厌氧颗粒污泥流化床的动力学参数测定

介绍了厌氧颗粒污泥流化床反应器的主要动力学参数及其测定方法。通过分批试验测定厌氧动力学系数,以基质代谢平衡方程计算得到颗粒污泥双膜模型中的产甲烷层厚度,进行了颗粒污泥粒径、干密度等的测定和扩散系数的确定。以这些参数为基础的动力学模型计算结果与反应器长期连续运行测定结果相一致,证明了所测参数及其模型的可靠性。      

紫外线消毒系统中强度分布的理论计算与生物验证对比

应用以MPSS模型为基础的计算软件UV calc对某饮用水紫外线消毒反应器进行强度分布的计算,同时,采用枯草芽孢杆菌(ATCC9372)作为受试菌种进行生物验证.结果显示,在该反应器中理论计算数值总体上明显高于生物验证的数值,反应器中最低紫外剂量区域出现在2支灯管之间的反应器壁附近.另外,理论计算和生物验证的误差与流量、透光率具有相关性.在高流量、低透光率的情况下,理论计算的数值更接近于生物验证数值.相对于理论计算,生物验证是确定紫外线反应器剂量反应曲线的可靠方法.     

运用活性污泥一号模型对缺氧——好氧生物废水处理工艺的模拟

随着污水生物处理技术的进步,很多相关的数学模型被开发出来用以描述污水生物处理工艺的机理,并指导其设计和运行管理.最为著名和应用广泛的当属国际水质协会(IAWQ)推出的活性污泥数学模型系列(Activated Sludge Model 1～3),即ASM模型.通过以反应器动力学为基础,使用活性污泥一号模型(ASM1)对缺氧-好氧生物废水处理工艺建立数学模型并且加以模拟的结果,得出了在不同的工况参数和反应条件(分别是污泥龄,缺氧池与好氧池的体积比,回流和内回流)下各级反应器中污染物质(主要是可溶性有机污染物,氨氮和硝态氮)浓度的变化规律,可以为实际工艺的设计与运行提供参考和依据.     

环境工程中生物反应器的研究

生物反应器是以微生物的降解作用为基础的污染控制装置,主要依靠的是微生物对污染物的催化作用,然后借助反应器装置为载体,充分发挥微生物的优势。本文介绍了生物反应器的分类,工作原理和特点,指出生物反应器的特征和基本功能。此外,对常见的生物反应器的特征和用途进行介绍,并指出生物反应的应用领域、优势等。     

厌氧颗粒污泥流化床降解有机物的动力学分析

在前人研究的基础上,运用反应器理论,建立了厌氧颗粒污泥流化床反应器内有机物降解的动力学模型,在测定动力学模型参数的基础上,以大量实验资料验证了模型及其假设的可靠性,并对反应器效率进行了模拟分析。结果表明,在本试验条件下的最佳颗粒污泥粒径为０．８２ｍｍ,反应器最佳生物浓度为５０ｇ／Ｌ。     

基于柱状发光体悬浆式光催化反应器绝对量子产率的计算方法

与均相体系不同 ,多相光催化体系不能忽略催化剂颗粒对光子的散射 ,但严格求解光辐射传递方程在数学上是很困难的 .通常采用的输入光强计算表观量子产率的方法往往低估了真实的光量子产率 .本文针对带有柱状发光体圆筒形悬浆体系反应器 ,在做出一些合理的简化后 ,提出了一种以二氧化钛为催化剂在近紫外光辐照下多相光催化绝对量子产率的计算方法 .以苯酚为模型化合物 ,应用在典型反应器中光催化降解的实验结果 ,求得局域体积光子吸收速率 (LVRPA)在反应器内的分布 ,计算了绝对光量子产率 .表观量子产率与绝对量子产率相差7.08% ,约有1.1%输入光辐射从反应器筒壁上被淬灭 .本方法可用来评价不同催化剂或同一催化剂不同模型化合物的光催化效率 ,也为光催化反应器的设计提供了依据 .     

