“1+X”证书背景下的环境专业“污水处理工”的实施探讨——以江阴职业技术学院为例

本文以江阴职业技术学院环境专业学生考取职业资格证书——"污水处理工"为例,探讨"政、校、企"三方在制定污水处理标准、开发污水处理课程和共同制定考核方案上的紧密合作。通过悉心联合指导和精心过程培训,不仅保证了证书的含金量,同时为地方污水处理企业输送了大量高素质的实用性人才,真正做到了服务企业,服务地方经济。

我国农村污水处理工艺分析及性能比较

随着我国经济的快速健康发展,农村中的水污染治理问题愈发严重,农村日常生活中的污水综合处理工艺是农村治理环境的重要环节,对农村污水处理技术工艺的基本分析及处理性能指标比较的深入研究也就显得尤为重要,这对研究改善农村污水处理工艺方法十分关键。本文针对此技术问题予以展开深入论述,从目前我国乡镇农村的污水处理角度引入,着重对我国乡镇农村等中小型地区污水消毒处理厂现有的主要技术工艺特点进行基本概述,引出对于污水消毒处理工艺的基本分析,并就此提出关于农村污水处理消毒工艺的技术建议。

Research Progress on Application of Constructed Wetland in Wastewater Treatment in China

Constructed wetlands as a wastewater eco-treatment technology has devel-oped for decades. Combining wastewater-treatment with water recycle in an efficient way, it plays an important role in water body restoration and ecological construction. Constructed wetlands with unique advantages have attracted intensive attention since it developed, and have been widely used in treatment of domestic sewage, industrial wastewater, and mine wastewater. In this paper, we summarized the clas-sification, composition, combination, operation mode and pol utant removal mecha-nism of constructed wetlands, as wel as the research progress on the application of constructed wetland in wastewater treatment at home and abroad. In addition, in view of the problems of using constructed wetlands to treat wastewater in China, corresponding solutions were put forward, including setting up system construction standards for constructed wetlands, developing the regulatory and enhancing tech-niques of nitrogen and phosphorus removal, and taking advantage of the unique features of constructed wetlands to improve and restore ecological environment.

Full-scale application of microbial agent on in-situ sludge reduction

The full-scale application of Tx-1, a multifunctional microbial agent, was carried out for 8 months in an anoxic/oxic（A/O） municipal wastewater treatment process. The results show that the Tx-1 dosed system can obtain good effluent characteristics while minimizing sludge production and energy consumption. The total phosphorus（TP） is lower than0. 5 mg/L in effluent without any chemical regent added. The discharged dry sludge per 10 000 m^3 wastewater Dwat decreases from 1. 4 to 0. 5 t. For per cubic meter wastewater, the air supply decreases from 6. 0 to 5. 1 m^3 and the electricity consumption decreases from 0. 412- 0. 425 kW·h to 0. 331 kW·h. The addition of Tx-1 can improve the substrate removal constant and decrease the microorganism growth yield coefficient of activated sludge. At the same time,the structure of the microbial community changes and the biodiversity increases by adding Tx-1. The abundance of polyphosphate accumulating organisms（PAO）, Comamonadaceae and Tetrasphaera, increased. Effective microbial agent is a potential way to combine in-situ sludge minimization with contaminants removal.

Advances in Energy-Producing Anaerobic Biotechnologies for Municipal Wastewater Treatment

Municipal wastewater treatment has long been known as a high-cost and energy-intensive process that destroys most of the energy-containing molecules by spending energy and that leaves little energy and few nutrients available for reuse, Over the past few years, some wastewater treatment plants have tried to revamp themselves as ＂resource factories,＂ enabled by new technologies and the upgrading of old technologies. In particular, there is an renewed interest in anaerobic biotechnologies, which can convert organic matter into usable energy and preserve nutrients for potential reuse. However, considerable technological and economic limitations still exist. Here, we provide an overview of recent advances in several cutting-edge anaerobic biotechnologies for wastewater treatment, including enhanced side- stream anaerobic sludge digestion, anaerobic membrane bioreactors, and microbial electrochemical systems, and discuss future challenges and opportunities for their applications. This review is intended to provide useful information to guide the future design and optimization of municipal wastewater treatment processes.

