污水的内含能及污水处理过程的耗能与节能

污水处理是一个高能耗、低能效的复杂过程。改变传统认知,将污染物当作能量物质加以资源化,回用于水处理过程或者产品化,可改变污水处理的能耗。以城市污水与焦化废水为例,分析了水质中污染物具有的内含能形式,并探讨了两种计算方法,指出内含能利用的两类可能途径和最大限度。基于热力学基本定律与污水水质特征,辅以适当的当量假设,分析了污水处理过程中的不同形式能量消耗及其原因,运用能流图表达了两个具体案例的能量转化与分布规律。比较了污水处理两类节能评价方法的优异性,提出了未来水处理可能的节能新途径。在加深污水内含能认识的基础上,结合相关产业与工艺技术,分离回收有价值成分,如营养物(氮、磷)、重金属等,并获得水资源的再利用,以间接补偿处理过程的能耗,从而实现节能目标。     

Removal of trace organic chemicals in onsite wastewater soil treatment units: A laboratory experiment

Onsite wastewater treatment is used by 20% of residences in the United States. The ability of these systems, specifically soil treatment units (STUs), to attenuate trace organic chemicals (TOrCs) is not well understood. TOrCs released by STUs pose a potential risk to downstream groundwater and hydraulically-connected surface water that may be used as a drinking water source. A series of bench-scale experiments were conducted using sand columns to represent STUs and to evaluate the efficacy of TOrC attenuation as a function of hydraulic loading rate (1, 4, 8, 12, and 30 cm/day). Each hydraulic loading rate was examined using triplicate experimental columns. Columns were initially seeded with raw wastewater to establish a microbial community, after which they were fed with synthetic wastewater and spiked with 17 TOrCs, in four equal doses per day, to provide a consistent influent water quality. After an initial start-up phase, effluent from all columns consistently demonstrated >90% reductions in dissolved organic carbon and nearly complete (>85%) oxidation of ammonia to nitrate, comparable to the performance of field STUs. The results of this study suggest STUs are capable of attenuating many TOrCs present in domestic wastewater, but attenuation is compound-specific. A subset of TOrCs exhibited an inverse relationship with hydraulic loading rate and attenuation efficiency. Atenolol, cimetidine, and TCPP were more effectively attenuated over time in each experiment, suggesting that the microbial community evolved to a stage where these TOrCs were more effectively biotransformed. Aerobic conditions as compared to anaerobic conditions resulted in more efficient attenuation of acetaminophen and cimetidine.     

Modelling the urban water chain: Incentives and cost recovery in wastewater treatment in developing countries

To improve surface water quality in developing countries new approaches to design wastewater treatment schemes have been developed. We identify a compliance problem in these schemes which threatens their success. To analyze this problem, we integrate a compliance game into a model of the urban water chain. We illustrate the model with a numerical example on small scale leather processing. We find that the compliance problem indeed threatens the overall success of the treatment scheme and show under which conditions this is so. With an empirical calibration our model is a ready to use tool to provide quantitative results that can inform planners of urban wastewater treatment schemes.     

Diurnal variations in the occurrence and the fate of hormones and antibiotics in activated sludge wastewater treatment in Oslo, Norway