模拟酸雨条件下垃圾填埋的重金属地球化学迁移模型——以徐州为例

为研究酸雨沉降条件下垃圾中重金属迁移过程,以重金属浓度变化为基础,建立了生物反应器填埋场重金属浸出和淋出的地球化学迁移过程模型和地球化学迁移的数学预测模型。研究表明,重金属的浸出顺序为As、Ni、Cr、Co、Cd、Mn、Cu、Zn、Sn、Hg、Pb、Fe,淋出顺序为Mn、Co、Ni、Cr、Cu、Cd、As、Fe、Zn、Hg、Pb、Sn;对生活垃圾重金属浸出所建立的数学模型大多为指数函数、幂函数、二次函数,对模拟酸雨条件下的生物反应器填埋场重金属的淋出建立的数学模型大多为二次函数、幂函数,数学模型的相关系数在0.9以上,模型拟合效果较为理想;通过引进重金属元素释放系数建立了生物反应器填埋场重金属淋出累积总量的模型,修正后的模型的计算结果和实测值的误差在千分之一以内,可用于预测填埋场内重金属溶出总量。     

A/O法活性污泥系统计算机模拟研究

介绍了以活性污泥 1号模型 (ASM1 )和固体通量沉淀模型为基础 ,结合反应器原理 ,用VB6 .0计算机语言建立A/O法活性污泥模拟器的方法 ,探讨了A/O法活性污泥系统的模拟工艺流程、各组分的物料平衡关系和欧拉法数值积分的步长选取等问题。模拟器的校准结果表明 ,该模拟器建立的思路和方法完全正确 ,可以用于A/O法活性污泥系统的模拟和预测。     

一般性问题

X701 200501526 生物法处理挥发性有机废气的研究/饶佳家…(重庆大学生物工程学院生物力学与组织工程教育部重点实验室)//环境污染治理技术与设备/中科院生态环境研究中心.-2004,5(9).-56-60 环图X-4 生物法处理被污染的空气这一技术已经被德国和荷兰成功地运用了20年之久,但是在国内还属于一种较新的空气污染治理技术。本文主要概述了有机废气生物处理的3种主要形式:生物滤池、生物滴滤塔和生物洗涤器的原理、流程和几种影响反应器性能的因素,并比较了以上3种反应器及其不同支撑材料的优缺点。目前,气态生物反应器主要以通用的指导方针、试验性的研究和来自类似应用的经验为基础进行设计的。图4表2参23     

城市污水厌氧处理技术研究进展

通过介绍厌氧处理技术在城市污水处理中的现状及研究焦点,论述了以微生物固定化和提高污泥与污水混合效率为基础的一系列高速厌氧反应器的特点,分别阐述了升流式厌氧污泥床、折流式厌氧反应器、内循环厌氧反应器及颗粒污泥膨胀床反应器的研究进展,提出高效率的厌氧处理系统应满足的条件,并与好氧处理技术作了对比,综述了新型反应器的研制及其组合工艺的应用在废水处理领域所发挥的重要作用.     

配水管网中与有机物反应的余氯衰减动力学模型

提出一级二级反应组合动力学模型,用大量实验数据拟合模型中的参数,模拟配水管网系统中余氯衰减的水体消耗部分.该模型定量反应了温度T、初始氯浓度c₀和TOC与余氯衰减之间的复杂关系.除初始阶段外,组合模型可简化为一级反应模型;T、TOC和c₀与余氯衰减之间的关系分别可简化为指数关系、正线性关系和负线性关系.该模型较好地解释了余氯衰减在初始阶段进行相对较快这一现象.实验数据验证的结果表明:该组合模型与实验数据吻合良好,优于传统的一级反应模型.     

Two-dimensional numerical and eco-toxicological modeling of chemical spills

The effects of chemical spills on aquatic nontarget organisms were evaluated in this study. Based on a review of three types of current eco-toxicological models of chemicals, i.e., ACQUATOX model of the US-EPA, Hudson River Model of PCBs, and critical body residual (CBR) model and dynamic energy budget (DEBtox) model, this paper presents an uncoupled numerical ecotoxicological model. The transport and transformation of spilled chemicals were simulated by a chemical transport model (including flow and sediment transport), and the mortalities of an organism caused by the chemicals were simulated by the extended threshold damage model, separately. Due to extreme scarcity of data, this model was applied to two hypothetical cases of chemical spills happening upstream of a lake. Theoretical analysis and simulated results indicated that this model is capable of reasonably predicting the acute effects of chemical spills on aquatic ecosystems or organism killings.     

