复合生物滤池+潜流人工湿地组合工艺处理农村生活污水

针对农村生活污水水质水量不稳定,低碳氮比,运行费用不足等特点,探讨了复合生物滤池+潜流人工湿地组合工艺处理农村生活污水的实用性。其结果显示,虽然进水水质水量波动大,但出水水质稳定、去除效果良好,达到《城镇污水处理厂污染物排放标准》(GB18918-2002)一级B标准,且运行费用低、低能耗,操作及维护简单,较适用于农村生活污水的处理。     

城市污水处理厂进水规律表征与模型校核

进水水量水质的负荷变化是影响污水处理厂运行调控的重要因素。污水处理厂的进水特性时刻在变化,但从长期来看,其存在一定的变化规律。为研究污水处理厂进水规律,并探究建立对应水质水量预测模型的方法,分析了季节、天气及日类型对大渡口污水处理厂进水各指标的影响,在此基础上构建进水数学模型,并引入校核系数η对水量、COD、BOD5、TN、NH+4-N和TP等参数进行校核,校核后各参数的模拟值与实测值相关性系数分别为80.6%~85.4%(2008年),83.3%~87.3%(2009年)。研究结果可为污水处理系统计算机仿真和调控策略研究提供数据基础。     

中型污水处理厂中药物和个人护理品的分布与去除

为了解15种药物及个人护理用品(PPCPs)在中小型污水处理厂中的分布及其去除效果,采用液相色谱-串联质谱(LC-MS/MS)技术对3座A2/O工艺的污水处理厂水样进行分析研究。结果显示,除普萘洛尔、吉非罗平和吲哚美辛在3座中小型污水处理厂各个工艺单元中均未被检出外,其余12种目标化合物的检出频率在90%~100%之间。进水水样中PPCPs的平均检出浓度为2 285.4 ng/L,其中咖啡因(CF)的平均检出浓度最高为973.3 ng/L,酮洛芬(KP)的平均检出浓度次之为844.7 ng/L,两者之和占进水水样中PPCPs平均含量的79.5%,表明污水处理厂的主要污染物为CF和KP。3座污水处理厂对CF的去除效果最为显著,平均去除率为95.3%,对15种PPCPs总去除效率在39.3%~82.8%之间。     

淄博市某城市污水处理厂运行效果分析

淄博市是我国重要的石油化工基地,工业废水与生活污水多混合排放到城市污水处理厂处理,污水成分复杂,处理难度大。根据淄博市某污水处理厂的长期运行数据,评价了悬浮性固体(SS)、化学需氧量(COD)、五日生化需氧量(BOD5)、氨氮(NH3-N)和总磷(TP)等水质指标的去除效果。结果表明:该厂实际水量高于设计水量,处于超负荷运行状态,且进水SS浓度较高,BOD5/COD0.4,可生化性一般;主体工艺采用改良A2O工艺,设计停留时间较长,并将二沉池污泥部分回流到初沉池,提高对污染物去除效果,使出水SS、COD、BOD5、NH3-N和TP等指标达到一级A排放标准。进水中偶尔含有冲击性高浓度挥发酚,使污水厂硝化菌功能受抑制,出水NH3-N浓度异常升高,此时该厂通过投加活性污泥进行硝化菌接种,帮助系统尽快恢复正常运行;同时,高盐度工业废水会加速污水厂设备腐蚀。     

膜生物反应器工艺污水处理厂设计进水水质的确定

城市污水处理厂进水水质是工程设计的基本参数,进水水质的测定分析对污水处理厂的设计具有重要意义。对无锡市城北污水处理厂的现状进水水质进行了调查和分析,提出按照水质指标浓度出现的频率确定污水处理厂设计进水水质的方法,并针对采用的膜生物反应器(MBR)工艺的特点,提出:(1)根据实测数据按照一定的保证概率可以用来确定城市污水处理厂设计进水水质;(2)为了使水质的确定更加符合设计工程的实际情况,根据实测数据分析确定设计进水水质指标时,一般还需要进行趋势性调整和季节性调整;(3)确定合理的指标浓度与流量,以此为依据进行反应池的工艺设计,同时要校核夏季温度高、浓度低、流量大和冬季温度低、浓度高、流量小的工况是否满足处理要求,然后取冬、夏季校核值以及未作季节性调整设计值中最不利情况作为设计值,才能充分保证出水达到处理要求。     

昆明市分流制排水区域污水厂进水水质特征的统计学分析

应用多元统计方法系统分析了昆明市某分流制排水区域污水处理厂进水水质特征.结果表明,95％保证率时,该污水处理厂进水BOD5、COD、SS、TN、NH3-N和TP质量负荷分别为11 100、30 000、39 400、2 000、1 600和390 kg/d.进水水质指标中除了SS和NH3-N之间无相关性外,其余各指标间显著相关(α＜0.01).进水SS分别与BOD5、TP、COD有较强的相关性,其Pearson相关系数分别为0.845、0.786和0.915,进水BOD5分别与TP、COD亦有较强的相关性,其Pearson相关系数分别为0.808和0.918.进水BOD5/TN值＞4和BOD5/TP值＞20的累积概率分别为35％和94％,表明该污水处理厂进水有机物浓度不能满足微生物反硝化的需求,但可满足生物除磷对有机物和磷的理论需求量.     

