烟台夹河河口海水混合过程的地球化学特征研究

海(咸)水混入是河口河水重要的地质过程,深刻地影响河水地球化学过程。本文系统采集夹河河口水样,分析海淡水混合过程的地球化学特征。结果表明,远离河口段(J10~J14)为淡水性质,主要受水-岩作用及人类活动等影响;近河口段(J1~J8)海水混入严重,F~-、Cl~-、Br~-、SO~(2-)_4、Na~+、K~+、Mg~(2+)、Ca~(2+)、盐度等明显较高,主要受海水混入影响。近河口段存在Na-Ca离子交换过程,约占Na~+总量的0.9%~1.5%,离子交换量随海水混入比例增加而增加,Na~+离子交换量与K~+,Ca~(2+)、Mg~(2+)、Br~-、F~-、SO~(2-)_4离子交换量相关,且河水离子含量与盐度回归系数略低于与盐度、Na~+交换量回归系数,表明河口段河水离子交换影响河水地球化学特征。     

反渗透工艺在冷轧废水脱盐处理的应用

利用反渗透工艺对冷轧废水生化处理废水进行处理,获得了较好的脱盐效果。选取进水含盐量、回收率、pH值对系统脱盐率的影响。结果表明:当进水电导率为1 360μs/cm时,系统脱盐率可达94.7%;进水电导率为3 353μs/cm时,系统脱盐率为85.9%。当系统回收率低于77%时,除盐率受其影响较小在90%左右,但是若进一步增加系统回收率,则脱盐效果显著下降。当进水pH值越高脱盐效果越高,但为降低结垢风险,本系统进水pH值控制在7.1左右。     

盐度变化对崇明东部河口潮滩氮营养盐循环影响实验模拟研究

以长江口咸淡水交互作用最为典型岸段崇明东部潮滩作为研究区域,运用实验模拟方法,定量地研究了盐度变化对潮滩生态系中无机氮的迁移、转化过程的影响。结果发现,盐度升高有利于沉积物中的NH4-N向上覆水扩散,但NO2-N和NO3-N的界面扩散呈现相反的变化趋势;沉积物中可交换态无机氮含量变化特征显示,在盐度变化剧烈的潮滩生态系统内,硝化作用可能是控制沉积物(尤其是表层沉积物)中无机氮分布的重要因素。     

Effects of seawater salinity on nitrite accumulation in short-range nitrification to nitrite as end product

The effect of seawater salinity on nitrite accumulation in short-range nitrification to nitrite as the end product was studied by using a SBR. Experimental results indicated that the growth of nitrobacteria was inhibited and very high levels of nitrite accumulation at different salinities were achieved under the conditions of 25--28℃, pH 7.5--8.0, and the influent ammonia nitrogen of 40--70mg/L when seawater flow used to flush toilet was less than 35% (salinity 12393 mg/L, Cl^- 6778mg/L) of total domestic wastewater flow, which is mainly ascribed to much high chlorine concentration of seawater. Results showed that high seawater salinity is available for short-range nitrification to nitrite as the end product. When the seawater flow used to flush toilet accounting for above 70% of the total domestic wastewater flow, the removal efficiency of ammonia was still above 80% despite the removal of organics declined obviously(less than 60% ). It was found that the effect of seawater salinity on the removal of organics was negative rather than positive one as shown for ammonia removal.     

火电厂海水淡化工艺的技术经济分析及选择

简述了膜法与低温多效蒸馏法海水淡化原理,对低温多效和多套反渗透海水淡化装置进行了技术经济比较分析,比较分析了其制水综合成本和运行成本。比较结果表明,低温多效法高于反渗透法,反渗透法海水淡化加一级反渗透与低温多效法相当。并且,对八角电厂2种待选海水淡化方案做了经济技术比较,最终确定了八角电厂的海水淡化方案。     

天津沿岸海水中创伤弧菌的PCR检测和定量

采用普通PCR方法和SYBR Green实时定量PCR方法,根据创伤弧菌16S rDNA和23S rDNA基因间隔序列(internal transcribed spacer,ITS)设计引物,对渤海湾天津沿岸海水中的创伤弧菌进行了定性和定量检测.8个样品采集自天津市汉沽区沿岸海水,采集时间分别为2008年7月、10月和2009年3月、5月.PCR检测结果表明,这些样品都能扩增出276 bp的ITS序列,这些序列和GenBank上的同源序列(DQ462478)的相似性为96%～98%.用SYBR Green实时定量PCR方法测定了8个海水样品,样品中创伤弧菌的浓度为7.12×10~3～8.40×10~5 个/L,表明天津沿岸海水存在严重的创伤弧菌污染.     

