EXTERNAL-LOOP AIRLIFT MAGNETICALLY STABILIZED BED--MINIMUM STABILIZATION AND FLUIDIZATION CONDITIONS

Experimental study of an airlift with a magnetically stabilized bed in the riser bottom has been performed. External magnetic field allows easy control of magnetized bed structure and liquid circulation rate. Minimum stabilization and fluidization conditions have been determined experimentally and by a three-line graphical method. Semi-empirical data correlations of sections of the experimental curves have been performed. Scaling relationships known from non-magnetic airlift are applicable too, but with the assumption that the magnetic field affects the loop friction coefficient only.

Formation and properties of high Fe-content Fe-(B-Si)-Zr bulk amorphous alloys

The present work is devoted to the development of Fe-（B-Si）-Zr amorphous alloys with high glass-forming ability and good magnetic properties. Using the cluster-plus-glue-atom model proposed for ideal amorphous structures, [FeFe11B3Si]（Fe1-xZrx） was determined as the cluster formula of Fe-（B-Si）-Zr alloys. The glass formation and thermal stability of the serial alloys, namely, [FeFel^B3Si]（Fel_xZrx） （x = 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.75, and 1.0）, were studied by the combination of copper mold casting, X-ray diffraction, and differential thermal analysis techniques. The maxima of glass-forming ability and thermal stability were found to occur at the compositions of [FeFe11B3Si] （Fe0.6Zr0.4） and [FeFe11B3Si]（Fe0.5Zr0.5）. The alloys can be cast into amorphous rods with 1.5 ram diameter, and upon reheating, the amorphous alloys exhibit a large undercooled liquid span of 37 K. The saturation magnetization of the [FeFe11B3Si]（Fe0.5Zr0.5） amorphous alloy was measured to be 1.4 T.

Thermal Stability and Magnetic Properties of (Fe,Co)-Zr-Nd-B Amorphous Alloys

A new type of Fe-based amorphous alloy containing rare earth element was prepared by melt spinning technique. The glass-forming ability (GFA),thermal stability and magnetic properties were investigated in the composition range of Fe_(70)Co_8Zr_(7- x )Nd_ x B_(15) ( x =0% to 6%,atom fraction). They exhibit the glass transition and supercooled liquid region before crystallization. The width of supercooled liquid region obtained for the series of Fe_(70)Co_8Zr_(7- x )Nd_ x B_(15) exceeds (40 K,) among which the maximum width for Fe_(70)Co_8Zr_5Nd_2B_(15) amorphous alloy reaches 61 K. Another main attraction is that the selected Fe-based amorphous alloys have good soft magnetic properties. The saturation magnetization ( J _s) is in the range of 1.10 to 1.37 T,and coercive force ( H _c) in the range of 2.28 to 8.15 A·m (-1) for Fe_(70)Co_8Zr_(7- x )Nd_ x B_(15) amorphous alloys. It is found that the saturation magnetization ( J _s) increases with the increment of the relative content of the Nd for the Fe_(70)Co_8Zr_(7- x )Nd_ x B_(15) alloys. The H _c values for the glasses with Nd content of 1%,2% and 3% are below 3 A·m (-1). The research indicates that Fe_(70)Co_8Zr_5Nd_2B_(15) amorphous alloy has good high GFA and good soft magnetic properties,of which the width of supercooled liquid region,J _s,and H _c are 61 K,1.25 T and 2.28 A·m (-1),respectively.

Magnetically stabilized bed reactor for selective hydrogenation of olefins in reformate with amorphous nickel alloy catalyst

A magnetically stabilized bed （MSB） reactor for selective hydrogenation of olefins in reformate was developed by combining the advantages of MSB and amorphous nickel alloy catalyst. The effects of operating conditions, such as temperature, pressure, liquid space velocity, hydrogen-to-oil ratio, and magnetic field intensity on the reaction were studied. A mathematical model of MSB reactor for hydrogenation of olefins in reformate was established. A reforming flow scheme with a post-hydrogenation MSB reactor was proposed. Finally, MSB hydrogenation was compared with clay treatment and conventional post-hydrogenation.

