Effect and influence factors of sulfur removal in coal with fungus

The influence of coal desulfurization by fungus was experimentally studied. The results suggest that fungus can effectively remove inorganic and organic sulfur in coal, and main influences of desulfurization by fungus of pH value, temperature, coal slurry concentration and coal granularity were studied by orthodox experiment and the optimal experimental conditions are as follows: pH value 6, temperature 45 °C, coal slurry concentration 10% and coal granularity 100 μm. Under above conditions, fungus can remove up to 44.96% total sulfur and 54.87% inorganic sulfur within two days, and their desulfurization rates will increase along with time. Compared with sulfolobas, desulphurization by fungus is steady and more effective, and has advantage of high speed. Foundation item: Project(2002AA649220) supported by Hi-tech Research and Development Programe; project(1667) supported by the Postdoctoral Science Foundation of Central South University     

Main influence factors on desulfurization of coal by sulfolobas

1　INTRODUCTIONHighsulfurcoalwhichletsoutpoisonousandharm fulgassuchassulfurdioxideintheprocessofcoalcom bustion ,isamainfactortoform greatareaacidrainandoccupiesonethirdreservesoftotalcoalinChina .Manhaspaidmuchattentiontoseriousenvironmentpollutionmadebysulfurincoalandsearchedforaspeed ,low costandeffectivetechnologyofdesulfurizationwhichhasbecomeasignificantenvironmentprotectiontasknowadays[1] .Coaldesulfurizationcanbesortedintofore burning ,aflame burningandafter burningbyburningproce…     

Main influence factors on desulfurization of coal by sulfolobas

By orthodox experiment, the main influence factors of desulfurization by sul folobas of pH value, temperature, coal slurry concentration and coal granularity are studied in detail and the optimal experimental conditions were also obtained. The experimental results demonstrate that sul folobas being kind of linking-heat, acidophilic and self-supported bacterium with double characters can effectively remove inorganic and organic sulfur in coal. The superlatively desulfurization rate is up to 48.57% total sulfur and 41.71% inorganic sulfur within 10 d and its desulfurization rate can be greatly affected by the four factors above mentioned. Therefore, the optimum conditions of desulfurization are obtained by comprehensive experiment and they are as following: pH value 3, temperature 70°C, coal slurry concentration 10% and coal granularity 150 μm, respectively. Moreover, the repetition experimental results confirm that the desulfurization by sul folobas is steady. Foundation item: The National Advanced Technology Research and Development Project (863 Project 2002AA649220) Biography of the first author: HE De-wen, postdoctor, born in April 1968, majoring in solid waste pollution control and resource, environmental assessment and plan.     

以脱硫添加剂应对燃煤火电厂高硫煤的问题

我司设计入炉煤种硫份为0脱硫效率9浆液pH值维持5以上时脱硫系统S实际最大处理能力为26mg/m折合煤质含硫1通过采用脱硫添加剂,在保证脱硫效率大于9浆液运行pH值5的前提下,脱硫系统的S实际处理能力提高到3mg/m折合煤质含硫1有效解决了火电厂高硫煤的问题,提高了电厂的经济效益。     

氧化亚铁硫杆菌脱除煤中硫的研究

利用氧化亚铁硫杆菌对高硫煤进行了微生物脱硫研究．研究表明，微生物能降解高硫煤中的硫，而且随处理时间的延长脱硫率逐渐升高．煤样的粒度、细菌接种量、补加氮源对脱硫有一定影响．实验中还发现，对煤样进行酸预处理，然后再进行微生物脱硫，脱硫率可达46.3％。     

660MW机组脱硫吸收塔浆液pH值控制优化

随着国家节能减排工作的深入开展,对火电厂的排放指标的要求越来越严格,环保指标红线意识越来越得到重视,在煤炭的含硫量一定的情况下,如何利用现有的控制与调整手段,实现环保指标的低排放的问题,摆在生产一线人员的面前。通过对影响脱硫效率的主要因素分析,对原脱硫系统浆液p H控制策略存在的问题进行分析研究,提出有效的优化方案,以改善p H值调节品质,利用试验证明可优化p H值控制,提高p H控制品质;此举可进一步提高脱硫效率,是效益最大化、环保合法化的一个重要保障。     

煤的微生物脱硫的实验研究

煤中硫的脱出可以减轻对环境的污染,而煤的生物充是很有前景的一种脱硫方法,利用空气搅拌法,研究了内蒙古自治区酸性矿井水、土壤液、城市污未和工厂废液对乌达雀儿沟煤中硫的脱出能力,经过２ｄ细菌２和１５ｄ脱硫,发现除城市污水外,其余的均能脱掉煤中部分硫,硫脱除率２６．９５－３８．７７％;而且,中性环境与酸性环境有着几乎一致的硫脱除率。     

Desulfurization of coal by an electrochemical-reduction flotation technique

The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCI solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfurization ratio was also studied.The electrochemical-reduction processed coal was examined by X-ray diffraction, Fourier transform infrared spectroscopy and wet chemical analysis. The results show that electrochemical reduction converts hydrophobic pyrite in Nantong coal into hydrophilic FeS and S2 and leads to an increase in the concentration of hydroxyl groups and aliphatic moieties and a corresponding decrease in carboxyl and carbonyl groups, which enhances the flotation desulfurization of the coal.     

