Establishing an Assessment Index System for Sewage Treatment Works in China

1.Introduction The urban sewage treatment system,including sewage pipe networks and sewage treatment plants,is an important infrastructure to ensure urban social and economic operation.In the past few decades,due to the unremitting efforts of the Chinese government,the construction of China’s urban sewage treatment infrastructure has developed rapidly[1].

Application of Anti-clogging Ecological Soil Sewage Treatment Process in Rural Domestic Sewage Treatment and Prospects

[Objectives] By reasonable water distribution and air supply to soil, soil water permeability is maintained, and the nutrient conditions of degrading bacteria in soil are improved to effectively prevent soil clogging. [Methods] Through the innovation and improvement of traditional soil sewage treatment technology, the physical, chemical and biological characteristics of soil for sewage purification are utilized to enhance the pollutant decomposition ability of soil microorganisms and maintain soil water permeability.[Results] It has no secondary pollution, and can effectively remove pollutants such as COD_(Cr), TN, TP, NH_3-N, etc. in sewage. [Conclusions] The operation and maintenance cost is low, and the land can be reused, while water and nutrients can be restored to the land.

Research Progress Related to Rural Domestic Sewage Treatment

Rural domestic sewage treatment is an important part of the rural revitalization strategy and a key action to build a livable, livable and beautiful countryside. This paper composes and summarizes the relevant studies on rural domestic sewage treatment from the governance techniques and modes of governance subjects and research perspectives, in order to provide reference for the implementation of rural revitalization strategy and rural domestic sewage treatment research and action implementation.

First low-carbon association standard for sewage treatment comes into effect

Waterisa precious and indispensable resource that humans rely on every day.To avoid environmental pollution and make full use of water resources,sewage treatment plants are built to recyclewateranddealwith harmful materials.According to the China Association of Environmental Protection Industry,the sewage treatment industry accounts for about 1 percent of the total carbon emissions in China,which is generated by high energy consumption devices and heavy use of drugs.In the context of realizing thecarbon peak emissions and neutrality goals,it is significant to promote scientific and high-efficient technologiestoreduce carbon emissions and promote the green,low-carbon development of ecofriendly industry.

Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method

The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis （DGGE） of nested polymerase chain reaction （nested PCR） amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria.

Levels and distributions of polychlorinated biphenyls in sewage sludge of urban wastewater treatment plants

Concentrations of polychlorinated biphenyls （PCBs） have been measured in sewage sludge samples from 8 urban wastewater treatment plants in Beijing, China. The PCB congeners were analyzed by isotope dilution high resolution gas chromatography/high resolution mass spectrometry method. The concentration of PCBs ranged from 65.6 to 157 ng/g dry weight （dw）, with a mean value of 101 ng/g dw. The dioxin-like PCB WHO-TEQs （World Health Organization-Toxic Equivalents） of the sludge were lower than 1 pg /g dw. Consequently, all the concentrations of PCBs in sludge samples were below the upper limit for land application according to the Chinese legislation law for agriculture use. The PCB homologue profiles in sludge samples were dominated by tri-CBs and tetra- CBs. Similar distributions have been found in one of the Chinese PCB commercial products. The patterns of dioxin-like and indicator congeners observed in this study were quite similar in all samples. The predominant congener for dioxin-like and indicator PCBs were PCB-118 and PCB-28, respectively, while PCB-126 had the highest TEQ value.

Biotransformation of nonylphenol ethoxylates during sewage treatment under anaerobic and aerobic conditions

Biotransformation of nonylphenol ethoxylates （NPEOs） during continuous anaerobic sewage treatment was compared with the aerobic treatment of sewage spiked with 23 μmol/L technical NPEOs over a period of 90 d. Immediate degradation of NPEOs was observed under both anaerobic and aerobic conditions, indicating that the enzymes and bacteria required for NPEO degradation existed abundantly in both aerobic and anaerobic sludge. Both treatments achieved high removal （〉 92%） of the spiked NPEO9 mixture. Liquid chromatography-mass spectrometry （LC-MS） analysis showed that short-chain NPEOs （NPEO1-NPEO3） accumulated in anaerobic （2.01-2.56 μmol/L） and aerobic （1.62-2.03 μmol/L） effluents, with nonylphenol （NP） （0.24-0.31 μmol/L） as another group of metabolites in the anaerobic effluent, and nonylphenoxy carboxylates （NPECs） （2.79-3.30 μmol/L） in the aerobic effluent. Significant accumulation of NP in the anaerobic sludge and NPEO1-3 in the sludge of two reactors was observed. These results indicated that it was difficult to control these harmful metabolites in the conventional treatment processes. Denaturing gradient gel electrophoresis profiles of sludge samples support the speculation that the NPEO degradation bacteria might be the dominant indigenous species.