单轴虚拟振动试验技术研究

目的 探索结合有限元和闭环随机振动控制方法搭建的随机振动虚拟试验系统是否可信,以及其限制条件,并明确下一步的工作方向。方法 搭建虚拟振动,并获得虚拟试验结果,并和实物试验结果进行比对。分别搭建随机振动控制仪模型和振动系统有限元模型,再组合成整个闭环随机振动虚拟试验系统。对振动台、夹具、产品进行有限元建模后,再根据模态试验结果对其修正。振动台、夹具、产品的有限元模型修改到位后,组合成振动系统有限元模型,振动系统有限元模型联合控制仪模型,构建闭环随机振动虚拟试验系统,并将虚拟试验结果和实物试验结果进行比对。结果 在400 Hz之前的低频段,虚拟试验结果和实物试验结果的一致性较好。结论 这种方法搭建的虚拟振动系统,在400 Hz前的低频段,可信度较好。     

Relationship between PM10 and PM2.5 levels in high-traffic area determined using path analysis and linear regression

The objective of this study was to determine the relationship between PM_(10) and PM_(2.5) levels as related to meteorological conditions and traffic flow using both a linear regression analysis and a path analysis. The Particulate matter(PM) samples were collected from Sukhumvit road, Bangkok, Thailand, at both open(104 samples) and covered(92 samples)areas along the road. Fifteen percent of all samples were separated before the statistical models were run and used for model validation. The results from the path analysis were more elaborate than those from the linear regression, thus indicating that meteorological conditions had a direct effect on the particulate levels and that the effects of traffic flow were more variable in open areas. The model also indicated that meteorological conditions had an indirect effect and that traffic flow had a direct effect on particulate levels in covered areas. The model validation results indicated that for open areas, the R~2 values were not very different between the path analysis and the linear regression model, but that the path analysis was more accurate than the linear regression model at very low PM concentrations. At high PM concentrations, the path analysis model also had a better fit than did the linear regression, so the predictions from the path analysis model were more accurate than those from the linear regression.     

Reconciling model results with user needs to improve climate policy

The aim of this study is to understand the ‘reconciliation process’ between model results and user needs in Participatory Integrated Assessments. This process is analyzed for the Delft Dialogue, a project in which scientists and UNFCCC delegates used the IMAGE model to assess the consequences of different climate policy proposals. The Delft Dialogue consisted of five iterations in which model results were presented and requests for new analyses were prioritized. These requests were diverse, changed over time and linked long-term model projections with short-term policy targets. We conclude that two factors played an essential role in the reconciliation process in the Delft Dialogue: (1) user requests were identified in iterative interactions and guided the selection of model analyses and (2) model analyses were co-produced by participants and modelers. This Dialogue shows that reconciliation processes can be facilitated through a transparent, interactive and iterative process where user needs are elicited to guide the choice for model analyses.     

自然资源核算的生态足迹模型演进及其评论

生态足迹模型作为从生态角度对自然资源进行核算的方法,其发展经历了从一维模型向二维模型,并从二维模型向三维模型的演进过程,论文从科学问题、模型内涵、应用指向和解释能力等4个方面对生态足迹模型演进作了梳理和评论。研究结果表明：1）生态足迹模型是自然资源核算的一个生物物理性工具,弥补了主流的国民经济核算体系下自然资源价值核算的不足。2）一维模型开创性地引入生态生产性土地概念开展自然资源消费核算,以此来测算人类活动对生态的占用情况;二维模型在自然资源消费核算维度的基础上,引入自然资源生态承载能力维度,开拓了自然资源承载力评价的新视野;三维模型进一步从流量和存量两个维度理解自然资源生态承载能力,以圆柱体体积表达生态足迹,生动刻画人类活动对所处区域的生态压力。3）一维模型是二维、三维模型的基础,但它们解决的科学问题各有不同,从而所适用的研究尺度、应用指向也有所差异。4）生态足迹模型属于静态分析模型,无法解释生态经济社会系统的动态变化情况;二维和三维模型属于封闭模型,其计算结果不能准确反映区域生态的真实状况。最后,探讨了生态足迹模型进一步优化的方向。     

