Simulation Research on Coal-Water Slurry Gasification of Oil-Based Drill Cuttings Based on Fluent

In this paper,based on Fluent software,a five-nozzle gasifier reactor was established to simulate the gasification process of oil-based drill cuttings coal-water slurry.The influence of concentration and oxygen/carbon atomic ratio on the gasification process of oil-based drill cuttings coal-water slurry was investigated.The results show that when the oxygen flow is constant,the outlet temperature of gasifier decreases,the content of effective gas increases,and the carbon conversion rate decreases with the increase of concentration;When the ratio of oxygen to carbon atoms is constant,the effective gas content rises and the temperature rises with the increase of the concentration,and the carbon conversion rate reaches the maximum value when the concentration of oil-based drill cuttings coal-water slurry is 65%;When the concentration is constant,the effective gas content decreases and the outlet temperature rises with the increase of the oxygen/carbon atom ratio,and the carbon conversion rate reaches 99.80%when the oxygen/carbon atom ratio is 1.03.It shows that this method can effectively decompose the organic matter in oilbased drill cuttings and realize the efficient and cooperative treatment of oil-based drill cuttings.

Effect of the benzene ring of the dispersant on the rheological characteristics of coal-water slurry:Experiments and theoretical calculations

In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PDPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to investigate the pulping properties and microscopic mechanism of the LCWS samples prepared using the two agents,so as to explore the influence of benzene ring on the performance of dispersant.The results of the LCWS preparation experiments revealed that the pulp-forming performance of PDPE exceeded that of PLE.When LCWS concentration is 62%,64%,and 66%,the apparent viscosity corresponding to PDPE is 247.80,504.17,and 653.10 mPa·s,and the apparent viscosity corresponding to PLE is 548.10,1470.61,and 1549.98 mPa·s,respectively.The C_(1000)(When the apparent viscosity is 1000 mPa·s,the corresponding concentration of LCWS is defined as C_(1000))values of PDPE and PLE are 67.60%and 62.95%,respectively.In addition to the van der Waals forces and hydrogen bonds between the PDPE and/or PLE molecules and coal,the benzene rings of PDPE presentπ-πstacking effect with the aromatic rings of coal.That could facilitate and strengthen the adsorption of PDPE on coal,which would be conducive to further improving the dispersion of coal particles.The two dispersants have no significant difference in effect on the pyrolysis of LCWS.The simulation results indicated that the times for PDPE and PLE molecules to reach flat adsorption state on coal are approximately 290 and 565 ps,respectively.The self-diffusion coefficient(D)of the PDPE and PLE on coal is 3.16 x 10^(-6)and6.57×10^(-6)m~2/s,respectively,and their interaction energies with coal are 785.71 and 648.60 kcal/mol,respectively.The results of the simulation calculations demonstrated that PDPE adsorbed on coal easier than PLE,and its binding is more stable than that of PLE owing to theπ-πstacking effect,which is conducive to uniform dispersion of coal in solution.The simulation results confirmed the experimental results.

Effect of the high-power electromagnetic pulses on the reactivity of the coal-water slurry in hot environment

An effect of the high-power electromagnetic pulses onto the droplet of coal-water slurry inside the furnace was investigated.In contrary to the previously investigated laser-induced fuel atomization that occurs at the room temperature,the pre-heated(to 400 K)slurry becomes dry enough to prevent the explosion-like steam formation.Thus,fuel does not atomize and the ignition does not accelerate.Furthermore,the absorption of several laser pulses leads to evident sintering of irradiated surface with following increase of the ignition delay time for up to 24%.Variation of the pulse energy in range 48-118 mJ(corresponding intensity up to 2.4 J·cm^-2)leads to certain variation of the increase of ignition delay.The strong pulsed overheating of the coal water slurry which does not initiate the fine atomization of the fuel generally makes its ignition longer.

