【作者】 马东祝；

【导师】 何洪；

【作者基本信息】 北京工业大学 ， 应用化学， 2013， 博士

【摘要】 主要围绕乏风瓦斯富集和分离，进行了负载金属改性活性炭、KOH改性活性炭和活性炭纤维、高温焙烧改性活性炭等变压吸附分离吸附剂的研究工作，并进行了中试用吸附剂的工业化制备和中试实验。以吸附剂的分离系数α、吸附能力选择系数W、吸附选择参数S和吸附量V等为评价参数，以孔径、孔容、比表面积等为参考，进行改性碳材料吸附剂的筛选。活性炭中选择PA-1进行金属负载改性，10²0mesh椰壳炭进行高温焙烧和KOH活化改性，选择ZC1326作为ACF中最适合的改性材料。采用水热法负载金属改性活性炭PA-1进行了金属离子的选择，其中以Ti改性尤为突出。采用分离系数、吸附选择能力系数、吸附选择参数和在150kPa时的CH4吸附量来评价吸附剂的性能，并进行了常温常压穿透实验测试其吸附性能。分离系数α由PA-1的4.0变化为Ti-PA-1-160℃的4.3和Ti-PA-1-160℃-1100℃的3.9，吸附能力选择系数W也从PA-1和Ti-PA-1-160℃的2.8降至Ti-PA-1-160℃-1100℃的2.2，相应的吸附选择参数S为：11.20、12.04和8.58，但其在150kPa时对甲烷的吸附量V却从22.7cm³/g升至34.4cm³/g，增加了51.5%。1100℃N₂保护焙烧的Ti改性活性炭CH4常压穿透曲线的穿出点为111s，比未改性的活性炭和160℃水热方法Ti改性活性炭滞后了41%和50%。浸渍负载Sr改性活性炭表现出对N₂极低的吸附性能。采用KOH和活性炭混合法改性椰壳炭及KOH溶液浸渍法改性活性炭纤维进行实验研究。当KOH：C=2：1、碳化温度和活化温度分别为500℃和800℃、碳化时间和活化时间分别为1h和2h时，改性后的活性炭吸附效果最佳，对甲烷的吸附量V高达51.6cm³/g，分离系数α为4.2，吸附选择能力W系数为2.5，吸附选择参数S为10.50，分别比未改性前变化了+63.8%，-10.6%，+4.2%和-6.9%。当KOH浓度为13%、活化时间为40min、活化温度为800℃时，改性后的活性炭纤维吸附效果最佳，分离系数α为4.2，吸附选择能力系数W为2.4，吸附选择参数S为10.08，虽然三个参数比未改性前分别降低了4.5%、11.1%和15.2%，但其对甲烷的吸附量V却达到49.4cm³/g，比未改性前增加了48.3%。采用高温焙烧对活性炭进行改性研究。考察了不同焙烧温度、不同焙烧时间、不同焙烧气氛对椰壳炭分离CH4/N₂性能和物理性能的影响，采用分离系数、吸附选择能力系数、吸附选择参数和在150kPa时的CH4吸附量来评价吸附剂的性能，并进行了常温常压穿透实验测试其吸附性能。在实验研究范围内发现N₂保护下600℃焙烧4h时，改性椰壳炭的物理性能没有明显改变的情况下，具有良好的吸附分离性能。此时改性后的活性炭分离系数α为4.8，比未改性前的4.7增大了2.1%；吸附选择能力系数W为2.2，比未改性前的2.4降低了8.3%，吸附选择参数S为10.56，比未改性前的11.28降低了6.4%，对甲烷的吸附量V为36.0cm³/g，比未改性前的31.5cm³/g增大了14.3%；常压穿透曲线穿出点为172s，比未改性前的55s滞后了212.7%。中试用吸附剂的工业化制备采用氮气保护650℃焙烧4h、1mol/LHCl溶液浸泡24h、洗涤和热风烘干工艺，制得烘干后的活性炭为3745kg，总的损失率为22.4%。搭建了一套原料气进气量为1000m³/h的煤矿乏风瓦斯分离富集中试试验装置。利用乏风减量装置，通过旋流富集在出口中心部分最高可获取的甲烷浓度可达0.3%。在乏风瓦斯平均浓度约为0.2%的条件下，吸附分离富集系统出口的瓦斯浓度≥1%，回收率可达到50%左右。更多还原

