQ-MS was also used to analyse decomposition products that result from thermal cracking of reaction mixture molecules.     

Effects of Fe2O3 on pyrolysis characteristics of soybean protein and release of NOx precursors

The effects of ferric oxide (Fe₂O₃) on the pyrolysis characteristics of soybean protein and the release of precursors to nitrogen oxides (NOx) were studied using thermogravimetry and mass spectrometry. The results show that, as the content of Fe₂O₃ increases, there is no major difference between initial and peak temperatures of protein pyrolysis samples. Moreover, between the temperature range of 204 and 550°C where weight loss mainly occurs, total weight-loss rate decreases before increasing, with obvious weight loss occurring around the temperature of 650°C. Fe₂O₃ displays both inhibiting and promoting effects on the precipitation of nitrogen-containing gases such as ammonia (NH₃), hydrogen cyanide (HCN), isocyanic acid (HNCO), and acetonitrile (CH₃CN), with the inhibition effect prevailing over promotion effect on the whole.     

Numerical study of conduction and radiation heat losses from vacuum annulus in parabolic trough receivers

Parabolic trough receiver is a key component to convert solar energy into thermal energy in the parabolic trough solar system. The heat loss of the receiver has an important influence on the thermal efficiency and the operating cost of the power station. In this paper, conduction and radiation heat losses are analyzed respectively to identify the heat loss mechanism of the receiver. A 2-D heat transfer model is established by using the direct simulation Monte Carlo method for rarefied gas flow and heat transfer within the annulus of the receiver to predict the conduction heat loss caused by residual gases. The numerical results conform to the experimental results, and show the temperature of the glass envelope and heat loss for various conditions in detail. The effects of annulus pressure, gas species, temperature of heat transfer fluid, and annulus size on the conduction and radiation heat losses are systematically analyzed. Besides, the main factors that cause heat loss are analyzed, providing a theoretical basis for guiding the improvement of receiver, as well as the operation and maintenance strategy to reduce heat loss.     

Analysis of rationality of coal-based synthetic natural gas (SNG) production in China

To alleviate the problem of the insufficient reserves of natural gas in China, coal-based synthetic natural gas (SNG) is considered to be a promising option as a source of clean energy, especially for urban use. However, recent study showed that SNG will not accomplish the task of simultaneous energy conservation and CO₂ reduction. In this paper, life cycle costing is made for SNG use in three main applications in residential sector: heating, household use, and public transport. Comparisons are conducted between SNG and coal, natural gas, liquefied petroleum gas (LPG), diesel, and methanol. The results show that SNG is a competitive option only for household use. The use of SNG for heating boilers or city buses is not as cost-effective as expected. The biggest shortcoming of SNG is the large amount of pollutants generated in the production stage. At the moment, the use of SNG is promoted by the government. However, as shown in this paper, one can expect a transfer of pollution from the urban areas to the regions where SNG is produced. Therefore, it is suggested that well-balanced set of environmental damage-compensating policies should be introduced to compensate the environmental losses in the SNG-producing regions.     

火力发电厂烟气脱硫系统电气设计分析

烟气脱硫（FGD）电气系统的主接线方式及系统构成特点,阐述了FGD电气系统的接地技术,分析了事故保安负荷在FGD电气系统中的作用,提出了设计中应注意的事项。     

Reduction of fuel consumption in gasoline engines by introducing HHO gas into intake manifold

Brown’s gas (HHO) has recently been introduced to the auto industry as a new source of energy. The present work proposes the design of a new device attached to the engine to integrate an HHO production system with the gasoline engine. The proposed HHO generating device is compact and can be installed in the engine compartment. This auxiliary device was designed, constructed, integrated and tested on a gasoline engine.