“Co-culture Engineering”for Enhanced Phytoremediation of Metal Contaminated Soils

A co-culture of two plant materials, Astragalus sinicus L., a leguminous plant with concomitant nodules, and Elsholtzia splendens Naki-a Cu accumulator, along with treatments of a chelating agent (EDTA), root excretions (citric acid), and a control with E. splendens only were used to compare the mobility of heavy metals in chelating agents with a co-culture and to determine the potential for co-culture phytoremediation in heavy metal contaminated soils. The root uptake for Cu, Zn, and Pb in all treatments was significantly greater (P ＜ 0.05) than that of the control treatment. However with translocation in the shoots, only Cu, Zn, and Pb in plants grown with the EDTA treatment and Zn in plants cocropped with the A. sinicus treatment increased significantly (P ＜ 0.05). In addition, when a co-culture in soils with heavy and moderate contamination was compared, for roots in moderately contaminated soils only Zn concentration was significantly less (P ＜ 0.05) than that of heavily contaminated soils, however, Cu, Zn, and Pb concentrations of shoots were all significantly lower (P ＜ 0.05). Overall, this 'co-culture engineering' could be as effective as or even more effective than chelating agents, thereby preventing plant metal toxicity and metal leaching in soils as was usually observed in chelate-enhanced phytoremediation.

Fuzzy Control of Nitrate Recirculation and External Carbon Addition in A/O Nitrogen Removal Process

Nitrogen and phosphorous concentrations of effluent water must be taken into account for the design and operation of wastewater treatment plants. In addition, the requirement for effluent quality is becoming strict. Therefore, intelligent control approaches are recently required in removing biological nutrient. In this study, fuzzy control has been successfully applied to improve the nitrogen removal. Experimental results showed that a close relationship between nitrate concentration and oxidation-reduction potential (ORP) at the end of anoxic zone was found for anoxic/oxic (A/O) nitrogen removal process treating synthetic wastewater. ORP can be used as online fuzzy control parameter of nitrate recirculation and external carbon addition. The established fuzzy logic controller that includes two inputs and one output can maintain ORP value at - 86 mV and - 90 mV by adjusting the nitrate recirculation flow and external carbon dosage respectively to realize the optimal control of nitrogen removal, improving the effluent quality and reducing the operating cost.

吉林省人民政府关于印发2010年吉林省主要污染物总量减排计划的通知

吉政发[2010]17号各市(州)人民政府,长白山管委会,各县(市)人民政府,省政府各厅委办、各直属机构:现将《2010年吉林省主要污染物总量减排计划》印发给你们,请认真遵照执行。

Sorption Kinetic Analysis for the Removal of Copper(Ⅱ) by Using Biofilm

The biosorption of copper(Ⅱ) ions onto biofilm was studied in a batch system with respect to the temperature, initial pH value and biofilm sorbent mass. The biomass exhibited the highest copper(Ⅱ) sorption capacity under the conditions of room temperature, initial pH value of 6.0 and the sorbent mass 8 g. The experimental data were analyzed using four sorption kinetic models, the pseudo-first order, the Ritchie second order, the modified second order and the Elovich equations to determine the best-fit equation for the sorption of metal ions onto biofilm. Comparing with the sum of squared-errors, the results show that both the Ritchie second order and modified second order equations can fit the experimental data very well.

Degradation of 4-Chlorophenol Solution by Synergetic Effect of Dual-frequency Ultrasound with Fenton Reagent

4-Chlorophenol (4-CP) solution was treated by dual-frequency ultrasound inconjunction with Fenton reagent, and obvious improvement in the 4-CP degradation rate was observedin this advanced oxidation process. Experimental results showed that ultrasonic intensity,saturating gas and pH value affected greatly the 4-CP removal rate. Among four different saturatinggases (Ar, O_2, air and N_2), 4-CP degradation with Ar-saturated solution was the best. However, inthe view of practical wastewater treatment, using oxygen as the saturating gas would be moreeconomical. The addition of Fenton reagent followed the first-order kinetics and increased the 4-CPdegradation rate. The 4-CP removal rate increased by around 126% within 15 min treatment. Thesynergetic effect of dual-frequency ultrasound with Fenton reagent on 4-CP degradation was obviouslyobserved.