We present an assessment of the dynamics in the influent concentration of hormones (estrone, estriol) and antibiotics (trimethoprim, sulfamethoxazole, tetracycline, ciprofloxacin) in the liquid phase including the efficiency of biological municipal wastewater treatment. The concentration of estradiol, 17-α−ethinylestradiol, doxycycline, oxytetracycline, demeclocycline, chlortetracycline, cefuroxime, cyclophosphamide, and ifosfamide were below the limit of detection in all of the sewage samples collected within this study. Two different types of diurnal variation pattern were identified in the influent mass loads of selected antibiotics and hormones that effectively correlate with daily drug administration patterns and with the expected maximum human hormone release, respectively. The occurrence of natural hormones and antimicrobials, administered every 12 hours, shows a daily trend of decreasing contaminant mass load, having the maximum values in the morning hours. The occurrence of antibiotics, typically administered every 8 hours, indicates a daily peak value in samples collected under the highest hydraulic loading. The efficiency of biological removal of both hormones and antibiotics is shown to be limited. Compared to the values obtained in the influent samples, increased concentrations are observed in the biologically treated effluent for trimethoprim, sulfamethoxazole and ciprofloxacin, mainly as a result of deconjugation processes. Ciprofloxacin is shown as the predominant antimicrobial compound in the effluent, and it is present at quantities approximately 10 fold greater than the total mass of the other of the compounds due to poor removal efficiency and alternating solid-liquid partitioning behaviour. Our results suggest that, to increase the micro-pollutant removal and the chemical dosing efficiency in enhanced tertiary treatment, significant benefits can be derived from the optimisation of reactor design and the development of control schemes that accounts for diurnal secondary effluent micro-pollutant and hydraulic loading patterns.     

电热水器运行方式与能耗的理论分析

运用总传热系数法,建立电热水器的物理模型及相应耗热量的数学模型。通过对电热水器不同运行方式能耗的理论计算,指出电热水器连续运行更加节能,为电热水器的节能提供了新的方向。     

Energy consumption in an urban wastewater treatment plant: the case of Murcia Region (Spain)

Of all the costs associated with the operation and maintenance of wastewater treatment plants (WWTPs), those associated with energy use tend to be the most significant. From this point of view, it is hence logical that energy efficiency and saving strategies should be one of the current focuses of debate amongst those involved with the management of WWTPs. The present study's objective is to determine the correlation between size and energy consumption for a WWTP. To this end, 90 WWTPs currently in service were analysed and their energetic impact quantified in terms of kWh/m³ of water treated. The results obtained demonstrate that energy consumption ratio increases as the size of WWTPs decreases, either in terms of treatment volume or population equivalent served.     

The impact of horizontal water velocity on the energy consumption of a full‐scale wastewater treatment plant

This study quantifies the impact of the oxidation ditch horizontal water velocity on the energy consumption of a full‐scale wastewater treatment plant (WWTP). A WWTP was modelled by means of the ASM2d platform, showing very good correlation with reference operational data. As to reduce the energy requirements of the plant while guarantying the same nutrient removal performance, two approaches were used. A classical aeration control optimization, yielding a 4% energy reduction, was compared with an increase of the oxidation ditch propelling power. The horizontal water velocity in the oxidation ditches was estimated at only 0.15 m/s. By increasing the horizontal water velocity to 0.3 m/s, an 8% energy reduction could be achieved. Moreover, a synergistic effect for classic control optimization and oxidation ditch water velocity optimization resulted in a 14% energy reduction. Energy spent in propelling power counteracts the aeration energy gain derived by an increase in the oxidation ditch horizontal velocity. An optimum in the water velocity was quantified at 0.3 m/s, comparably with its design value.     

Infrastructure epistemologies: water,wastewater and displaced persons in Germany

Recent years have seen historically unprecedented global disaster migration; in 2016 Germany received 1.3 million displaced individuals. Regardless of past resources and future potential, disaster migrants are a new, vulnerable population. This new population increases demand for water and wastewater infrastructure services, despite being temporarily unable to pay for services. As such, this kind of sudden population increase is a resiliency challenge for the receiving infrastructure systems. Qualitative analysis of 1,884 open-ended survey responses was blended with a statistical analysis to discover how and why the German public perceives water and sanitation services have been provided to the disaster migrants. Unprompted, 36% (112/314) of respondents referenced at least one of three infrastructure epistemologies, including water and wastewater as a service, as a basic need, and as a human right. These epistemologies share statistically significant relationships with how long respondents feel water and wastewater should be provided to displaced persons. A temporally limited, normative perception of water and sanitation as a humanitarian good functions to enable water and wastewater infrastructure to deliver a high level of service despite the significant disruption of the large and vulnerable population influx, and has practical implications for the structure of cost recovery.     