High-pressure sintering and magnetic properties of Fe_(86)Zr_(11-x)Nb_xB_3(x=5.5, 6) amorphous alloys

The thermal stability of milling Fe86Zr11-xNbxB3（x=5.5, 6） melt-spun strip powders and the influence of high-pressure sintering conditions on phase component and grain size of bulk alloys were investigated by X-ray diffractometry（XRD）, differential scanning calorimetry（DSC） and scanning electron microscopy（SEM）. The results show that milling melt-spun powder remains in the amorphous state, and the crystallization temperature of which is 480530℃, the apparent activation energy Ep of crystallization process is 294.1219.5kJ/mol. The increasing Nb content can increase crystallization temperature and decrease Ep. Under the sintering conditions of 5.5GPa/3min, when Pw is 1150W, single phase α-Fe nanocrystalline （20.626.7nm） bulk alloy with relative density higher than 99.0% can be obtained. Under the sintering conditions of 5.5GPa/1150W/3min, the magnetic properties of these nanocrystalline bulk alloys are Fe86Zr5.5Nb5.5B3 alloy, Bs=1.15T, Hc=5.08kA·m-1; Fe86Zr5Nb6B3 alloy, Bs=1.26T, Hc=4.27kA·m-1.

Collecting aerosol in airflow with a magnetically stabilized fluidized bed

A magnetically stabilized fluidized bed (MSB) is a highly efficient filter that takes the advantage of both fluidized beds and fixed beds. This paper presents the research to collect aerosol in airflow with a MSB. The filtering model of MSB is established with its parameters including magnetic Geld intensity, gas superficial velocity, average grain-size, and bed height on the collection efficiency of MSB. The model is verified by experiments.

Removal of dust from flue gas in magnetically stabilized fluidized bed

A magnetically stabilized fluidized bed （MSFB,Ф 500mm×2100mm） was designed to study dust removal from flue gas. Based on the mechanism of dust removal in a fixed bed, the effects on collection efficiency of magnetic field intensity, ratio of flue gas velocity to minimum fluidization velocity, bed height, and particle average diameter, were investigated. Then feasible methods for MSFB to better remove dust were proposed. Over 95 % of dust removal with MSFB can be achieved, when stable fluidization is maintained and when magnetic particles are frequently renewed.

尼龙-6单体己内酰胺绿色生产技术

中石化石油化工科学研究院有限公司历经30年持续创新,成功开发尼龙-6单体己内酰胺绿色生产技术,主要包括:环己烯酯化加氢制环己酮绿色合成新途径,空心TS-1分子筛与浆态床集成用于环己酮氨肟化,S-1分子筛与移动床集成用于环己酮肟气相贝克曼重排,非晶态镍催化剂与磁稳定床集成用于己内酰胺精制。与引进己内酰胺生产技术相比,碳原子和氮原子利用率明显提升,三废排放显著减少,无副产低价值硫酸铵,装置投资大幅下降,生产成本明显减少。

Local heat transfer properties in co- and counter-current G-L-S magnetically stabilized fluidized beds

Heat transfer coefficients were measured by immersed probes in co- and counter-current G-L-S magnetically stabilized fluidized beds （MSFBs） using air, water and nickel-alloy particles as the gas, liquid and solid phases. Influences of major factors, including magnetic field intensity, superficial gas and liquid velocities, liquid viscosity and surface tension, on heat-transfer properties were studied experimentally, indicating that both co- and counter-current G-L-S MSFB can provide relatively uniform radial distribution of heat transfer coefficients under appropriate operation conditions, thus controlling operation temperature for highly exothermic multi-phase reaction systems. Two correlations were provided to estimate accurately heat transfer properties in both co- and counter-current G-L-S MSFB systems, with an average error of less than 10%.

