Modeling of a sequencing batch reactor treating municipal wastewater using multi-layer perceptron and radial basis function artificial neural networks

A sequencing batch reactor was modeled using multi-layer perceptron and radial basis function artificial neural networks (MLPANN and RBFANN). Then, the effects of influent concentration (IC), filling time (FT), reaction time (RT), aeration intensity (AI), SRT and MLVSS concentration were examined on the effluent concentrations of TSS, TP, COD and NH₄⁺-N. The results showed that the optimal removal efficiencies would be obtained at FT of 1 h, RT of 6 h, aeration intensity of 0.88 m³/min and SRT of 30 days. In addition, COD and TSS removal efficiencies decreased and TP and NH₄⁺-N removal efficiencies did not change significantly with increases of influent concentration. The TSS, TP, COD and NH₄⁺-N removal efficiencies were 86%, 79%, 94% and 93%, respectively. The training procedures of all contaminants were highly collaborated for both RBFANN and MLPANN models. The results of training and testing data sets showed an almost perfect match between the experimental and the simulated effluent of TSS, TP, COD and NH₄⁺-N. The results indicated that with low experimental values of input data to train ANNs the MLPANN models compared to RBFANN models are more precise due to their higher coefficient of determination (R²) and lower root mean squared errors (RMSE) values.     

论岩浆的逆向演化及其成矿作用

长江中下游的岩浆岩在某些地区表现为由酸性→中性→基性的演化顺序,我们称之为岩浆的逆向演化.本文讨论了岩浆逆向演化的地质、地球化学背景及其产生机制,同时也论证了岩浆逆向演化与内生成矿作用的关系.     

单级与两级序批式反应器用于牛场污水处理的比较研究

对序批式反应器 (SBR)的特点进行了简要的介绍。研究了水力停留时间和有机负荷率对单级和两级SBR用于牛场污水处理时污染物去除率和出水水质的影响 ,并对单级和两级SBR的污水处理性能进行了比较。研究结果表明 ,当用单级SBR处理 10 0 0 0mg LCODCr的污水时 ,1d水力停留时间即可获得较好的处理效果 ,但出水中仍含有一定量的氨。两级SBR可使用较短的水力停留时间而获得较高的污染物去除率和较好的出水水质 ,并可通过硝化过程实现氨的完全的去除     

STC脉冲喷吹袋式除尘器在机立窑烟气除尘脱硫中的应用

介绍了STC脉冲喷吹袋式除尘器的自动控温、外滤除尘、自控离线脉冲喷吹清灰的工作原理和特点 ,监测数据说明该除尘器成功解决了机立窑消烟、除尘和脱硫问题     

多级环流曝气技术处理工业污水的实验研究

在结构简单、占地面积小、氧利用率高的多级环流曝气小型实验装置上，对某种石油化工排放污水进行了生化处理性能实验。分别利用间歇和连续两种装置进行污水的处理，均得到了良好的试验结果。间歇实验探索了污水降解与系统中溶解氧的变化情况的对比，摸索出了两者之间的初步关系。连续实验表明，污水的停留时间在3-5h时，出水COD可以降到80mg／L以下。     

Fulvic acid removal by nanoparticle TiO2 using a submerged membrane photocatalysis reactor

The degradation of fulvic acid（FA） by nanoparticle TiO2 in a submerged membrane photocatalysis（SMPC） reactor was studied. In this reactor, photocatalytic oxidation and membrane separation co-occured. The continuous air supplier provided O2 for the photocatalytical reaction and mixed the solution through an airflow controller. The particle TiO2 could automatically settle due to gravity without particle agglomeration so it could be easily separated by microfiltration（MF） membrane. It was efficient to maintain high flux of membranes. The effects of operational parameters on the photocatalytic oxidation rate of FA were investigated. Results indicated that photocatalyst at 0.5 g/L and airflow at 0.06 m^3/h were the optimum condition for the removal of fulvic acid, the removal efficiency was higher in acid media than that in alkaline media. The effects of different filtration duration on permeate flux rate of MF with P25 powder and with nanoparticle TiO2 were compared. Experimental results indicated that the permeate flux rate of MF was improved and the membrane fouling phenomenon was reduced with the addition of nanoparticle TiO2 catalyst compared with conventional P25 powder. Therefore, this submerged membrane photocatalysis reactor can faciliate potential application of photocatalytic oxidation process in drinking water treatment.     

直接法测定大气中的非甲烷烃

介绍了在２个监测点，用直接法测定大气中的非甲烷烃。测定方法的检出限可达０．００６５ｍｇ／ｍ＾３，在线性范围０－１０ｍｇ／ｍ＾３时，线性相关系数为０．９９９５，相对标准焦虑差为２．８％。结果表明，由于大气逆温层、工业排放源、汽车排气对非甲烷烃的浓度变化产生影响，其日变化曲线呈双峰形。     

TiO_2光催化剂固定化技术及光催化反应器研究

从TiO2光催化剂的固定化技术和分类以及光催化反应器的研究进展状况方面进行了综述,指出存在的问题并提出改进方法。     

2500 m3多级内循环(MIC)厌氧反应器在柠檬酸废水处理工程中的应用

MIC反应器是在UASB反应器的基础上发展起来的第三代厌氧反应器,它具有效率高、能耗低、投资少、占地省等优点。作者所在单位自行研制、安装、调试的生产规模2500m3MIC反应器用于处理高浓度柠檬酸生产废水,经过两年多的启动和实际运行,在水力停留时间12.5h,COD有机负荷12kg·m-3·d-1时,COD去除率仍始终在90%左右。     

污水处理的新技术与新发展

介绍我国对水污染控制认识的发展和深化，阐述了污水生物处理方面的研究和新进展，包括在微生物方面的研究和新反应器、新工艺的发展。同时，讨论了新型、高效化学混凝剂和絮凝剂的开发成功，使化学法用于城市污水的处理成为可能。并提出任何一种新的处理工艺和反应器都各有其优缺点和适用条件，不能认为某一种就是最好，最先进的，可以无条件适用各种情况的。