三级过滤对复合型微污染地下水净化效能研究

目的研究接触氧化法的工艺过程与运行参数,以使复合型微污染地下水达到饮用水标准．方法用地下水配加MnSO4·5H2O,FeSO4·7H2O,NH4Cl和腐植酸、尿素、淀粉,模拟复合型微污染地下水,采用锰砂-陶粒-锰砂三级接触氧化过滤法处理,滤层总厚度1．5m,滤速1m／h．结果经过三级曝气、过滤后,出水主要指标达到饮用水标准．Fen氧化还原电位低,只采用跌水曝气DO值已满足要求,平均去除率为95．36％．CODMn质量浓度相对较低,在只跌水曝气时已达标,平均去除率为44．21％,增大曝气量后出水质量浓度更低,平均去除率为53．69％．采用简单的跌水曝气方式时,出水锰和氨氮质量浓度均较高,经增加曝气强度后,出水氨氮、锰逐渐开始达标,达标后平均去除率分别为97．22％和96．50％．结论三级曝气、过滤接触氧化法处理复合型微污染地下水能取得良好的净化效果,其中DO对锰和氨氮有较大影响．     

改变缺氧池容积强化A^2/O工艺脱氮除磷效率

采用实验室规模连续流厌氧-缺氧-好氧(A/A/O)工艺处理人工模拟生活污水,考察了不同碳氮比(C/N)和溶解氧(DO)工况下改变缺氧池容积对A^2/O工艺脱氮除磷效果的影响。结果表明,在低C/N和好氧阶段DO含量较低时,增大缺氧池容积有利于提高TN的去除率和除磷效率,在COD/ρ(TN)(ρ(TN)≈40 mg/L)约为7,DO的质量浓度在0.9~1.2 mg/L的条件下,缺氧池容积增加1倍,TN去除率可达71.1%,PO4^3--P去除率可达94.0%;在高C/N和好氧阶段DO含量较高时,增大缺氧池容积在提高TN去除率和改善出水水质方面效果不显著。     

一种水质监测单片机系统的软硬件开发

介绍了一种由C51单片机控制的水质在线测量系统，对该系统的控制器硬件结构进行了说明，介绍了软件的总体结构和设计方法，并分析了系统液晶显示的模块化设计。通过与传统水质测量方法的比较，说明了该系统的优越性及应用价值。     

寿光市城北污水处理厂改良型A~2/O反应池的启动与调试

寿光市城北污水处理厂一期工程处理能力为5万m3/d,以改良型A2/O反应池为核心处理单元,进水中约有60%为工业废水。改良型A2/O反应池的启动调试历时33d,调试结束时,活性污泥性状良好,CODCr、NH3—N、TP完全达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级B标准,反硝化作用明显。结果表明,在调试期间,污泥培养方式、内回流比、好氧池DO等对该污水处理厂改良型A2/O反应池处理能力影响比较明显。     

污水生物脱氮工程技术参数的探讨

对污水生物脱氮工程设计的污泥产率系数、DO、pH、系数0.47、好氧区(池)容积计算和反硝化效率等进行了探讨,以便于设计人员更好地理解<室外排水设计规范>(GB 50014-2006),不断推进我国污水处理技术的发展和标准的管理.     

DO对低C/N比污水生物亚硝化的影响分析

采用活性污泥法SBR工艺,考察DO对亚硝化的影响。首先进行195 d的连续培养试验,得出亚硝化系统DO保持在0.2 mg/L~0.6 mg/L的范围之内,可使得到有效降解且出水亚硝化率达50%~90%;然后研究系统周期内DO的变化规律,可以考虑以12 h为一个亚硝化反应周期,若延长反应时间至16 h,将使反应有向硝酸型硝化转移的趋势;最后通过烧杯试验,得出随着系统DO浓度的升高,氨氮降解率上升、亚硝化率下降,遵循DO与氨氮降解率和亚硝化率关系的数学模式。     

污水处理中基于仿人智能的DO参数控制系统

曝气控制过程中的DO（溶解氧）值是影响污水处理水质的重要参数，DO值的高低直接影响鼓风机的曝气风量。由于活性污泥法是一个复杂的生物反应过程，难以用数学模型进行准确描述，采用常规PID控制能耗大，控制品质差，一直是困扰污水处理的难题。基于控制策略的比较研究，文章提出采用HSIC（仿人智能控制）策略来解决曝气控制过程中DO值波动的控制问题，文中给出了控制规则和控制系统结构。仿真试验表明该方法控制不仅系统动、静态品质好，节能效果也很显著，说明该控制策略是可行和有效的。     

Imaging the three orientation variants of the DO22 phase by 3D atom probe microscopy

Three-phase NiAlV alloys were investigated using a three-dimensional atom probe. Ageing at 800 °C gives rise to the precipitation of two ordered phases within the supersaturated FCC solid solution, namely Ni₃Al (L1₂ structure) and Ni₃V (DO₂₂ structure). The DO₂₂ phase has three orientation variants which need to be identified in 3DAP images. It is shown that an appropriate choice of analysis site enables us to image the chemical order within both L1₂ and DO₂₂ ordered phases and to distinguish the three orientation variants of the DO₂₂ phase in reconstructed images. The lateral resolution of 3DAP in these experimental conditions was estimated through simple considerations to be less than 0.3 nm.     

FeSiAl合金薄膜电感的研制与研究

本文采用DC直流溅射的方法研制了FeSiAl合金薄膜电感,并探讨了输入功率、靶与基板间距离等溅射成形条件及成膜速率的关系及其对薄膜电感性能的影响,同时还分析了不同状态下的FeSiAl合金薄膜的结构,讨论了产生DO3超结构的最佳工艺条件。     

Effect of corrosion potential on the corrosion fatigue crack growth behaviour of low-alloy steels in high-temperature water

The low-frequency corrosion fatigue (CF) crack growth behaviour of different low-alloy reactor pressure vessel steels was characterized under simulated boiling water reactor conditions by cyclic fatigue tests with pre-cracked fracture mechanics specimens. The experiments were performed in the temperature range of 240-288 °C with different loading parameters at different electrochemical corrosion potentials (ECPs). Modern high-temperature water loops, on-line crack growth monitoring (DCPD) and fractographical analysis by SEM were used to quantify the cracking response. In this paper the effect of ECP on the CF crack growth behaviour is discussed and compared with the crack growth model of General Electric (GE). The ECP mainly affected the transition from fast (‘high-sulphur’) to slow (‘low-sulphur’) CF crack growth, which appeared as critical frequencies ν_crit = f(ΔK, R, ECP) and ΔK-thresholds ΔK_EAC = f(ν, R, ECP) in the cycle-based form and as a critical air fatigue crack growth rate da/dt_Air,crit in the time-domain form. The critical crack growth rates, frequencies, and ΔK_EAC-thresholds were shifted to lower values with increasing ECP. The CF crack growth rates of all materials were conservatively covered by the ‘high-sulphur’ CF line of the GE-model for all investigated temperatures and frequencies. Under most system conditions, the model seems to reasonably well predict the experimentally observed parameter trends. Only under highly oxidizing conditions (ECP ? 0 mV_SHE) and slow strain rates/low loading frequencies the GE-model does not conservatively cover the experimentally gathered crack growth rate data. Based on the GE-model and the observed cracking behaviour a simple time-domain superposition-model could be used to develop improved reference CF crack growth curves for codes.