High-efficiency removal of NOx by a novel integrated chemical absorption and two-stage bioreduction process using magnetically stabilized fluidized bed reactors

To enhance the bioregeneration of Fe(II)EDTA and to avoid the inhibition of the components in nitrogen oxides(NOx) scrubbing solution, a novel integrated process of metal chelate absorption and two-stage bioreduction was developed. In this process, magnetically stabilized fluidized beds(MSFB) were used as the bioreactors, and the phase diagram for the MSFB operation was determined. Factors including inlet NO, O2 and SO2 concentrations, magnetic field intensity, gas flow rate and liquid circulation rate, were studied experimentally to investigate their effects on NO removal. In addition, a mathematical model for NO removal in this integrated system was developed. The results revealed that the integrated system could be steadily operated with a high NO removal efficiency and elimination capacity, even under the condition of high NO and O2 shock-loading. The established model showed that NO removal efficiency was related to the spray column property and the active Fe(II)EDTA concentration, while the latter depends on the bioregeneration of the disabled absorbent in the MSFB.

磁稳定床反应器中己内酰胺加氢精制过程研究

对以非晶态合金 (SRNA- 4 )为催化剂的磁稳定床己内酰胺加氢精制过程进行了研究 ,研究了各种操作参数对反应结果的影响 ,考察了催化剂的稳定性 ,建立了反应器模型。实验结果表明 ,在磁稳定床反应器中对己内酰胺水溶液加氢精制 ,可使己内酰胺水溶液的 PM值从 10 0 s提高到 30 0 0 s以上 ,催化剂寿命 135 0h;与工业上搅拌釜式己内酰胺加氢精制工艺相比 ,催化剂耗量可降低 5 0

镍基非晶态合金加氢催化剂与磁稳定床反应器的开发与工业应用

报道了开发镍基非晶态合金加氢催化剂的实验室研究、中试研究及工业应用研究结果。向非晶态合金中加入少量原子半径大的其他元素 ,使非晶态合金的晶化温度由 36 0℃提高到 5 2 0℃ ;在含镍非晶态合金中加入铝 ,然后用碱将铝抽出 ,使非晶态合金比表面积由 1m2 /g增加到 10 0m2 /g以上 ;在建立 30t/a非晶态合金生产示范装置中 ,自行设计了特殊的喷嘴和选用适宜的坩埚材质 ,使生产成品率由 2 0 %左右提高到 93%以上 ,利用副产的偏铝酸钠 ,合成NaY分子筛 ,形成了整体的清洁生产过程 ;重点介绍了非晶态合金加氢催化剂经在三个工厂工业应用成功 ,三项工业应用成果每年为企业创造直接效益 6 70 0万元。还报道了对磁稳定床反应器的研究开发 ,经在2 0kt/a磁稳定床加氢示范装置上 35 0 0h试验 ,其生产效率比釜式加氢过程提高 4倍 ,催化剂消耗减少 5 0 %。

磁稳定床反应器中己内酰胺加氢精制应用研究

采用工业原料在6 kt/a中试装置上对以镍系非晶态合金为催化剂的磁稳定床反应器中己内酰胺的加氢精制过程进行了研究,考察了各种操作参数对反应结果的影响以及催化剂的稳定性。试验结果表明,己内酰胺水溶液经预溶氢后磁稳定床反应器加氢精制或气液固三相磁稳定床反应器加氢精制,在氢液体积比0.7-1.5、反应温度80-100℃、反应压力0.4-0.9 MPa、空速30-50 h-1、磁场强度15-32 kA/m的条件下,加氢后溶液的高锰酸钾值(PM)从50 s提高到2 000 s以上,催化剂寿命达3 200 h以上;与工业上搅拌釜式己内酰胺加氢精制工艺相比,催化剂耗量可降低60％。

液固磁稳定床流体力学特性

The hydrodynamic characteristics of liquid-fluidized magnetically stabilized beds (MSB) with commercial amorphous nickel alloy catalyst (SRNA-4) as solid phase and water as liquid phase in a cold model experimental apparatus of Φ140mm were investigated. The influence of magnetic field intensity on bed structure, pressure drop, minimum fluidization velocity, transition velocity, and liquid holdup were investigated. Mathematical models for minimum fluidization velocity, transition velocity, liquid holdup were established respectively. The operating phase diagrams of liquid-fluidized MSB with SRNA-4 catalyst of two different sizes were obtained.

