Stable Isotopic Signatures of NO3 in Waste Water Effluent and Los Angeles River

A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health.

Current Seasonal Variations in Physicochemical and Heavy Metals Parameters of Sewage Treatment Plant Effluent and Suitability for Irrigation

The study aims to investigate the current extent of physicochemical parameters and heavy metal contamination in the effluent of the Jaganpur sewage treatment plant (STP), Dayalbagh, Agra India. Majority of the nearby farmers have access to use of STP effluent in irrigation purposes for growing major edible crops. The problems of using STP effluent for irrigation purpose, continuous water quality analysis required. To check the quality of irrigation water, substantial physicochemical parameters accordance to Indian Standards (IS-Reaffirmed 2002/2003) analysed to calculate Sodium absorption ratio (SAR) and Residual sodium carbonate (RSC). To estimate the heavy metal pollution index (HPI) and metal quality index (MQI), toxic Heavy metals such as As, Cr, Mn, Fe, Ni, Cu, Zn, Pd, Cd, Co, and B also determined in the STP effluent with an AAS and results verified with ICP-OES against certified standards. The high value of SAR (range 13 to 20) and RSC (range -10 to 11) in STP effluent exceeded the permissible limit for irrigation purpose. On the other hand, HPI and MQI values (1692.4 and 58.1, respectively) show that high metal contamination mainly due to industrial and domestic wastewater does not treat appropriately in the sewage treatment plant. Thus it is suggested that further studies are carried out on the STP effluents to improve the water quality through proper treatment. Treated wastewater used for irrigation purposes needs to analyse the contamination like heavy metals and pinpoint the pollution sources.

Water Analyses, Eco-Balance and Socio-Demographic Analyses as Prerequisites for Solutions of the Sewage Treatment Problems in Rural Areas

The implementation of the EU-water framework directive (EU-WFD) demands a financeable and adaptable sewage treatment, creating a need for action especially in rural areas, where the “good ecological status” is often not reached even though the sewage works fulfill the legal minimum requirements. Therefore the construction of new, more efficient wastewater treatment plants is advisable. Due to the precarious financial situation in most rural areas, many municipalities can however not master the necessary funds for an improved waste water infrastructure. A large part of the costs would have to be shouldered by the local population in the form of additional sewage levies, leading to massive socio-economic strain. Hence, different solutions, which are tailored to the socio-economic, demographic and environmental characteristics of rural areas and fulfill the legal requirements, need to be developed. One possible approach is presented in the form of the Dirlammen case study (municipality Lautertal, Hesse, Germany). It consists of 1) biological and physicochemical analyses of the waste waters, 2) a modified eco-balance for the construction of a new sewage works and 3) socio-economic and demographic analyses of the population. It serves as a tool for the assessment of the influencing ecological, socio-economic and demographic factors on the sewage problems in rural areas. These findings can easily be transferred to other rural areas with a similar configuration and thus deliver the basis for a generally applicable approach to these problems. The results of the comprehensive analysis have shown for the municipality Dirlammen/Lautertal that the continued operation of the existing pond sewage plant is, with regards to the ecological, socio-economic and demographic points of view, preferable to the construction of a new waste water treatment plant. With regard to the sustainability principles of the sewage treatment and the objectives of the EU-WFD, existing sewage works should be operated for as long as the sewage treatment is feasible within technical and legal boundaries. With the construction of new facilities on the other hand, the expected improvement of the water quality has to be weighed against the ecological impairments caused by the construction itself. Rural waste water plans have to be developed for the long-term, taking not only the ecology into account but also the demographic change. Possible approaches in this regard could be a shift towards a decentralized waste water treatment concept and–even more important–improvements of the river morphology. But also the reduction of the diffuse pollution from agricultural sources should be considered for the development of strategies for the improvement of the ecological state. Short-term optimization measures in the existing sewage works might also improve the water quality until the long-term development plans can be implemented. In particular the challenges of the demographic change and linked with that the changing requirements for the rural waste water treatment must be addressed by any future plans. Only with the help of such a comprehensive approach the dangers of bad planning and unacceptable socio-economic burdens can be minimized.

Behavior of Antibiotic-Resistant Fecal Coliforms in the Stream of a Sewage Treatment Plant in Tokyo

We are confronting a new threat in the prevalence of antibiotic-resistant bacteria followed by epidemic spread in aquatic environments in metropolitan areas because damage from river floods is increasing remarkably in Japan due to global extreme weather. The sewer penetration rate is about 100% in Tokyo and reclaimed water from sewage treatment plants accounts for over 50% of all water in both the down- and mid-stream areas of local rivers. The water quality of these rivers, which contain microflora, seems to be seriously affected by reclaimed water. In this study, we collected water samples on July 17, 2018 and examined the behavior of antibiotic-resistant fecal coliforms in the stream of a sewage treatment plant in Tokyo. Extended-spectrum β-lactamase (ESBL)-producing fecal coliforms with encoding genes were found;the CTX-M-1, CTX-M-9, TEM, and SHV groups were found to have survived in the final effluent to the river after sterilization with sodium hypochlorite.

