污、废水管路堵塞解决方案在工程中的应用

为解决民用建筑中存在排水倒灌现象,我们分析了排水堵塞倒灌的成因,提出污、废水倒灌报警应急系统,采用一种肉眼可观察、可传递信号并报警、堵塞后自动排出的系统,旨在建立一种集约高效的污、废水管路堵塞排水系统,在不影响业主使用的情况下,实现在线监测、报警及应急自动处理;提出对设计排水系统的取值要求,对施工管理与验收要求,对业主使用要求等。

超高层建筑污、废水排水系统设计探讨

超高层建筑与普通高层建筑排水系统相比较,主要存在排水系统流态复杂、管道内压力波动大、排水流速大、排水管振动和噪音大等特点,这些情况实际工程设计中若不加以重视可能会产生比较严重的后果,结合国内部分工程案例对150 m以上的超高层建筑排水系统的设计进行分析比较,提出一些设计中的要求和注意事项。

Water Pollution Situation and Impacts in Rural China

With the development of national economics, water pollution is becoming a critical problem in rural China. This research presented a brief view of water pollution situation in rural areas of China in terms of water shortage, water-pollutant sources, eutrophication of water bodies and pollution development in temporal scale. Analysis was conducted on the negative effects of water pollution on human health, agricultural plantation and animal husbandry. Subsequently, some suggestions were proposed for wastewater treatment in rural areas.

垃圾焚烧发电厂供排水及处理系统设计分析

焚烧处理已成为我国垃圾处理的主要方式,并形成了“焚烧为主,填埋托底”的垃圾终端处理格局。“十三五”收官与“十四五”起舞之年,对垃圾焚烧发电厂给水与给水处理系统、污废水排水及其处理系统的设计进行了系统的分析。预计在“十四五”期间,污水、生活垃圾、污泥、餐厨垃圾等协同处理模式及“去工业化”“邻避”化“邻利”的设计理念将得到深入的发展与践行。

CHARACTERISTICS OF THERMOPHILIC ANAEROBIC ACIDOGENESIS OF STARCH WASTEWATER

Acidogenic dissimilation of synthetic starch wastewater (1 000～10 000 mg COD·L -1 ) was studied in a thermophilic (55 ℃) upflow anaerobic sludge blanket (UASB) reactor.The production of volatile fatty acids (VFA) was proportional to the chemical oxygen demand (COD) loading rate.The yield of VFA was around 0.28 g VFA/g COD over the COD loading rate from 1.25 to 30 g COD·L -1 ·d -1 and the hydraulic retention time from 8.8 h to 24 h.Distribution of organic acids,the contents of propionic and butyric acids in the effluent in particular were also dependent on the COD loading rate.The thermophilic UASB reactor showed a stable performance on hydrolysis and acidogenesis of starch as well as suspended solid removal at short hydraulic retention times and high influent pH(10～11),during the operation of 110 d.

STUDY AND SIMULATION OF AN ACTIVATED SLUDGE TREATMENT FOR METHYL VIOLET WASTE WATER

This paper researched a promising biological treatment of methyl violet waste water by methods of activated sludge.Effects of temperature and pH were studied on this process.Kinetic equation of the substrate biodegradation was investigated in the experimental range.It was studied and simulated that flow within the bubble region of this bioreactor according to the κ ε two fluid equation.Simulation results agree well with experimental data.

Enhanced Biological Phosphorus Removal with Pseudomonas putida GM6 from Activated Sludge

The enhanced biological phosphorus removal （EBPR） method is widely adopted for phosphorus removal from wastewater, yet little is known about its microbiological and molecular mechanisms. Therefore, it is difficult to predict and control the deterioration of the EBPR process in a large-scale municipal sewage treatment plant. This study used a novel strain isolated in the laboratory, Pseudomonas putida GM6, which had a high phosphate accumulating ability and could recover rapidly from the deteriorated system and enhance the capability of phosphorus removal in activated sludge. Strain GM6 marked with gfp gene, which was called GMTR, was delivered into a bench-scale sequencing batch reactor （SBR） of low efficiency, to investigate the colonization of GMTR and removal of phosphorus. After 21 days, the proportion of GMTR in the total bacteria of the sludge reached 9.2%, whereas the phosphorus removal rate was 96%, with an effluent concentration of about 0.2 mg L^-1. In the reactor with the addition of GMTR, phosphorus was removed quickly, in 1 h under anaerobic conditions, and in 2 h under aerobic conditions. These evidences were characteristic of EBPR processes. Field testing was conducted at a hospital sewage treatment facility with low phosphorus removal capability. Twentyone days after Pseudomonas putida GM6 was added, effluent phosphorus concentration remained around 0.3 mg L^-1, corresponding to a removal rate of 96.8%. It was therefore demonstrated that Pseudomonas putida GM6 could be used for a quick startup and enhancement of wastewater biological phosphorus removal, which provided a scientific basis for potential large-scale engineering application.

