Pyrolysis of refuse derived fuel (RDF) has great potential for energy recovery from municipal solid waste (MSW), while chlorine-related plastics issue was one major barrier for scale up. After screening out plastics, the RDF pyrolysis and char products combustion were evaluated in lab and pilot scales. Thermogravimetry with Fourier transform infrared spectroscopy results suggest that the main RDF pyrolysis reaction occurred in 190-410 degrees C, involving decomposition, decarboxylation, demethylation, and dehydration reactions, with CO2, CH4, H2O, CO, and organic compounds as the main gaseous products. Impacts of temperature and residence time on char yield and proximate composition were evaluated in lab, and a lower temperature was favored. The pilot-scale char had a comparable proximate composition to the lab-scale ones, but a lower heating value, lower H/C ratio, higher O/ C ratio, which may due to different dominant reaction pathways during pyrolysis: apparent demethanation versus dehydration. Thermogravimetry data infers that the combustion performance of pilot-scale char, including combustion stage, weight loss, and kinetic parameters, were close to chars made in lab. Pilot-scale combustion tests show relief of flue gas pollution after upgrading RDF to char, while particulate matter and heavy metals were still main concerns. Lab-and pilot-scale investigations highlight scale up of plastics-free RDF pyrolysis and combustion as a promising and economic alternative for materials and energy recoveries from MSW.

Non-point source (NPS) pollution has a complex formation mechanism, and identifying its primary controlling factors is crucial for effective pollution treatment. In this study, the Baixi Reservoir Watershed, characterized by low-intensity development, was selected as the study area. A new methodology combining the Soil and Water Assessment Tool (SWAT) with the Random Forest (RF) algorithm was proposed to comprehensively identify the primary controlling factors of NPS pollution and analyze the interaction between factors. The results of the validated SWAT model showed that the annual intensity of total nitrogen (TN) load range was 0.677–11.014 kg ha−1 yr−1, and the total phosphorus (TP) load per unit area range was 0.020–0.110 kg ha−1 yr−1. Loads of sediment, TP, and TN exhibited significant seasonal variations, particularly in the Baixi basin, where sediment yield had the highest absolute change rate, with a value of up to 232.26. Random Forest models for TN and TP displayed high accuracy (R2 > 0.99) and robust generalization ability. Fertilization, sediment yield, and terrain slope were identified through RF models as the primary factors affecting TN and TP. By graphing partial dependency plots (PDPs) based on the results of the RF models to analyze the interaction between factors, the findings suggest a strong synergistic effect of two combined factors: fertilization and sediment yield. When fertilizer application exceeds 15 kg ha−1 yr−1 and sediment yield exceeds 3 kg ha−1 yr−1, there is a sharp increase in nitrogen and phosphorus load. Through the identification and analysis of the primary controlling factors of NPS pollution, this study provides a solid scientific foundation for developing effective watershed management strategies.

Urban rivers were often cut off during engineering construction in regions with dense river network, causing severe deterioration of the river eco-system. Due to little research conducted on the blocked river remediation, this study applied integrated engineering measures including aeration, planted floating beds, fiber biofilm carriers, and microbial reagents to remediate a blocked river in-situ. The concentrations of NH3-N, total phosphorus (TP), and CODMn of the blocked river were markedly reduced, with removal efficiencies of 50.5-94.7%, 15.8-78.2%, and 30.4-78.7% after 3-months remediation, respectively. Negative correlations were found between NH3-N and temperature, pH, between TP and pH, probably due to season and/or pH dependent biological processes. Positive correlation between CODMn and dissolved oxygen suggests the efficiency of artificial aeration in COD elimination. The biofilms developed on fibers showed temporal and spatial variations in quantity and extracellular polymeric substances (EPS) composition. The biofilm EPS was dominated by humic acid-like compounds with low freshness, while the dissolved organic matter in the river mainly consisted of aromatic proteins and fulvic acid-like compounds with high freshness which may attributed to the microbial reagents. No secondary pollution from sediment was observed. Results suggest integrated ecological remediation as a feasible strategy for the blocked river remediation.

