Kinetic regularities of ozone decomposition in water

The paper studied the impact of the pH and temperature on kinetics of ozone decomposition in water. It has been shown that in the pH range 4 to 8 it is well described by the equation of the second order reaction. At an increase of the pH and temperature the rate of ozone decomposition increases. The relationship between the logarithm of the constant and the pH at 19°C corresponds to the equation log k_(pH) = −0.7 + (0.49 ± 0.03)(pH 4). The energy of ozone decomposition activation constitutes 76.0 ± 8.3 kJ/mol. The presence in the solution of phosphate ions and tert-butyl alcohol substantially increases the rate of the decomposition chain process.     

曹妃甸净水工程净水厂设计工艺特点分析

介绍了曹妃甸工业区净水厂的概况及原出水水质和设计出水水质的要求,提出了具体的净水工艺流程,分析了净水工艺特点,得出了曹妃甸净水厂工程将会取得良好的社会效益和经济效益的结论。     

水源水质与净水厂改造适用工艺

我国饮用水水源受工业污染、农业污染、城市生活污染等多方面影响,水源水质严重恶化,有机物污染和臭味成为普遍关注的水质问题。针对我国水源水微污染水质,无论是作为把关技术去除溶解性大分子有机污染物与臭味,还是从经济适用观点出发,臭氧-生物炭技术目前仍然是经济有效的深度处理技术。     

奥利亚罗非鱼促性腺激素释放激素及相关肽基因的克隆与表达

采用RT-PCR方法从奥利亚罗非鱼丘脑中扩增出长约386 bp的目的序列GnRH/GAP,先将其克隆到T载体上,通过酶切鉴定、序列测定分析,确认序列的正确性后,将此片段克隆到表达载体pMAL-c2x中构建重组表达质粒pMAL-GnRH/GAP,再转化到大肠杆菌TB1中,经IPTG诱导后成功表达出与预期大小相符的相对分子量约56 000的融合蛋白。     

浅谈净水厂改造工程的项目管理

净水厂改造项目不仅拥有一般工程项目的工程管理过程及要求,还具有其自身的特点。其项目的管理在充分运用工程项目管理的知识、技能、手段和方法的基础上,还应抓住项目自身特点,结合现场实际情况,实施工程项目的组织和管理。本文结合工程案例介绍了净水厂改造项目的特点及其项目的管理。     

Effect of water purification on its radioactive content

We have analyzed the dissolved activity of various radionuclides of natural origin (226Ra and (234,235,235)U) and artificial origins (90Sr and (239+240)Pu), together with other non-radioactive physico-chemical parameters (pH, conductivity, dry residue, [Ca2+], [Mg2+], [K+] and [Fe(2+,3+)], in both pre-potable and potable water from 17 treatment plants in Extremadura (Spain). We have established a series of criteria and complementary techniques to the traditional methods of purification, aimed at the quantitative elimination of the presence in solution of the mentioned radionuclides. We highlight: (a) the increment of the mineral content of the water in its treatment succeeds in eliminating 226Ra, until reaching values close to 70%; (b) the increment of the mineralization of the water by addition of chemical reagents, conducted within the pH values 7.1 and 7.8, succeeds in eliminating up to 90% of the total uranium in dissolution; (c) the elimination of 90Sr during the purification is poor, in general, reaching average levels of only 15% when the purification process is practiced within concrete ranges for potable water (pH > 7, conductivity > 150 microS/cm, dry residue > 150 mg/l, [Ca2+] > 10 mg/l and [Mg2+] > 1.2 mg/l), and finally, (d) the decrease of the solubility of the iron, as low as it can get during the purification process, together with an increase of the conductivity associated, in principle, to parallel increments of other variables not analyzed in this work, such as SO4(2-), CO3(2-), etc., the activity of dissolved (239+240)Pu decreases to 90%. The application of the traditional processes of water purification outside the ranges and criteria formulated can increase the presence in dissolution up to 400%, for some radionuclides, largely the consequence of its redissolution from the non-soluble fraction of the water.     

