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响应面法优化袋式除尘器脉冲清灰性能 总被引:1,自引:0,他引:1
基于计算流体动力学的方法采用三维、可压缩、非稳态流动数学模型对袋式除尘器脉冲清灰过程进行了数值模拟,得到了滤袋内外压差,并与文献实验值进行了比较,验证了仿真模型的可靠性。基于响应面法研究了喷吹压力、喷吹高度、滤袋直径和滤袋长度对脉冲清灰性能的影响,得到这4个影响因子的二次多项式预测模型,并进行优化。结果表明,喷吹压力为0.3 MPa,喷吹高度为0.2 m,滤袋直径为0.16 m,滤袋长度为6 m时,内外压差峰值最优,优化结果与仿真模拟结果相差小于3%。研究结果为袋式除尘器脉冲清灰系统的设计与优化提供了重要参考。 相似文献
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《环境工程学报》2017,(4)
为探究新型扁式方框滤筒的清灰性能,在自建的脉冲喷吹实验台上,测得不同电磁阀、开孔型号、喷吹距离、喷吹压力下的侧壁压力峰值大小及其分布规律。通过进一步工业附粉,监测除尘器的阻力和清灰后的粉尘残余量,验证找到扁式方框滤筒的最佳喷吹清灰参数组合。结果表明:扁式方框滤筒的最佳开孔型号是7个7 mm孔,喷吹距离为20 mm;对于玉米秸秆粉尘,当过滤风速低于0.6 m·min~(-1)时,在1寸阀、0.2 MPa喷吹压力下可满足对其基本淸灰需求,且风速越小,清灰后的粉尘残余量越少,阻力也越小,低于150 Pa。另外,脉冲清灰过后,未被清除下来的粉尘多集中于扁滤筒的上部且是未正对喷吹孔的位置,如何进一步改善有待之后研究。 相似文献
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在自建的脉冲喷吹实验台上,利用Y—YD-7044型压电式传感器和MYD-8801加速度传感器,测试0120×2000mm覆PTFE膜无纺布滤袋在不同喷吹压力下,加文丘里与不加文丘里时的最大侧壁压力峰值和最大反向加速度,并对比计算了获得同样清灰强度时的脉冲阀一次喷吹耗气量。结果显示,添加文丘里能显著增大滤袋中下部最大侧壁压力峰值和整条滤袋上的最大反向加速度,即提高脉冲喷吹清灰强度;对应同样的喷吹压力,加文丘里时的平均最大侧壁压力峰值和平均最大反向加速度比不加文丘里时分别平均提高大约70%和50%;加文丘里获得同样清灰强度时的脉冲阀一次喷吹耗气量比不加文丘里时节省40%左右。证实对于脉冲喷吹清灰系统,添加文丘里能有效改善清灰效果以及减小能量?肖耗。 相似文献
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针对除尘滤筒脉冲反吹清灰均匀性差、强度不足的缺点,构建了脉冲喷吹滤筒除尘器CFD数值模型,考察了文丘里喷嘴和金锥滤筒组合条件下的清灰性能.结果 表明,无论是文丘里喷嘴还是金锥滤筒的使用或二者组合使用,滤筒内喷吹压力均为底部大而上部小;文丘里喷嘴和金锥滤筒可单独或组合式优化喷吹性能;在喷吹高度为150~550 mm时,喷吹强度和均匀性整体上随喷吹高度的增大而逐渐增强,当喷吹高度为350 mm时,文丘里喷嘴和金锥滤筒组合使用的优化效果最佳,喷吹强度和均匀性分别提高了1.72和1.96倍.本研究结果可为脉喷清灰滤筒除尘器的优化提供参考. 相似文献
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以袋式除尘器装置为研究对象,考虑射流偏移,建立了脉冲喷吹清洁的三维CFD数值模型,并进行实验验证;对喷嘴与文丘里管优化设计,修改数值模型,研究了低能耗下的脉冲喷吹清灰效果;在将改进的喷嘴与文丘里管进行工程应用的过程中,研究了其对大气粉尘排放的影响。结果表明,建立的三维CFD模型展现出了高瞬态行为和可压缩效应,即在射流中表现出涡流环与冲击单元现象。与孔喷嘴相比,改进后的喷嘴设计对射流偏移进行了调整,并且使滤袋内脉冲压力增加了5.1%~13.3%,提升了清灰效果。对比喉部直径为85 mm的文丘里管,无文丘里管的设计使得射流不易进入滤袋中,导致滤袋内脉冲压力降低了41.4%~46.3%,引起清灰效果的下降;减小文丘里管喉部直径,可以减少回流,提升滤袋内脉冲压力,改善清灰效果。对比原始装置,安装了改进喷嘴与文丘里管的袋式除尘器能明显降低大气粉尘排放,以上研究结果可为脉冲喷吹清灰除尘器的优化设计提供参考。 相似文献
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金属纤维滤袋可直接过滤高温烟气粉尘,解决高温烟气粉尘导致的环境、安全问题,对高温烟气的余热能源回收利用有非常重要的意义。目前,金属滤袋除尘器脉冲喷吹参数是依照传统纤维滤袋器设计的,存在着脉冲瞬时气流导致喷吹清灰失效问题。针对此问题,在脉冲喷吹实验平台上,通过改变喷吹压力、喷吹距离以及喷吹孔径,针对?130 mm×2 000 mm的金属滤袋,利用压力数据采集系统测试喷吹压力0.2~0.6 MPa、喷吹孔径6~14 mm、喷吹距离50~250 mm时,金属滤袋距顶部80、200、600、1 000、1 400和1 800 mm 6个部位的侧壁压力峰值,以探求针对金属滤袋的脉冲喷吹的合理参数。结果表明:2 m金属滤袋的最佳脉冲喷吹孔径为8 mm,最佳喷吹距离为200 mm,最佳喷吹压力为0.5 MPa;此条件下的P1(80 mm)、P2(200 mm)、P3(600 mm)、P4(1 000 mm)、P5(1 400 mm)、P6(1 800 mm)的侧壁压力峰值分别为1 000、1 686、839、746、749和2 005 Pa。金属滤袋的侧壁压力峰值大小排列呈下上中的规律。随着喷吹孔径的增大,最优喷吹距离有逐渐减小的趋势。金属滤袋的中、下部(距滤袋口600~1 400 mm)清灰将是未来金属滤袋清灰的重点关注部位。上述研究结果可为金属滤袋的推广发展提供参考。 相似文献
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《环境工程学报》2017,(3)
