Experimental assessment of a plasma-catalyst hybrid reformer for hydrogen production via partial oxidation of dimethyl ether

In this work,hydrogen is produced from partial oxidation reforming of dimethyl ether （DME） by a plasma-catalyst hybrid reformer under atmospheric pressure.The plasma-catalyst hybrid reformer which includes both plasma and catalyst reactors is designed.A spark discharge is used as a non-equilibrium plasma source,and it is used to ionize the mixture of DME and air.The performances of the reformer are characterized experimentally in terms of gas concentrations,hydrogen yield,DME conversion ratio,and specific energy consumption.The effects of discharge frequency,reaction temperature,air-to-DME ratio and space velocity are investigated.The experimental results show that the plasma-catalyst hybrid reformer enhances hydrogen yield when reaction temperature drops below 620 ℃.At 450 ℃,hydrogen yield of hybrid reforming is almost three times that of catalyst reforming.When space velocity is 510 h-1,hydrogen yield is 67.7%,and specific energy consumption is 12.2 k J/L-H2.     

合成气直接制二甲醚的Cu基双功能催化剂研究

为对催化研究和二甲醚的实际生产提供参考,采用共沉淀沉积法制备了一系列CuO/ZnO/ZrO2/MnO2/HZSM-5比例不同的二甲醚合成催化剂,并在固定床高压流动反应装置上,以自制的含氮合成气(V(H2)∶V(CO)=2.13)为原料考察了催化剂制备条件和组分比例对催化剂性能的影响.结果表明,当共沉淀温度在75℃、pH值在10左右,n(CuO)∶n(ZnO)∶n(ZrO2)∶n(MnO2)=1∶1∶0.5∶0.01、m(MnO2-(CuO-ZnO-ZrO2)∶m(HZSM-5)=3∶1时,催化剂的活性和选择性最好,在反应压力为4.0 MPa,原料空速为1 000 h-1,反应温度为250℃时,CO转化率达到87.81%,二甲醚收率达到65.07%.TPR、XRD、XPS等测试结果表明,在MnO2-(CuO-ZnO-ZrO2)/HZSM-5催化剂中,ZnO能提高CuO组分的分散度,使活性中心增加,并与MnO2协同作用,促进电子传递,增强了催化剂的活性和选择性.     

生物甘油水蒸气重整制氢强化过程的参数评估

为深入分析生物甘油水蒸气自热重整制氢强化过程以实现高效制氢,采用吉布斯自由能最小原理,研究氢气分离与二氧化碳吸附两种强化手段对甘油自热重整过程的影响,分析氢气产量、积碳量与反应热随温度、氢气分离系数等参数的变化规律.结果表明:氢气的分离会大大提高氢气的产量,抑制甲烷的生成,但会导致积碳量增加.氢分离会增加对反应热的需求,为达到自热,需要更高的氧气-甘油投料比.氧化钙作为二氧化碳吸附剂,在750 K以下由于生成氢氧化钙而降低氢气的产量;当温度高于800 K时,碳酸钙分解会降低吸附剂对二氧化碳的吸附能力,故氧化钙的吸附温度应控制在750~800 K.二氧化碳吸附所放出的热量可以使甘油重整实现自热.     

二甲醚发动机低压共轨燃料喷射系统的设计及试验

针对二甲醚燃料低粘性、高蒸汽压以及容易与空气形成混合气的特性,设计了一种可控预混合燃烧的二甲醚发动机低压共轨电控燃油喷射系统.在此基础上,以柴油代替二甲醚进行试验,分析了在喷射持续期,共轨压力、针阀升程和转速对燃油喷射过程的影响,得出了低压共轨燃料系统的燃料喷射特性,对二甲醚低压共轨系统的实用化起到了促进作用.     