Experimental Study on Anaerobic Digestion of Remaining Sludge in Municipal Wastewater Treatment Plant

Along with the development and progress of environmental protection management,it is necessary to pay full attention to the disposal of excess sludge in the process of urban sewage treatment plant management.It is necessary to ensure effective integration of management mechanisms and management paths.To a certain extent,it can improve the actual efficiency of digestion and treatment work and lay a foundation for the optimal operation of environmental protection management.In this paper,the treatment of excess sludge in a sewage treatment plant is studied.The method and results of anaerobic digestion test of excess sludge in a sewage treatment plant are discussed for reference only.

城市污水处理厂进水水质分析及MBR膜生物处理工艺研究

为提高城市污水的处理效率,在分析了某城市污水处理厂进水水质指标的基础之上,对目标城市污水开展了MBR膜生物处理工艺技术研究,并对其处理效果进行了分析。结果表明,目标城市污水处理厂进水水样中污染物的浓度较高,其中COD、NH_(3)-N、TN、TP、SS的平均浓度分别为202.8mg·L^(-1)、38.3mg·L^(-1)、50.8mg·L^(-1)、6.1mg·L^(-1)、261.6mg·L^(-1)。采用MBR膜生物处理工艺对目标城市污水进行处理后,12个月的出水水质中污染物的含量均大幅降低,其中COD、NH3-N、TN、TP、SS的浓度平均值分别为9.82mg·L^(-1)、0.94mg·L^(-1)、8.41mg·L^(-1)、0.35mg·L^(-1)、1.93mg·L^(-1),各项指标均能达到国家标准GB 18918-2002中的一级A标准要求。研究结果认为,MBR膜生物处理工艺对目标城市污水具有较好的处理效果,可为同类城市污水的高效处理提供一定的借鉴。

Characterization, treatment and releases of PBDEs and PAHs in a typical municipal sewage treatment plant situated beside an urban river, East China

Characterization, treatment and releases of eight polybrominated diphenyl ethers （PBDEs） congeners and sixteen polycyclic aromatic hydrocarbons （PAHs） in wastewater were evaluated along the treatment processes of a typical secondary treatment municipal sewage treatment plant （STP） （in Hefei City） situated the beside Nanfei River, East China. The findings showed that the average concentrations of the total PBDEs in raw wastewater and treated effluent were 188.578 and 36.884 ng/L respectively. Brominated diphenyl ether （BDE） 209 congener, the predominant PBDE in the STP and Nanfei River, could be related to the discharge of car-industry-derived wastes. For PAHs, the average concentrations in raw wastewater and treated effluent were 5758.8 and 2240.4 ng/L respectively, with naphthalene, benzo[a]pyrene and indeno[1,2,3-c,d]pyrene being detected at the highest concentrations. PAHs mainly originate from the combustion of biomass/coal and petroleum. The STP reduced about 80% of the PBDEs and 61% of the PAHs, which were eliminated mainly by sedimentation processes. The removal rates of PBDEs/PAHs increased with the increase of their solid-water partitioning coefficients. Accordingly, the STP＇s effluent, containing some PBDE congeners （e.g., BDE 47, 99 and 209, etc.） and low-molecular-weight PAHs, could be an important contributor of these contaminants＇ input to Nanfei River. It resulted in a significant increase of PBDE/PAH concentrations and PAH toxicological risk in the river water downstream. About 4.040 kg/yr of PBDEs and 245.324 kg/yr of PAHs could be released into the Nanfei River. The current conventional wastewater treatment processes should be improved to remove the relatively low-molecular-weight PBDEs/PAHs more effectively.

