共查询到19条相似文献,搜索用时 250 毫秒
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高温煤气铁系脱硫剂的研究 总被引:6,自引:5,他引:6
高温煤气脱硫净化是目前先进洁净煤利用技术之一 ,但是以前高温煤气脱硫剂在多次硫化再生循环过程中出现粉化 ,妨碍脱硫剂进一步使用 .本研究选择钢厂赤泥作为脱硫剂原料 ,添加不同活性组分和防粉化结构助剂 ,制备了氧化铁基高温煤气脱硫剂 .经过 1 0次硫化 /再生循环实验 .结果表明 :1 0次循环累计 1 96.98% ,再生后脱硫活性不发生变化 ,具有较高和较稳定的脱硫活性 .再生后脱硫剂的机械强度高于新鲜样品 ,在使用过程中没有出现粉化现象 ,这为氧化铁基高温煤气脱硫剂的工业化研究提供了可靠的依据 . 相似文献
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氧化铈是一种新型的高温煤气脱硫剂,它的主要优点是再生过程中能产生单质硫。本文采用工业硝酸铈Ce(NO3)3.6H2O为原料制取CeO2,用干混法制备CeO2高温煤气脱硫剂。在固定床反应器中考察不同空速、不同硫化温度以及水气氛对脱硫剂脱硫效率的影响。结果表明:硫化温度800℃,空速1 500 h-1脱硫剂的脱硫效率较高;水气氛的存在,抑制了脱硫剂的还原与硫化,使得脱硫剂的脱硫效率下降。 相似文献
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热煤气一体化净化工艺中的脱硫反应特征 总被引:1,自引:0,他引:1
利用固定床反应器考察了高温煤气脱硫除尘一体化净化工艺中沉积粉尘对高温煤气脱硫剂脱硫性能的影响.结果表明,表面沉积粉尘对脱硫剂初次硫化行为有明显的影响,且与脱硫剂的组成和结构有关.利用钢厂赤泥制备的脱硫剂,含有多种惰性杂质,且具有较大的孔径结构,易于和粗煤气中的粉尘作用,造成脱硫剂硫容的减小.硫化气氛中,H2O的存在造成脱硫剂硫容和脱硫效率的降低,但不会影响因表面沉积粉尘造成的脱硫剂硫容的减小.多次硫化-再生循环实验表明,硫化-再生循环过程有助于减小表面沉积粉尘对脱硫剂脱硫行为的影响.经历一定次数的硫化-再生循环后,粉尘对脱硫剂脱硫行为的影响逐渐消失. 相似文献
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通过微波与常规固相法制备了铁酸锌高温煤气脱硫剂,使用X射线衍射(XRD)、氮吸附、扫描电子显微镜(SEM)以及X射线光电子能谱(XPS)对两种不同焙烧方式制备的脱硫剂的物相组成、织构形貌和表面元素进行了表征。数据显示微波焙烧制备的脱硫剂具有孔隙结构丰富、表面金属元素含量高、结合能低等优点。使用热天平对铁酸锌脱硫剂硫化行为进行了研究,根据等效粒子模型计算了两种脱硫剂与硫化氢气体反应的动力学参数,得到了硫化反应动力学方程,并在固定床上对其煤气脱硫性能进行了考察。结果表明硫化过程分为化学反应控制区和颗粒内扩散控制区。微波焙烧制备脱硫剂的化学反应活化能和颗粒内扩散活化能较低,说明其在硫化氢气体脱除上具有更高的活性。在模拟煤气气氛下,相比常规焙烧方法制备的脱硫剂,微波制备的脱硫剂的脱硫性能显著提高,具有更高的硫容和更长的精脱硫时间。 相似文献
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煤气的高温脱硫净化是 IGCC 和 DRI 生产的瓶颈,直接影响整个过程的热效率。在50℃、pH值约为9的条件下采用硝酸锰、硝酸铝混合溶液与氨水进行共沉淀,制备了锰含量不同的脱硫剂,在固定床反应器中考察了脱硫剂的硫化及再生性能,并利用XRD、SEM、BET等手段表征了脱硫剂在硫化/再生过程中的物相和结构变化。共沉淀法制备的脱硫剂Mn/Al分散性好,在850℃高温下进行脱硫反应可以定量快速进行。脱硫硫容与脱硫剂锰含量呈正比,Mn-S/Mn-O交换原子比在0.90~0.95之间,改变空速和进口H2S含量并不改变脱硫硫容。采用O2浓度为3%的稀释空气在850℃下再生,再生后的硫容稳定,说明所制备的脱硫剂可用于高温可再生脱硫。 相似文献
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Removal of sulfur at high temperatures using iron-based sorbents supported on fine coal ash 总被引:3,自引:0,他引:3
This paper deals with the simultaneous removal of H2S and COS in the temperature range of 400-650 °C at 1 bar by using iron-based sorbents. The iron-based sorbents were prepared using iron oxide and cerium oxide with coal fine ash as the support. Simulated coal gas was used in the sulfidation experiments and 5% O2 in N2 gas was used for regeneration of sorbents. Both sulfidation and regeneration experiments have been carried out using a fixed-bed quartz reactor. The product gases were analyzed using a GC equipped with a TCD and a FPD. The results demonstrated that both H2S and COS can be effectively reduced using the iron-based sorbents supported on fine coal ash. XRD analysis shows that Fe1−xS phase has formed during sulfidation indicating a high sulfur capacity of the sorbent. The mechanism of the removal of COS simultaneously with H2S is also discussed. 相似文献
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Jianglong YU Liping CHANG Fan LI Kechang XIE 《Frontiers of Chemical Engineering in China》2010,4(4):529-535
In poly-generation and integrated gasification-combined cycle (IGCC) systems for clean energy conversion, it is essential
to remove impurities such as sulfur species from hot coal gases prior to entering the subsequent units. This paper provides
a comprehensive review on previous studies on high temperature removal of hydrogen sulfide from high temperature coal gases
using iron-based sorbents. A two-step desulphurization process for hot coal gas cleanup is highlighted, which is integrated
with direct production of elemental sulfur during regeneration of iron-based sorbents in the primary desulphurization step.
