周边进水辐流式沉淀池配水均匀性的设计探讨

在此从周边进水辐流式沉淀池配水槽内水力学的角度分别介绍了等水深和等渠宽两种配水方式的计算方法,分析了各自的工艺特点,以工程实用为原则,并结合工程实例得出等宽度变孔距法能较好地实现均匀配水。并从配水槽内能量微分方程的角度分析了变孔距法的配水均匀性和稳定性。     

饲料中新型持久性有机污染物分析方法与污染特征研究进展

饲料是养殖动物的主要食物来源,饲料中的持久性有机污染物(POPs)能够在养殖动物体内蓄积,从而影响动物源性食品安全,对人体健康构成潜在的危害.目前有关饲料中二英类等传统POPs的研究已较为深入,而饲料中新型POPs的污染也逐渐引起人们的关注.本文综述了现有文献关于饲料中多溴二苯醚(PBDEs)、六溴环十二烷(HBCD...     

Macroscale and microscale analysis of Anammox in anaerobic rotating biological contactor

Inoculated with conventional anaerobic activated sludge, the Anammox process was successfully developed in an anaerobic rotating biological contactor (AnRBC) fed with a low ratio of C/N synthetic wastewater. Operated in a single point feed mode, the AnRBC removed 92.1% (n = 126) of the influent N at the highest surface load of 12 g/(m².day). The biomass increased by 25% and 17.1 g/(m².day) of maximum N removal surface load was achieved by elevating flow rate with another feed point. Fluorescence in situ hybridization and polymerase chain reaction analysis indicated that the Anammox genus Candidatus Kuenenia stuttgartiensis dominated the community. Both Anammox and denitrifying activity were detected in biofilm by the application of microelectrodes. In the outer layer of the biofilm (0-2500 μupm), nitrite and ammonium consumed simultaneously in a ratio of 1.12/1, revealing the occurrence of Anammox. In the inner layer (> 2500 μupm), a decrease of nitrate was caused by denitrification in the absence of nitrite and ammonium.     

NF和低压RO工艺处理锅炉补给水的研究

以自来水为原水,采用纳滤(NF)与低压反渗透(RO)工艺进行锅炉补给水处理研究。考察了一级NF及RO工艺、二级NF及RO工艺、NF-RO串联和RO-NF串联工艺对锅炉补给水的软化除盐效果。结果表明,NF和RO分别在0.75MPa和1.0Mpa压力下,回收率20%时处理效果最好。一级NF和一级RO可满足中低压热水锅炉补给水的水质要求;二级NF和二级RO、NF-RO和RO-NF工艺均可满足中低压蒸汽锅炉补给水的水质要求;串联工艺处理效果优于二级NF,且比二级RO节能;RO-NF和二级RO工艺可满足高压锅炉补给水的水质要求。     

深度处理后污水用于锅炉补水的可行性研究

在污水处理场,经过生化处理后的排放水中仍含有一定的悬浮物、氨、氮、油、菌类及大量的溶解盐类,其COD也较高,因而不能直接用于锅炉补水。用“斜板沉降-连续过滤-超滤-反渗透”这一组合工艺来处理炼油污水,并将处理后的污水回用于锅炉补水。对其可行性进行了科学的分析和论述,并进行了中试。试验证明,该工艺流程及设备无论在技术上还是在经济上都是可行的。     

Effects of operational factors on soluble microbial products in a carrier anaerobic ba ed reactor treating dilute wastewater

The effects of feed strength, hydraulic residence time （HRT）, and operational temperatures on soluble microbial product （SMP） production were investigated, to gain insights into the production mechanism. A carrier anaerobic baffled reactor （CABR） treating dilute wastewater was operated under a wide range of operational conditions, namely, feed strengths of 300-600 mg/L, HRTs of 9- 18 h, and temperatures of 10-28℃. Generally, SMP production increased with increasing feed strength and decreasing temperature. At high temperature （28℃）, SMP production increased with decreasing HRT. As the temperature was decreased to 18 and 10℃, the SMP production was at its peak for 12 h HRT. Therefore, temperature could be an important determinant of SMP production along with HRT. A higher SMP to soluble chemical oxygen demand （SCOD） ratio was found at high temperature and long HRT because of complete volatile fatty acid degradation. SMP accounted for 50%-75% of the SCOD in the last chamber of the CABR. As a secondary metabolite, some SMP could be consumed at lower feed strength.     

苯硝化工艺HAZOP分析的定量化研究

为提高危险化工工艺过程风险评估的准确性,通过工艺仿真模拟,研究工艺参数波动对生产装置安全性能的影响。以苯硝化工艺为例,采用危险与可操作性分析对该过程进行定性的风险评估;同时利用Aspen Plus建立苯硝化装置的模拟流程。结合HAZOP分析中偏差与模拟中硝化釜的流程变量之间的联系,以进料混酸的流量和1号硝化釜热负荷及出口温度为量化指标,观察混酸流量在正常操作点17.6 m3/h的±100%范围波动下1号硝化釜热负荷及出口温度的变化。研究结果表明,保持1号硝化釜温度为正常值,随着混酸流量的增大,硝化釜热负荷先增大后减小;保持硝化釜热负荷不变,随着混酸流量的增大,硝化釜温度先增大后减小。其中混酸流量值超过22.95 m3/h时,温度超过报警阈值60℃。     

变频调速技术对锅炉给水泵安全运行的影响

分析给水泵变频调速节能原理;针对锅炉给水泵改由变频器控制后存在的汽蚀及平衡盘磨损等问题进行了深入的研究,并提出了解决办法.     

半焦脱硫剂的制备及其H2S脱除性能

利用废弃褐煤半焦原料作为炭基材料前驱体,经表面改性处理后制备高效脱硫剂,用于脱除原料气中的少量H2S杂质.经改性处理后,改性半焦的比表面积显著提高,形成丰富的织网结构,灰分和挥发分减少,固定碳含量增加,表面酸/碱性官能团含量也随着改性处理过程发生明显变化.采用固定床反应器和模拟气体考察脱硫剂的脱硫性能,结果表明,原料褐煤半焦基本没有脱除H2S的能力.改性处理后,随着改性半焦物化性质的改善,脱硫能力迅速提高穿透时间达95 min.负载铁氧化物有利于进一步增强其脱硫性能,穿透时间提高到1095 min;温度、氧含量和水含量等因素对脱硫性能的影响也非常显著.     

饵料对稀有鮈鲫幼鱼和成鱼生长的影响及摄食优化策略研究

在实验室适宜的饲养条件下,进行不同发育阶段的稀有鮈鲫为期30 d的摄食-生长实验,研究3种饵料在投喂量分别为鱼体湿重的3.0%、4.0%和6.0%的3种摄食水平条件下,对稀有鮈鲫幼鱼(初始湿重为(0.0749±0.02)g)和成鱼(初始湿重为(0.2603±0.06)g)的生长影响。结果表明,不同摄食水平组的稀有鮈鲫幼鱼的相对增重率和特定生长率随摄食水平的增加而增加,但饲料转化率呈下降趋势;而稀有鮈鲫成鱼的相对增重率、特定生长率和饲料转化率的变化趋势基本相同。适宜摄食水平随稀有鮈鲫体重的增加而降低,稀有鮈鲫幼鱼和成鱼的适宜饵料分别为O.S.I.微细颗粒和O.S.I.细颗粒,适宜摄食水平分别为6.0%和4.0%。