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581.
湿法烟气脱硫法鼓泡反应器的气液传质建模   总被引:6,自引:0,他引:6  
利用双膜理论对湿法烟气脱硫法鼓泡反应器气液传质建立数学模型。通过鼓泡反应的钠碱脱硫实验来验证模型,得到的模型计算结果和实验相吻合。利用模型,通过改变的初始参数来研究对传质的影响。结果表明,提高气流速度、进气浓度、吸收液柱高度和吸收液浓度,有利于传质吸收,提高鼓泡反应器的传质系数和脱硫效率。  相似文献   
582.
 区域废水污染物排放总量控制是当前环境影响评价和环境规划中探讨的重要课题。天津市大港石化发展规划区占地约35km2,是一个已具一定规模并在迅速发展的石油化工工业区。本文从最终受纳水体开始,采取反向递推分析方式,确定了该规划区区域废水CODCr总量控制目标,并分析了该规划区区域废水CODCr排放量削减的可行性。  相似文献   
583.
生态经济效率环境管理发展的关系探讨   总被引:11,自引:0,他引:11  
廖红  朱坦 《上海环境科学》2002,21(7):448-451
通过对生态经济效率的概念及其发展、生态经济效率与可持续发展的关系,以及生态经济效率还没有得到进一步发展的原因进行分析,阐述了如何提高生态经济效率的战略目标与措施。提出了在地方和区域、工业企业范围内运用生态经济效率的必要性,并指出生态经济效率研究与运用的关键,以期为我国环境管理提供借鉴。  相似文献   
584.
旋流板塔内石灰湿法烟气脱硫的试验研究   总被引:14,自引:3,他引:14       下载免费PDF全文
试验研究了在旋流板塔内以石灰湿法进行烟气脱硫率的影响,并对试验结果进行了分析讨论,得出了回归关联式。本研究为工业装置的设计、操作和运行提供了所必需的基础数据。  相似文献   
585.
Gaseous volatiles from wastewater samples taken from a local sewage treatment plant were air-stripped and trapped onto Tenax GC. These volatiles were then thermally desorbed and subsequently analyzed using a gas chromatograph coupled to a mass spectrometer (GC-MS). The results show that saturated aliphatic and aromatic hydrocarbons were the most dominant compounds found in the sewage gaseous volatiles. Other compounds found were chlorinated hydrocarbons, organic acids, sulfides and phenols. A wide variety of gaseous volatiles were found in the raw wastewater, the primary clarifier effluent, the pre-aeration wastewater and the sludge samples. A comparison of the gas chromatograms for the pre- and post-aeration wastewater shows that many odorous gaseous volatiles were removed during the aeration process in the treatment plant.  相似文献   
586.
A study of the noise generated by hand-held pneumatic rock drills at 15 road works locations in Hong Kong was conducted in 1989. The locations of road construction works were identified over one week period. Sound pressure levels (SPL) and band frequency analysis were measured with the integrated sound level meter at the level of the operator's ears. The sound levels for all 15 operators exceeded the local statutory limit of 90 dBA. The average sound level was 107.4 dBA and the corresponding continuous equivalent level adjusted to 8 hours or L eq (8h) was 104.8 dBA. The sound levels for the octave frequencies from 125 Hertz to 8000 Hertz were all in excess of 90 dBA. Estimates of the risk of developing hearing impairment for conversation speech among the operators were 18% and 42% after 5 and 10 years of exposure, respectively. Although there is adequate statutory control to restrict and reduce the hazards caused by noise at road construction works to the workers and to the public at large, no noise control measures were noted at the work sites and none of the operators used hearing protection. This situation was compounded by the short-term nature of road works and the high mobility of the operators.  相似文献   
587.