工程规模长填龄渗滤液膜生物-纳滤组合设施各单元污染物去除效能

填埋场渗滤液性质复杂,普遍采用生物处理与深度处理多单元串联工艺;但是,因缺乏对工程运行规模中各单元污染物处理贡献的评估数据,使优化单元组合方式缺少理论依据.因此,本文采用常规和荧光光谱指标结合的方法,对以采用"膜生物反应器（membrane biological reactor,MBR）+纳滤（nanofiltration,NF）"工艺、处理能力800 m³·d^-1的工程设施为对象,分析该组合工艺各单元对长填龄渗滤液处理贡献;同时,利用三维荧光-平行因子分析方法（excitation emission matrix fluorescence spectroscopy-parallel factor,EEM-PARAFAC）评估渗滤液中溶解性有机物（dissolved organic matters,DOM）性质的变化.结果表明,生物处理阶段对溶解性氮（dissolved nitrogen,DN）去除贡献率为74.7%,其中一级反硝化单元对DN去除贡献率为54.6%,外置式超滤单元对溶解性化学需氧量（dissolved chemical oxygen demand,sCOD）和溶解性碳（dissolved oganic carbon,DOC）降低贡献率分别为92.2%和93.3%,纳滤单元可有效去除重金属和盐分,但能力有限.通过追踪长填龄渗滤液DOM变化发现,一级反硝化单元可去除长填龄渗滤液中75.4%的类蛋白物质,超滤单元主要截留亲水性较高的DOM,而高芳香性的腐殖质主要通过纳滤截留,腐殖化程度越高截留效果越好.研究结果提示,处理长填龄渗滤液时,MBR工艺生物处理单元可适当简化,超滤单元则应预防堵塞.     

盐度对厌氧氨氧化工艺处理含海水污水脱氮特性的影响

采用ASBR厌氧氨氧化反应器,通过逐步提高所含海水比例,研究了厌氧氨氧化工艺处理含海水污水的脱氮特性.结果表明:经过一定时间的驯化后,厌氧氨氧化菌可以在各个海水比例下保持活性并维持较高的脱氮性能.当海水比例不高于40%时,反应器的稳定性和脱氮效能几乎不受盐度提升的影响,同时厌氧氨氧化菌的活性还会得到增强,比厌氧氨氧化活性(SAA)最高时的海水比例为30%,是10%海水比例时的121.3%;当海水比例高于40%时,反应器的脱氮效能开始下降,但经过一段时间的驯化后会得到恢复,在此期间反应器对海水盐度的响应可分为敏感期、过渡稳定期和恢复期3个阶段.在100%海水比例下,反应器的NRR可达0.341kgN/(m³·d),为10%海水比例时的73.7%,且其还有进一步提升的趋势.     

水合物法海水淡化脱盐效率研究

采用水合物生成装置分别加入二氧化碳和甲烷气体通过水合物法进行2组海水淡化实验。每组实验分别提取3次不同反应时间的水合物晶体,检测水合物中Na+、Mg2+、K+、Ca2+、B3+的离子浓度。结果表明:CH4水合物形成过程中,盐离子的脱盐效率与离子半径和所带电荷量呈线性相关性。CO2水合物生成实验中,由于Ca2+与CO2-3反应生成Ca CO3颗粒,故Ca2+离子浓度变化与离子半径和电荷量呈非线性关系。同时提出更全面的水合物法海水淡化中盐离子的排斥机制。较于反渗透传统方法,水合物法具有脱硼效果好的优势。     

Comparison of the removal of monovalent and divalent cations in the microbial desalination cell

Microbial desalination cell (MDC) is a promising technology to desalinate water and generate electrical power simultaneously. The objectives of this study were to investigate the desalination performance of monovalent and divalent cations in the MDC, and discuss the effect of ion characteristics, ion concentrations, and electrical characteristics. Mixed salt solutions of NaCl, MgCl₂, KCl, and CaCl₂ with the same concentration were used in the desalination chamber to study removal of cations. Results showed that in the mixed salt solutions, the electrodialysis desalination rates of cations were: Ca²⁺ >Mg²⁺>Na⁺>K⁺. Higher ionic charges and smaller hydrated ionic radii resulted in higher desalination rates of the cations, in which the ionic charge was more important than the hydrated ionic radius. Mixed solutions of NaCl and MgCl₂ with different concentrations were used in the desalination chamber to study the effect of ion concentrations. Results showed that when ion concentrations of Na⁺ were one-fifth to five times of Mg²⁺, ion concentration influenced the dialysis more profoundly than electrodialysis. With the current densities below a certain value, charge transfer efficiencies became very low and the dialysis was the main process responsible for the desalination. And the phosphate transfer from the anode chamber and potassium transfer from the cathode chamber could balance 1%–3% of the charge transfer in the MDC.