城市景观水污染现状及处理技术

城市景观水体由于水质恶化而渐渐影响附近居民的正常生活,要从根本上保证水质需采取一定的水源保护和水处理措施。在景观水处理中,适用于景观水处理的工艺有很多,但工程实施中需要对其进行选择、优化、组合。随着社会不断发展和人们生活质量要求不断提高,景观水处理也必将成为继生活用水处理、工业用水处理后的又一给水处理新领域。     

Growth factors, kinetics and biodegradation mechanism associated with Pseudomonas nitroreducens TX1 grown on octylphenol polyethoxylates

The growth properties and biodegradation mechanism of a Gram-negative bacterium, Pseudomonas nitroreducens TX1 that was able to grow on branched octylphenol polyethoxylates (OPEO(n), average n=9.5) as the sole carbon source over a wide concentration range (1-100,000 mgl(-1)) were studied. Analysis of growth factors indicated the highest specific growth rate (micro) of 0.53 h(-1) was obtained at an initial concentration of 5,000 mgl(-1) OPEO(n). An optimal C/N ratio of 12 was obtained for (NH(4))(2)SO(4) as the nitrogen source in a cultivated medium at pH 7. The kinetic analysis demonstrated that bacterial growth and OPEO(n) degradation followed the Monod equation and were based on a substrate concentration inhibition model and pseudo-first-order reaction, respectively. The substrate inhibition coefficient was over 18,000 mgl(-1) and this indicates that the strain has an ability to sustain growth at high concentrations of OPEO(n) and use it as the sole carbon source under such a stress condition. Furthermore, LC-MS analysis showed that the biodegradation mechanism of dodecyl octaethoxylate (AEO8) by P. nitroreducens TX1 was the sequential cleavage of the ethoxylate chain.     

喷淋环栅式除尘脱硫反应器的数学模拟

研制了一种由内外圈构成的喷淋环栅式除尘脱硫反应装置,气、液两相在内外圈之间通向运动,紊流冲激环栅时接触传质。基于溶质渗透理论,提出了以内塔穿孔速率V,液气比L/G,吸收浆液pH值为参数的脱硫效率模型。对比某电厂工况条件下测得的一系列实验数据,显示出该模型与实际情况具有良好的一致性,表明该模型可以用来作为工程设计、最优化技术和推测工业数据的理论参考工具。     

电催化同步降解水中硝酸盐氮和有机氯化物的研究

在利用电化学反应器单独脱硝脱卤的电催化实验基础上,对电化学催化方法同步脱硝脱卤进行研究.试验采用化学沉积法负载钯-铜合金(4∶ 1)的多孔钛板作为电解反应器阴极,电解硝酸盐氮(NO-3-N)和五氯酚(PCP)的混合溶液.结果表明: PCP的脱卤效果与单独脱卤时相似,但PCP的存在对NO-3-N的还原脱除有明显影响.PCP在钯原子上的竞争性吸附抑制了NO-3-N还原反应的中间产物NO-2-N继续还原,导致在反应初期出现NO-2-N的积累;随着PCP的充分还原,前期积累的副产物NO-2-N可以逐渐被降解.分批试验和推流试验结果表明,利用多孔钛板负载的钯-铜二元合金电极,选择合适的反应参数,可有效地脱除水中的硝酸盐氮和卤代有机物.     

城市危险化学品事故统计分析与对策

通过对2002-2004年发生在中国内地12个主要城市的435起非爆炸品类危险化学品事故统计分析,发现:(1)危险化学品事故总体呈进一步发展趋势;(2)处于城市生活区的化工企业发生危险化学品事故对城市的影响最大;(3)危险化学品在运输阶段,发生事故的比例最高;(4)民用燃气是造成使用阶段危险化学品事故的主要危险源,而人为失误和违规操作是民用燃气类危险化学品事故的主要原因.在统计分析基础上提出了相应的对策.     

