共查询到18条相似文献,搜索用时 718 毫秒
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尹艳 《煤炭加工与综合利用》2013,(2):50-52
通过正交试验分析多粘类芽孢杆菌降解褐煤时,煤样粒度、煤浆浓度、菌液用量及降解时间4因素对褐煤微生物降解率的影响;结果表明,煤样粒度对褐煤微生物降解率的影响最大。 相似文献
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燃烧含硫煤炭会释放硫氧化物,导致雾霾、酸雨等环境问题,因此,煤中硫的降低或脱除至关重要。选用能够降解多环芳烃的恶臭假单胞菌和能够降解长链烷烃的茫崖诺卡氏菌对含硫量为2.66%的山西晋城中高硫煤进行微生物脱硫,通过单因素实验和正交实验探究了煤样粒度、煤浆质量浓度、脱硫时间、细菌接种量、培养基pH和培养温度对微生物脱除煤中硫的影响。利用红外光谱仪、X射线衍射仪和扫描电镜对原煤和脱硫后煤样进行了分析表征。结果显示恶臭假单胞菌最佳脱硫条件是:煤样粒度0.075 mm~0.125 mm,煤浆质量浓度0.008 g/mL,培养时间10 d,细菌接种量0.2 mL/mL,培养基pH 6.0、培养温度30℃。茫崖诺卡氏菌的最佳脱硫条件除了培养基pH为7.0与恶臭假单胞菌培养基pH不一样外,其他条件均一致。恶臭假单胞菌和茫崖诺卡氏菌在最佳脱硫条件下的脱硫率分别为38.0%和39.8%,脱硫后煤样中的全硫质量分数分别为1.65%和1.60%,表明经微生物脱硫后煤样含硫量均符合发电用煤S4等级(1.50%t)≤2.00%)。与原煤相比,脱硫后煤样的黄铁矿峰强度有所降低,部... 相似文献
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经对能源条件、细菌接种量、氮素营奍、煤粉粒度、煤浆浓度和酸预浸洗煤样等影响煤炭微生物脱硫的因素进行研究,确定了最佳条件。在12天浸出时间内,煤炭总硫脱除率可达53.0%。 相似文献
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选取典型低变质程度神木柠条塔(NTT)煤,进行球磨式连续型粒度级配提高水煤浆浓度(一定量的水煤浆试样在105℃~110℃干燥至恒重,干燥后试样质量占原样质量的百分数)和成浆性的研究。在不同球磨条件下,考察球磨时间、球磨速度对成浆浓度、流变特性和稳定性能的影响规律,研究粒度级配前后浆体表面润湿性、表面电负性、微观形貌的性能变化对NTT煤成浆性的影响,利用分形维数的计算,进一步探究了粒度级配对提高NTT煤制浆浓度的影响机理。结果表明:在级配M煤样(D50=79.02μm)与M6煤样(D50=8.727μm)的质量比为8∶2时,成浆浓度与未级配煤样相比提高了约4%;不同球磨条件下的煤样按照不同的质量比进行混合制浆时,初始添加细颗粒使浆体表面的润湿性增强,降低了浆体的性能,当粗细颗粒的质量比大于6∶4时,表面润湿性的变化较小;级配样的成浆浓度与Zeta电位的绝对值呈正相关;当级配煤样之间粒径相差逐渐变大,小颗粒填充到大颗粒孔隙中,增加了空间堆积率,提高了制浆浓度,但随着细颗粒的质量分数增大,大颗粒孔隙被撑开,煤粒空间堆积率下降,制浆浓度降低;M煤样与M6煤样在质量比为8∶2时,相比于其他级配浆体,分形维数达到最大(2.460),成浆浓度达到最高(63.03%)。 相似文献
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分析了原煤破碎级对浮沉试验结果的影响,说明随着煤样最大标称粒度的减小,煤样精煤产率变化很大,煤样破碎的粒级越小,对精煤产率的影响越大,精煤产率也就越高。万峰原煤不同最大粒度浮沉试验表明:对于最大标称粒度不大于50 mm的煤样,煤样经破碎后,浮沉试验精煤产率提高了16.41%,中煤、矸石产率分别降低了9.43%和1.16%;说明煤样经破碎后得到了进一步解离,精煤产率增加明显,结算时,公司需要额外支付多余的贷款。对于最大标称粒度大于50 mm的煤样,原煤筛分、浮沉试验结果显示,实际+0.5 mm原煤浮沉精煤产率为42.75%,若按汽车采样机所采煤样50~0.5 mm精煤产率55.25%上报,则精煤产率增加了29.24%,公司要多支付实际上不存在的这部分精煤产率的价格,损失重大;因此,必须将汽车采样机所采煤样的浮沉试验结果与+50 mm煤样浮沉产率结合修正后,才能得出煤样的真实浮沉试验结果。 相似文献
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提出了一种应用钙基脱硫剂脱除冶炼烟道气中高浓度SO_2并回收硫单质的方法。通过热力学模拟多种硫化物与SO_2之间的反应,筛选得出硫化钙(Ca S)适合作为化学链脱硫技术的脱硫剂,它在400~650℃范围内可将SO_2还原为单质硫,生成的固相产物为Ca SO_4而非Ca O。通过固定床反应器内的脱硫实验,发现温度对脱硫率和硫单质回收率影响较大。在400~650℃范围内温度越高,脱硫率和硫单质回收率越大;当温度高于600℃时,脱硫率和硫单质回收率基本相等。提高空速,则会降低脱硫率和硫单质回收率,但两者的差值随空速增大逐渐减小。当烟气中SO2浓度小于1%时,脱硫率维持在99.8%基本不变;SO_2浓度升至3.45%后,平均脱硫率急剧下降至92.1%;SO_2浓度越高,平均脱硫率越低。硫单质回收率随SO_2浓度增大存在一最佳范围。在脱硫反应后期,粒径较大的脱硫剂颗粒脱硫性能较低。SEM照片表明了脱硫剂颗粒随反应温度的升高团聚现象更为明显,XRD表征证明了反应中SO_2气体被还原为升华硫颗粒。 相似文献