为了探究喷吹管开孔个数和开孔位置对长滤袋(160 mm×6 000 mm)清灰效果的差异,在自建脉冲喷吹实验台上,利用QSY8135压电式压力传感器,测试喷吹压力0.1~0.4 MPa,喷吹孔数4~8个时,不同开孔位置沿滤袋方向的侧壁压力。结果显示:脉冲喷吹压力0.2 MPa下的电磁阀一次喷吹实际耗气量是脉冲喷吹压力0.1 MPa的1.23倍,沿滤袋方向的平均侧壁压力是1.68倍,0.2 MPa的标准差为0.418 3,脉冲喷吹压力0.3 MPa下的电磁阀一次喷吹实际耗气量是喷吹压力0.1 MPa的1.48倍,沿滤袋方向的平均侧壁压力是2.34倍,0.3 MPa的标准差为2.430 4,得到本实验条件最佳喷吹压力0.2 MPa;喷吹压力0.2 MPa,当开孔个数不同时,沿喷吹管方向靠近电磁阀的第二个喷吹孔沿滤袋方向平均侧壁压力最小,开孔位置中最远离脉冲阀的孔沿滤袋方向平均侧壁压力最大,最小的侧壁压力是最大侧壁压力的0.539倍,当开孔数为8个,标准差0.170 5,值最小,清灰均匀性最好。对长滤袋喷吹管上开孔个数和喷吹位置的研究为袋式除尘器喷吹系统的改进和设计提供理论依据。 相似文献
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Alfred Eisner Jacob Tadmor 《Journal of the Air & Waste Management Association (1995)》2013,63(4):400-401
A number of key projects in the Environmental Protection Agency (EPA) particulate R&;D program having applicability to industry are presented. For electrostatic precipitators (ESP) there is presented the result of work on large diameter discharge electrodes which provide a decrease in penetration of up to a factor of 4 when compared to conventional small diameter electrodes. Also discussed is the multistage ESP which provides a collection efficiency that would require a collecting plate area 4 or 5 times larger with conventional ESP technology. The E-SOX technology makes use of the multistage concept to free up space in the ESP for SO2 removals of up to 90%. Electrostatically augmented fabric filtration provides a reduction in pressure drop of about 5 0% as compared to conventional fabric filtration. Wind tunnel modeling of windbreaks for material storage piles indicates a potential for providing engineering design data that would allow significant emission reduction caused by wind erosion 相似文献
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《国际环境与污染杂志》2011,10(2):304-314
This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies). 相似文献
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介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠 相似文献
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在实施ISO/IEC 17025:1999标准《检测和校准实验室能力的通用要求》过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核策划阶段的关键环节,提出审核范围确定、审核计划和抽样方案制订的质量控制要求,为有序高效地实施内部审核提供了技术方法。 相似文献
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Árpád Ambrus 《Journal of environmental science and health. Part. B》2013,48(3):435-442
Abstract A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits. 相似文献
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结合扬中生态环境的基本情况和存在的不足,进行了具体分析,对扬中未来生态建设的发展方向提出了建议及实施措施。 相似文献
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Morten E. Simonsen Martin B. S?rensen Erik G. S?gaard 《Environmental science and pollution research international》2012,19(9):3772-3781
