高温煤气脱硫剂的开发研究

本文对高温煤气脱硫剂的制备及脱硫工艺条件做了研究，并对脱硫剂进行了十五个周期的脱硫再生循环试验。结果表明,制备的脱硫剂在600～620℃、常压及空速为1000h-1的条件下脱硫，脱硫剂强度及硫容没有出现明显下降，也没有出现脱硫剂的粉化现象。     

高温煤气脱硫剂再生行为气氛效应的研究进展

脱硫剂再生过程是高温煤气脱硫工业化应用必备的关键环节之一。本文重点综述了含氧气氛、水气氛、水氧混合气氛和二氧化硫气氛中高温煤气脱硫剂的再生行为。以硫资源化回收作为高温煤气脱硫剂再生的目标,分析了不同再生气氛以及不同再生操作条件对高温煤气脱硫剂再生行为的影响。最后对今后高温煤气脱硫剂的再生研究提出了几点建议。     

高温煤气铁系脱硫剂的研究

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 .     

高温煤气脱硫剂再生性能研究进展

金属复合型脱硫剂已经成为高温煤气脱硫剂的研究重点,脱硫剂不仅要求具有良好的硫化能力,还必须易于再生,以达到多次循环使用及降低生产成本的目的。介绍了中高温煤气脱硫剂的再生性能的研究概况,包括:铁和锌系列脱硫剂、钙和铈系列脱硫剂、铜和锰系列脱硫剂。大量实验研究表明,脱硫剂的种类和再生工艺与其再生后的脱硫特性密切相关,再生结果是脱硫剂能否工业化应用的关键环节之一,在考察脱硫剂硫化特性的同时,必须注重脱硫剂再生特性的研究。     

热煤气一体化净化工艺中的脱硫反应特征

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.     

新型长寿命热煤气脱硫剂的研制

介绍了“九五”科技攻关项目“联合循环发电关键技术－高温煤气脱硫研制及脱硫再生工艺研究开发”专题中,关于研制新型长寿命脱硫的最新结果。经大量的配方设计及试验,成功筛选出G－201及G－202两种脱硫剂。其中G－201脱硫剂在工艺放大的试验装置上首次成功地通过1500h真实热煤气脱硫长寿命考核试验。经过检查,考核试验后的脱硫剂无粉化和烧结现象,并保持足够的机械强度、实测硫容仍保持21％,守好如初。     

高温煤气脱硫剂铁酸锌的性能及再生研究

以共沉淀法制备的铁酸锌作为脱硫剂的活性组分制备了一种新型的高温煤气脱硫剂.对不同工艺条件下脱硫剂脱硫活性、再生条件及使用寿命进行了研究.结果表明,铁酸锌脱硫剂的脱硫效果显著,较高的温度下可得到高的硫容量;高的氧气含量可加快其再生速率,但硫容量会有所降低.     

粉煤灰作为高温煤气脱硫剂载体的可行性研究

基于XRD、SEM、激光粒度分析仪和成分分析等不同测试方法,比较了不同大小的粉煤灰颗粒的物化性质和微观形貌特征。以不同颗粒大小的粉煤灰为载体,制备了一系列铁铈氧化物高温煤气脱硫剂,以此研究粉煤灰作为高温煤气脱硫剂载体的可行性。在600℃的硫化实验表明,粉煤灰作为铁基高温煤气脱硫剂的载体,不仅能有效提高脱硫剂的脱硫精度和其硫化再生后的机械强度,且粉煤灰自身也有一定的脱硫作用。     

锰系可再生高温脱硫剂的制备及其性能测试

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。     

高温煤气脱硫剂及再生特性研究

高温煤气净化是实现IGCC过程的关键环节，系统地介绍了国内外钙、锌、铜的锰系高温脱硫剂近年来的研究结果，同时结合脱硫剂再生的研究，分析了各种脱硫剂在高温脱硫过程中可能遇到的问题，探讨了各种脱硫剂的再生方法以及相应的尾气处理方案，最后对我国今后高温煤气脱硫剂研究开发提出了几点建议。     