层状氢氧化镁铝对偶氮染料酸性黑10B的脱色性能研究

分别用层状氢氧化镁铝(LDH)和焙烧层状氢氧化镁铝(CLDH)作为吸附剂吸附脱除水溶液中偶氮染料酸性黑10B.考察了脱色时间、pH值、吸附剂的投加量、温度、染料初始浓度和焙烧温度等因素对脱色率的影响.结果表明,LDH及CLDH对酸性黑10B染料具有良好的脱除效果,室温下,10g/L LDH和1g/L的CLDH对浓度为100mg/L的染料的脱色率分别达95.93%和99.97%.pH值是影响吸附能力的关键因素,吸附剂对溶液pH值有一定缓冲作用.LDH及CLDH对酸性黑10B吸附结果符合Langmuir吸附等温式.饱和吸附后的LDH及CLDH用高温热解法再生,吸附性能良好,随再生次数增多,脱色率下降.     

高浊度污水快速净化新技术

介绍了一种快速净化高浊度污水的新技术,该技术根据化学强化一级处理(chemically enhanced primary treatment,CEPT)技术、闪速混合(flash mixing)技术、旋流和点涡流絮凝技术、悬浮泥层过滤技术和过滤水力学原理等理论,采用物理化学法去除污水中的有机污染物和其他有害杂质,其有着流程简单可靠、投资和运行费用低、占地少、净化效果好的优势.     

碳责任账户的目标原则、分配逻辑与框架构建：账户建立

随着全球环境问题日趋严重,企业和消费者日益认识到减缓气候变化的紧迫性。作为经济活动的主要参与者,减少温室气体排放已经成为任何单个企业及其供应链的巨大挑战。供应链的所有参与者都需要为气候减缓做出努力。现有的碳排放责任核算大多从企业的生产方面入手。最终消费者作为供应链的重要参与者,是所有生产者的最终服务对象,同样具有不可忽视的碳减排作用以及应承担的碳减排责任。本文提出以产品为导向,考虑产品生产过程中的直接碳排放和间接碳排放,建立产品碳排放基准值,对基于供应链的所有参与主体进行责任分配,进而建立基于供应链的碳责任账户。本文构建的责任体系框架具有更广泛、更有前景的应用潜力。     

焦化场地典型多环芳烃类污染物精细化风险评估

为准确评估多环芳烃(PAHs)污染土壤对人体的健康风险,解决目前基于总量风险评估导致土壤PAHs修复目标值过严的问题,采用德国标准研究院颁布的生物可给性测试方式研究了石家庄某焦化厂土壤中苯并[b]荧蒽(BBF)、苯并[k]荧蒽(BKF)、苯并[a]芘(BAP)、茚并[1,2,3-cd]芘(IPY)和二苯并[a,h]蒽(...     

Field released transgenic papaya effect on soil microbial communities and enzyme activities

Soil properties, microbial communities and enzyme activities were studied in soil amended with replicase （RP）-transgenic or non-transgenic papaya under field conditions. Compared with non-transgenic papaya, significant differences （P〈0.05） were observed in total nitrogen in soils grown with transgenic papaya. There were also significant differences （P〈0.05） in the total number of colony forming units （CFUs） of bacteria, actinomycetes and fungi between soils amended with RP-transgenic plants and non-transgenic plants. Compared with non-transgenic papaya, the total CFUs of bacteria, actinomycetes and fungi in soil with transgenic papaya increased by 0.43-1.1, 0.21-0.80 and 0.46-0.73 times respectively. Significantly higher （P〈0.05） CFUs of bacteria, actinomycetes and fungi resistant to kanamycin （Km） were obtained in soils with RP-transgenic papaya than those with non-transgenic papaya in all concentrations of Km. Higher resistance quotients for Km＇ （kanamycin resistant） bacteria, actinomycetes and fungi were found in soil planted with RP-transgenic papaya, and the resistance quotients for Km＇ bacteria, actinomycetes and fungi in soils with transgenic papaya increased 1.6-4.46, 0.63-2.5 and 0.75-2.30 times. RP-transgenic papaya and non-transgenic papaya produced significantly different enzyme activities in arylsulfatase （5.4-5.9x）, polyphenol oxidase （0.7-1.4x）, invertase （0.5-0.79x）, cellulase （0.23-0.35x） and phosphodiesterase （0.16-0.2x）. The former three soil enzymes appeared to be more sensitive to the transgenic papaya than the others, and could be useful parameters in assessing the effects of transgenic papaya. Transgenic papaya could alter soil chemical properties, enzyme activities and microbial communities.