Conventional bioretention filters lack satisfactory performance in nitrogen removal. In this study, we used a mixture of cultivated soil and river sand as the bioretention filter to remove nitrogen pollutants from simulated rainwater runoff. To improve its permeability and nitrogen removal performance, both activated carbon and ceramsite were used as additives. The nitrogen removal processes and its mass accumulation in the modified bioretention filters were studied. The contribution of adsorption and biotransformation processes, together with the effects of percolate rate on nitrogen removal performance was explored. The results showed that an activated carbon layer in the bioretention filters could obviously improve nitrogen removal efficiencies, but its location made no significant difference in nitrogen removal performance. Bioretention filters modified with 20% of ceramsite could achieve the optimal percolate rate and nitrogen removal efficiencies. At given conditions, the average removal efficiencies of ammonium nitrogen (NH3-N), nitrate-nitrogen (NO3-N), and total nitrogen (TN) by the modified bioretention filter reached 80.27%, 41.48%, and 59.45%, respectively. During the leaching processes, organic nitrogen originated in the filter materials can be mineralised into NH3-N, then be denitrified and completely removed in the anaerobic environment under flooding conditions. Biotransformation in the modified bioretention filters caused a reduction of NH3-N removal efficiency by 15.41% and an increase of NO3-N removal efficiency by 31.03%. The modified bioretention filter can withstand a long-term operation. Compared with NO3-N and TN, the pollutant of NH3-N in rainwater runoff is not easy to form a mass accumulation in the modified bioretention filter.Highlights The modified bioretention filter showed high percolation rate and nitrogen removal.Hydraulic residence time is a critical design parameter to achieve nitrogen removal.NH3-N is not easy to form a mass accumulation in the filler media as NO3-N.Biodegradation increased NO3-N removal efficiency by 31.03% at given conditions.

The Soil Water Assessment Tool (SWAT) was used for exploring the sources and retention dynamics of phosphorus nutrient in the river system of the Yong River Basin, China. The performance of the SWAT model was assessed. The retention dynamics of phosphorus nutrient in the river continuum and the factors contributing to those patterns were studied. The results showed that an average of 1828 tons of TP entered the river network of the Yong River Basin annually and in-stream processes trapped 1161 tons yr(-1) of TP in the watercourse, which accounted for 63.5% of the annual TP inputs. The TP retention rates in the river network ranged from 3.08 to 63.43 mg m(2) day(-1). An average of 666.9 tons of TP was delivered from the estuary to the East China Sea annually. The unit area riverine exports of TP ranged from 102.21 to 244.00 kg km(-2) yr(-1). The river network is a net sink for TP and is going through a phosphorus accumulation phase. The results confirm that the river system has a considerable phosphorus retention capacity that is highly variable on a spatiotemporal scale. Because of the cumulative effect of continued phosphorus removal along the entire flow path, the retention fractions of phosphorus removed from all streams at the basin scale is considerably higher than that of an individual river portion. The variations of hydrological regimes, water surface area, unit area inputs of phosphorus, and the concentrations of suspended sediments have a great influence on phosphorus retention.

"环境化学"是高等院校本科专业环境科学与工程课程体系中具有桥梁作用的一门专业基础课.随着工程教育专业认证的进一步深入,基于成果导向的教育理念,重新确立"环境化学"课程的教学目标,并从教学内容、教学方法及考核体系等方面进行了教学改革探索,以此完善教学大纲,旨在增强学生主动学习的积极性,提高学生综合应用所学知识解决实际工程的能力,使这门传统的理论课程能够满足环境工程专业本科生的毕业要求,支撑培养目标的达成.