Comparison of heavy metal removal efficiencies in four activated sludge processes

The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. Significant differences of heavy metal removal efficiencies were observed among four activated sludge processes. The removal efficiency for As(75.5%) in the oxidation ditch(OD) process is significantly higher than that in the conventional activated sludge(CAS) process(38.6%) or sequencing batch reactor(SBR) process(51.4%). The mean removal efficiencies for Cu and Ni in the OD process are 90.5% and 46.7%, respectively, while low mean removal efficiencies are observed for Cu(69.9%) and Ni(16.5%), respectively, in the SBR process. The removal efficiencies for Cu and Ni in the OD process are significantly higher than those in the anaerobic-anoxic-oxic(A2-O) process. These results highlight the differences of removal efficiencies for heavy metals in different processes and should be considered when selecting a wastewater treatment process.

CH_4 emissions and reduction potential in wastewater treatment in China

The treatment of domestic and industrial wastewater is one of the major sources of CH_4 in the Chinese waste sector. On the basis of statistical data and country-specific emission factors, using IPCC methodology, the characteristics of CH_4 emissions from wastewater treatment in China were analyzed. The driving factors of CH_4 emissions were studied, and the emission trend and reduction potential were predicted and analyzed according to the current situation. Results show that in 2010, CH_4 emissions from the treatment of domestic and industrial wastewater were0.6110 Mt and 1.6237 Mt, respectively. Eight major industries account for more than 92% of emissions, and CH_4 emissions gradually increased from 2005 to 2010. From the controlling management scenario, we predict that in 2020, CH_4 emissions from the treatment of domestic and industrial wastewater will be 1.0136 Mt and 2.3393 Mt, respectively, and the reduction potential will be 0.0763 Mt and 0.2599 Mt, respectively.From 2010 to 2020, CH_4 emissions from the treatment of domestic and industrial wastewater will increase by 66% and 44%, respectively.

Kinetics of aerobically activated sludge on terylene artificial silk printing and dyeing wastewater treatment

Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kinetics pa-rameters determined from experiment were applied to evaluate the biological treatability of wastewater. Experiments showed that COD removal could be divided into two stages, in which the ratio BOD/COD (B/C) was the key factor for stage division. At the rapid-removal stage with B/C>0.1, COD removal could be described by a zero order reaction. At the mod-erate-removal stage with B/C<0.1, COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (KS) were 0.0208-0.0642 L/(gMLSS)h and 0.44-0.59 (gCOD)/L respectively at 20 C-35 C. Activation energy (Ea) was 6.05104 J/mol. By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater. But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater, such as papermaking, beer, phenol wastewater, etc. The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up and efficient operation of TPD wastewater treatment.

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; N20 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.

In Vitro Biossay for Assessing Estrogenic Activity of Sewage Treatment Works

The estrogenic activity of influents and effluents of five municipal sewage treatment works （STWs） in Nanjing was investigated. The water samples were enriched by solid phase extraction, then eluted with different polar solvents, and f＇mally three fractionated extracts were obtained. Estrogen receptor recombinant yeast screen was used to evaluate the estrogenic activity of individual fractionated extracts and their mixture. The results show that the influents and effluents of the two STWs mainly receiving industrial wastewater have no obvious estrogenic activity, and the water samples from the other three STWs mainly receiving domestic wastewater show different degrees of estrogenic activity. The total estrogenic concentration ranged from 171. 52 ng/L EEQ （E2 - equivalent concentration） to 1 008.37 ng/L EEQ in the influents, and from ND （not detected） to 36.3 ng/L EEQ in the effluents. By comparing the results of different fractionated extracts, the methanol and dichloromethane extracts of the water samples show higher estrogenic activity, while the hexane extracts very low. The （xeno）estrogens from domestic wastewater could be removed obviously by activated sludge treatment units. However, the effluents of STWs in Nanjing still have chemical contaminants capable of binding to estrogen receptors.