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通过分析煤样性质,说明原煤中无机硫主要以硫化铁硫为主,有机硫较高,仅依靠物理方法很难达到理想脱除效果。通过煤粉高梯度磁选试验研究了磁介质、磁通密度、脉冲对煤炭磁选效果的影响。结果表明:聚磁介质选用不加铜套细网介质,当磁通密度为1.295 T,脉冲为25次/min时,煤粉湿法高梯度磁选脱硫效果最好,此时硫分为1.59%,精煤产率为85.44%,脱硫率为31.87%,脱灰率为38.17%,黄铁矿硫脱除率为45.02%。通过正交试验确定了最佳高梯度磁选条件为:煤粉粒度0.075 mm,磁通密度1.295 T,脉冲25次/min,可得到硫分1.35%,灰分10.37%的磁选精煤产品。最后对磁选精煤进行再浮选试验,得到最佳浮选条件为:石灰500 g/t,捕收剂1360 g/t,起泡剂90 g/t,可获得产率76.29%,硫分1.28%,灰分8.14%的精煤,产品脱硫率为57.73%,脱灰率为58.52%,黄铁矿硫脱除率为84.56%。采用磁选-浮选综合流程,煤粉基本达到理想的脱硫降灰效果,可作为煤种脱硫降灰技术方案的参考。 相似文献
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利用嗜酸氧化亚铁硫杆菌对典型川煤进行脱硫实验研究,考察了FeSO4质量、Tf菌接种量、处理时间、煤浆质量分数、煤粉粒度等因素对脱硫效果的影响,并对煤系嗜酸氧化亚铁硫杆菌(煤系Tf菌)和非煤系氧化亚铁硫杆菌(非煤系Tf菌)的煤炭脱硫效果进行了比较。结果表明:煤系Tf菌最优条件为:FeSO4质量为0,接种量为9 mL,处理时间为28 d,煤浆质量分数为10%,煤粉粒度为0.150~0.075 mm,其脱硫率分别为43.35%、48.50%、49.36%、42.06%和57.71%;非煤系Tf菌最优条件为:FeSO4质量为1.12 g,接种量为9 mL,处理时间为28 d,煤浆质量分数为10%,煤粉粒度为0.150~0.075 mm,其脱硫率分别为20.60%、42.06%、50.64%、39.06%和53.30%。 相似文献
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一种高有机硫煤的化学药剂脱硫研究 总被引:6,自引:0,他引:6
选择复合脱硫剂在酸性条件下研究脱硫条件(煤浆浓度、处理时间、复合脱硫剂的浓度及溶液酸度)对高有机硫煤总硫、无机硫和有机硫脱硫率的影响.研究表明,煤浆浓度越低、处理时间越长、复合脱硫剂的浓度越大、处理溶液的酸度越大,总硫、无机硫和有机硫的脱硫率越大,最后对处理液和脱硫精煤进行了组分分析,探讨了酸性条件下复合脱硫剂脱除煤中总硫的反应及脱硫机理. 相似文献
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Zhiling Li 《Fuel Processing Technology》2010,91(9):1162-5014
The present work describes the desulfurization of coal using mildly reductive method. Both a Yanzhou and a Yanshan coal (referred to as YZ and YS coal, respectively), were treated in an aqueous media employing sodium borohydride (NaBH4) as reducing agent, which is a well known hydrogen storage. Reaction variables investigated include concentration of reductant, time, pH of initial media, temperature, stirring rate and particle size. The calorific values and ignition temperatures of the coal samples before and after treatment were determined. Results show that the total sulfur removal improved with the increase in the concentration of NaBH4, shaking rate and temperature and with the decrease in the particle size. Meanwhile, decreasing the particle size from − 250 to − 109 μm increased the organic sulfur removal by more than six times for either of the coal samples. Considering economic rationality and operational convenience, the desulfurization conditions determined were 1.6 mM of NaBH4 concentration, − 109 μm of particle size, neutral pH of initial media, 1 min of treated time, 100 rpm of shaking rate, 30 °C of temperature. This led to 23.8% and 59.0% reduction