多孔纤维型重整微反应器的等效电阻网络建模

针对应用于重整制氢微反应器的复杂多孔金属纤维载体（PFS）的流速场高效分析难题,建立载体中随机微通道的等效电阻网络分析模型. 基于复杂随机纤维结构的统计网络模型,将纤维载体中三维联通的随机微通道结构及与之相连的进出口腔简化为规则的网络通道结构.借鉴基尔霍夫定律,建立纤维载体的等效电阻网络模型,并确定求解方法. 纤维载体流速场实例分析的结果表明,基于等效电阻网络模型求解的纤维载体流速场与计算流体力学(CFD)方法的结果之间的皮尔森相关系数约为98%,且求解效率约为CFD方法的2.9×10⁴倍. 研究成果为多孔纤维型重整制氢微反应器的设计制造提供了新的支撑方案.     

Development of an Internally Circulating Fluidized Bed Membrane Reactor for Hydrogen Production from Natural Gas

An innovative Internally Circulating Fluidized Bed Membrane Reactor (ICFBMR) was designed and operated for ultra-pure hydrogen production from natural gas. The reactor includes internal catalyst solids circulation for conveying heat between a reforming zone and an oxidation zone. In the reforming zone, catalyst particles are transported upwards by reactant gas where steam reforming reactions are taking place and hydrogen is permeating through the membrane surfaces. Air is injected into the oxidation zone to generate heat which is carried by catalyst particles to the reforming zone supporting the endothermic steam reforming reaction. The technology development process is introduced: cold model test,pilot plant and industrial demonstration unit. The process flow diagram and key components of each unit are described.The ICFBMR process has the potential to provide improved performance relative to conventional SMR fixed-bed tubular reactors.     

模拟淀粉废水厌氧发酵生物制氢

采用连续流和静态试验进行了模拟淀粉废水厌氧发酵法生物制氢,探讨了有机负荷（OLR）和pH值对产氢能力和液相末端产物的影响。在连续流反应器中,发酵气体产量和氢产量随负荷的增加而升高;当发酵类型为乙醇型,pH 3.9,有机负荷率为22.0 kg COD/(m3·d)时可同时获得最大气体产量和氢气产量;最大比氢产率为87.5?ml H2/g淀粉。在静态试验中,初始pH值在3.5～4.3时,氢气产量随着pH值增加而增加;pH值范围在4.3～5.0时氢气产量先是下降随后保持稳定,pH?4.3时获得最大氢气产量,最大比氢产率为80?ml H2/g淀粉。结果表明,淀粉废水可以作为厌氧发酵法生物制氢底物。     

生物质制氢研究进展

在人类面临严重的能源危机与环境污染的背景下,生物质制氢是一项富有前景的制氢技术,已引起了世界各国研究者的普遍关注．主要介绍了目前国内外生物质制氢的研究现状和发展中存在的问题,为我国生物质能的发展和使用提供参考．     

Study on Production of Hydrogen from Methane for Proton Exchange Membrane Fuel Cell

The hydrogen production from methane for proton exchange membrane fuel cell (PEMFC) was studied experimentally. The conversion rate of methane under different steam-carbon ratios, the effect of the different excess air ratios on the constituents of the gas produced, the permeability of hydrogen under different pressure differences, and the effect of different system pressure on the reaction enthalpy of hydrogen were obtained. The results lay the basis for the production of hydrogen applicable to PEMFC, moreover, provide a new way for the comprehensive utilization of the coal bed methane.     

二甲基硫醚废气的处理

研究二甲基二硫醚的废气处理 ,利用双氧水在 30～ 4 0℃下反应约 3.5～ 4 .0h氧化成二甲基亚砜 ;废气中的二甲基二硫醚回收送入二甲基二硫醚精馏塔中 .产生的二甲基亚砜可以制成成品用于销售 ,达到处理废气的目的 .本文探讨了工艺路线、反应溶剂、反应温度、反应物比例、双氧水的滴加量、反应时间、搅拌速度等对反应的影响 ,一次性的产率可达 85 % .     