Experimental study on the degradation of Rhodamine B by hydrodynamic cavitation technique

Hydrodynamic cavitation is a new technique in wastewater treatment processes. The degradation of Rbodamine B was studied on a 220 liters hydrodynamic cavitation setup using multiple hole orifice plates in this paper. The experimental results showed that Rhodamine B was really decomposed by hydrodynamic cavitation. Some factors influencing degradation effect i.e. geometric parameters and operation conditions also were discussed. It was concluded there was the optimal ratio of total area of holes to crosssectional area of the pipe and the rate constant increased with a reduction in the value of the modified cavitional number.

CANON Process for Nitrogen Removal from Effluents of Municipal Sewage Treatment Plants

The feasibility and performance of nitrogen removal from municipal sewage were investigated through the completely autotrophic nitrogen removal over nitrite (CANON) process in a continuous reactor. CANON process was successfully started up with the transformation of nitrogen into gas by mass-balance analysis. For the synthetic waste-water (up to 480 mg NH4+-N/(L·d)), removal rates of the ammonia nitrogen and total nitrogen (TN) were about 80% and 55%, respectively, at 1.25 h hydraulic retention time (HRT). For the secondary effluent of municipal sewage, the effluent concentrations of NH4+-N and TN were below 5 mg/L and 9 mg/L, respectively. It is in accordance with the water quality standard for scenic environment with the reuse of urban recycling water (GB/T 18921-2002).

Bioremediation potential of spirulina:toxicity and biosorption studies of lead

This study examines the possibility of using live spirulina to biologically remove aqueous lead of low concentration (below 50 mg/L) from wastewater. The spirulina cells were first immersed for seven days in five wastewater samples containing lead of different concentrations, and the growth rate was determined by light at wavelength of 560 nm. The 72 h-EC50 (72 h medium effective concentration) was estimated to be 11.46 mg/L (lead). Afterwards, the lead adsorption by live spirulina cells was conducted. It was observed that at the initial stage (0–12 min) the adsorption rate was so rapid that 74% of the metal was bio- logically adsorbed. The maximum biosorption capacity of live spirulina was estimated to be 0.62 mg lead per 105 alga cells.

Discussion on nitrogen and phosphorus removal process characteristics of improved oxidation ditch

In order to enhance efficiency of the nitrogen and phosphorus removal of sewage treatment plant, Taking Wu Long kou sewage treatment plant project in Zhengzhou as an example, this article introduces the structure, the working principle, the craft character, as well as the problems existed in the practical application of the improved oxidation ditch, and raises some corresponding processing countermeasures. Looked from the running situation of Wu Long kou sewage treatment plant, the improved oxidation ditch have certain advantages in city sewage treatment, such as high organic removing efficiency, good removing effect of nitrogen and phosphorus, low investing expenses and operating cost and so on. It is a craft that is worth promoting in urban sewage treatment.

Behavior of Millstone Masonry Vaults Strengthened by Composite Materials

Sewerage systems first appeared in Paris in the middle of 19th century. Even if the majority of structures are still in working order, their general state will deteriorate inexorably, and as reconstruction is not always possible for cost and social impact reasons, rehabilitation is a solution adopted by many clients. It is necessary to resort to new rehabilitation techniques. Reinforcement by bonding composite materials has many advantages compared to other techniques. The objective of the experimental campaign presented in this paper is to study the addition of a lining by means of mortar reinforced by thin composite materials so as to restore masonry structures. To that purpose, crushing tests on masonry vaults have been carried out. The application of a lining made of mortar reinforced with composite materials has allowed increasing the breaking load and delaying the occurrence of the first cracks. This article presents the characterization of the materials. Moreover, the results of the breaking tests applied to masonry vaults are shown in this paper. A comparison with a traditional type of rehabilitation by a 6 cm-thick shotcrete lining will be performed.