The Application of PLC in Sewage Treatment

The environmental protection has become one of the factors that affect and restrict the development of human society. With the continuous development of industry and the rapid increase of urban population, a large number of industrial and domestic sewage discharges into rivers and lakes without treatment, so that the environment and the application of water are seriously polluted. In this paper, the principle and characteristics of PLC(PLC is the abbreviation of Programmable Logic Controller)are introduced;the process of PLC sewage treatment is expounded, and the application of PLC in sewage treatment is described.

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.

Study on Ecological Landscape Design in Rural Sewage Treatment-Taking Sanmenxia Lushi Sewage Treatment Station as an Example

The problem of water pollution is one of the long-term difficulties in the process of rural environmental construction and economic development in China.In order to meet the requirements of the country’s green and sustainable development,many regions actively promote the construction of rural sewage treatment and fill in the shortcomings of the rural habitat environment to accelerate the construction of beautiful and livable villages.Through a lot of literature and case studies,this paper explores the environmental problems that are common in rural sewage treatment in the northern region of China,explores advanced domestic and foreign cases and technologies on this topic,and summarizes the landscape design strategies on this issue.From the perspective of ecological landscape design,the thesis seeks the theoretical and technical support for rural sewage treatment in river valley areas,and establishes a bridge between rural sewage treatment technology and ecological landscape.Finally,combining theory with practice,taking the project of Lushi sewage treatment in Sanmenxia as an example,team completed the landscape design of ecological sewage purification display area in Zhangjiacun.The design focuses on presenting the application of internal sewage treatment technology and external landscape aesthetics.According to the main points of ecological landscape design and the theory of ecological edge effect,the local ecological system is effectively protected,and a rural domestic sewage purification display area with economic benefits is constructed.

Discussion on the Problems and Developing Trend of Construction of Sewage Treatment Plants in Small Towns

Existing problems of sewage treatment plants in small towns were summarized firstly,and then the developing trend of construction of sewage treatment plants in small towns was discussed from the aspects of project decision,site selection,design,processing technology and construction financing models. Finally,outlooks for its future development were proposed to provide reference for the construction of sewage treatment plants in small towns in future.

Influence Factors of Phosphorus Removal by Chemical Method in Sewage Treatment System

[Objective] The research aimed to study influence factors of phosphorus removal by chemical method in sewage treatment system. [ Method] In different reaction systems, removal effect of the phosphorus in sewage by dosing lime and influence of the constraint factor were stud- ied. [ Result] Lime precipitation method treating high-concentration phosphorus wastewater could not only decline cost of phosphorus removal by chemical method, but also reach better treatment effect under suitable stirring and precipitation conditions by controlling alkalinity and pH. Phosphor- us content of chemical sludge after treatment could reach 9% -12%, with higher recyclable value. E Conclusion] Lime method treating phosphorus- rich sewage was more economic than low-concentration phosphorus sewage, and had very great potential for recycling phosphorus.

Improved Monitoring Protocol for Evaluating the Performance of a Sewage Treatment Works Based on Sensitivity Analysis of Mathematical Modelling

Extensive historical data of a sewage treatment works are required by numerical models in order to simulate the biological processes accurately. However, the data are recorded mostly for daily operational purpose. They are basically not comprehensive enough to meet the modelling’s requirements. A comprehensive sampling protocol to accurately characterise the influent is required in order to determine all model components, which is very time-consuming and expensive. In a project of evaluating a sewage treatment works in Chongqing by using BioWin 4.1 for mathematical modelling, sensitivity analysis was conducted to determine the most critical parameters for process monitoring. It was found that influent characteristics, wasted sludge flow rate, water temperatures, DO levels of the biological tanks and five bio-kinetic parameters were the most influential parameters governing the plant performance. Therefore, apart from monitoring the effluent quality, regular checking of the afore-mentioned influential parameters can help examine the performance of a sewage treatment works. Moreover, operators of the sewage treatment works can conduct “what-if” analysis to determine how these most influential parameters can be adjusted to improve the treatment performance of the sewage treatment works.

Advances in Research of Characteristics and Removal of Microplastics in Sewage Treatment Plants

Microplastic pollution has become a worldwide issue.The discharge of sewage treatment plants(STPs)or wastewater treatment plant(WWTPs)is an important way for microplastics to enter the environment.This study reviewed the sources and occurrence characteristics(type,size,color and components)of microplastics in domestic and foreign sewage plants.It elaborated the removal principles of microplastics by primary,secondary and tertiary treatments.In addition,the removal effects of various treatment units and different processes on microplastics were summarized.In the future,the removal mechanism of microplastics in sewage treatment plants should be discussed in more depth,so as to further improve the removal rate of microplastics by optimizing and transforming traditional sewage treatment processes.Therefore,it is necessary to develop new technologies/processes specifically for the removal of microplastics and promote them to practical applications.