in the pyritic, 70.4% and 100% reduction in the sulfate, and 11.0% and 15.0% reduction in the organic sulfur, giving 31.3% and 40.8% reduction in the total sulfur for the YZ coal and the YS coal, respectively. Moreover, this resulted in the increase in the calorific values by 3.4-6.9% and the decrease in the ignition temperatures by 2-21 °C for the coal samples. The desulfurization method described here is extremely rapid, convenient, inexpensive and mild, and therefore, has considerable technological interest. 相似文献
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以北宿煤为原料,利用微波选择性加热的特点,考察了微波辐照时间、煤样粒径、NaOH等因素对高硫煤磁性强化磁选脱硫的影响,同时考察了微波-NaOH饱和溶液联合处理对北宿煤磁选脱硫的影响。研究表明,不同粒径的煤样的最大脱硫率存在一个最佳微波辐照时间,而微波-NaOH联合处理法脱硫效果更为显著。对煤样进行微波预处理后,可以根据需要控制NaOH饱和溶液用量达到较为理想的脱硫效果。 相似文献
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Coal desulfurization prior to usage is a preprocessing in order to achieve clean fuel and reduce environmental impacts such as acid rain. Desulfurization of Tabas Mezino coal was conducted with two consecutive steps of froth flotation at ambient temperature followed by leaching at various conditions. Reducing the ash content of Mezino coal by 35.7 wt.% and its total sulfur content by 36.9% using froth flotation process was successful. HCl and HNO3 were used, separately, to leach the floated coal, and the effectiveness of each acid on Mezino coal desulfurization was investigated. Nitric acid was found to be much more effective than HCl and the effects of reaction time, acid concentration and temperatures as well as stirring speed were studied as major parameters in the nitric leaching process. Taguchi orthogonal experiment with the above mentioned parameter elements; one at three levels was used to optimize the experiment parameters by the analysis of variances. Applying of the Taguchi technique significantly reduced the time and cost required for the experimental investigation. The findings indicated that acid concentration, with a high contribution, had the most dominant effect on desulfurization performance, followed by temperature, stirring speed and time. Accordingly, the optimum condition was obtained as, temperature: 90 °C., acid concentration: 30%., and stirring rate: 1000 rpm. The total sulfur and ash removal after flotation and leaching at optimum condition reached to 75.4 and 53.2% respectively that is a remarkable result compared to the previous works. 相似文献
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