为定量评估城市低影响开发的环境效应,以宁波海绵城市建设试点区为例,通过构建研究区SWMM模型,研究不同降雨强度下16种低影响开发情景方案对雨水径流量、氨氮(NH3-N)、硝态氮(NO3-N)和总氮(TN)等氮污染物控制的效应.结果表明,生物滞留池、透水铺装单项技术及其组合方案对雨水径流量的削减率分别介于3.41％～41.83％、1.08％～27.77％和5.59％～51.13％;低影响开发对各种氮污染物的削减作用与降雨强度、设施种类及面积有关,生物滞留池对径流量和氮污染物的控制效应强于透水铺装;在小降雨事件(<10 mm)中,低影响开发技术对NH3-N、NO3-N和TN均具有较高的控制效率,当降雨强度增大时控制效率较低,但污染物的削减总量较大;当研究区海绵设施面积为7.08 km2时,NH3-N、NO3-N和TN的污染负荷削减率分别高于28.62％、32.42％和24.82％.

The pollution of rainwater runoff in urban areas can cause nutrient enrichment and eutrophication in receiving waters. To explore the pollution characteristics of rainwater runoff in Ningbo, eight sampling campaigns were carried out during rainfall events from 2009 to 2019. Samples of rainwater runoff were collected from underlying surfaces of roofs, squares, grassland, main roads, and the roads in commercial streets and residential districts. The concentrations of runoff pollutants, their sources and correlations, and first flush effects were studied using frequency statistical analysis and correlation analysis. The average event mean concentrations of the chemical oxygen demand (COD), ammonia nitrogen, total nitrogen, total phosphorus, and total suspended solids (TSS) in the rainwater runoff in Ningbo were in the ranges of 23.88-102.31, 0.40-1.69, 3.41-8.71, 0.09-0.50, and 37.6-323.4 mg·L-1, respectively. Apart from the square surfaces, the COD and total nitrogen pollution of the underlying surfaces was severe. The ammonia nitrogen concentrations from the roof, commercial street, and residential district surfaces were significantly higher (P<0.05) than those from the square, grassland, and main road surfaces. The concentrations of total phosphorus from the commercial street, main road, and grassland surfaces were significantly higher (P<0.05) than those of the other underlying surfaces. The correlations of TSS with COD, ammonia nitrogen, and total phosphorus showed that the pollutants and TSS have the same original sources in roof, square, main road, and commercial street runoff, while ammonia nitrogen and total nitrogen have the same original sources in runoff from grassland and residential areas. Under the meteorological conditions of light and moderate rain, the first flush effects of ammonia nitrogen in the runoff of roofs and grassland were observed clearly, whereas this was not the same for the pollutants of total nitrogen and total phosphorus in the residential area, main road, and square runoff.

Calcium ion is an important cation influencing the binding of recalcitrant organic contaminants with activated sludge during wastewater treatment process, but there is still unknown about its role in amphoteric fluoroquinolones binding. Binding experiments show that Ca2+ markedly inhibited binding of ciprofloxacin (CIP) onto sludge, causing 7-203 times of CIP release. Multi-spectroscopic examinations indicate that tryptophan-like and tyrosine-like proteins in extracellular polymeric substances (EPS) were dominant components for CIP binding by static quenching and forming CIP-proteins complexes. Addition of Ca2+ into EPS and CIP binding systems induced increase of association constants (from 0.024-0.064 to 0.027-0.084 L/mu mol) and binding constants (from 0.002-0.039 to 0.012-0.107) and decrease of binding sites number (from 0.893-2.007 to 0.721-1.386). Functional groups of EPS and secondary structure of proteins were remarkably changed upon reactions with CIP and Ca2+. Calcium ion interacted with EPS and CIP binding system in two distinct ways: Ca2+ shielded Cdouble bondO in amide I in EPS for CIP binding, whereas strengthened binding between CIP and functional groups including Cdouble bondO in carboxyl groups in extra-microcolony polymers and Osingle bondH in extra-cellular polymers by forming ternary complexes. Cation competition for Cdouble bondO in amide I is responsible for Ca2+ induced CIP release from the sludge. Results suggest the highly potential release of CIP from high saline wastewater and cation-conditioned sludge which needs further monitoring and evaluation. (C) 2020 Elsevier B.V. All rights reserved.