生活污水不同进水C/N比负荷对垂直潜流式人工湿地排放温室气体的影响

人工湿地处理的生活污水含氮量或者有机物含量很高时,可能会造成人工湿地在处理污水的过程中排放大量温室气体。研究了垂直潜流式人工湿地在人工合成的生活污水不同污染物进水C/N负荷条件下污水处理效果和温室气体(CO2和CH4)的排放量,利用现场测量和碳平衡模型估算分析了可以达到最佳污水净化效果和最少温室气体排放量的污染物进水C/N负荷条件。结果显示,在进水C/N负荷为C/N=6∶1~9∶1时可以得到最佳的污染物去除率。温室气体CH4排放量较CO2排放量可以忽略不计,而在进水C/N负荷为C/N=3∶1~6∶1时可以实现最少的温室气体排放。综上所述,最优的进水C/N负荷确定为C/N=6∶1,此时人工湿地可以得到较高的污染物去除率而排放较少的温室气体。     

硫酸庆大霉素废水处理的研究

抗生素工业废水具有成分复杂、污染物浓度高、色度大、生物毒性等特点,比较难于治理。硫酸庆大霉素是常用的抗生素之一,其废水除具备上述特点外,还存在pH值波动范围大、水质、水量不均、SO42-浓度高等问题。本研究采用交换母液絮凝过滤-水解酸化-IC-SBR-MBR工艺处理含有硫酸庆大霉素的废水,在进水COD浓度6 000 mg/L～10 000 mg/L、SS浓度2 000 mg/L～3 000 mg/L的条件下,通过优化交换母液絮凝过滤药剂用量、水解酸化池废水停留时间、IC池的容积负荷、SBR池、MBR的污泥负荷等处理工艺,使出水水质能够达到COD 60 mg/L、BOD5 10 mg/L、NH3-N 10 mg/L。     

连锁控制的A~2/O-MBR工艺处理石化社区生活污水

采用连锁控制的A2/O-MBR工艺处理石化社区低浓度的生活污水并回用,处理规模520 m3/h。工程运行监测结果表明,该工艺对低浓度生活污水处理效果良好,出水水质达到了《城镇污水处理厂污染物排放标准》(GB18918-2002)的一级B标准和《污水再生利用工程设计规范》(GB50335-2002)标准要求。通过连锁控制,系统运行稳定,具有较强的耐冲击负荷能力,实现了污水处理厂正常运行。     

三峡库区城市污水处理厂工艺特征分析

为了分析三峡库区(重庆)城市污水处理厂的工艺特性,对库区现有45座城市污水处理厂进行了调研。发现库区以5万m3/d以下规模的污水处理厂为主,占总数的89%。A/A/O系列工艺、氧化沟系列工艺和SBR及其变型工艺为主流主体工艺,其中占总数64%的污水处理厂选用了氧化沟系列工艺。水质参数的设置与工艺密切相关。污水中无机物含量较高,59%的污水处理厂的MLSS在4~6 g/L之间,71%的污水处理厂的MLVSS/MLSS在0.7以下。三峡库区城市污水处理厂进水水质波动大,碳源较充足,可生化性较好。另外,总结了污水处理厂运行中易出现的问题及建议措施。     

次氯酸钠发生器的研制

介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠     

Estimation of uncertainty of sampling for analysis of pesticide residues

Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.     

An application of the theory of kinematics of mixing to the study of tropospheric dispersion

The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.     