人工湿地在湖水净化和中水回用中的应用

介绍了高效垂直流人工湿地处理系统在公园湖水水质净化和小区生活污水处理及回用中的应用,综合分析了系统运行后对污染物的去除效果.结果表明,人工湿地技术对富营养化水体的处理效果较好,其中对BOD5和TN的去除率高于55%,TP去除率为80%～90%,叶绿素a去除率高于63%,湿地出水水质达到了国家地表水标准中Ⅲ～Ⅳ类水体水质.该系统用于小区生活污水处理及回用时,运行稳定,出水水质可以满足绿化用水水质要求,且达到了良好的景观效果,具有良好的经济效益和应用前景.     

Photooxidation and subsequent biodegradability of recalcitrant tri-alkyl phosphates TCEP and TBP in water

Biodegradable organic carbon (BDOC) from OH radical oxidation (UV-H₂O₂) of the recalcitrant industrial anti-foaming agents and flame retardants, tri-n-butyl phosphate (TBP) and tris(2-chloroethyl) phosphate (TCEP), was quantified with respect to the fraction of the TBP or TCEP photooxidized. For 50-96% contaminant oxidation via OH, BDOC was similar in solutions of either compound, and ranged from 0.25 to 0.5 mg L⁻¹ (TBP₀ and TCEP₀ = 5 mg L⁻¹). In addition, for this contaminant oxidation range, complete dehalogenation of TCEP was observed, along with a significant change in pH. Oxidation of TCEP results in both H⁺ and Cl⁻ release, while the TBP mineralization pathway results in CO₂, H₂O, H⁺, and PO₄³⁻. For low μg/L levels of TCEP contamination in treated surface waters, UV-H₂O₂ oxidation of TCEP or TBP would not be expected to impact pH or chloride concentrations, however, a portion of the TCEP or TBP oxidation products, likely in non-halogenated aldehyde form, would become an available carbon source for bacterial growth in storage, distribution, or during further physical treatment.     

Electrocoagulation purification of water of Cr6+ compounds

The process of the electrocoagulation purification of water containing chromium, depending on pH, Cr⁶⁺ concentration, ions of metal impurities and ratios Fe²⁺ : Cr⁶⁺ have been investigated. We have found the upper boundary of chromium concentrations (150 mg/dm³) whereby its residual content in water does not exceed MAC for the discharge to the complex of facilities of water disposal. It has been shown that ions of metal impurities present in the water in electrocoagulation are removed together with chromium ions.     

生物活性炭对水的净化作用

世界各地已广泛采用粒状活性炭去除饮用水中的溶解有机物。在20世纪70年代发现细菌在粒状活性炭过滤器中滋生繁殖，可去除一些过滤器中的有机物。依据此项发现，预臭氧化被发现可以大大增强粒状活性炭的生物活性。臭氧化和粒状活性炭的组合使用一般被称为生物活性炭工艺，又称为生物增强型活性炭工艺。     

Silver-modified mesoporous TiO2 photocatalyst for water purification

Mesoporous anatase (TiO₂) was modified with silver (Ag) nanoparticles using a photoreduction method. Performance of the resulting TiO₂-Ag nanocomposites for water purification was evaluated using degradation of Rhodamine B (RhB) and disinfection of Escherichia coli (E. coli) under ultraviolet (UV) irradiation. The composites with different Ag loadings were characterized using physical adsorption of nitrogen, X-ray diffraction, X-ray photoelectron spectroscopy and UV-Visible diffuse reflectance spectroscopic techniques. The results showed that metallic Ag nanoparticles were firmly immobilized on the TiO₂ surface, which improved electron-hole separation by forming the Schottky barrier at the TiO₂-Ag interface. Photocatalytic degradation of RhB and inactivation of E. coli effectively occurred in an analogical trend. The deposited Ag slightly decreased adsorption of target pollutants, but greatly increased adsorption of molecular oxygen with the latter enhancing production of reactive oxygen species (ROSs) with concomitant increase in contaminant photodegradation. The optimal Ag loadings for RhB degradation and E. coli disinfection were 0.25 wt% and 2.0 wt%, respectively. The composite photocatalysts were stable and could be used repeatedly under UV irradiation.     