石灰石及盐类混合物在粉粒喷动床内的半干湿法脱硫

开发一种新型粉粒喷动床半干湿法脱硫过程。在这个过程中，喷动床为一个多相反应器。在喷动床中，二氧化硫与脱硫剂反应，脱除烟道气中的二氧化硫。实验采用石灰石作为脱硫剂，并考察操作条件对脱硫效率的影响。结果表明，脱硫效率受到几个因素的影响：钙硫比、饱和接近度、脱硫剂直径、粗粒子的静床层高度以及气体的表观流速。当石灰石粒径小于5μm、钙硫比大于1．5、饱和接近度为6℃时，脱硫效率可高于90％，而脱硫剂利用率超过60％。一些碱金属化合物可被用作提高脱硫效率和脱硫剂利用率的添加剂。实验结果表明：在喷动床烟道气脱硫过程中，添加氯化钠可显著提高脱硫效率。而且在脱硫浆料中，氯化钠与石灰石之比小于0．2时，脱硫效率随氯化钠浓度增加而增加。这个研究结果表明利用海水制备脱硫浆料成为可能。     

喷射旋液脱硫塔脱硫性能研究

煤炭燃烧后产生的大量二氧化硫造成了严重的污染问题。湿法脱硫是当今用于烟气脱硫的主要方法。介绍了一种新型的脱硫设备---喷射旋液脱硫塔,实验研究了操作条件对其脱硫性能的影响,并综合考虑对压降的影响,得到了较优的操作条件。研究表明该设备具有良好的脱硫除尘效果,双层塔盘的脱硫效率可达到９０％以上。     

Research on Factors Affecting Flotation and Desulfurization of Coal by Electrochemical Method

Influence of factors such as potential of electrolyte, electrolyzing time, concentration of electrolyte, and pH value on flotation and desulfurization of coal was researched. The result shows that the electrochemical reduction can enhance the desulfurization effect and increase the yield of clean coal under certain conditions. So it is an effective method.     

旋流板塔煤浆法烟气脱硫研究

煤浆法烟气脱硫是以煤浆洗涤含二氧化硫的烟气,二氧化硫溶于浆液形成亚硫酸,煤中黄铁矿与亚硫酸、氧气发生反应,亚硫酸被氧化为硫酸,从而实现烟气脱硫.反应过程中,煤中的黄铁矿硫也被转化为硫酸而浸出,反应产生的Fe3＋/Fe2＋又对脱硫反应起到了催化剂的作用.以旋流板塔为吸收设备,研究了煤浆法烟气脱硫过程中浆液温度、液气比、空塔气速及浆液固液比等操作参数对脱硫率的影响规律.试验表明,在其他条件不变的情况下,适当提高液气比、空塔气速及浆液固液比均有利于提高脱硫效果.随着烟气脱硫过程的进行,脱硫浆液中的总铁含量不断增加,说明煤中黄铁矿被不断浸出,故此法在脱除烟气中的二氧化硫的同时也降低了煤中黄铁矿硫含量.     

生物絮凝剂在处理洗煤废水中的应用

通过对白腐真菌的生物学培养特性研究,获得最佳培养条件：在转速160r／min、温度30℃、稻壳浸出液90mL、葡萄糖质量浓度35g／L、pH3．5的条件下,生长势最好;分析了煤水中煤泥颗粒组成,发现其粒度小于0．045mm的含量占55．93％,而大于0．25mm的含量仅占3．75％,说明煤泥水中细粒含量较多,靠自身重力难以沉降;探讨了pH、生物絮凝剂用量、搅拌方式和金属离子等单因素对煤泥水絮凝效果的影响,通过正交试验进一步优化了该菌所产絮凝剂对煤泥水絮凝效果的条件．结果表明当煤泥水质量浓度27．42g／L、助凝剂（CaCl2）质量浓度5．0g／L、二段式搅拌、pH11和絮凝剂体积浓度15mL／L时,其絮凝活性最佳,可达98．71％;进一步实验表明,絮凝活性物质绝大部分存在于细胞外,是微生物在发酵过程中菌体细胞产生的胞外分泌物．     

高硫煤还原分解磷石膏试验研究

简要介绍了磷石膏的组成、危害以及现状.利用高硫煤还原分解磷石膏进行了试验研究,得到了高硫煤还原分解磷石膏时,磷石膏在约1000℃时进行分解,并且在1 200℃达到最高的分解率与脱硫率.随着反应温度的升高,磷石膏的分解率与脱硫率在提高,同时磷石膏分解率达到97%的反应时间逐渐减少.利用高硫煤还原分解磷石膏,可以有效提高烟气中SO2的浓度,磷石膏与高硫煤摩尔比约为0.7时,SO2浓度达到最高约14%,增加了磷石膏再利用的经济效益.     

