循环冷却水系统最小排污水量的计算

本文论述了循环冷却水系统的排污水量是由浓缩倍数来决定的，而控制浓缩倍数是从控制结ＣａＣＯ３ 垢，ＣａＳＯ４ 垢，ＭｇＳｉｏ３ 垢及ＰＨ

数据中心开式循环冷却水系统缓蚀阻垢实践

水垢和腐蚀问题是影响数据中心开式循环冷却水系统正常运行的两个主要因素,目前,业内主要采用定期添加缓蚀阻垢药剂和及时排污的方法进行治理。笔者通过调研发现,大部分数据中心企业并未对药剂用量及排污水量大小进行科学规划,导致冷却水系统水质无法得到准确控制,由此形成的水垢或腐蚀杂质导致暖通设备运行功耗高、隐患大,威胁数据中心运营安全。因此,如何精确控制开式循环冷却水系统水质是当前数据中心暖通系统安全且高效运行的重点和难点。本文以华东某数据中心水处理为实例,对如何科学治理开式循环水系统缓蚀阻垢过程进行介绍分析。

循环冷却水的浓缩倍数

综述了浓缩倍数的测定方法及其与补充水量M、排污水量B、蒸发水量E等运行参数和节水量的关系,说明合理控制浓缩倍数的重要性.

宝钢焦化厂清循环系统水质稳定调查

焦化厂冷却水循环用量为27万m^3/d,应用S-205、T-225、A-411、A-491等药剂一年多来平均补水量0.94万m^3/d,循环率为96.5%,平均腐蚀速度为3.55m·d·d,污垢附着速度为3.15m·c·m.循环率和防腐阻垢效果都达到设计要求,赶上国际水平.如能均匀投药,则效果更好.总结出规律后可按不同季节逐步减少用药量.目前已有国产仿制药剂,试用后可节省外汇1.4亿日元/年.

提高和稳定冷却水浓缩倍数的意义

叙述循环冷却水系统浓缩倍数的概念，列出了浓缩倍数与补充水量、排污水量及蒸发水量的关系式，论证了提高和稳定冷却浓缩倍数的意义。认为适当提高循环冷却水的倍数，可以降低系统的补充水量和排污水量。

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.

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.

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.

Factor Analysis on Quantity of Discharged Pollutants in Wastewater in Major Cities

The research performed statistical analysis on 186 data concerning the amount of discharged industrial wastewater, the amount of oxygen demand of industrial wastewater, the amount of ammonia and nitrogen discharged from industries, the amount of urban discharged domestic sewage, the amount of daily life chemical oxygen demand, and the amount of domestic ammonia and nitrogen to explore source of pollutants from wastewater and guarantee urban water quality.Factor analysis was then performed with SPSS according to discharge quantity of pollutants. The results should that the major pollutants are from domestic sewage it is expected scientific suggestions be proposed on water quality in our country.

Factors Impacting Water Quality of a Small Stream in a Mountain Forest

Recent improvements to sewerage systems have meant that the relative contribution of point sources of pollution to the overall pollutant loads of streams has decreased markedly. Consequently, the potential increase in non-point source pollution means that it may be necessary to focus more on pollution loads from non-point sources in the future. This study examined pollution loads from non-point sources in streams flowing through forested areas. In addition, the relationship between runoff and pollution loads was also clarified. The small streams in the Tohoku University Botanical Gardens, in Sendai city, Japan, were sampled during a dry weather period and their water quality parameters were characterized. Chemical Oxygen Demand （COD） concentration increased with distance downstream, possibly because the soils in downstream areas contained high amounts of organic matter. Conversely, the concentration of nitrate nitrogen （NO3-N） decreased with distance downstream, probably because upstream soils were generally in an oxidized state while those further downstream were reduced. COD concentration increased with air temperature, while NO3-N levels decreased with an increase in air temperatures.

Experimental Research on Coke Wastewater Treatment by Hybrid Biological Reactor

Phase hybrid biological reactor （HBR） was used in treating coke wastewater by adding submerging fiber-ball fillers in suspended growth activated sludge. The optimum operation parameters for the highest performance were determined. It was found that the hybrid biological reactor worked well for the coke wastewater treatment in terms of Chemical Oxygen Demand （COD）, NH4＋ -N and other refractory organic compounds removal efficiencies. Compared with conventional activated sludge system, the removal rate of COD and NH4＋ -N and the nitrating rate were higher and more stable in the hybrid biological reactor. COD of effluent was less than 75 mg/L and the removal rate of COD and NH4＋ -N could be up to 95.0% and 92.5% when COD of influent and NH4＋ -N were less than 700 mg/L and 300 rag/L, respectively. In this way, the quality of effluent concentration could reach the first class of integrated wastewater discharge standard （GB8978-1996） （COD ≤100 mg/L）.

Effects and driving factors of domestic sewage from different sources on nitrous oxide emissions in a bog

Direct sewage discharge may enhance soil nitrous oxide(N_(2)O)emissions,worsening the greenhouse effect.However,the effects of sewage discharge into bogs on N_(2)O flux,drivers and influencing mechanisms remain unclear.Additionally,investigating the impact of reclaimed water on N_(2)O flux is important for bog replenishment and water shortage alleviation.This study simulated sewage from different sources into a bog and analyzed N_(2)O fluxes,soil(organic carbon,total nitrogen,ammonium nitrogen,nitrate nitrogen,total phosphorus,available phosphorus,pH and electrical conductivity),plant(species richness and biomass)and microorganisms(ammonia-oxidizing archaea,napA,nirS,nirK and nosZ genes).Results showed that the reclaimed water did not significantly change N_(2)O flux,while 50%tap water mixed with 50%domestic sewage and domestic sewage significantly increased the N_(2)O flux.Among soil factors,available nitrogen and pH were key in influencing N_(2)O flux.Among plant parameters,species richness was the primary factor affecting N_(2)O flux.Nitrogen transformation functional genes contributed the most to the increase in the N_(2)O fluxes,with an increase in domestic sewage input leading to a higher abundance of these genes and subsequent N_(2)O emissions.Therefore,domestic sewage should be considered,as it significantly increases N_(2)O emissions by affecting the soil,plants and microorganisms,thereby increasing the global warming potential.This study’s findings suggest that using treated reclaimed water for bog replenishment could be an environmentally friendly approach to wetland management.

Potentials of GHG reductions from wastewater treatment for the CDM

The study aims to evaluate the potential of GHG （greenhouse gas） reductions by installing an anaerobic digester in a wastewater treatment facility in Southeast Asia. Then the break-even point of additional investment to reduce GHG is obtained by exchanging carbon price as emissions credits. In the project scenario, the wastewater treatment system has the digester, where methane （biogas） is produced and recovered. Compared with the baseline scenario, the biogas has calorific value to produce heat and electricity, and can substitute fossil fuels for power generation. The objective of the study is to define the relationship between CERs （certified emission reductions） and investment costs, and the beak-even point, finding out the dominant pa- rameters in the system. Financial parameters such as capital costs and operating costs are considered to evaluate the investmerit costs. The result shows that the methane recovery reduces 54% of GHG emissions. Although the substitution of the biogas for the fossil fuels reduces only 6% of the GHG emissions, the electricity output can satisfy the electricity consumption. The results also show that the maximum CER credit is 73000 t-COEe/a, and the GHG reduction cost is 14 USD/t-CO2e.