甲烷催化裂解制氢气的研究

甲烷制氢有很多种方法,而其中甲烷催化裂解制氢因其耗能少、不产生COx而成为一种较有前景的方法。文章从提高甲烷制氢转化率着手,介绍了操作条件如反应器形式、反应时间、温度、流速等及催化荆活性碳尺寸对反应的影响。另外,介绍了副产品碳的可能应用领域。     

系列水滑石化合物催化KBH_4水解析氢的活性研究

采用共沉淀法、强碱水热法及尿素水热法合成Ni/Al、Mg/Al、Zn/Al、Ni/Fe、Zn/Fe、Zn/Cr、Co/Fe等七个系列水滑石类化合物并将其用于催化KBH4水解析氢,催化析氢结果表明:Ni/Al组分活性最高,从合成方法的角度看:尿素水热法强碱水热法共沉淀法.     

一株分离自潮间带污泥细菌Clostridium sp. T7产氢特性分析

产氢菌株Clostridium sp. T7分离自天津海水浴场潮间带的污泥.研究起始pH、碳源、氮源、NaCl质量分数对菌株T7产氢性质的影响.结果表明：菌株T7最适产氢的起始pH是6.0,能够利用蔗糖、葡萄糖和果糖等碳源发酵产氢.菌株T7能够利用牛肉膏和酵母粉为单一氮源产氢,不能利用蛋白胨为氮源进行产氢.NaCl质量分数能影响菌株T7的产氢量,海水培养条件（NaCl质量分数为3%）下,最高产氢量是每摩尔葡萄糖（1.48,±0.05）mol,相比之下,淡水培养条件下其产氢量提高20%.NaCl质量分数在0.4%～7%时,菌株T7都能够产氢,这表明菌株T7有望应用于淡水或高盐有机废水产氢领域.     

不同来源污泥对稻草发酵产氢影响的研究

讨论了不同来源的混合菌群、不同的接种方式以及单一菌种产气肠杆菌对稻草发酵产氢的影响.相对于混合菌群，单一纯菌产气肠肝菌在氢气产量上处于劣势.对于取自同一沼气池的厌氧活性污泥，经煮沸后扩大培养的混合菌群作为接种物，经过NaOH预处理后稻草的单位产氢量为91.5 mL/g，最高产氢速率为1.52 mL/(h·g)；以直接扩大培养的污泥作为接种物，经过NaOH预处理后稻草的单位产氢量为62.5 mL/g，最高产氢速率为1.04 mL/(h·g).对3种混合菌群均采用直接扩大培养的接种方法，其总产氢气量为：沼气池污泥（62.5 mL/g）<污水处理厂污泥（69.5 mL/g）<湖底污泥（80.5 mL/g）.     

富含三类大分子有机质的废弃食物发酵产氢特性

以富含大分子碳水化合物、蛋白质和脂肪的5种废弃食物为发酵底料，采用厌氧活性污泥为接种物，研究了其发酵产氢特性，并利用色谱仪分析了发酵产物的气相和液相组成.结果表明，米饭、马铃薯、青菜、瘦猪肉和肥猪肉发酵生成的H2与CO2的体积比分别为0.77、0.82、0.82、0.93和0.82，H2与CH4的体积比均高于4，有些甚至没有CH4产生.将厌氧活性污泥加热预处理能够有效抑制产甲烷菌，同时又保持产氢菌芽孢的活性.在米饭、马铃薯和肥猪肉发酵生成的脂肪酸中丁酸的体积分数最高；在瘦猪肉发酵液中乙醇的体积分数最高；而在青菜发酵液中乙酸、丙酸和丁酸的体积分数相当.     

生物制氢反应器不同发酵类型产氢能力的比较

对生物制氢反应器乙醇型发酵和丁酸型发酵的产氢能力及其生态学特性进行了对比分析.结果表明,NADH/NAD 平衡调节是影响不同发酵类型产氢差异的主要原因.在有机负荷为40 kg/(m3.d)条件下,乙醇型产酸发酵菌群表现出较高的产氢能力,最大比产氢速率为550 m l/(gVSS.d),是丁酸型产酸发酵菌群比产氢速率的3.3倍.综合两种发酵类型特性、运行操作条件和制氢成本考虑,乙醇型发酵更适合作为生物制氢工业化生产的发酵类型.     