膨润土的改性研究及在污水治理中的应用

介绍了蒙脱石的结构和基本性质 ,对近年来我国膨润土的活化、改性技术如焙烧活化、酸活化、无机改性、有机改性、交联膨润土的合成和改性机理及改性效果进行了归纳总结。活化改性改善了蒙脱石的微观结构 ,提高了膨润土的吸附能力和离子交换能力 ;对改性膨润土在污水治理中的应用进行了综述。改性膨润土可去除水体中的重金属离子、芳香族化合物、有毒难生物降解有机物 ,还具有脱色、脱磷、除臭等作用。给出了改性膨润土去除水中重金属离子、有机污染物的机理。指出了膨润土在污水处理中存在的问题 ,并展望其应用前景 ,认为膨润土是一种很有前途的污水处理材料。     

微生物絮凝剂用于废水处理的研究及其应用

论述了微生物絮凝剂的种类、絮凝机理、影响因素及其在废水处理中的具体应用,讨论了微生物絮凝荆在目前应用中存在的问题,并对其应用前景做了展望。     

Cost-effectiveness analysis of sewer mining versus centralized wastewater treatment: Case study of the Arga river basin,Spain

In the context of the EU Water Framework Directive, a cost-effectiveness analysis (CEA) was performed to compare centralized and decentralized wastewater treatment strategies aimed to improve the ecological status of a Spanish river. The implementation of several hybrid membrane bioreactors within the urban framework for sewer mining (SM) was compared with the more common wastewater treatment plant enlargement option. The assessment ranked six alternatives based on 12 potential scenarios, aimed at narrowing the uncertainty of the CEA. The cost analysis illustrated that SM is the most expensive option in regard to both investment and operation and maintenance costs. However, the effectiveness of the alternatives evaluated depends significantly on the scenarios considered, with SM the most effective in most cases. Finally, the cost-effectiveness ratio showed SM as the best cost-effective alternative. CEA provides an ecological-economic indicator useful to prioritize wastewater treatment alternatives to achieve a given objective.     

蒸气压缩式冷水机组生产能耗和资源消耗分析

采用厂家调研、产品样本数据和相关资料分析相结合的方法,对一些不同品牌、不同类型的蒸气压缩式空调冷水机组的材料资源消耗和生产能耗进行定量分析,得到了常用冷水机组的材料组成、耗材系数和生产能耗数据,这些研究结果为建筑空调寿命周期能耗及环境影响评价、设计方案优选和节材工作提供了重要的基础数据.     

Comparison of UV-Cl and UV-H2O2 advanced oxidation processes in the degradation of contaminants from water and wastewater: A review

Applications of advanced oxidation processes (AOPs) in water and wastewater treatment have been the subject of growing interest throughout the last decade. Although UV/hydrogen peroxide (UV-H₂O₂) is the most established technology among the UV-AOPs, UV-chlorine (UV-Cl) is emerging as a reliable and potentially more cost-effective alternative. Recent studies have indicated that UV-Cl processes may be more efficient and economically favourable for the degradation of some chemicals of emerging concern from contaminated water. Moreover, in terms of the formation of disinfection by-products (DBPs), UV-H₂O₂ seems to have no superiority over UV-Cl. This said, more investigation in the assessment of genotoxicity and cytotoxicity of DBPs is required. Additionally, more pilot-scale and full-scale studies are required to establish UV-Cl as a reliable alternative to UV- H₂O₂. This paper compares UV-Cl and UV-H₂O₂ AOPs for the degradation of intractable chemicals from water and wastewater based on the practical considerations of efficiency, cost, DBP formation, kinetics and sensitivity to water matrix variability. Finally, various modelling approaches to UV-Cl have been reviewed. This review showed that UV-Cl is superior to UV-H₂O₂ in terms of degradation efficiency and cost effectiveness and can be a robust alternative in many UV-AOPs applications.     

