喷吹管对滤袋清灰性能的影响

为了探究喷吹管开孔个数和开孔位置对长滤袋（φ160 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。     

Nickel recovery from electronic waste II Electrodeposition of Ni and Ni–Fe alloys from diluted sulfate solutions

This study focuses on the electrodeposition of Ni and Ni–Fe alloys from synthetic solutions similar to those obtained by the dissolution of electron gun (an electrical component of cathode ray tubes) waste. The influence of various parameters (pH, electrolyte composition, Ni²⁺/Fe²⁺ ratio, current density) on the electrodeposition process was investigated. Scanning electron microscopy (SEM) and X-ray fluorescence analysis (XRFA) were used to provide information about the obtained deposits’ thickness, morphology, and elemental composition. By controlling the experimental parameters, the composition of the Ni–Fe alloys can be tailored towards specific applications. Complementarily, the differences in the nucleation mechanisms for Ni, Fe and Ni–Fe deposition from sulfate solutions have been evaluated and discussed using cyclic voltammetry and potential step chronoamperometry. The obtained results suggest a progressive nucleation mechanism for Ni, while for Fe and Ni–Fe, the obtained data points are best fitted to an instantaneous nucleation model.     

Energy-efficient modification of reduction-melting for lead recovery from cathode ray tube funnel glass

Lead can be recovered from funnel glass of waste cathode ray tubes via reduction melting. While low-temperature melting is necessary for reduced energy consumption, previously proposed methods required high melting temperatures (1400 °C) for the reduction melting. In this study, the reduction melting of the funnel glass was performed at 900–1000 °C using a lab-scale reactor with varying concentrations of Na₂CO₃ at different melting temperatures and melting times. The optimum Na₂CO₃ dosage and melting temperature for efficient lead recovery was 0.5 g per 1 g of the funnel glass and 1000 °C respectively. By the reduction melting with the mentioned conditions, 92% of the lead in the funnel glass was recovered in 60 min. However, further lead recovery was difficult because the rate of the lead recovery decreased as with the recovery of increasing quantity of the lead from the glass. Thus, the lead remaining in the glass after the reduction melting was extracted with 1 M HCl, and the lead recovery improved to 98%.     

660MW机组烟气循环流化床干法脱硫塔入口气流分布的试验研究

以某火电厂2×660MW机组循环流化床干法脱硫气流模拟试验为研究对象,采用速度分布不均匀度的概念,详细研究各种工况下入口烟道导流形式对脱硫塔文丘里速度场分布的影响。研究表明。通过合理设置入口烟道的导流装置,可满足各种工况下CFB-FGD脱硫塔的文丘里管段和反应器段的气流均布,为干法脱硫大型化的气流分布试验研究提供借鉴。     

加热炉盘管的腐蚀与防护

加热炉通常采用原油或渣油为燃料,对炉管内流过的原油进行加热,以降低原油黏度,减少输送阻力.炉内盘管在高温及腐蚀性介质的作用下,常会发生腐蚀穿孔.对腐蚀发生的位置、原因进行了分析,并有针对性地提出了防护改进措施.     

饮食业油烟气快速检测-检气管法

针对GB18483—2001附录A《饮食业油烟采样方法及分析方法》在执法成本与执法手段上的局限性,提出了替代的饮食业油烟气快速检测——检气管法。通过对检气管法原理．方法可行性,经济成本的分析,认为利用检气管,通过该管内的油烟气使显色层显色。与标准色列进行比较．可以快速定性判别油烟气的浓度达标情况。检气管法较适用于低浓度(1～5mg／m^3)油烟气的检测判别,对排放标准2mg／m^3的油烟浓度能够给予判别是否超标或达标。     

Reduction–melting combined with a Na2CO3 flux recycling process for lead recovery from cathode ray tube funnel glass

With large quantity of flux (Na₂CO₃), lead can be recovered from the funnel glass of waste cathode-ray tubes via reduction–melting at 1000 °C. To reduce flux cost, a technique to recover added flux from the generated oxide phase is also important in order to recycle the flux recovered from the reduction–melting process. In this study, the phase separation of sodium and the crystallization of water-soluble sodium silicates were induced after the reduction–melting process to enhance the leachability of sodium in the oxide phase and to extract the sodium from the phase for the recovery of Na₂CO₃ as flux. A reductive atmosphere promoted the phase separation and crystallization, and the leachability of sodium from the oxide phase was enhanced. The optimum temperature and treatment time for increasing the leachability were 700 °C and 2 h, respectively. After treatment, more than 90% of the sodium in the oxide phase was extracted in water. NaHCO₃ can be recovered by carbonization of the solution containing sodium ions using carbon dioxide gas, decomposed to Na₂CO₃ at 50 °C and recycled for use in the reduction–melting process.     

辐流式斜管沉淀池处理生活污水的实验研究

斜管沉淀池是指在沉淀区内设有斜管的沉淀池。在平流式或竖流式沉淀池的沉淀区内利用倾斜的平行管或平行管道分割成一系列浅层沉淀层,被处理的和沉降的沉泥在各沉淀浅层中相互运动并分离。根据其相互运动方向分为逆(异)向流、同向流和逆向流三种不同分离方式。每两块平行斜板间相当于一个很浅的沉淀池。辐流式沉淀池半桥式周边传动刮泥活性污泥法处理污水工艺过程中沉淀池的理想配套设备适用于一沉池或二沉池,主要功能是为去除沉淀池中沉淀的污泥以及水面表层的漂浮物。一般适用于大中池径沉淀池。辐流式沉淀池采用机械排泥,运行较好,设备较简单,排泥设备已有定型产品,沉淀性效果好,日处理量大,对水体搅动小,有利于悬浮物的去除。本研究通过掌握斜管沉淀池的构造功能及沉淀原理、通过改变运行因素来验证斜管沉淀池的处理效率。     

Glial fibrillary acidic protein in amniotic fluids from pregnancies with fetal neural tube defects

The glial fibrillary acidic protein (GFAP) is the subunit protein of intermediate filaments in astrocytes and closely related cell types. By means of an enzyme immunoassay we have determined the concentration of GFAP in amniotic fluids from normal pregnancies and from pregnancies complicated by various fetal malformations. The group of 20 cases of fetal anencephaly had a significantly higher mean amniotic fluid GFAP concentration (115 μg/1±133.6 (S.D.), range 6–378 μg/1) than the control group of 117 normal pregnancies (13 μg/1k±5.5 (S.D.), range 0–31 μg/1), (P<0.001). Two cases of fetal encephalocele likewise had very high amniotic fluid GFAP concentrations. None of the other cases of fetal malformations investigated, including 12 cases of spina bifida, had increased amniotic fluid GFAP concentrations. We conclude that determination of the amniotic fluid GFAP concentration may give additional information in the prenatal diagnosis of fetal nervous system malformations.     

真空采血管顶空气相色谱法检测水中三氯甲烷、四氯化碳

采用真空采血管顶空填充柱气相色谱法测定水中三氯甲烷和四氯化碳,结果表明,三氯甲烷在10.0～50.0μg/L,四氯化碳在0.5～4.0μg/L浓度范围内呈良好线性关系,其r值分别为0.9994和0.9998;三氯甲烷和四氯化碳RSD分别在1.64%~2.27%和1.45%~2.40%之间;加标回收率分别在97.0%~103.5%和94.0%~103.2%之间。该方法操作简单,具有较好的灵敏度和准确度,适用于水中三氯甲烷和四氯化碳的检测。