磁稳定床己内酰胺加氢精制新工艺

对气液固三相搅拌釜反应器与液固磁稳定床反应器串联的己内酰胺加氢精制过程进行了研究,研究了各种操作参数对反应结果的影响,考察了催化剂的稳定性。实验结果表明,采用该工艺可使w(己内酰胺)=30%的水溶液的高锰酸钾值从50s提高到3000s以上,催化剂寿命3200h。与工业上釜式己内酰胺加氢精制工艺相比,催化剂耗量可降低70%。

新催化材料和化工过程强化——非晶态合金/磁稳定床反应器和负载型杂多酸/悬浮床催化蒸馏

介绍化工过程强化的两个新例 :磁稳定床反应器和悬浮床催化蒸馏过程。以细颗粒镍系非晶态合金为催化剂的磁稳定床反应器用于己内酰胺加氢精制的试验研究表明 ,与现有釜式工艺相比 ,加氢效率可提高 3～ 5倍 ,催化剂耗量降低 50 % ,并且可缩小反应器体积。新型悬浮床催化蒸馏用于负载型杂多酸催化的苯与丙烯、十二烯烷基化过程的研究表明 ,与常规固定床催化蒸馏相比 ,悬浮床催化蒸馏具有传质阻力小、催化效率高、烯烃转化率和烷基苯选择性高、投资及能耗低等优点。

非晶态Ni合金催化剂用于低温甲烷化反应的研究

采用非晶态Ni合金催化剂在磁稳定床上进行了原料气粗氢中含少量CO和CO2的甲烷化研究。试验结果表明,非晶态Ni合金催化剂具有优良的加氢性能,在温度160~200℃、压力01~30MPa、空速10000~100000h-1的条件下,能将原料气中少量的CO和CO2完全转化;120h稳定性实验表明,催化剂性能稳定,活性基本保持不变。

非晶态合金催化剂和磁稳定床反应工艺的创新与集成

创新的加氢技术包括非晶态合金催化剂和结合其磁性与加氢性能开发的磁稳定床反应工艺。将晶态催化剂的结构非晶化,使广泛应用的Raney Ni加氢性能产生质的飞跃。通过加入原子半径大的稀土提高晶化势能垒和碱抽提铝,突破了非晶态合金作为实用催化材料热稳定性差、比表面积小的限制。开发了工业生产非晶态合金催化剂的关键技术和设备,引入杂原子,调整对各种官能团的加氢活性、耐酸性和磁性,形成了SRNA系列催化剂。结合均匀磁场和非晶态合金的磁性,形成磁稳定床反应工艺。设计了调节磁场的磁隔栅;建立了可指导工业化的磁场和反应器数学模型。将该工艺用于己内酰胺加氢精制,催化剂耗量降低70%,反应器体积分别是相同处理量釜式和固定床的1/8和1/3,强化了催化反应过程。非晶态合金催化剂和磁稳定床反应工艺在国际上首次工业应用,使我国的加氢技术产生跨越式进步,并产生了巨大的经济和社会效益。

磁稳定床反应器重整生成油后加氢过程研究

对采用非晶态合金催化剂SRNA-4的磁稳定床重整生成油后加氢精制过程进行了研究,试验考察了各种条件对加氢效果的影响,找到适宜的反应条件为:反应温度80～120℃,压力1.0～1.5MPa,液时空速20～30h^(-1),氢油体积比20～100及磁场强度15～20kA/m。并建立了反应器模型。研究结果表明,在磁稳定床反应器中可以使重整生成油的溴值从2.0gBr/(100g)降到0.5gBr/(100g)以下,基本无芳烃损失,满足工业要求。磁稳定床重整生成油后加氢工艺与传统固定床后加氢工艺及白土精制工艺相比,具有催化剂装卸方便、反应条件缓和、空速大等优点。