Cascade sulfidation and separation of copper and arsenic from acidic wastewater via gas-liquid reaction

Copper and arsenic in acidic wastewater were separated by cascade sulfidation followed by replacement of arsenic in theprecipitates by copper in the solution which was realized by recycling precipitates obtained in the first stage into the initial solution.The effects of reaction time,temperature and H2S dosage on copper and arsenic removal efficiencies as well as the effects of solid-toliquidratio,time and temperature on the replacement of arsenic by copper were investigated.With20mmol/L H2S at50°C within0.5min,more than80%copper and nearly20%arsenic were precipitated.The separation efficiencies of copper and arsenic werehigher than99%by the replacement reaction between arsenic and copper ions when solid-to-liquid ratio was more than10%at20°Cwithin10min.CuS was the main phases in precipitate in which copper content was63.38%in mass fraction.

Extractable Fractions of Metals in Sewage Sludges from Five Typical Urban Wastewater Treatment Plants of China

Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR （Community Bureau of Reference） sequential extraction procedure. The sludges contained considerable amounts of organic matter （31.8%- 48.0%）, total N （16.3-26.4 g kg^-1） and total P （15.1-23.9 g kg^-1）, indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China＇s control standards for pollutants in sludges from agricultural use （GB 4284-1984）. The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.

Research on mechanism of groundwater pollution from mine water in abandoned mines

In order to understand the mechanism and regularity of the groundwater contamination from mine water of abandoned mines, experiments were conducted on an abandoned coal mine in Fuxin, a representative city with lots of mine water in northeast China. The groundwater pollution from different contaminants of coal-mining voids （total hardness, SO4^2-, CI^- and total Fe） and pollution factors transportation situation in the coal rock were simulated by soil column experiment under the conditions of mine water leaching and main water leaching （similar to rainwater leaching）, and the water-rock interaction mechanism was discussed during mine water infiltration through saturated coal rock by application of principle of mass conservation, based on physical properties of coal rock, as well as monitored chemical composition. The results show that, compared with the clear water leaching process, trends of change in pollutant concentrations presented different characteristics in the mine water leaching process. Groundwater is contaminated by the water rock interactions such as migration ＆ accumulation, adsorption ＆ transformation, dissolution ＆ desorption and ion exchange during the mine water permeation. The experiments also suggest that at first dissolution rate of some kinds of dissoluble salts is high, but it decreases with leaching time, even to zero during both the mine water leaching and main water leaching.

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.

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.

Principal Component Analysis of Major Pollutants Discharge Amount in Major Cities

With the development of industry in China, the emission issues of indus- trial wastewater has got more and more attention. Excessive levels of pollutants in wastewater are urgent problem to be solved. Together with the emissions of do- mestic wastewater, the discharge amount of pollutants has exceeded standard in many cities, which not only pollutes the water resources, but also greatly threatens the environment, and does great harm to people＇s health. The principal component analysis was conducted based on the principal components extracted from the data of major pollutants emission conditions in the wastewater of major cities from the China Statistical Yearbook 2014.

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.

Composition and distribution of main pollution trace element in water environment of mining subsidence

The impact on these water bodies of the surrounding coal production activities and the power plant through research the content and characteristics of harmful trace elements in coal contained in these water bodies.F,Hg,Se and As these four trace ele- ments increased 0.92%,0.78%,0.70% and 0.81% respectively in Datong mining subsi- dence pool from November 2004 to November 2006;the four elements increased 1.58%, 1.23%,1.08% and 0.92% respectively in Xie'er mining subsidence pool;the four ele- ments increased 1.16%,1.06%,1.02% and 1.01% respectively in Pansan mining sub- sidence pool.The conclusions show that the absolute values of F,Hg,Se and As in mining subsidence pool are relate with their background value,while the increase in their concen- tration and their environment of mine and electricity plant surrounded are closely linked.