Combustion and Sulfur-fixing Performance of Pulping Black Liquor Coal-water Slurry

The effects of adding pulping black liquor and other additives to coal-water slurry(CWS) on the sulfur-fixing performance of the resultant mixture(pulping black liquor coal-water slurry) were evaluated. The experimental results demonstrated that the ash content of the black liquor coalwater slurry decreased as the addition of pulping black liquor in the mixture increased. Nevertheless, the addition amount should be appropriately selected to ensure that the black liquor coal-water slurry had a moderate calorific value. Addition of black liquor improved the combustion performance of CWS by lowering the ignition point and stabilizing the combustion process; moreover, the sulfur-fixation ratio after combustion increased by 12 to 16 percentage points than that of CWS, and the content of high-melting-point salt in the ash from CWS after adding black liquor was low. The sulfur-fixing ratio of CWS after adding a sulfur-fixing agent was effectively increased by 25 to 30 percenatge points, but with compromise of the fluidity and stability of the CWS; thus, the addition amount of a sulfur-fixing agent should be optimized.

Improving slurryability, rheology,and stability of slurry fuel from blending petroleum coke with lignite

Petroleum coke and lignite are two important fossil fuels that have not been widely used in China. Petroleum coke-lignite slurry （PCLS）, a mixture of petro- leum coke, lignite, water, and additives, efficiently utilizes the two materials. In this study, we investigate the effects of the proportion （7） of petroleum coke on slurryability, rheo- logical behavior, stability, and increasing temperature characteristics of PCLSs. The results show that the fixed- viscosity solid concentration （COo） increases with increasing 7. The ~Oo of lignite-water slurry （LWS, ~ = 0） is 46.7 %, compared to 71.3 % for the petroleum coke-water slurry （PCWS, c~ --- i00 %）, while that of PCLS is in between the two values. The rheological behavior of PCLS perfectly fits the power-law model. The PCWS acts as a dilatant fluid. As decreases, the slurry behaves first as an approximate Newtonian fluid, and then turns into a pseudo-plastic fluid that exhibits shear-thinning behavior. With increasing ct, the rigid sedimentation and water separation ratio （WSR） increase, indicating a decrease in the stability of PCLS. When α is 60-70 %, the result is a high-quality slurry fuel for industrial applications, which has high slurryability （ω0 = 57-60 %）, good stability （WSR 〈 2 %）, and superior pseudo-plastic behavior （n = 0.9）.

Ice Slurry Formation in a Cocurrent Liquid-Liquid Flow

为冰泥浆生产的一种新技术被探索。多重小水滴被单个嘴的 atomizer 在另一不能混合的 chilled 液体形成并且由直接接触热转移在使流体化的床上结冰。实验被进行调查做系统的冰水晶的动态行为。结果证明冰晶体能与下面的起始的温度的传播冷却剂在垂直的床上连续地并且稳定地被生产 ? 5 掳 C。冰晶体的尺寸分发显得不一致，但是以更低的油流动率更类似、更一致。吝啬的冰水晶尺寸由喷气速度和油流动率严重承担。它与减少减少油流动率，和活动范围在在大约 16.5 m 路 s 的中间的喷气速度的最大值 ? 1。冰水晶尺寸也是仔细与现象有关联合落下，它能被减少流动率或降低搬运人油的温度更加减轻。然而，液体液体粉碎成原子的优化是一条更有效的途径生产需要的尺寸的好冰晶体。

Study on Characteristics of Different Types of Nozzles for Coal-Water Slurry Atomization

Three types of nozzles: a low-pressure multistage nozzle, an effervescent nozzle and a newly developed internal- mixing air-blast nozzle, for atomization of Coal-Water Slurry (CWS) were investigated. Influence of CWS properties including surface tension and apparent viscosity on atomization was studied. Comparisons among the nozzles were carried out in terms of spray droplet mean diameter and fuel output. Versatility of each nozzle was investigated and atomization mechanism of each nozzle was analyzed as well. The results showed that the newly developed internal- mixing air-blast nozzle has high fuel output and small mean droplet size in the spray, but the multistage nozzle has high versatility for handling of low quality CWS.