高温煤气金属脱硫剂的研究进展

煤的清洁转化利用符合中国的能源结构,高温煤气脱硫是提高能源利用率的关键技术。本文综述了单一金属氧化物和复合金属氧化物干法脱除H2S的研究进展,对比分析了单一金属氧化物在脱硫效率、使用温度和再生方面的优缺点,指出由于单一金属氧化物脱硫剂不能满足实际生产需要,因此兼有单一金属氧化物优点的复合金属脱硫剂成为未来研究方向。同时,论述了复合金属脱硫剂的制备原则、脱硫效率及再生等方面的研究状况。在此基础上,重点对铁酸锌和钛酸锌两种具有代表性的复合脱硫剂及其他复合金属脱硫剂进行了介绍。     

New development of zinc-based sorbents for hot gas desulfurization

This paper introduced two new zinc-based sorbents for hot gas desulfurization, G-201 and G-202. Evaluation tests proved that both G-201 and G-202 sorbents had good performance in desulfurization. They could reduce H₂S concentration from about 10 g/m³ in coal gas to less than 20 mg/m³. In addition, the sulfur capacity of both sorbents increased with temperature rising. No decrease in sulfur capacity of G-201 occurred during 20-desulfurization/regeneration cycle tests, whose calculated value was 19.43–24.23 g/100 g sorbent. G-201 sorbent passed a 1500 h real hot gas desulfurization test in a fixed-bed PDU. No occurence of striping, attrition and sintering on the surface of used sorbents was found after the long-time test. The reactivity was stable and the sulfur capacity is 21.19 g/100 g sorbent after the 1500 h test.     

硫化条件对氧化铈高温煤气脱硫剂的影响

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。     

Experimental and model investigation on the mass balance of a dry circulating fluidized bed for flue gas desulfurization system

A moderate temperature dry circulating fluidized bed flue gas desulfurization (CFB-FGD) process was developed using rapidly hydrated sorbent. This technique has the advantages of low cost, no water consumption, and a valuable dry product CaSO₄. To keep the system operation stable, a mass balance model, based on cell model considering flow state, particle abrasion, particle residence time, particle segregation and desulfurization processes, was built to predict the system state and optimize the operating condition. Experimental studies were conducted on a pilot-scale CFB-FGD system with rapidly hydrated sorbent made from CFB circulating ash and lime (circulating ash sorbent) or coal fly ash and lime (coal fly ash sorbent). Calculated results were compared with experimental results and the relative error was less than 10%. The results indicated that feed sorbent mass, feed sorbent size, superficial gas velocity, particle abrasion coefficient and cyclone efficiency had significant influence on the mass balance of CFB system. The circulating ash sorbent was better than the coal fly ash sorbent, for providing higher desulfurization efficiency and being better for the CFB-FGD system to achieve mass balance.     

微波固相法制备铁酸锌脱硫剂的硫化动力学

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。     

Removal of SO2 in Semi‐Dry Flue Gas Desulfurization Process with a Powder‐Particle Spouted Bed

Semi‐dry flue gas desulfurization was investigated with several kinds of SO₂ sorbents, such as slaked lime, limestone, Mg(OH)₂ and concrete pile sludge, in a powder‐particle spouted bed. Slurry droplets including sorbent fine particles were fed to a spouted bed of coarse inert particles spouted with hot gas containing SO₂. SO₂ removal efficiency was strongly affected by the approach to saturation temperature, Ca/S molar ratio and particle size of sorbent. Slaked lime showed the highest desulfurization efficiency. In this process, despite very short gas residence time, more than 90% SO₂ removal was easily achieved by choosing appropriate conditions.     

CO2对石灰石脱硫剂的活化作用

在间歇式鼓泡反应器的烟气脱硫实验装置中,研究了CO2气体活化处理对石灰石脱硫剂浆液烟气脱硫效率的影响. 依据脱硫过程中石灰石脱硫剂浆液pH值随脱硫反应时间的变化规律,初步分析了CO2对石灰石脱硫剂的活化作用及活化后石灰石脱硫剂的烟气脱硫过程机理. 结果表明,CO2气体的活化处理促进了石灰石在水溶液中的溶解,进而改善了石灰石脱硫剂浆液的烟气脱硫反应活性,使处理后的石灰石脱硫剂浆液的烟气脱硫效率和脱硫剂的利用率提高. 基于流化床反应器连续过程的实验结果,证实了CO2对石灰石脱硫剂的活化作用. 为提高石灰石在烟气脱硫中的反应活性提供了一种新的工艺,可用于烟气脱硫中对石灰石脱硫剂浆液的活化.     

Sulfidation and regeneration of iron-based sorbents supported on activated-chars prepared by pressurized impregnation for coke oven gas desulfurization

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.