中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
新型低气阻高效除尘器的研究与应用探索

文献类型:学位论文

作者黄亿苹
学位类别工程硕士
答辩日期2014-05
授予单位中国科学院研究生院
导师陈运法 ; 刘海弟
关键词高效除尘器   细颗粒   压降   缚尘剂
其他题名Research and application of a unique precipitator with high efficiency and low pressure drop
学位专业材料工程
中文摘要大气细颗粒物污染(PM2.5)因灰霾天气迅速增加而进入公众视野,引起了广泛的关注。要控制大气细颗粒物污染,必须从源头减少排放。传统除尘方法对细颗粒物的去除大都效率低下,仅有的高效细颗粒物去除设备以袋式除尘效率最高,但是其压降很大,对实际应用产生限制。因此,本文开发了一种由蜂窝陶瓷、聚苯丙烯扭线刷和缚尘剂组成的除尘模块,其创新之处在于:通过由蜂窝陶瓷与聚苯丙烯扭线刷构成的独特孔道结构过滤尘粒。这种孔道结构将拦截尘粒的滤料纤维分布在与气流方向垂直的各平面上,且在过滤过程中提供离心作用,从而实现低压降下的高效除尘。 采用TSI气溶胶发生器雾化聚苯乙烯小球溶液(PSL)作为测试尘源,用激光粒子计数器测定除尘模块的除尘效率。研究表明,随着除尘模块中聚苯丙烯扭线刷长度的增加,压降增加,除尘效率增高且更稳定。其中,除尘模块中扭线刷长度为4 cm时,对<3 μm的细颗粒除尘效率在80%以上;气流速度为0.53 m3/h时压降为30 Pa,远小于同样条件下测得的工业用除尘滤布的压降(603 Pa)。 为了提高除尘效率,在除尘模块中引入缚尘剂。缚尘剂的主要作用是在除尘模块表面形成液膜,提高对细颗粒的捕捉能力。本研究开发了两种缚尘剂,一种为复合型缚尘剂,另外一种为合成树脂缚尘剂。复合型缚尘剂采用了羧甲基纤维素钠(CMC)、聚丙烯酸钠(PAAS)、氯化钙(CaCl2)等几种成分。实验结果表明,经过缚尘剂增强后,相比于空白除尘模块,除尘效率得到了大幅度提高,也更稳定。其中,以1.25%CMC溶液作为缚尘剂时效果最佳:对0.3~0.5、0.5~1.0、1.0~3.0、3.0~5.0、5.0~10.0、>10.0 μm的颗粒除尘效率分别为97.20%、97.18%、96.87%、96.65%、95.41%、96.34%,总除尘效率为97.08%。 由于羧甲基纤维素钠分子量相对较小,其特性黏数、强度受到限制,因此,使用丙烯酰胺(AM)改性CMC,合成丙烯酰胺接枝的羧甲基纤维素树脂。调节羧甲基纤维素钠和丙烯酰胺不同的摩尔比,以过硫酸钾为引发剂,通过自由基聚合反应合成所需要的树脂。通过红外、热重、电镜等手段,验证了CMC-AM接枝共聚物的生成、CMC-AM聚合物较CMC较好的热稳定性和CMC-AM聚合物不同的表面形态。经过四种2.5%CMC-AM缚尘剂改性后的除尘模块相比于空白除尘模块,平均除尘效率都得到了大幅度提高且更为稳定。与之相关的研究会进一步开展。
英文摘要A growing number of people are concerned about fine particulate matter (particles with diameter less than 2.5 micrometer, PM2.5) which is one of main cause of haze in China. To control airborne fine particulate matter, we must reduce its emissions from industry. Although there are many emerging technologies in air pollution control equipment and processes, they are always inefficient to remove PM2.5. Only the fabric filter baghouse has high efficiency for removal of PM2.5, but it has a serious problem of high resistance pressure drop. A novel honeycomb ceramics precipitator module embedded with polystyrene propylene brush and dust suppressant was used for the collection of industrial exhaust particles. This precipitator with unique pore structure can distribute the sedimentation of dust particles on filter material fiber through different plane perpendicular to the flow direction, and introduce the centrifugal effect during the filtering process. Test aerosol was introduced using a TSI nebulizer that atomizes a prepared solution of PSL. The collection efficiency of precipitator module was tested by a dust particle counter. The experiment showed that with increasing the length of the brush, the pressure drop increases, and collection efficiency is higher and more stable. When the 4 cm brushes were introduced, collection efficiency was more than 80% for the fine particles (diameter <3 μm); resistance pressure drop was 30 Pa, while it is 603 Pa on the industrial filter with the condition of velocity in 0.53m3/h. In addition, dust suppressant were introduced into precipitator module for improve the collection efficiency. Liquid membrane of dust suppressant on the surface of precipitator module can enhance the capacity of collecting fine particulate matter. Two dust suppressants were exploited, one is composite dust suppressant, another grafting synthetic polymers dust suppressant. Several hygroscopicitys were used for composite dust suppressant, such as sodium carboxymethyl cellulose (CMC), polyacrylic acid sodium (PAAS) and CaCl2. Compared with the precipitator module without dust suppressant, the precipitator module with dust suppressant has higher and more stable collection efficiency. Among them, 1.25% CMC solution has the best efficiency for dust suppressant. The collection efficiency of the precipitator module was 96.34% for the particles with diameter more than 10 μm, 95.41% for 10.0 ~ 5.0 μm, 96.65% for 5.0 ~ 3.0 μm, 96.87% for 3.0 ~ 1.0 μm, 97.18% for 1.0 ~ 0.5 μm and 97.20% for 0.5 ~ 0.3 μm, respectively. The total collection efficiency is 97.08%. However, the various properties of CMC depend upon its molecular weight, so its intrinsic viscosity and strength is limited because the molecular weight is not big enough. Therefore, Attempts have been made to combine the best properties of CMC and acrylamide (AM) by grafting synthetic polymers onto CMC. The graft copolymers of CMC and AM were synthesized by potassium persulfate induced free radical polymerization techniques with different CMC AM ratio. The synthesized graft copolymers were characterized by FTIR, TGA and SEM. The FTIR result of the graft copolymers gives strong evidence of grafting. From the TGA curves, it is obvious that CMC-AM polymer is thermally more stable as compared to pure CMC. The SEM images show that morphology of CMC-AM polymers different. The collection efficiency of the precipitator module with 2.5% CMC-AM solution is higher and more stable as compared to the blank module. And related research will be developed further.
语种中文
公开日期2015-07-08
源URL[http://ir.ipe.ac.cn/handle/122111/15582]  
专题过程工程研究所_研究所(批量导入)
推荐引用方式
GB/T 7714
黄亿苹. 新型低气阻高效除尘器的研究与应用探索[D]. 中国科学院研究生院. 2014.

入库方式: OAI收割

来源:过程工程研究所

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