Research on the Atomization Characteristics of UCMCWS──A Novel Diesel Oil Substitute

Ultra-Clean Micronized Coal Water Slurry (UCMCWS ) as a form or coal-based fuel can be used in place of oil in diesel engine, gas turbine and clean combustion. In laboratory UCMCWS has been made from ultra-clean coal with ash less than 0. 8%, with concentration of UCMCWS less than 55%, and with viscosity less than 600 mPa. s. A test rig of atomization with diesel oil nozzle has been made. A preliminary conclusion is that UCMCWS can be atomized as good as diesel oil in the working condition of diesel engine.

CORRECTION OF WALL SLIP EFFECTS AND RHEOLOGICAL MEASUREMENT OF HIGH CONCENTRATED COAL WATER SLURRY

Coal-water slurry, a ncw liquid fuel, began to appcar during the world-wide petroleum crisis in the seventies of this century. Its applications to substitute petroleum drew great attention on the investigations of its preparation, combustion and transportation, etc. The rheological behavior is an important quality index for the fuel. However, the conventional viscosimeters designed for true fluids are not suited to the high concentrated slurry due to the complicated rheological bchavior. A special viscosimeter of tube type was rcpresented, which was designed and set up by the authors for the measurement of the theology of high concentrated coal-water slurry and experiments were conducted with two kinds of slurries from P. R. China. In consideration of the wall sliD effects the correction of the experimental data were made.

悬浮液进样原子吸收光谱分析中样品的粒径效应

研究了悬浮液进样 FAAS和悬浮液进样 GFAAS中样品粒径效应。实验表明 ,悬浮液颗粒粒径 <30 μm能满足石墨炉原子化测定需要 ,而火焰原子化要求在粒径≤ 5 μm的前提下 ,再根据待测元素的性质选择合适的火焰类型 ,方能达到较满意的测定效果。

悬浮液进样流动注射在线微波消解-冷蒸气原子荧光光谱法测定生物和环境样品中的汞

建立了悬浮液进样流动注射在线微波消解 冷蒸气原子荧光光谱法测定生物和环境样品中Hg的方 法。样品分散在50%(V/V)王水中,通过磁力搅拌保证样品溶液的均一性与稳定性。方法的检出限为 0.06μg/L。方法简单快速,灵敏度高,样品损失少,而且没有样品交叉污染。应用此方法测定了5种标准参 考物质以及5个实际样品中的Hg含量,并与传统的高压焖罐强酸消解方法进行了比较,两种方法所得结果 一致,标准参考物质的测定值与标准值很好地吻合。

悬浮液进样石墨炉原子吸收光谱分析进展

悬浮液石墨炉原子吸收光谱分析结合了固体和液体进样方式的显著优势,是一种相对成熟的技术,并已作为常规分析方法广泛应用于有机和无机复杂基体中微、痕量金属元素的分析测定。文章结合最近10年来所取得的新进展进行综述,着重介绍和评论了悬浮液的制备(介质、稳定剂、质量体积比、粒径、均匀化体系)、基体改进剂、背景校正、方法校正及其分析的精密度等,并对悬浮液石墨炉原子吸收光谱分析的发展趋势进行了展望。全文共引用国内外文献80篇。

烟道喷浆脱除烟气中二氧化硫的试验研究

在长3.5 m、断面积为150 mm×150 mm的立式反应器中进行了烟道喷石灰浆和电石渣浆脱除烟气中SO_2的模拟试验,得出了出口温距、钙硫摩尔比、雾化气液比、SO_2入口浓度、烟气入口温度和气体停留时间对脱硫效率的影响规律。试验还表明,当ΔT=18℃,Ca/S=1.5时,系统脱硫效率可达65%。同时,建立了反应预测模型η=1-[T_i—T_(as))/(T_0—T_(as))]-αR/β+R,其中参数α和β采用共轭梯度法估值,模型预测值与实测值的平均相对偏差低于7%。