Greenhouse Gas Emissions from Sewage Treatment in China during 2000-2009

Based on the statistics from the China Statistical Yearbook(2000-2009) on environment and methods recommended by the IPCC,the amounts of greenhouse gas(GHG) emissions from domestic and industrial sewage treatment in China are estimated for the period of 2003-2009.CO2 emissions per capita from sewage treatment plants are also analyzed.The results show that the GHG emissions from sewage treatment plants increased steadily from 2003 to 2009;N2O emissions from domestic sewage are the major source of the total GHG emissions from domestic sewage;CH4 emissions from domestic sewage increase with the greatest speed;CH4 emissions from paper and pulp industry are the major source of industrial sewage emissions;CO2 emissions per capita increase constantly from 2003 to 2009.

Discussion on the Operation of Urban Domestic Sewage Treatment Facilities: A Case Study of Guangdong Province

Urban sewage treatment facility is an important ways to control polluted domestic water. The operation of urban sewage treatment facilities is good or not, and whether the effectiveness of pollutant emission reduction can be exerted play a significant role in reducing the pollution of living sources. Nowadays the operation of urban sewage treatment facilities is mainly evaluated by the load rate. However, due to the failure to fully implement the reformation of the rainwater and polluted water in Guangdong Province, the domestic sewage is mixed with rainwater during the rainy season and is included in the treatment of urban sewage treatment facilities. Therefore, it is not objective to evaluate the operation of sewage treatment facilities using only the load rate of sewage treatment. According to the situation of Guangdong Province, the load rates of COD, ammonia nitrogen and total phosphorus in domestic sewage and load rate of sewage treatment were included in the evaluation, and 20 urban sewage treatment facilities were selected as research objects. The operation situations and emission reduction benefits of urban sewage treatment facilities in different regions of Guangdong Province were roughly evaluated.

Pilot-scale Study on NCMBR Process for Upgrading of Sewage Treatment Plant in Industrial Park

A pilot-scale research was conducted on nanostructured ceramic membrane bio-reactor( NCMBR) for treatment of comprehensive wastewater from industrial park. The quality of the effluent water was stable and good. During stable operation,the COD,NH3-N and TP concentrations of the influent water were 147-475,42-23. 5 and 0. 65-0. 85 mg/L,respectively,and those of the effluent water were 147-475,0. 08-0. 82 and 0. 18-0. 26 mg/L,respectively,so the average removal rates of COD,NH3-N and TP were 82%,97% and 72%,respectively,meeting the standard for Class-A emissions of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant( GB18918-2002). In addition,the process has certain anti-impact capacity and ability to mitigate membrane fouling,meeting the objectives of upgrading and transformation. This study will provide reference for upgrading of existing sewage treatment plants.

Effect of Alkali Treatment on Heavy Metals Adsorption Capacity of Sewage Sludge

Sewage sludge is the promising raw material for biosorbent preparation. In this work, we evaluated the heavy metals adsorption characteristics of alkali treated sewage sludge (ATSS) by equilibrium studies. The adsorption isotherms were fitted with Langmuir and Freundlich models. Comparing with untreated sewage sludge, the total adsorption capacity (qm) of ATSS (prepared with 0.125 mol/L NaOH) for Cd, Pb, Ni, increased by 0.51, 0.70 and 0.32 mmol/g, respectively. When the NaOH concentration for ATSS preparation increased from 0.125 mol/L to 0.25 mol/L, the qm of ATSS for Pb decreased from 1.05 mmol/g to 0.84 mmol/g. However, when the NaOH concentration increased from 0.25 mol/L to 7.5 mol/L, it showed increasing trend. According to the IR spectra data, the adsorption effect of biosorbent for heavy metals was mainly due to the complexation of -N-H groups and -COOH groups.

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.

Isolation of a Microorganic Strain for the High Volume Degradation of Aniline Blue and Its Application in Natural Sewage Treatment

Aniline blue, one of the triphenylmethane dyes, is the most commonly produced and used of these dyes yet it is also the most dangerous and the most serious cause of pollution amongst them. An exploration of aniline blue degradation is likely to facilitate an understanding of the degradation mechanism for a range of related dyes. In this study, we managed to isolate a particular strain of microorganism, identified to be Lysinibacillus fusiformis N019a, which showed a significant capacity for aniline blue degradation in both laboratory tests and natural sewage treatment. In analysis aided by a UV-Visible spectrophotometer, we found that 96.7% of aniline blue had degraded within 24 hours under laboratory conditions. When treating natural sewage, 80.1% of the aniline blue was removed after just 16 hours. Further analysis has shown that Lysinibacillus fusiformis N019a has a strong resistance to Cu2+, Mn2+, Zn2+, and Pb2+. We also found that the degradation product of aniline blue by Lysinibacillus fusiformis N019a was of reduced toxicity to plants and microbes.