流化床膜反应器甘油强化重整的数值模拟

为实现生物柴油副产物甘油在制氢行业的发展,以流化床甘油重整制氢为研究对象,基于双流体模型和颗粒动力学理论,结合甘油重整反应动力学模型,并嵌入二氧化碳吸附动力学模型和氢气膜分离模型来描述两种强化重整方法的作用. 对流化床反应器生物甘油强化重整制氢过程开展了数值模拟,对反应器内颗粒浓度、组分浓度、温度进行预测,探究重整过程中气固两相流动与反应特性,分析氢气膜分离和二氧化碳吸附两种强化重整方法的相互作用规律,评价操作参数对重整性能的影响. 结果表明:二氧化碳吸附可以抑制浓度极化阻力,提高氢气渗透速率;吸附剂与催化剂比例为1∶1时,与没有吸附剂相比,氢气相对产量提高了5%;氢气分离膜厚的减少会进一步提高二氧化碳吸附速率,当膜厚从300 μm减少到30 μm时,吸附速率提高1.4%;催化-吸附双功能颗粒的使用可以加强二氧化碳的吸附水平,同时促进氢气分离过程,相较于无吸附强化,氢气渗透量提高了近20%.     

Development and Improvement of Bioreactor for Fermentative Hydrogen Production

The paper reviewed hydrogen production biotechnology on reactor development and design aspects. Biological hydrogen-producing reactor as acid-producing phase of two-phase anaerobic organism treatment system plays an important role in the following aspects: Reactor was developed as the follow ideas: 1) CSTR-type anaerobic fermentation reactor is selected to reduce the substrate concentration in reactor and increase target product operational yield and selectivity in the reactor;2)Integration structure with mixing reaction area and deposit-separating area is selected, i.e. gas-liquid-solid phase separation unit; 3)Mixture liquid in reaction area is stirred by the stirrer to reach a turbulent state in order to reduce interfacial layer thickness and temperature gradient in a floc unit particle and increase mass transfer rate;4) H2 in the particle and liquid phase is accelerated to release to prevent accumulated H2 from bringing feedback inhibition to organism metabolism, and H2/CO2conversion to acetic acid; 5) A sector turbine agitator with hoisting capacity and mixing power is selected to facilitate sludge to flow back through a effluence seam; 6 ) Interior wall in the reaction area is equipped with vertical baffles to avoid causing swirling flow of mixture liquid owing to agitation.     

Catalytic effects of trace ruthenium on oxidation of dimethyl yellow with bromate and its application

A spectrophotometric method for the determination of ruthenium(Ⅲ) is described, based on its catalytic effect on the oxidation reaction of dimethyl yellow (DMY) with potassium bromate in an acid solution medium and in the presence of an OP emulsifier (p-iso-octyl phenoxy polyethoxy ethanol) at 100 ℃. This reaction was followed spectrophotometrically by measuring the decrease in the absorbance at 530 nm of the catalytic reaction of DMY. The calibration curve for the recommended method was linear in the concentration range over 0.0-1.0 μg/Land the detection limit of the method for Ru(Ⅲ) was 0.01 μg/L. The method is highly sensitive, selective and very stable and has been successfully applied for the determination of trace amounts of ruthenium in some ores and metallurgy products with the relative standard deviations (RSD) over 1.6%-2.8% and a recovery over 98.7%-104.0%.     

薄层色谱法（TLC）定量分析二乙二醇单丁醚

以乙酸乙酯／丙酮／水为展开剂，乙二醇单丁醚生产过程中产生的残液中各主要组分可在硅胶板上获得分离，由此建立起薄层色谱法（ＴＬＣ）测定残液中二乙二醇单丁醚含量的方法．