基于减污降碳和水质目标约束下的黄河干流兰州段城区污水处理厂出水排放限值研究

为科学合理地提出黄河干流兰州段城区污水处理厂出水排放限值,实施精准科学治污,持续改善黄河干流兰州段水环境质量,本文以兰州市城区四座有代表性的污水处理厂(西固、七里河安宁、盐场和雁儿湾污水处理厂)为研究对象,统计四座污水处理厂主要污染物排放浓度、中水回用率、主要污染物去除率及减排效果,分析四座污水处理厂入河排污对黄河干流兰州段水质的影响,梳理污水处理厂运行阶段的碳排放情况.结果表明:(1)兰州市城区四座污水处理厂中水回用率低,介于0.86%~4.66%之间.(2)四座污水处理厂主要污染物的去除率高于国内污水处理厂主要污染物去除率的平均水平,COD、NH_(3)-N年均减排量分别为114584.1、8234.6 t,减排效果明显.(3)在黄河枯水期上游来水水量小、水质接近或超出GB 3838-2002《地表水环境质量标准》Ⅱ类水质目标限值的条件下,叠加区间其他入河排污口的影响,兰州市城区四座污水处理厂均按照设计规模及设计出水水质排污会对下游河段水质造成影响.因此,不能一味地追求出水水质,盲目提标改造,要综合考虑污水处理厂运行过程中的碳排放,在满足受纳水体水质目标前提下,统筹考虑减污降碳.

长江大保护试点城市某污水处理厂尾水湿地净化效果研究

为探寻污水处理厂配套尾水湿地净化效果,以长江大保护试点城市某污水处理厂尾水湿地为例,通过现场调查与采样,分析湿地出水水质特征,探讨影响湿地污染物去除效率因素。结果表明:尾水湿地出水COD、NH_(3)-N及TP浓度满足设计目标,潜流湿地对COD去除率较高,表流湿地对氨氮及磷的去除率较高,优于涵养塘;湿地实际运行水力负荷、水力停留时间和污染物负荷与设计值不符,影响污染物去除效果;据此提出湿地运行优化建议,促进湿地深度脱氮除磷,提升尾水湿地效能;运行优化可提高潜流湿地污染物去除率,同时污水处理厂减少碳排放94.74 gCO_(2)m^(3)。研究结果可为该尾水湿地运行管理及长江大保护试点城市系列污水处理厂配套尾水湿地设计与运维提供参考。

佛山市某污水厂技改工程实例

介绍了佛山某污水处理厂技改工程的工艺流程和设计参数。在用地紧张的条件下,改造原有构筑物,新建“深度处理+超滤反渗透+浓水处理”为主体工艺的中水回用系统。实际运行结果表明,技改后满足扩容减排的政策要求,出水水质稳定达标排放,为类似污水处理厂的技改提供了相关设计经验。

东北地区某城镇污水处理厂碳源投加策略分析

低C/N进水条件造成的生物处理系统反硝化脱氮能力不足已成为我国污水处理厂运行面临的主要挑战。文章应用文献计量学对目前碳源投加策略进行了总结,并以东北地区某城镇污水处理厂为考察对象,结合各碳源的实际应用情况介绍了目前常用的几种主流外加碳源的优缺点,分析了甲醇、乙酸钠、葡萄糖和麦可碳4种碳源投加公式计算理论值与实际碳源投加量之间存在差异的原因,旨在为城镇污水处理厂实现经济、高效、低碳运行碳源投加策略提供技术指导。

滨海河网地区城镇污水处理厂污泥产率影响因素研究

本文以广州市滨海河网地区4座典型城镇污水处理厂为研究范围,分析了进水COD、BOD、SS浓度以及气温等对污泥产率的影响。研究结果表明:(1)滨海河网地区城镇污水处理厂的污泥产率相对较低,不同污水处理工艺的污泥产率季节变化规律不同,CASS工艺夏季污泥产率较高,AAO工艺秋季污泥产率较高;(2)污泥产率与进水水质密切相关,对于进水浓度较低的污水厂,污泥产率与COD、BOD、SS浓度呈现弱的负相关关系,反之,呈现正相关关系,且浓度越高,相关性越强;(3)滨海河网地区四季温差不大,气温对污水厂的污泥产率影响较小。(4)通过控制进水水量水质,优化运行参数优化等措施尽可能保障活性污泥处理系统安全稳定高效运行,实现污泥减量化。

污水处理厂智慧管控平台的设计要点概述

通过研究分析污水处理厂的运行情况,为污水处理厂提供一个可行的智慧水务管理技术方案,全方位提高水厂的管理水平。帮助污水处理厂实现了电子化的生产运行数据记录、信息化的数据查询共享方式、规范化的生产运行管理体系、智能化的数据汇总和统计、高度灵活的报表配置和导出、图形化的数据统计分析结果展现,从而提高生产运行数据的准确性,减少管理人员数据统计分析的工作量,提高生产运行管理效率。并对污水处理系统进行全面检视、改进、优化,提高污水厂运行的自动化、信息化、智能化水平,减少污水厂的能耗、药耗,降低运维人工成本,提升污水厂的经济、环境、社会效益。