【Abstract】 For methane enrichment and separation of ventilation air methane （VAM） in coalmine, carbon adsorption material was studied by supported metal modification,roasting modification, KOH modification for pressure swing adsorption （PSA）.Adsorbent industrialization preparation and pilot scale experiment were carried.The separation factor α, selectivity coefficient of adsorption capacity W,adsorption selection parameter S and adsorption amount of capacity V were selectedas the evaluation parameters. The pore size, pore volume, surface area were taken asreference. Carbon material adsorbent was screened for modification. PA-1wasselected for supported metal modification,10²0mesh coconut shell charcoal forroasting modification, KOH modification. ZC1326was chosen as the most suitableACF material.The metal ions for PA-1modification were chosen by hydrothermal method, inwhich Ti modification was particularly prominent. The evaluation of adsorbent wastaken according as separation factor, selectivity coefficient of adsorption capacity,adsorption selection parameter and adsorption capacity of CH4at150kPa. Andatmospheric penetration test was taken to evalute adsorption properties of adsorbentmodified. The separation factor α changes from4of PA-1to4.3of Ti-PA-1-160℃andto3.9of Ti-PA-1-160℃-1100℃, selection coefficient of adsorption capacity W alsodecreases from2.8of PA-1and Ti-PA-1-160℃to2.2of Ti-PA-1-160℃-1100℃,corresponding adsorption selection parameter S is11.20,12.04and8.58, but itsmethane adsorption amount V at150kPa increases from22.7cm³/g to34.4cm³/g,increasing51.5%. Breakthrough point of atmospheric penetration curve is111s forTi-PA-1-160℃-1100℃. Respectively, it was lagged by41%and50%compared withPA-1and Ti-PA-1-160℃. Sr modified activated carbon shows very low adsorptionproperties of N₂.Coconut shell activated carbon modified by KOH and activated carbon mixedmethod, activated carbon fiber modified by KOH solution dipping method. WhenKOH:C was2:1, carbonization temperature and activation temperature were500℃and800℃, of carbonizationtime and activation time were1h and2H, modified ACadsorption properties were the best. CH4adsorption amount V reaches51.6cm³/g,separation factor α is4.2, selection coefficient of adsorption capacity W is2.5and adsorption selection parameter S is10.50. Respectively, changes are+63.8%,-10.6%,+4.2%and-6.9%than the unmodified activated carbon. When KOH concentration is13%, activation time is40min, activation temperature is800℃, modified ACFadsorption properties were the best. Separation factor α is4.2, selection coefficient ofadsorption capacity W is2.4, and adsorption selection parameter S is10.08.Parameters decreases4.5%,11.1%and15.2%than the unmodified, but CH4adsorption capacity V reaches49.4cm³/g and increases48.3%than the unmodified.Roasting method was adopted for AC modification. The effects of roastingtemperature, roasting time and roasting atmosphere on coconut shell charcoalseparation of CH4/N₂and physical performance were studied. In the experiment, thebetter condition is found that it is roasted at600℃for4H in N₂atmosphere. In thiscondition, modified coconut shell charcoal has no obvious change on physicalproperties and has good separation performances. Separation factor α is4.8,increasing2.1%than4.7of unmodified AC; selection coefficient of adsorptioncapacity W is2.2, reducing8.3%than2.4of unmodified AC, adsorption selectionparameter S is10.56, reducing6.4%than11.28of unmodified AC, CH4adsorptioncapacity V reaches36.0cm³/g, increasing14.3%than31.5cm³/g of the unmodified AC.Breakthrough point of atmospheric penetration curve is172s and lagged by212.7%compared with55s of the unmodified AC.Adsorbent industrialized preparation process is roasting at650℃for4h in N₂atmosphere, dipping in1mol/LHCl solution for24h, washing and drying. Activatedcarbon after drying is3745kg, and the total loss weight is22.4%. A test device wasbuilt for coal mine VAM enrichment and separation. The volume of feed gas is1000m³/h. Using ventilation air reduction device, the maximum concentration of CH4can reach0.3%in export center after hydrocyclone enrichment. When the CH4average concentration is about0.2%, the CH4concentration of export for adsorptionseparation and enrichment system is larger than or equal to1%, the recovery rate canreach about50%.更多还原