变频调速水泵在住宅小区中的能耗分析

针对小区建筑的各种给水方式,运用实例数据进行了能耗比较。通过比较分析得出了最适合小区住宅的给水方式,并针对小区住宅的给水方式选择提出了建议,可供小区住宅供水设计参考。     

Performance management of small water treatment plant operations: a decision support system

A decision support system (DSS) is developed to optimise the performance of different operations of small water treatment systems to improve day‐to‐day decisions. The support system includes a data management system, knowledge‐based system, performance assessment of different unit processes, fault tree analyses, preventive and corrective actions and event tree analysis (ETA). Performance assessment identifies the critical events (failures) and fault tree analysis identifies the interrelationships between the critical events and the root causes. Fault trees are developed based on the information obtained from events of waterborne outbreaks, responses to questionnaires by the participating smaller utilities, state‐of‐the‐art literature review and personal communication with the operators. ETA is used to identify the potential health outcomes which are further integrated with the quantitative microbial risk assessment. The developed DSS is advanced to an automated user friendly program that can be used by treatment plant operators to assess system performance.     

谈大中城市小型污水厂的建设

以济南市小型污水处理厂的建设规划为背景,介绍了近期拟建污水处理厂的情况,分析了目前污水处理存在的问题,提出了应将污水处理和节水相结合的思路,从而提高城市污水处理率和中水回用率,节约水资源。     

Bioassays as a tool for evaluating advanced oxidation processes in water and wastewater treatment

Advanced oxidation processes (AOPs) have been widely used in water and wastewater treatment for the removal of organic and inorganic contaminants as well as to improve biodegradability of industrial wastewater. Unfortunately, the partial oxidation of organic contaminants may result in the formation of intermediates more toxic than parent compounds. In order to avoid this drawback, AOPs are expected to be carefully operated and monitored, and toxicity tests have been used to evaluate whether effluent detoxification takes place. In the present work, the effect of AOPs on the toxicity of aqueous solutions of different classes of contaminants as well as actual aqueous matrices are critically reviewed. The dualism toxicity-biodegradability when AOPs are used as pre-treatment step to improve industrial wastewater biodegradability is also discussed. The main conclusions/remarks include the followings: (i) bioassays are a really useful tool to evaluate the dangerousness of AOPs as well as to set up the proper operative conditions, (ii) target organisms for bioassays should be chosen according to the final use of the treated water matrix, (iii) acute toxicity tests may be not suitable to evaluate toxicity in the presence of low/realistic concentrations of target contaminants, so studies on chronic effects should be further developed, (iv) some toxicity tests may be not useful to evaluate biodegradability potential, in this case more suitable tests should be applied (e.g., activated sludge bioassays, respirometry).     

深圳市大型公共建筑能耗监测系统运行维护及检测数据案例分析

介绍了深圳市大型公共建筑能耗监测系统的运行维护情况,对监测数据进行了分析.一方面,总结了监测系统运行维护工作量大的原因,提出了相应的解决措施;另一方面,通过分析典型办公建筑能耗监测数据,提出了建筑在设备选型、用能管理、用户行为等方面的改进意见.为大型公共建筑能耗监测系统的运行维护和数据分析提供借鉴.     

纺织污水处理厂厌氧水解及接触氧化工艺调试

介绍了空港经济区纺织污水处理厂＂厌氧水解＋接触氧化＋化学混凝法＋沉淀分离＂组合工艺的运行调试过程,针对纺织废水水质间歇性超标、水质波动大以及纺织废水与市政污水的比例波动等问题,通过合理调整气水比、溶解氧、生物膜厚度、加药量等工艺参数,使系统的出水水质达到了设计要求,可为同行业污水处理厂的试运行调试提供参考。     

隧道工程水害防治研究

分析了地下水对隧道工程的危害性,为了避免和消除地下水对隧道的危害,采用截、堵、排综合使用的原则,并提出了防治水害的措施,以期从根本上解决隧道工程水害治理难的问题,并保证隧道的正常施工和使用。