典型人工甜味剂在城市污水厂不同工艺段的分布和去除特征

研究调查了6种人工甜味剂(ASs)安赛蜜(ACE)、甜蜜素(CYC)、糖精(SAC)、阿斯巴甜(ASP)、三氯蔗糖(SUC)和纽甜(NEO)在城市污水厂不同工艺段的分布、进出水负荷和去除效果。研究表明,进水CYC和SAC含量最多,占ASs总浓度大于67%,而ASP未被检出。ASs进水负荷为0.0037(NEO)~1.32(CYC)g/d·1000p^(-1),出水负荷为0.0015(NEO)~0.43(SUC)g/d·1000p^(-1)。ACE、CYC和SAC去除效率>88%,主要发生在二级处理段,而NEO与SUC去除效率分别<62%和<10%,主要发生在一级和深度处理段。

进一步改善城市网-厂-水体污水系统升级改造和运行效率的四点看法

2022年,《深入打好城市黑臭水体治理攻坚战实施方案》发布,要求努力解决河流雨后黑臭和雨季河流断面水质下降问题,力争到2025年,进水BOD浓度高于100毫克/升的城市生活污水处理厂规模占比达90%以上,城市生活污水集中收集率达到70%以上。水行业正面临着防止雨后河流返黑和改善雨季河流水质等新任务。因此,结合近年来成绩、实践和欧美的经验教训,提出和讨论了与进一步改善网-厂-水体城市污水系统升级改造及运行效率相关的四个问题:分流制管网有没有外(雨)水入侵和溢流、污水处理厂的进水浓度应多高、为什么部分污水处理厂需局部扩容、为什么污水管道中流速低于自净流速,并在此基础上,对相关工作提出了建议。

A^(2)O-SBR工艺在城镇污水处理厂中的应用

A^(2)O-SBR工艺为A2O工艺与SBR工艺串联组合,为了探究A^(2)O-SBR工艺在城镇污水处理厂的应用效果,分析广西壮族自治区东兴市城东污水处理厂2021年运行情况,结果表明:厂区出水稳定达标排放,A^(2)O-SBR工艺脱氮除磷效果好;COD、NH_(4)^(+)-N、TP平均去除率为87.05%、97.23%、80.86%,最高去除率为97.55%、98.36%、91.21%;出水浓度相对稳定,A^(2)O-SBR工艺对上述三种污染物的去除率也相对稳定,对NH_(4)^(+)-N效果最好,全年去除率稳定达到95%以上;该污水处理厂平均处理成本0.53元/m^(3)。

近自然氧化塘人工湿地对城镇污水厂尾水复合污染物净化效果研究

由于城镇污水厂尾水污染物种类繁多、浓度和流量波动大,因此净化工艺较为复杂,净化效果较差。研究泗洪县地形等概况与近自然氧化塘人工湿地净化机理,预估污水处理量,规定净化前后水质标准。考虑地形地势和水流设计湿地结构,采用化学需氧量测试仪检测、稀释接种法等方法检测COD、BOD_(5)、NH_(3)-N、TN、TP等污染物的含量。结果表明,利用该方法净化城镇污水厂尾水复合污染物后,COD、BOD_(5)、NH_(3)-N、TN、TP的污染物浓度分别为8.0 mg/L、3.9 mg/L、5.0 mg/L、3.1 mg/L、4.4 mg/L,污染物去除率均超过50%。由此证明,该方法能够净化尾水中污染物,净化后的尾水质量较高。

机器学习用于城镇污水处理厂进水预测的实践研究

通过分析比较不同的污水处理厂进水预测方法,并对影响进水情况的有关因素进行相关性分析,采用基于机器学习的BP神经网络模型来预测污水处理厂的日进水量及化学需氧量。利用位于国内南方和北方的两个典型污水处理厂的实际运行数据进行试验,结果显示该模型预测精度良好,与实际数据偏差保持在5%以内。

东南沿海某污水处理厂尾水深海排放设计研究

为进一步提高海底输水管线设计质量,文中以实际工程为研究对象,深入分析污水处理厂尾水深海排放建设项目设计要点,详细介绍了该工程的陆域管线设计思路以及海底管线设计技术要点,重点研究了海底管线工程管道计算、参数设计以及海底管线稳定性分析等的思路。结果表明,本工程设计的海底管线方案满足不同工况需求,研究内容能指导后续工程建设,为海底输水管线设计工作的开展提供参考。

旅客吞吐量对某机场污水处理厂的影响

为研究旅客吞吐量对某机场污水处理厂运行效果的影响,选取该污水处理厂2021—2023年的各项监测指标,包括水量、水质、活性污泥和现场调控工艺等开展研究。结果表明,该污水处理厂各类指标均受到不同程度的影响。其中,处理水量、水质指标总磷和总氮、微生物种类受旅客吞吐量的影响较大。经过工艺的调整,使得2021—2023年的各项出水指标良好,整体运行稳定。