为定量探讨SWAT模型在土地利用方式对面源磷污染影响研究中的适用性,以甬江流域为研究区,构建流域2010年至2014年的SWAT水文水质模型,从水文响应单元的空间尺度上进行了分析研究.结果表明:模型在开展大中流域尺度,长时间序列的土地利用方式对面源磷污染影响的研究中表现良好;流域内林地、建设用地、耕地、园地年均产流深度分别为588.05、729.52、624.26、608.05 mm,产沙年均单位负荷分别为10.09、0.90、44.68、13.29 t·hm-2;总磷年均单位负荷分别为1.42、0.35、9.81、1.82 kg· hm-2.产流深度、产沙单位负荷与总磷单位负荷之间的一元线性回归模型表明:产流、产沙和面源磷之间存在明显的线性关系,且各土地利用方式产沙和磷(R2=0.83～0.88,P＜0.001)之间的一元线性回归模型预测能力均高于产流和总磷(R2=0.63～0.68,P＜0.001),表明了面源磷流失的主要载体为泥沙.此外,不同类型土地利用方式下磷输出空间差异性也十分显著,林地在坡度级别为6级时磷流失是2级时的6.90倍;土壤类型RGd(不饱和疏松岩性土)在坡度2级下磷流失是ACu(腐殖质低活性强酸土)的1.15倍,而在6级下是1.42倍.

In this study, the concentrations of 4-nonylphenol (4-NP), 4-tert-octylphenol (4-t-OP), and bisphenol A (BPA) in the water column of the Yong River were investigated and found to be in the range of 140-3948, 6-828, and 15-1415 ng L-1, respectively. A fate and transport model coupled with the Water Quality Analysis Simulation Program (WASP) was developed. After model calibration and validation, the distributions of 4-NP, 4-t-OP, and BPA in the Yong River were modeled for the duration of 2015. The total contaminant loads from the upstream boundary, four tributaries and two wastewater treatment plants were determined to be 2318 kg yr(-1) for 4-NP, 506 kg yr(-1) for 4-t-OP, and 970 kg yr(-1) for BPA. Both measured and modeled results reported higher concentrations of the selected contaminants near river confluences and at the outfalls of the wastewater treatment plants. Peak concentrations were found to always appear in months with relatively reduced precipitation. The influences of adsorption and degradation on the dissolved concentrations of the selected chemicals were also modeled. The combined effects of adsorption and degradation were found to reduce dissolved concentrations of 4-NP, 4-t-OP, and BPA by 17.9%, 30.7%, and 12.1%, respectively. Adsorption was shown to reduce 4-NP concentrations in the Yong River more than degradation. Conversely, adsorption and degradation caused almost equal reductions in the dissolved concentrations of 4-t-OP and degradation caused larger decreases than adsorption in the dissolved concentrations of BPA. (C) 2017 Elsevier Ltd. All rights reserved.

Interaction of ciprofloxacin with the activated sludge of the sewage treatment plant is of importance for the ciprofloxacin migration and risk control. More than 96.0% ciprofloxacin was removed through the sludge adsorption. The sludge surface charge varied little with ciprofloxacin since most ciprofloxacin was dissociated into the neutral one. No obvious shift was observed for the soluble carbohydrate concentration and composition with the addition of ciprofloxacin, indicating the weak interaction between the carbohydrates and ciprofloxacin. The introduction of ciprofloxacin resulted in a reduction of the soluble protein concentration, a marked increase of the extracellular protein fluorescence intensities, and a dramatic emergence of new extracellular proteins. The alteration of the proteins highlights the strong interaction between the extracellular proteins and ciprofloxacin, and the consequent integration of certain soluble proteins and original unextractable inner layer extracellular proteins into the extractable extracellular proteins. Different types of interactions are suggested to dominate between the extracellular proteins and the differently dissociated ciprofloxacin.