生物滴滤法脱除废气中SO2工艺的研究

优化生物滴滤塔的性能,以提高其对SO2废气的处理效率．在单因素实验的基础上,以气体流量、SO2浓度、温度及pH值作为考察因素,通过设计正交试验,研究其脱硫最佳工艺条件;在最佳工况条件下探讨不同入口浓度、不同填料层高度及喷淋量对脱硫效率的影响．结果表明,各因素对SO2去除率影响大小次序为SO2浓度〉温度〉气体流量〉pH值;最佳工艺条件为气体流量0．9m^3／h,SO2浓度1000mg／m^3,pH值2．3～2．4,温度28℃．脱硫率随填料层高度增加而增大,30L／h喷淋量的脱硫效果较优于24L/h,并且生物滴滤法比较适合于低浓度脱硫．     

多级多尺度烟气脱硫液柱塔的性能研究

为了探索液柱塔的最佳脱硫条件,以多级多尺度液柱塔为研究对象,采用压力旋转和扇形喷嘴进行喷射实验,得到液滴直径分布规律,并探索各因素对其脱硫效率的影响。研究结果表明:脱硫效率随着塔内风速、吸收液pH值、SO2入口浓度的增大而降低,随液气比增大而增大。采用不同喷嘴组合可以有效改善脱硫浆液的雾化效果,解决气液接触时间短以及雾沫夹带问题。在液气比1.5 L.m-3、SO2入口质量浓度300 mg.m-3条件下,脱硫效率可以达到96.5%。     

Modeling and process optimization for microbial desulfurization of coal by using a two-level full factorial design

The microbial sulfur removal was investigated on high sulfur content (1.9%) coal concentrate from Tabas coal preparation plant. A mixed culture of ferrooxidans microorganisms was isolated from the tailing dam of the plant. Full factorial method was used to design laboratory test and to evaluate the effects of pH, particle size, iron sulfate concentration, pulp density, and bioleaching time on sulfur reduction. Statistical analyses of experimental data were considered and showed increases of pH and particle size had negative effects on sulfur reduction, whereas increases of pulp density and bioleaching time raised microbial desulfurization rate. According to results of designing, and regarding statistical factors, the optimum values for maximum sulfur reduction were obtained; pH (1.5), particle size (?180 μm), iron sulfate concentration (2.7 mmol/L), pulp density (10%) and bioleaching time (14 d), which leaded to 51.5% reduction from the total sulfur of sample.     

麻疯树籽粕中毒蛋白的提取

研究了溶剂浸提法提取麻疯树籽饼粕中麻疯树毒蛋白时的各影响因素,考察了提取时间、提取温度、pH值、缓冲液浓度和无机盐浓度对麻疯树毒蛋白溶出的影响.结果表明:提取液pH值是影响麻疯树毒蛋白溶出的最重要因素,提取时间、缓冲液浓度及盐浓度对提取也有一定影响.通过正交试验获得最佳提取条件:提取时间3 h,提取温度25℃,提取液为浓度0.4 mol/L的NaCl溶液,pH=7.在此条件下得到的毒蛋白占去壳种仁的质量分数的0.39%.     

超声波辐射下煤的电化学脱硫研究

以NaCl溶液为电解质溶液,在超声波辐射下对高硫煤样进行超声电化学脱硫。采用正交试验法确定适宜的脱硫条件,通过单因素试验研究煤浆浓度、NaCl浓度、电解电压和电解时间对煤样脱硫率的影响,比较不同催化剂和电化学辅助手段对脱硫效果的影响。结果表明,电解电压为10V、电解时间为90min、煤浆浓度为20g／L、NaCl浓度为1．0mol／L、以FeCl2为催化剂时超声辅助电化学脱硫的效果最好,脱硫率达80．8％。煤质分析和红外光谱分析表明超声电化学不仅能脱除煤中的硫分,而且能有效地脱除其中的灰分并提高煤的发热量。     

四川煤的两液相法除灰脱硫研究

本文叙述研磨时间、溶剂、添加剂及其用量对两液相法净化煤的影响,比较了相同条件下不同煤样的净化结果.随煤种不同,除灰率达38～80%,减硫率为14～69%,无机硫脱除率为60～90%,并考察了净化过程中溶剂的分布情况.