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.     

矿物材料吸附去除污水中磷的试验研究

采用粉煤灰、高岭土、泥渣(取电厂澄清池排泥作脱水干燥处理)作为吸附剂深度处理污水中的磷,对比分析了3种吸附剂的吸附速度、吸附性能及除磷效果。结果表明:粉煤灰和高岭土用时20 min完成对磷的有效吸附,沉降泥渣用时5 min即可实现同等吸附效果;沉降泥渣对污水中磷的吸附能力较好,投加量为0.2 g/L的泥渣对磷的去除率可达98.1%,而投加量为0.2 g/L粉煤灰或高岭土对磷的去除率仅达到77.2%。     

Relationship between physicochemical properties and dewaterability of hydrothermal sludge derived from different source

Sewage sludge (SS) and deinking sludge (DS) were used to comparatively study the hydrothermal dewatering of sludge with different components. For a better overview, an insight into the relationship between physicochemical properties and dewaterability of hydrothermal sludge was provided. Results found that not all kinds of sludge were suitably conditioned by hydrothermal treatment (HT) in term of the elevation of dewaterability. Higher hydrothermal temperature tended to enhance the dewaterability of SS rather than DS, which was supported by the variation of their physicochemical properties (including water distribution, bonding energy, extracellular polymeric substance (EPS), particles size, acid functional groups and zeta potential in this study). In addition, the changes in surface morphology suggested that the reverse effect of HT on sludge dewaterability was mainly due to their dewatering behavior. For SS, the destruction of EPS structure leaded to the release of bound water, thereby strengthening sludge dewatering. Conversely, “Bridging effect” generated by lignocellulose in DS was beneficial for sludge dewatering; however, the increasing hydrothermal temperature degraded part of lignocellulose and weakened “bridging effect”, finally resulting in worse dewaterability of DS.     

城市生活垃圾理化性质的动态特性分析

对太原市城市生活垃圾的组成、化学元素及重金属等进行了1年(每月2次)共24次的分析。结果表明,太原市生活垃圾的组成在焚烧过程中,能产生低位热值(Q低)的有机物占(44.28±2.24)％,不产生低位热值的无机物占(13.94±2.01)％,混合物(破碎的动植物碎片及粘附在其上面的灰、土、砂)占(43.36±8.67)％。垃圾中可燃物比例较高,水分含量较低,有利于焚烧和热解,低位热值(Q低)平均值为(5590.8±1252.3)kJ/kg,但低位热值随季节变化较大。垃圾中化学元素硫(S)、氯(Cl)、氮(N)、氢(H)、碳(C)、氧(O)的年平均值分别为(0.20±0.13)％、(0.48±0.11)％、(0.87±0.18)％、(2.56±0.76)％、(30.78±4.06)％、(16.42±5.17)％,与其他城市相比,S、N、Cl的含量较高。垃圾中的重金属铅(Pb)、镉(Cd)的年平均值分别为41.94mg/Kg和1.806mg/kg;汞(Hg)含量变化较大。焚烧后的灰渣中,Pb部分挥发,Cd得到富集,但几乎无Hg检出。     

SBR法处理中药材有机废水工艺研究

应用ＳＢＲ法对中药材有机废水进行了研究。考察了ＣＯＤＣＲ、ＢＯＤ５、ＳＳ、ＮＨ３－Ｈ的处理效果，以及ＰＨ、水温、污泥负荷等条件对去除率的影响。运行结果表明，ＰＨＯ ６．０－９．０、ｔ为１５－３０℃、污沁荷０．３ｋｇＢＯＤ５／ｋｇＭＬＳＳ．ｄ，运行程序：进水０．５ｈ（限制曝气）、曝气１０ｈ、脱氮１．５ｈ，沉降０．５ｈ，排水０．５ｈ、闲置１１ｈ，周期时间２４ｈ时ＣＯＤＣＲ去除率８８％、ＢＯＤ５９４％、     

ASM1中废水和污泥组分浓度的测定方法研究

对呼吸计量法应用于校准ASM1作了简明的阐述。在呼吸速率与模型组分关系的基础上,介绍了ASM1中废水与污泥各组分浓度的测定方法,并指出模型组分细化的意义。     

污泥综合处理技术系统的可行性分析

通过对污泥处理技术现状与污泥组成的分析，认为降低污泥的含水率是改善污泥可处理性的关键。以机械脱水加工热干燥过程可达到充分降低污泥含水率的目的。以此为主干所形成的污泥综合处理系统经能量与经济平衡分析，发现其能量输出大于输入，经济成本合理，有一定的技术经济可行性。     

塑料和橡胶类废物的热物理与焚烧特性研究的进展

随着社会和科技的发展，塑料和橡胶废弃量与日俱增，已成为城市垃圾的重要组成，由于这类废弃的聚合物给环境带来了污染问题，怎样合理地处理和利用已经成为一项重要的研究课题，本文对塑料和橡胶类的废物的理化性质，热值，焚烧特性，污染特性进行了论述，并根据它们的热物理及焚烧特性提出了进一步优化废物焚烧炉，完善低污染，低腐蚀，低粘结的废弃物的焚烧工艺的一些设想。     

城镇污水资源化技术发展状况

污水资源化是解决当前水资源短缺，减少环境污染的有效途径，经过几十年的发展，城镇污水资源化技术取得了很大进展，讨论了城镇污水资源化的意义、技术和发展前景。     

重庆市城市污水厂污泥的处理与处置

分析了目前重庆市城市污水厂污泥的处理与处置现状 ,对今后重庆市城市污水厂污泥的管理进行了探讨 ,提出了几个应注意的问题。