The essay was aimed at exploring the characteristics of prokaryotic diversity and its relation with the properties of the sedi-ments at the estuary of Hangzhou Bay. The DNA sequences of 16S rRNA gene at the V3-V4 region were analyzed with the Illumina Miseq high-throughput sequencing platform. The results showed that 1118 genera, 688 families, 419 orders, 210 classes and 65 phyla were found in the 13 samples, and the average of Shannon-Wiener diversity index reached 9. 72. The dominant prokaryotes were Pro-teobacteria, Choloroflexi, Bacteroidetes at the phylum level, with the relative abundance of Proteobacteria being the highest among those of the 13 samples. The abundances of the Firmicutes in samples from the south bank of Hangzhou Bay were higher than that of the north bank. Compared to the Shangyu industrial zone, samples from Jinshan Industrial Zone could be found higher abundance ofβ-Proteobac-teria but the lower abundance ofγ-Proteobacteria. There was significant correlation between the abundances of Bacteroidetes andβ-Pro-teobacteria and total organic carbon (TOC), and the abundances of Bacteroidetes, Actinobacteria and Acidobacteria were significantly impacted by pH. The contents of Fe and As were significantly correlated with the abundances ofα-Proteobacteria, GN04 and Cholorobi respectively, while Mn and Cu were significantly correlated with GN04 and Spirochaetes, respectively.Therefore, the characteristics of prokaryotic diversity in the sediments at the estuary of Hangzhou Bay could be analyzed by the method of high-throughput sequencing. Furthermore, the relationships between the environmental factors and the prokaryotic diversity could be illustrated.

In recent years, the Chinese government has strengthened its efforts in surface water protection and restoration through strict policies and heavy investments. A clear understanding of the impacts of land use on water quality is necessary in order to ensure an effective and efficient implementation of the ongoing surface water restoration program in China. To this end, four small watersheds (less than 5000 ha) in southeastern China, which have clear gradients in the intensities of agriculture (17.0-45.4%), forest (35.2-73.6%) and built-up area (3.3-8.5%), were investigated regarding the impacts of land use on water quality. In addition to the general water quality indices, characteristic components derived by fluorescence excitation-emission matrices (FEEMs) coupled with parallel factor analysis (PARAFAC) were employed to explore a more accurate association between land use and water quality. The results show that agricultural intensity has significant effects by elevating the concentrations of dissolved organic carbon (DOC, an approximate six-fold increase) and total phosphorous (TP, an approximate four-fold increase) in the surface waters. A total of five PARAFAC components representing terrestrial (three components) and protein-like (two components) substances were identified. The PARAFAC results indicate that land-use patterns affected the dissolved organic matter (DOM) in the aspects of both amount and composition. The intensity (R.U.) of the terrestrial components showed a strong correlation (r(2)= 0.95, p= 0.01) with agricultural land percentage. Moreover, although the proportion of built-up area varies with a relatively small range, a protein-like component could predict its impact with excellent sensitivity (r(2)= 0.94, p=0.02), where as the general water quality indices were incapable of predicting the impact due to their multiple sources. The results of this study demonstrate that the FEEMs-PARAFAC technique provides an inexpensive and effective tool for policy makers to overcome the insensitivity of general water quality indices, particularly for the restoration of watersheds with complex land-use patterns. (C) 2018 Elsevier B.V. All rights reserved.

[Objective] Concerning the shortage in the extraction of plain river network based on DEM,we adopted a new method to extract plain river network and to provide basis for automatic drainage extraction method.[Methods] Using Acr Hydro Tools and SWAT,the river network of Yaojiang river basin in Ningbo City was extracted in DEMs with different contour.The extracted total area of the basin and total length of rivers were used as the main index of quantitative analysis.Relative error formula,matching error formula of river network and Visual Similarity Duplicate Image Finder software were used for comprehensive evaluation and error analysis.[Results] With the help of the real river network,the extracted results based on Neat DEM by Acr Hydro Tools and SWAT were very bad.However,the extracted river network,basin and total basin export based on Adjacent DEM were consistent with the actual,and the precision and similarity were also high.[Conclusion] Extracting basin and river network with Acr Hydro Tools and SWAT are all desirable,but the SWAT is more convenient.The quality of river network extraction is dependent on DEM contour and also dependent on whether the DEM is tangent with the total basin export or not.