Objective
This work aims to investigate the correlation between the photocatalytic activity determined by methylene blue bleaching (DIN 52980), stearic acid degradation, and degradation of acetone in gas phase.Method
The photocatalytic TiO2 coatings included in this investigation ranged from thin commercially available coatings (ActivTM and BioCleanTM) and ready to use suspensions (Nano-X PK1245) to lab-produced PVD and sol?Cgel coatings. XRD analysis of the photocatalytic coatings showed that all the coatings consisted of nanocrystalline anatase, although the thickness and porosity varied considerably.Results
The study showed that the reproducibility of the activity measurements was good. However, more importantly, the investigation showed that there is a good correlation between the activities determined by the different methods even though the characteristics of the photocatalytic coatings and the organic probe molecules varied considerably.Conclusion
The overall findings of this work suggest that there is a good correlation between the investigated methods. These results are promising for the future work concerning standardization of methods for determination of the activity of photocatalytic films. 相似文献19.
India has a very extensive coastline of about 7515 km, rich in diverse living resources. These resources continue to deteriorate with rampant harvesting or are altered for other uses such as aquaculture and fisheries. The present paper deals with degrading coastal habitats in northeastern India, and projects the intensity of the stress arising from the collection of tiger prawn seeds (Penaeus monodon) for aquacultural farms and molluskan shells for poultry feed and edible lime. Indiscriminate exploitation of these resources leads to a heavy reduction of the species concerned and other associated marine communities. The magnitude of such destruction has been quantified. The impacts of biodiversity loss and their after-effects on the ecobalance of this coastal system have become a matter of great concern to ecologists to maintain security and sustainability. The authors propose a public awareness program on themes relating to the importance of biodiversity for human livelihoods. 相似文献
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在实施ISO/IEC17025:1999标准《检测和校准实验室能力的通用要求》过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核实施阶段的关键环节,提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法,对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。 相似文献