万泉河引水工程净水工艺方案选择

介绍了万泉河引水工程概况 ,根据源水特点 ,对两种方案工艺流程作了比较 ,选择方案二作为净水工艺流程较为理想 ,指出该工程的建成 ,具有良好的经济效益、社会效益和环境效益。     

Combined ultrafiltration-adsorption water purification of the cationic violet dye

The article investigated the impact of the VMK-1 activated carbon, produced from apricot stones in their pyrolysis in the flow of water steam, on the transmembrane stream and the retention of capacity of the UPM-50 ultrafiltration membrane with respect to the cationic violet dye. It has been shown that the combination of adsorption and ultrafiltration with the process in one unit makes it possible to substantially raise the degree of water purification of the dye concurrently with an increase of the process capacity of purification and prolongation of the membrane service life.     

Ultrafiltration purification of underground water during its various preconditioning

We have carried out a comparative verification of functional characteristics of polysulfone membranes with the rated molecular-mass maximum 50 kamu in ultrafiltration treatment of underground water containing iron with various preconditioning. It has been shown that in studied conditions the treatment process proceeds against the background of reducing the membrane capacity due to the formation of a deposit of iron hydroxide in the pores and on the surface. It has been established that intensity of decreasing the capacity of membranes and the degree of recovering their initial capacity depend on water preconditioning, which acts as a factor determining these processes. Based on the research results we proposed hypotheses of the mechanisms of sedimentation for studied conditions of ultrafiltration treatment of underground water containing iron.     

Continuous radial filtration in the purification of oily water

A new type of continuous sand filter with cross flow of sand (downward flow) and of oily water to be filtered (radial flow) has been tried in order to achieve high separation efficiencies with rather high continuous rates of oily water. Many experimental runs have been carried out with different types and rates of sand and with different water rates and inlet concentration. The results seem to demonstrate that continuous radial filtration offers an encouraging means for the treatment of oil-polluted water.     

论翻转课堂在高校法学本科教学中的应用

在高校法学本科教育中有必要引进翻转课堂的教学理念与教学模式。高校应充分发挥翻转课堂形式的优势,着重解决法学本科教学理论与实践脱节的问题,建立以法学基础课程为范围的翻转课堂应用体系。翻转课堂在高校法学本科教学中的实施尤其要特别关注配套学习方法的革新、视频资料制作与法学教材编写以及针对翻转课堂的教学评价标准的确立等问题,真正使翻转课堂在法学本科教学活动中发挥出应有的重要作用。     

住宅采暖分户热计量系统型式的探讨

阐述了单管水平串联系统是分户热计量较合适的型式,并对系统的工程设计进行了分析,指出对于分户热计量这一新课题,在工程设计中,建筑、结构应给予充分配合。     

超滤膜技术在净水工艺中的应用

从超滤膜技术的分离原理、超滤膜组件以及超滤膜的优势等方面对第三代饮用水处理工艺——超滤膜工艺进行了较为全面的分析,并介绍了超滤膜在国内外的发展情况,指出了超滤膜技术的发展前景。     

Anaerobic purification of waste water from a potato-starch producing factory

The waste water of the potato-starch factory of the AVEBE in De Krim (The Netherlands) passed, during the anaerobic purification, a sedimentation pond, a first upflow reactor (in which there was practically no sludge retention) and a UASB methane reactor. The fermentation of free-amino acids and smaller peptides occurred in the sedimentation pond and first reactor. Proteins and longer peptides were degraded in the first reactor and in the methane reactor. The decrease in COD and TOC content of the waste water between influent sedimentation pond and effluent methane reactor was 83 and 71%, respectively. In the effluent of the first reactor, 60% of the inorganic sulfur was present as sulfide.     

西曲矿井下污水处理改造

全面阐述了西曲矿井下污水治理的现状和存在问题,分析了矿井污水污染的特点和BH净水工艺的处理效果通过深入现场和现场实验,得出了可行性结论,提出了改进方案,对其它煤矿矿井污水处理具有深远的意义。