A New Method for Effluent Treatment System Design

this paper mainly discusses the design of distributed effluenttreatment systems with single contami- nant. A new method is putforward and four basic rules are provided. The key point of themethod is that global optimality is obtained by guaranteeing theoptimality of each step taken in the design. Costs per unit mass ofremoved contaminant are used as a scale to choose the nextcombination of an effluent stream and a treatment process. Theremaining problem is updated after each choice. As for multiplecontaminants, a two-stage method is adopted.

State Space Approach to Mass Exchange Network Synthesis

State space approach is an effective method to mass-exchange network (MEN) synthesis. By decomposing the network into two interactive parts, a distribution network and a process operator, the synthesis problem can be formulated into a mixed integer nonlinear programming (MINLP) model. In this article, a generalized state space model based on typical MEN is established and verified in two cases. A new asymmetrical operator and cost index are also adopted to speed up the solution process. The results demonstrate the efficiency of the proposed approach.

Acidophilic bacterial community reflecting pollution level of sulphide mine impacted by acid mine drainage

To reveal the impact of mining on bacterial ecology around mining area,bacterial community and geochemical characteristics about Dabaoshan Mine(Guangdong Province,China)were studied.By amplified ribosomal DNA restriction analysis and phylogenetic analysis,it is found that mining pollution greatly impacts the bacterial ecology and makes the habitat type of polluted environments close to acid mine drainage(AMD)ecology.The polluted environment is acidified so greatly that neutrophil and alkaliphilic microbes are massively dead and decomposed.It provided organic matters that can make Acidiphilium sp.rapidly grow and become the most bacterial species in this niche.Furthermore,Acidithiobacillus ferrooxidans and Leptospirillum sp.are also present in this niche.The amount of Leptospirillum sp.is far more than that of Acidithiobacillus ferrooxidans,which indicates that the concentration of toxic ions is very high.The conclusions of biogeochemical analysis and microbiological monitor are identical. Moreover,because the growth of Acidithiobacillus ferrooxidans and Leptospirillum sp.depends on ferrous iron or inorganic redox sulfur compounds which can be supplied by continual AMD,their presence indicates that AMD still flows into the site.And the area is closer to the outfalls of AMD,their biomasses would be more.So the distinction of their biomasses among different areas can help us to find the effluent route of AMD.

Bioflocculant Produced by Klebsiella sp. MYC and Its Appli-cation in the Treatment of Oil-field Produced Water

Seventy-nine strains of bioflocculant-producing bacteria were isolated from 3 activated sludge samples. Among them, strain MYC was found to have the highest and stable flocculating rate for both kaolin clay suspension and oil-field produced water. The bacterial strain was identified as Klebsiella sp. MYC according to its morphological and biochemical characteristics and 16SrDNA sequence. The optimal medium for bioflocculant production by this bacterial strain was composed of cane sugar 20 g L^-1, KH2PO4 2 g L^-1, K2HPO4 5 g L^- 1, （ NH4）2SO4 0.2 g L^-1, urea 0.5 g L^- 1 and yeast extract 0.5 g L^- 1, the initial pH being 5.5. When the suspension of kaolin clay was treated with0.5% of Klebsiella sp. MYC culture broth, the flocculating rate reached more than 90.0% in the presence of 500mg L^-1 CaCI2, while the flocculating rate for oil-field produced water was near 80.0% in a pH range of 7.0 - 9.0 with the separation of oil and suspended particles from the oil-field produced water under similar conditions. The environment-friendly nature of the bioflocculant and high flocculating rate of the strain make the bioflocculant produced by Klebsiella sp. MYC an attractive bioflocculant in oil-field produced water treatment.

Technical Innovation of Land Treatment Systems for Municipal Wastewater in Northeast China

On the basis of ecological principles including holistic optimization, cycling and regeneration, and regional differentiation, land treatment systems (LTSs) for municipal wastewater were continuously explored and updated in the western Shenyang area and the Huolinhe area, China. Intensified pretreatment, addition of a man-made soil filtration layer, and use of an ecologically diversified secondary plant cover were proved to be technically feasible. Hydraulic loading was determined according to the assimilation capacity of soil ecosystems, thus ensuring safe operation of wastewater treatment. This modernized and alternative approach to wastewater treatment had been widely applied in middle-sized and small cities and towns of Northeast China, and these innovative systems in some areas had indicated favorable ecological, social, and economic benefits.