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91.
油田作业废水高效处理技术中试研究 总被引:1,自引:0,他引:1
文章根据新疆油田作业废水特征及油田地处干旱区的地理特点,结合国内外含聚合物污水处理的技术现状,以及油田连续生产稳定运行的要求,在含油污水处理技术的基础上,开展了作业废水处理关键技术研究和工艺优化,采用了"隔油—絮凝气浮—深层过滤"技术。中试试验结果表明:处理后废水COD_(Cr)、石油类、SS可分别由680 mg/L、98.6 mg/L、56.2 mg/L降至98.8 mg/L、5.4 mg/L、4.5 mg/L,去除率分别为85.5%、94.5%、92.0%。 相似文献
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鼠李糖脂洗脱氯丹和灭蚁灵污染场地土壤的工艺参数 总被引:3,自引:0,他引:3
优化了鼠李糖脂洗脱氯丹、灭蚁灵污染土壤的工艺条件,为开展有机氯农药污染场地土壤洗脱修复工程实践提供科学依据和技术参数。实验结果表明,随着洗脱剂———鼠李糖脂浓度的增加,氯丹和灭蚁灵的洗脱量呈现先增加后降低的趋势;洗脱时间和液固比对洗脱效果的影响趋势与浓度相同;在0~120 r/min范围内,氯丹和灭蚁灵洗脱量随着搅拌速度的增加而增大,80、120和200 r/min的洗脱量间差异不显著;单次洗脱量随洗脱次数的增加而降低,累计洗脱量则逐渐增大。综上所述,氯丹、灭蚁灵污染场地土壤鼠李糖脂洗脱的适宜工艺参数为鼠李糖浓度10 mmol/L,搅拌速度80 r/min,固液比1∶10,洗脱时间20 min,洗脱3次。 相似文献
95.
介绍了内蒙古某抗生素废水处理厂的处理工艺流程、处理单元类型及其详细设计参数,通过对该污水处理厂半年内运行效果的调研,分析评价该污水处理系统的处理效果及出水指标;该水厂工艺流程对COD、TOC、氨氮、总氮、总磷、BOD和急性毒性的平均去除率分别为96.52%、95.83%、50.24%、55.20%、62.05%、98.52%和99.14%,COD、氨氮、总氮、总磷出水水质分别为477、438、556.7和7.69 mg/L,达到排放到城区下水道要求,园区内所有废水汇集到园区污水处理厂进行集中深度处理达标后排放水体。通过对该水厂工艺的介绍和水质分析,为我国抗生素生产企业面临的废水处理工艺类型选择及工程改造升级提供一定参考。 相似文献
96.
Temperature-dependent sorption of polycyclic aromatic hydrocarbons on natural and treated sediments 总被引:1,自引:0,他引:1
In aqueous environment temperature is considered to play a significant role in the sorption process of polycyclic aromatic hydrocarbons (PAHs) and its influence on the sorption equilibrium is indicative of sorption energies and mechanisms. In this study, sorptions of five PAHs on three heterogeneous sorbents including one river sediment (YHR), one estuary sediment (YRD) and one treated sediment with organic matter removed (IM) were carried out at a range of temperature from 5 °C to 35 °C. Stronger sorptions were observed at lower temperatures, with the equilibrium sorption coefficient Kd increasing 2-5 times as the temperature decreases 30 °C. The increase of Kd value was attributed primarily to the change of PAH water solubility, which predicted 40-75% of the increase of Kd in the sorption process. To provide insight into the sorption mechanism, enthalpy change (ΔHS) for the sorption process was calculated and the values were observed to be negative for all of the interactions, suggesting that the exothermal sorption of PAHs inversely dependents on temperature. Based on the values of ΔHS, van der Waals forces were inferred as the main sorption mechanism for the PAHs, especially on the YHR sediment which contained more organic matter. For sorption of larger size PAHs on the sorbents with low organic matter, specific interactions were deduced to contribute to the overall sorption. 相似文献
97.
利益主体视角下的西部新农合制度运行困境分析 总被引:1,自引:0,他引:1
孟宏斌 《中国人口.资源与环境》2011,21(8)
实现新农合制度设计的初衷目标、提升制度的惠农政策效果,是亟待解决的重大现实问题.为探寻制度实施效果与设计预期目标的偏差,科学厘清出影响西部新农合惠农政策效果的主要因素,本文基于西部10省区17县(区)的780份农户调研数据及相关统计数据,从医(医疗服务机构)、患(参合农民)、保(医疗保障机构)、管(政府)四方利益主体的视角,对西部新农合制度运行中的困境进行剖析.研究结果表明,既有的新农合制度运行框架模式,会陷入医疗服务机构行为扭曲与服务供给可及性差并存、医疗保障机构经办能力不足与保障效果欠佳并存、政府市场化导向与公共服务职能缺失并存、农民参合意愿强烈与被动参合并存的运行困境.三方强势主导形成的主体间利益失衡,必然影响到新农合的持续运行发展.因此,在新农合制度由试点普及向规范持续运行转轨的关键时期,必须以激励约束机制为突破,构建利益相关主体的协同联动改革机制,有效调动运行主体的积极性,实现新农合制度的持续运行. 相似文献
98.
The relationships between air pollutants, meteorological parameters and concentration of airborne fungal spores 总被引:1,自引:0,他引:1
Grinn-Gofroń A Strzelczak A Wolski T 《Environmental pollution (Barking, Essex : 1987)》2011,159(2):602-608
Fungal spores are an important component of bioaerosol and also considered to act as indicator of the level of atmospheric bio-pollution. Therefore, better understanding of these phenomena demands a detailed survey of airborne particles.The objective of this study was to examine the dependence of two the most important allergenic taxa of airborne fungi - Alternaria and Cladosporium - on meteorological parameters and air pollutant concentrations during three consecutive years (2006-2008). This study is also an attempt to create artificial neural network (ANN) forecasting models useful in the prediction of aeroallergen abundance.There were statistically significant relationships between spore concentration and environmental parameters as well as pollutants, confirmed by the Spearman’s correlation rank analysis and high performance of the ANN models obtained. The concentrations of Cladosporium and Alternaria spores can be predicted with quite good accuracy from meteorological conditions and air pollution recorded three days earlier. 相似文献
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100.
Tze-Yee Ho Fang-Ta Liu Guan-Wei Ho Yan-Ru Lin 《International Journal of Green Energy》2017,14(12):983-995
Most of the energy conversion in industrial devices and equipment is completed by the motor. The acquirement of motor parameters becomes very important for designing the motor drives. The aim of this paper is to design and implement a motor measurement system. Through the processing of an Advanced RISC Machines (ARM) microcontroller, the various parameters of motors such as input voltage, input current, input power, motor speed, and motor torque can be obtained. Consequently, the torque constant, load torque, viscous friction, and the inertia of the motor are calculated and achieved. The motor parameters can be commanded and displayed in the designed human interface of a PC via USB communication. The hardware system designed in this system includes an ARM microcontroller, an inverter, a voltage sensor, a current sensor, a torque sensor, and power supply. The software programming is developed under the Visual Studio 2012 environment development platform using the C language. Finally, the prototype of the motor measurement system is completed and verified. The experimental results for the motor parameters and torque/speed characteristic are demonstrated and show the feasibility of the complete designed system. 相似文献