Different kinetic modeling approaches for sulfidation and regeneration were compared. Limited research on activated carbon
supported sorbents was also briefly summarized. 相似文献
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Jinxiao Dou Yongqi Zhao Arash Tahmasebi Jianglong Yu 《Korean Journal of Chemical Engineering》2016,33(10):2849-2857
The sulfidation and regeneration properties of lignite char-supported iron-based sorbent for coke oven gas (COG) desulfurization prepared by mechanical stirring (MS), ultrasonic assisted impregnation (UAI), and high pressure impregnation (HPI) were investigated in a fixed-bed reactor. During desulfurization, the effects of process parameters on sulfidation properties were studied systematically. The physical and chemical properties of the sorbents were analyzed by X-ray diffraction (XRD), scanning electron microscope coupled with energy dispersive spectroscopy (SEM-EDS), Fourier transform infrared (FTIR) and BET surface area analysis. The results of desulfurization experiments showed that high pressure impregnation (HPI) enhanced the sulfidation properties of the sorbents at the breakthrough time for char-supported iron sorbents. HPI method also increased the surface area and pore volume of sorbents. Sulfur capacity of sorbents was enhanced with increasing sulfidation temperatures and reached its maximum value at 400 °C. It was observed that the presence of steam in coke oven gas can inhibit the desulfurization performance of sorbent. SO2 regeneration of sorbent resulted in formation of elemental sulfur. HPIF10 sorbent showed good stability during sulfide-regeneration cycles without changing its performance significantly. 相似文献
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针对洗煤灰分常规测定方法时间长,不能及时反映洗煤质量的问题,采用了XL-6338A快速煤质分析仪测定洗煤灰分。分析了该仪器测定灰分时影响其准确性的因素。通过各因素下该仪器测定数据与重量法测定数据的多次对比,得出把洗煤试样粒度控制在≤3mm、水分控制在≤10%、堆密度控制在每桶(2.53±0.05)kg,可得到较准确的灰分测定数据。 相似文献
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A Study on the Regenerable Co and Ni-Based Sorbents to Remove Hydrogen Sulfide at Middle Temperature
Jung Je Park Suk Yong Jung Chang Geun Park Soo Chool Lee Jae Chang Kim 《Topics in Catalysis》2010,53(7-10):635-640
To remove hydrogen sulfide from hot coal gases at middle temperature, the various sorbents were prepared by precipitation or co-precipitation method. The cobalt and nickel-based sorbents promoted with alumina showed good regeneration properties during multiple cycles. The roles of each component in the sulfidation and regeneration were discussed with the results from XRD and TPD. 相似文献
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Bongjin Jung 《Korean Journal of Chemical Engineering》1996,13(6):633-639
The electrical resistance and compressive strength were measured to gain a better understanding of the sintering characteristics
of low-rank coal ashes involved in deposit formation in combustion systems. Low-rank coal ashes were prepared by the standard
ASTM ashing procedures at 750°C and then separated into three different particle size fractions. The sinter point determined
by the electrical resistance method decreased with decreasing particle size at three different particle size fractions of
each coal ash. The compressive strength lest was made as a function of temperature in the range 750–950°C. At a given sintering
temperature, strength of the sintered ash was inversely proportional to particle size. For any given particle size of each
coal ash, the strength increased with increasing sintering temperature. X-ray diffraction of the sintered coal ashes showed
that, as sintering temperature increased, there was an inverse relationship between sinter strength and the amount of anhydrite
in the sintered ash, and a direct relationship between strength and the amount of hauyne. 相似文献
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Qin ZhangYingzhong Tian Yueqin QiuJianxin Cao Tiancun Xiao 《Fuel Processing Technology》2011,92(3):692-698
Tonnage of coal samples were collected from Kaitai Coal field, Puan County, Guizhou Province and sieved into different particle size catalogs. The analysis of the overall coal suggested that the coal has low ash but high sulfur content of 3.17 wt.% with medium to high volatile content. The heating value of the coal is 31.668 mJ/kg.The coal sample with different particle size ranges were tested for float-sink using gravity separation method, in which ZnCl2 solutions with different density are used. It is showed that decreasing sulfur to 2.12 wt.% can give coal yield of 94.55%, suggesting that the coal's floatability is good with sulfur. The coal yield is only 85.4% when reducing sulfur to 1.5 wt.%, and 76.7% when sulfur is decreased to 1.2% through the ZnCl2 float-sink process. The δ ± 0.1 is 20.55, which is in the 20.1-30 range, suggest that Kaitai coal is difficult to float-sink for depyritisation.Characterization of the floated coal at different sizes showed that the organic sulfur may mainly be present in the small size, the pyrite sulfur is mainly present in the coal with bigger particle size, which can be easily removed through float-sink process. The ash in the small particle sized coal is mainly from kaolinite and quartz, while the pyrite is the main ash contributor to the coal with big size. 相似文献