不同泥源对厌氧氨氧化反应器启动的影响

采用2套上流式生物膜反应器,分别接种少量厌氧氨氧化污泥和大量硝化污泥,考察其对厌氧氨氧化反应器启动的影响。污泥接种入反应器后,测得接种厌氧氨氧化污泥的反应器(R1)内MLSS为0.22 g/L,另一个反应器(R2)MLSS为2.7 g/L。与直接接种厌氧氨氧化污泥相比,R1经过72 d的运行才显现出厌氧氨氧化特性。经过114 d的培养,前者氮去除速率由0.23 kg/(m3.d)提升到5.29 kg/(m3.d),总氮去除率大于89%;R2的氮去除速率由0.01 kg/(m3.d)提升到1.1 kg/(m3.d),总氮去除率大于84.6%。说明普通污泥启动需要一个较长的筛选过程,直接接种少量的厌氧氨氧化污泥比接种普通的污泥能够更快启动厌氧氨氧化反应器。     

Evaluation of the presence of drugs of abuse in tap waters

A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L⁻¹, in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L⁻¹. Illicit drugs were sparsely present and usually at ultratrace level (<1 ng L⁻¹). For example, cocaine has mean values of 0.4 (Spain) and 0.3 ng L⁻¹ (worldwide), whereas for benzoylecgonine, these mean values were 0.4 and 1.8 ng L⁻¹, respectively. Higher concentrations of benzoylecgonine were found in Latin American samples (up to 15 ng L⁻¹). No opiates were identified in any sample but the presence of methadone and EDDP was frequently detected. Total mean values for EDDP were 0.4 ng L⁻¹ (Spain) and 0.3 ng L⁻¹ (worldwide). Very few samples tested positive for amphetamines, in line with the reactivity of chlorine with these compounds. No cannabinoids, LSD, ketamine, fentanyl and PCP were detected.     

Mechanisms of biodegradation of dibenzoate plasticizers

Biodegradation mechanisms were elucidated for three dibenzoate plasticizers: diethylene glycol dibenzoate (D(EG)DB), dipropylene glycol dibenzoate (D(PG)DB), both of which are commercially available, and 1,6-hexanediol dibenzoate, a potential green plasticizer. Degradation studies were done using Rhodococcus rhodochrous in the presence of pure alkanes as a co-substrate. As expected, the first degradation step for all of these systems was the hydrolysis of one ester bond with the release of benzoic acid and a monoester. Subsequent biodegradation of the monobenzoates of diethylene glycol (D(EG)MB) and dipropylene glycol (D(PG)MB) was very slow, leading to significant accumulation of these monoesters. In contrast, 1,6-hexanediol monobenzoate was quickly degraded and characterization of the metabolites indicated that the biodegradation proceeded by way of the oxidation of the alcohol group to generate 6-(benzoyloxy) hexanoic acid followed by β-oxidation steps. This pathway was blocked for D(EG)MB and D(PG)MB by the presence of an ether function.The use of a pure hydrocarbon as a co-substrate resulted in the formation of another class of metabolites; namely the esters of the alcohols formed by the oxidation of the alkanes and the benzoic acid released by hydrolysis of the original diesters. These metabolites were biodegraded without the accumulation of any intermediates.     

造纸废水混凝处理中SFT助凝替代性研究

中小造纸厂废水处理常用PAC作混凝剂 ,PAM作助凝剂。由于PAM成本很高 ,影响了处理设备的投运率。用超细滑石粉 (SFT)替代PAM助凝 ,与混凝剂PAC配合 ,其混凝处理效果基本相当 ,但是处理成本降低 0 .10元 /m3 。由于SFT属环境无害材料 ,不会给排泥带来二次污染     

混凝试验搅拌器的研制

影响混凝效果的因素众多,混凝沉淀烧杯试验是进行水的混合、絮凝、沉淀工艺研究、设计和生产指导的最有效方法之一,阐述了智能型混凝试验搅拌器的设计原理和技术性能.     

生物质快速热裂解主要参数对生物油产率的影响

以松木木屑为原料,在自制的小型流化床上,开展了生物质热裂解温度、生物质粒径和进料速率对生物油产率的影响实验研究.结果表明,在热裂解温度分别为450、475、500、525和550℃条件下,当热裂解温度为500℃时,生物油产率最高,平均产率达到53.33%(质量百分比).反应温度越高,炭产量越低,不可冷凝气体产量越高,气体发热值越高;粒径＜1 mm的生物质其粒径对生物油产率影响不大;生物质进料速率增加时,生物油产率增加.本研究为生物能的利用提供了新的途径.     

Visualisation of the complexity of EUSES

The interdependencies of parameters applied in the models of EUSES are visualised in a directed connectivity graph. The parameters (inputs, defaults, state variables, outputs) are represented by boxes (nodes) and their relations by lines (edges). The visualisation, on the one hand, clarifies the complexity of the models in EUSES and, on the other hand, creates an overview and transparency. The parameters’ relations to each other can be recognised faster, and the models can be better understood. The complexity was quantified by the number (variety), kind (substance parameter, physico-chemical parameter, concentration, other parameters), and depth (dimension) of the parameter and the number of relations (connectivity). The variety of EUSES (without the modelsSimple Treat andSimple Box whose interior structure is not documented and without the effect and risk characterisation) amounts to 466, the connectivity to 961, and the maximal dimension is 21.