低压甲醇脱硫系统综合技术改造

针对低压甲醇脱硫系统氧化再生槽大量飞泡现象，分析了造成飞泡的原因。通过综合技术改造，成功解决了飞泡问题，提高了脱硫及硫回收效率。     

调整工艺条件解决脱硫液飞泡问题

分析该厂改良ADA法脱硫液发生飞泡的原因，主要是由于脱硫液组份失调造成大量HS-无法转化为硫，初生态吸附大量HS-而成为稳定体系，使得硫颗粒细，难以回收而在溶液中累积，从而造成飞泡。采取针对性解决措施，取得了较好效果。     

喷淋式硫铵饱和器的生产操作

介绍喷淋式饱和器生产硫铵的工艺流程及生产操作数据，与鼓泡式饱和器相比，体现了喷淋式饱和器在设备投资、能源消耗和硫铵质量等方面的优越性。     

从铜浸出渣中浮选回收元素硫的研究

考查了适合浸出渣中元素硫浮选回收的理想工艺参数,并利用旋流-静态微泡浮选柱取得了良好的分选指标,最终精矿的元素硫品位达到56.08%,为铜浸出渣的合理利用探求了一种工艺简单、成本节约的新方法.     

硫黄回收装置液硫品质提升措施

针对硫黄回收装置液硫中H₂S含量不达标的问题进行分析，主要影响因素有低压蒸汽管网压力偏高、空气鼓泡管铺设不足、液硫循环喷射停运、液硫池废气排放流程限制等，提出了降低液硫中H₂S含量的措施。措施实施后液硫中H₂S含量合格率由94.2%提升至100%，保证了液硫产品的品质，同时降低了H₂S对液硫管线和设备的腐蚀，避免了次生灾害的发生，为硫黄回收装置液硫品质提升提供了新的实施方案。     

羰基硫在氢氧化钠水溶液中的水解动力学

常压下、温度20～50℃,测定了鼓泡反应器中羰基硫(COS)在1.3130～4.4038mol/LNaOH水溶液中的水解速率,获得一级快速不可逆反应的水解速率表达式,其表观活化能为59.63kJ/mol.     

炼焦过程中硫元素迁移规律研究

以华北地区的峰峰低硫肥煤和山西中硫焦煤为原料,利用1 kg热解试验装置进行模拟炼焦试验,并对所得焦炭、煤焦油和煤气产品中硫元素形态和质量进行测定,揭示了炼焦煤中硫元素的迁移规律。结果表明:两种炼焦煤挥发分差别不大,硫元素迁移规律基本相同;炼焦过程中,不但原料煤中硫酸盐硫得以保留,还有其它形态硫经过复杂的热解化合反应生成新的硫酸盐硫;无机硫中的黄铁矿硫和有机硫中的脂肪硫、硫醚、硫醇等在炼焦过程中以H2S形式转移到煤气中,转移效率一般低于50%;原料煤中黄铁矿硫含量越高,H2S的转移率也越高;其他噻吩硫等在炼焦过程中不分解,留在焦炭中。     

中国的硫源和硫肥

分析中国土壤硫量和硫资源结构，介绍硫肥生产现状，指出只有开发和利用潜在硫源，才能解决中国土壤缺硫的问题。     

液硫脱除H2S的新型催化剂—阿基硫

1987年,世界液硫交易量达20Mt。液硫主要来源于弗拉什硫和天然气、油气脱硫回收的硫。最近几年,液硫装运问题成了生产运输者和使用者的顾虑,因为液硫中有无H_2S与安全相关,液硫在撞击和冷却时,H_2S就会释放出来。     

硫肥综述

介绍我国土壤缺硫状况，分析我国缺硫土壤相对较少的原因；估计２０１０年我国农业约需硫４１０万吨；重点说明我国硫磺资源短缺，但硫肥资源相当丰富，农业用硫肥不应该依赖进口。     

MASS TRANSFER AND REACTION IN BUBBLE COLUMN SLURRY REACTOR WITH DRAFT TUBE

Gas-liquid and liquid-solid mass transfer coefficients were obtained in a draft tube bubble column slurry reactor (abbreviated as DTBCSR) from the measurements of gas absorption and ion-exchange, respectively. Oxidation of sulfur dioxide on activated carbon was carried out in the same reactor. The effects of gas flowrates, diameters of draft tube and solid concentrations were investigated. These results were compared with those in a bubble column slurry reactor without draft tube (abbreviated as BCSR). Minimum gas velocities for complete suspension of solid particles in DTBCSR were lower than those in BCSR. Gas-liquid and liquid-solid mass transfer coefficients in DTBCSR were higher than those in BCSR. Both coefficients were almost independent of solid loadings. Reaction rates in DTBCSR were higher than those in BCSR and a stirred slurry reactor (abbreviated as SSR) except for lower gas flow rates and smaller particles.     