Poly(sodium 6-acrylamidocaproate), poly(sodium 11-acrylamidoundecanoate), poly(sodium 11-N-methylacrylamidoundecanoate) and poly(sodium 11-N-ethylacrylamidoundecanoate) have been synthesized. The performance of these anionic polyelectrolytes as coagulant aids in water treatment was assessed by the jar test. The effects of polymer dosage and pH on their performances were investigated in order to establish the optimum flocculation conditions. The effectiveness of these polyelectrolytes as well as a commercially available cationic polyamine organic coagulant aid was compared in terms of floc size, settling rate and the quality of treated water. Poly(sodium 6-acrylamidocaproate) and poly(sodium 11-acrylamidoundecanoate) were superior to poly(sodium 11-N-methylacrylamidoundecanoate) and poly(sodium 11-N-ethylacrylamidoundecanoate), and they are as effective as the commercial cationic coagulant aid.  相似文献   
588.
An experimental investigation is presented in this paper on the vapor compression refrigeration cycle used in an ice-making machine with a multi-channel evaporator. To study the operation performance of the refrigeration system in the ice-making machine, the fluid temperature distribution in multi-channel evaporating coils are tested and the dynamic variations in each cooling loop are investigated during the ice-generating phase. The results show that the external cooling loops have the largest temperature fluctuations caused by the large initial refrigerant injecting mass flow and the external environmental disturbances. For the inner cooling loops, the related temperature profiles of different test points have relative stable variations. To reduce the temperature fluctuations of the outside loops, it is suggested to reduce the initial refrigerant mass flow and adjust the initial opening of the thermal expansion valve. Moreover, it is the normal phenomenon for the slight temperature variations for the temperature curves of different test points, caused by the adjustment of thermal expansion valve. During the ice-making process, both the sensible heat removal phase and latent heat removal phase are experienced successively. To remove the sensible heat of water, the refrigerant system is operating in high efficiency with test points having a rapid linear temperature reduction. While for eliminating the latent heat of ice, it requires much more power supply, the relating test points have a temperature decrease with fluctuations. To improve the operation performance of ice machine, some suggestions and improvements are proposed.  相似文献   
589.
Al substitution in goethite is common in soils, and has strong influence on the structure and physicochemical properties of goethite. In this research, a series of Al-doped goethites were synthesized, and characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The adsorption behavior of these samples towards PO43 − was also investigated. Characterization results demonstrated that increasing Al content in goethite led to a reduction in crystallinity, increase in specific surface area (SSA), and morphology change from needle-like to granular. Rietveld structure refinement revealed that the lattice parameter a remained almost constant and b slightly decreased, but c was significantly reduced, and the calculated crystal density increased. EXAFS analysis demonstrated that the Fe(Al)–O distance in the structure of the doped goethites was almost the same, but the Fe–Fe(Al) distance decreased with increasing Al content. Surface analysis showed that, with increasing Al content, the content of OH groups on the mineral surface increased. The adsorption of phosphate per unit mass of Al-doped goethite increased, while adsorption per unit area decreased owing to the decrease of the relative proportion of (110) facets in the total surface area of the minerals. The results of this research facilitate better understanding of the effect of Al substitution on the structure and properties of goethite and the cycling of phosphate in the environment.  相似文献   
590.
王秀军  张健  翟磊  靖波  檀国荣 《化工环保》2016,36(4):364-369
采用红外光谱、光电子能谱、扫描电子显微镜等方法对聚合物驱油(聚驱)油田采出液处理过程中生成的两种物理性质存在明显差异的油泥(黏弹油泥和非黏弹油泥)进行组成分析及生成机理分析。实验结果表明:黏弹油泥的FTIR谱图、XPS谱图与实验室模拟生成的黏弹油泥对照样的谱图高度相似,证明黏弹油泥是聚季铵盐型清水剂与阴离子聚丙烯酰胺生成的高含油阴阳离子复合物;非黏弹油泥不含季铵盐成分,而含有酰胺和醚官能团,推测有可能来源于采出液处理剂中的聚醚成分。  相似文献   
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