悬浮液进样平台石墨炉原子吸收光谱法测定生物样品中痕量铅

本文采用超声粉碎生物样品悬浮液进样平台石墨炉原子吸收光谱法测定痕量铅，使用ＮＨ４Ｈ２ＰＯ４为基体改进剂消除共存元素干扰。方法简便、快速，分析结果准确可靠。

低压旋流雾化喷嘴的雾化性能

石灰浆液雾化喷嘴是烟气喷雾干燥脱硫系统的关键设备。利用Win212-2型激光粒度分析仪,对不同结构参数的低浓度石灰浆旋流雾化喷嘴的低压雾化性能进行了实验研究,得出了喷嘴结构参数对喷嘴雾化性能的影响规律和石灰浆低压旋流雾化喷嘴的最优化结构参数。优化后的喷嘴结构参数为:旋流片槽数为4,旋流片槽张角6°,旋流室收缩角90°,D/d=4.4～6.4,D/b=6～8,L/b=3.3～4.0。该喷嘴在0.8MPa的低压下,雾化粒度可达到100μm以下,雾化角为70°左右,具有良好的雾化性能,比普通喷嘴的雾化性能有较大提高。

脱硫溶液性质对空腔雾化放电特性的影响

为了寻求治理SO2、NOx等气体污染物的新方法,利用高压电场的场致发射原理,采用高压静电雾化技术将不同液体雾化,并研究了其相关的放电性能。通过对实验结果的分析,总结了不同电极形式及液体性质对电晕放电的影响。结果表明:在电极直径和放电电压均相同的情况下,空腔-线式放电结构的雾化效果优于空腔-板式结构;减小雾化电极的空腔半径能获得更好的雾化效果;溶液中的活性离子对液滴中水分子间氢键的破坏作用有利于溶液雾化;浆液中的固体颗粒数量与浆液的表面张力及粘度成正相关关系,且浆液中的固体颗粒对溶液分子的聚合作用远大于溶液中的离子对氢键的破坏作用,浆液中颗粒数量增加将减弱液滴的放电强度及雾化效果。

悬浮液氢化物发生原子荧光光谱法测定化探样品中痕量铋

本文提出了一种把悬浮液技术与氢化物发生法相结合原子荧光光谱法测定化探样品中痕量铋的分析方法。试验了悬浮液粒度、酸介质、悬浮液浓度等因素对铋氢化物发生效率的影响。采用水溶液标准校正，方法简便，结果准确可靠。

水煤浆多级喷嘴的雾化和流动特性

研究了一种多级气动喷嘴对水煤浆燃料的喷雾特性的影响 .采用实验方法研究了水煤浆性质、喷嘴操作工况和喷嘴几何结构对射流雾化细度的影响 .对喷嘴出口附近的两相流场进行了数值计算 ,并针对相关结果进行了分析 .研究结果证明 ,该喷嘴对水煤浆燃料有很好的雾化性能 。

悬浮液进样自吸扣背景石墨炉原子吸收光谱法测定高纯氧化铝中铜、铁和钠含量

采用悬浮液-自吸扣背景石墨炉原子吸收法测定了高纯氧化铝中痕量元素铜、铁、钠含量。实验对灰化温度、原子化温度和自吸扣背景灯电流等石墨炉原子吸收工作条件等进行了优化,确定了最佳测定条件。样品测试采用标准水溶液进行校正,方法准确性采用氧化铝AKP-30在高温高压和浓硫酸密闭条件下溶解样品进样分析测定结果与文献报道的其他测定方法结果进行了对比。研究表明本方法简单,结果可靠,适用于氧化铝中痕量元素的快速测定。校正曲线的线性相关性大于0.9990,方法对铜、铁、钠的检出限分别为0.66,2.5,0.13ng·g-1,相对标准偏差小于5.2%。