超声波作用下柠檬酸盐溶液中SO2的解吸机理

本文从超声波作用特点出发,利用数值计算研究了在超声解吸SO2过程中,超声波的作用机理,从理论上阐明了影响超声解吸SO2的主要因素,并对此进行了实验验证,实验结果与理论分析吻合较好。研究表明,超声场下脱除柠檬酸盐溶液中SO2在理论和实验室规模下是可行的;超声频率、溶液中气体含量以及溶液性质对超声解吸SO2影响较大;给溶液中增加空化气泡核如通入微量惰性气体,SO2解吸效率显著提高;超声频率越低,超声脱除SO2效果越好;给溶液施加适当搅拌,SO2解吸率提高20%～30%;溶液中SO2初始浓度越高,解吸效果越好。     

Modeling the dynamics of tamponade multicomponent gases during retina reattachment surgery

Vitrectomy and pneumatic retinopexy are common surgical procedures used to treat retinal detachment. To reattach the retina, gases are used to inflate the vitreous space allowing the retina to attach by surface tension and buoyancy forces that are superior to the location of the bubble. These procedures require the injection of either a pure tamponade gas, such as C₃F₈ or SF₆, or mixtures of these gases with air. The location of the retinal detachment, the anatomical spread of the retinal defect, and the length of time the defect has persisted, will determine the suggested volume and duration of the gas bubble to allow reattachment. After inflation, the gases are slowly absorbed by the blood allowing the vitreous to be refilled by aqueous. We have developed a model of the mass transfer dynamics of tamponade gases during pneumatic retinopexy or pars plana vitrectomy procedures. The model predicts the expansion and persistence of intraocular gases (C₃F₈, SF₆), oxygen, nitrogen, and carbon dioxide, as well as the intraocular pressure. The model was validated using published literature in rabbits and humans. In addition to correlating the mass transfer dynamics by surface area, permeability, and partial pressure driving forces, the mass transfer dynamics are affected by the percentage of the tamponade gases. Rates were also correlated with the physical properties of the tamponade and blood gases. The model gave accurate predictions in humans. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3651–3662, 2017     

牛顿及非牛顿流体中的气泡生成与对比

采用激光成像结合CCD摄像技术分别对牛顿及非牛顿流体(甘油和羧甲基纤维素钠水溶液)中的气泡生成行为进行了研究,对2种流体气泡生成过程中气泡形状和体积变化进行了比较。分析了非牛顿流体的弹性效应对气泡生成过程气泡形状的影响。实验结果表明,在实验条件范围内,甘油中,气泡生长初期,气泡体积增加较快,到了后期,增加幅度减缓,气速对气泡生长过程气泡体积影响很小;羧甲基纤维素钠(CMC)水溶液中,气泡生长初期,气泡缓慢生长,气速对气泡体积影响很小,到了后期,气泡体积增加幅度变大,气泡体积随着气速的增大而增大。     

Behavior of gas bubbles in a concentric cylindrical airlift column

Using a light transmission optical probe, the effect of superficial gas velocity on bubble properties(bubble size, bubble rising velocity, bubble frequency and local gas holdup) at axial and radial positions was determined in the riser and the downcomer of a concentric cylindrical airlift reactor. The vertical bubble length, the bubble rising velocity and the bubble frequency at axis in the riser increased with increasing superficial gas velocity and the bed height. The radial distribution of the local gas holdup, vertical bubble length and bubble frequency in the riser and the downcomer were found to be non-uniform. The profiles of the local gas holdup, vertical bubble length and bubble rising velocity in the riser were shown as parabolic shapes. The local gas holdup, the vertical bubble length and the bubble frequency in the downcomer changed with superficial gas velocity and the distance from the top of the draft tube.     