微生物是城市内河生态系统的重要组成部分,其多样性与水环境密切相关.以16S rRNA基因作为原核细菌分子标记,应用PCR-DGGE、定量PCR、克隆和测序方法,分析经生态修复工程处理后不同污染程度的城市内河水体细菌多样性特征.结果表明:生态修复工程明显提高了污染程度较低水体总氮(TN)、总磷(TP)和化学需氧量(CODMn)的消减能力,影响着城市内河水体中细菌群落的组成和含量,且随时间和空间不同而不同;生态修复工程显著地提高了重度污染水体细菌的含量;冗余分析(RDA)表明,水体中细菌群落组成与CODMn、TP和溶解氧(DO)等指标密切相关.

To understand the pathogenic bacteria abundance in urban rivers is of significance to ensure the urban ecological security. The quantity of enteric pathogenic bacteria in six water samples collected from the main rivers in Ningbo city were determined using re-al-time Polymerase Chain Reaction ( qPCR) .The correlationship between the pathogenic bacteria abundance and water properties was analyzed.The results showed that the numbers of enteric pathogenic bacteria in the river of Zuguanshan, Sujia, Nanbei, Houxi, Shi-weijia and Zhiluo were 3.34 ×105 , 1.47 ×105 , 4.68 ×105 , 1.75 ×106 , 9.65 ×106 and 1.33 ×106 cell/L water, respectively.The quantity of enteric pathogenic bacteria was positively related to dissolved oxygen in water, and negatively related to total nitrogen (TN), ammonia (NH4+-N), turbidity, total phosphate (TP), CODMn, Chla and electrical conductivity (EC).It has no relation with transparency, temperature and pH in water.

Distributions of nonylphenol, octylphenol and bisphenol A in water columns and sediments at ten sample collecting stations in Ningbo Inner River were investigated using the method of high performance liquid chromatography coupled with ultrasonication extraction and solid phase extraction. It was found that NP and BPA are widely scattered in Ningbo Inner River, and the detection rates of both OP in water columns and sediments were about 50%. The highest concentrations of NP, OP and BPA were measured as 4.516μg·L-1, 0.384μg·L-1, 1.594 μg·L-1 in the river water samples, and 0.811 μg·g-1, 0.139 μg·g-1, 0.223 μg·g-1 in the sediments samples, respectively. The concentrations of the three phenolic endocrine disruptors were found to be higher in Jiangbei River, Ningda River and Hucheng River, and relatively lower in Chengwan Reservoir, Yao River and Houxi River, and with the higher concentration in winter than in summer. There was also a positive concentration correlation, although insignificant, among the three pollutants in water columns and sediments, The result shows that exposure to the phenolic environmental endocrine disruptors may risk ecological aquatic organisms in Ningbo Inner River.

采用《水质氰化物的测定容量法和分光光度法》(HJ 484-2009)中的方法3(异烟酸—巴比妥酸分光光度法)测定水中氰化物时,在弱酸性条件下生成氯化氰,系统稳定性较差,需要快速操作,对实验技能要求高.基于原方法显色机理,提出了针对该方法的改进措施:提高氢氧化钠吸收液浓度;增加显色剂浓度,减少其加入体积;将加入磷酸盐缓冲溶液改为直接加入粉末状无水磷酸二氢钾,使得水中氰化物与氯胺T在中性条件下作用生成氯化氰,再进一步反应显色.改进后的方法稳定性好、检出限低、操作简便,对实际样品的测定结果令人满意.