基于RF-LSTM的鸡舍恶臭气体预测研究

以鸡舍氨气为研究对象,对鸡舍氨气预测模型进行了研究.首先,利用随机森林算法（RF）对影响鸡舍氨气浓度的环境变量进行重要性排序,选取温度、湿度、光照、气象温度、降雨量作为模型的输入变量;在此基础上,构建了基于长短时记忆神经网络（LSTM）的鸡舍氨气浓度预测模型,并将提出的预测模型应用于江苏省宜兴市某养鸡场的氨气浓度预测中,并与LSTM模型、RF-Elman模型和RF-BP模型进行了对比实验,结果表明,基于RF-LSTM模型的预测效果最好,其平均绝对误差（MAE）、平均绝对百分误差（MAPE）和均方根误差（RMSE）分别为0.9183、4.9637%和1.4262;同时,为了验证该模型的性能,本文还实现了不同时间尺度的鸡舍氨气浓度预测,提前2h、3h、4h、5h氨气预测的平均绝对误差（MAE）分别为1.6218、2.1991、2.8553和3.0677.本文提出的预测模型提高了鸡舍氨气浓度的预测精度,可为减少鸡舍恶臭气体排放提供科学依据.     

A vertically integrated eutrophication model and its application to a river-style reservoir-Fuchunjiang,China

Based on a 2-D hydrodynamic model, a vertically integrated eutrophication model was developed. The physical sub-model can be used for calculation of water density at different depths and the water quality sub-model was for calculation of algal growth. Suspended solids were divided into two types of sediment which named cohesive and non-cohesive sediments and simulated using separate methods. The light extinction coefficient used in the underwater light regime sub-model was linearly related to the sum of sediment and phytoplankton biomass. Some components less important to the model were simplified to improve practicability and calculation efficiency. Using field data from Fuchunjiang Reservoir, we calculated the sensitivity of ecological parameters included in this model and validated the model. The results of sensitivity analysis showed that the parameters strongly influenced the phytoplankton biomass including phytoplankton maximum growth rate, respiration rate, non-predatory mortality rate, and settling rate, zooplankton maximum filtration rate, specific extinction coefficient for suspended solids and sediment oxygen demand rate. The model was calibrated by adjusting these parameters. Total chlorophyll a (chl-a) concentrations at different layers in the water column were reproduced very well by the model simulations. The simulated chl-a values were positively correlated to the measured values with Pearson correlation coefficient of 0.92. The mean difference between measured and simulated chl-a concentrations was 12% of the measured chl-a concentration. Measured and simulated DO concentrations were also positively correlated (r=0.74) and the mean difference was 4% of measured DO concentrations. The successful validation of model indicated that it would be very useful in water quality management and algal bloom prediction in Fuchunjiang Reservoir and a good tool for water quality regularation in other river-style reservoirs.     

战场电磁兼容预测中的接收机建模研究

目的建立战场电磁兼容预测分析的接收机数学模型,包括接收机频率选择性模型、敏感度门限模型、互调模型及与接收机有关的修正系数计算模型等。方法在分析接收机干扰类型的基础上,建立上述数学模型,并探讨模型中的参数获取方法。结果给出了频率选择性模型分段折线斜率常数的获取方法,并对相关的互调系数、保护比等重要参数的实验测量方法进行了分析。结论建模结果可支持战场电磁接收装备仿真,为战场电磁兼容预测分析奠定基础。     

旋风分离器内流场的数值模拟及方法分析

基于交错网格的SIMPLE方法对切向入口旋风分离器内的流场进行了数值模拟 ,为了分析验证不同湍流模型的适用效果 ,分别选用了标准的k -ε模型、Smith修正的模型和Chen Kim修正的模型。通过对同一工况模拟结果与实验数据的比较 ,发现Smith修正的湍流模型更适合于预报像旋风分离器内这种具有返转流动的强旋流场