微孔曝气最优气泡群的确定方法

综合考虑气泡尺寸、气泡分布、气泡生命周期等对微孔曝气水体DO的影响效果,存在着使曝气效果达到最佳的最优气泡群。本研究提出了微孔曝气最优气泡群的确定方法,并采用最大气泡群常数终值来表征该气泡群。试验结果表明,采用最优气泡群与气泡群常数终值确定的最优曝气器及最优曝气量与清水曝气试验的结果相吻合,同时与采用传统曝气系统性能指标评价的结论也一致。     

电场作用下冷态单气泡形成过程

对氮气泡在电场作用下的形成过程进行了可视化研究。实验观察到电场作用下气泡生长的动态图像;研究表明,电场作用下气泡沿场强方向伸长,随着场强的升高,气泡的脱离长径比增大,脱离体积减小;另外利用Matlab编程从实验中取得实际气泡生长的轮廓线,对气泡界面的电应力计算显示,气泡顶部受到电拉力作用,两侧受电压力作用,从而使气泡产生了沿场强方向的伸长变形。这表明气泡界面受到的电应力是气泡产生变形的主要原因,该结果有助于电场对沸腾传热强化机理的研究。     

Novel phenomenological discrete bubble model of freely bubbling dense gas–solid fluidized beds: Application to two‐dimensional beds

A phenomenological discrete bubble model has been developed for freely bubbling dense gas–solid fluidized beds and validated for a pseudo‐two‐dimensional fluidized bed. In this model, bubbles are treated as distinct elements and their trajectories are tracked by integrating Newton's equation of motion. The effect of bubble–bubble interactions was taken into account via a modification of the bubble velocity. The emulsion phase velocity was obtained as a superposition of the motion induced by individual bubbles, taking into account bubble–bubble interaction. This novel model predicts the bubble size evolution and the pattern of emulsion phase circulation satisfactorily. Moreover, the effects of the superficial gas velocity, bubble–bubble interactions, initial bubble diameter, and the bed aspect ratio have been carefully investigated. The simulation results indicate that bubble–bubble interactions have profound influence on both the bubble and emulsion phase characteristics. Furthermore, this novel model may become a valuable tool in the design and optimization of fluidized‐bed reactors. © 2012 American Institute of Chemical Engineers AIChE J, 2012     

Computational study of bubble coalescence/break-up behaviors and bubble size distribution in a 3-D pressurized bubbling gas-solid fluidized bed of Geldart A particles

A computational study was carried out on bubble dynamic behaviors and bubble size distributions in a pressurized lab-scale gas-solid fluidized bed of Geldart A particles. High-resolution 3-D numerical simulations were performed using the two-fluid model based on the kinetic theory of granular flow. A fine-grid, which is in the range of 3–4 particle diameters, was utilized in order to capture bubble structures explicitly without breaking down the continuum assumption for the solid phase. A novel bubble tracking scheme was developed in combination with a 3-D detection and tracking algorithm (MS3DATA) and applied to detect the bubble statistics, such as bubble size, location in each time frame and relative position between two adjacent time frames, from numerical simulations. The spatial coordinates and corresponding void fraction data were sampled at 100 Hz for data analyzing. The bubble coalescence/break-up frequencies and the daughter bubble size distribution were evaluated by using the new bubble tracking algorithm. The results showed that the bubble size distributed non-uniformly over cross-sections in the bed. The equilibrium bubble diameter due to bubble break-up and coalescence dynamics can be obtained, and the bubble rise velocity follows Davidson’s correlation closely. Good agreements were obtained between the computed results and that predicted by using the bubble break-up model proposed in our previous work. The computational bubble tracking method showed the potential of analyzing bubble motions and the coalescence and break-up characteristics based on time series data sets of void fraction maps obtained numerically and experimentally.     

柴油液滴内空化气泡的破碎研究(英文)

A modified mathematical model is used to study the effects of various forces on the stability of cavitation bubbles within a diesel droplet. The principal finding of the work is that viscous forces of fluids stabilize the cavitation bubble, while inertial force destabilizes the cavitation bubble. The droplet viscosity plays a dominant role on the stability of cavitation bubbles compared with that of air and bubble. Bubble–droplet radius ratio is a key factor to control the bubble stability, especially in the high radius ratio range. Internal hydrodynamic and surface tension forces are found to stabilize the cavitation bubble, while bubble stability has little relationship with the external hydrodynamic force. Inertia makes bubble breakup easily, however, the breakup time is only slightly changed when bubble growth speed reaches a certain value (50 m·s?1). In contrast, viscous force makes bubble hard to break. With the increasing initial bubble–droplet radius ratio, the bubble growth rate increases, the bubble breakup radius decreases, and the bubble breakup time becomes shorter.