三亚河沉积物PAHs和PCBs的分布、来源及风险评价

多环芳烃（PAHs）和多氯联苯（PCBs）具有"三致"特性和生物累积效应,作为两类典型持久性有机污染物,是环境领域的研究热点之一.本研究考察了三亚河底泥沉积物中PAHs和PCBs的含量分布和污染状况,在对其进行空间污染分布分析的基础上进行来源解析,并采用沉积物质量基准法和质量标准法进行生态风险评价.结果表明,沉积物中总PAHs和总PCBs含量范围分别为265.00~6735.00 μg·kg^-1和1.75~92.75 μg·kg^-1,含量相对较高河段分别为西河上游和东河上游,与研究区域的工业分布和河流走势有较强的相关性.组成及来源解析表明,PAHs以低环芳烃为主,主要来源于石油燃烧污染;PCBs以七氯联苯和六氯联苯为主,主要来源于电容器中PCBs的迁移.生态风险评价结果表明,整体上三亚河沉积物中PAHs生物毒副作用不明显,生态风险较低,但个别采样点PAHs单体超标严重,对生物体暴露会产生严重威胁,需引起重视;PCBs生物毒性效应概率为10%~50%,偶尔会产生负面生态效应.     

Identical full-scale biogas-lift reactors (BLRs) with anaerobic granular sludge and residual activated sludge for brewery wastewater treatment and kinetic modeling

Two identical full-scale biogas-lift reactors treating brewery wastewater were inoculated with different types of sludge to compare their operational conditions, sludge characteristics, and kinetic models at a mesophilic temperature. One reactor （R1） started up with anaerobic granular sludge in 12 weeks and obtained a continuously average organic loading rate （OLR） of 7.4 kg chemical oxygen demand （COD）/（m3.day）, COD removal efficiency of 80%, and effluent COD of 450 mg/L. The other reactor （R2） started up with residual activated sludge in 30 weeks and granulation accomplished when the reactor reached an average OLR of 8.3 kg COD/（m^3·day）, COD removal efficiency of 90%, and effluent COD of 240 mg/L. Differences in sludge characteristics,biogas compositions, and biogas- lift processes may be accounted for the superior efficiency of the treatment performance of R2 over R1. Grau second-order and modified StoverKincannon models based on influent and effluent concentrations as well as hydraulic retention time were successfully used to develop kinetic parameters of the experimental data with high correlation coefficients （R2 〉 0.95）, which further showed that R2 had higher treatment performance than R1. These results demonstrated that residual activated sludge could be used effectively instead of anaerobic granular sludge despite the need for a longer time.     

新型混凝剂处理印染废水的实验研究

采用自行制备的具有不同SiO2 :Al:Fe(摩尔比值 )和碱化度的两类新型无机高分子混凝剂聚硅酸氯化铝铁 (PSAFC)和聚硅酸硫酸铝铁 (PSAFS)各 7种 ,直接对印染废水进行处理。从中选出 2种混凝剂 ,考察了pH值、混凝剂投量等对混凝效果的影响 ,并对混凝处理后 ,印染废水出水中残留混凝剂主要成分Al、Fe、SiO2 的含量进行分析。实验结果表明 ,氯化物型 (PSAFC)和硫酸盐型 (PSAFS)混凝剂对印染废水的色度、浊度、CODCr均有良好的去除效果 ;总体而言 ,PSAFS的混凝效果略优于PSAFC ;混凝处理后印染废水出水中残留铝、铁、硅的含量均比较低 ;pH值和碱化度对混凝剂在水体中残留铝含量有影响     

机械卷载和余氯对渔业资源损失量评估初探

火(核)电厂、液化天然气(LNG)接收站排放余氯水和取水机械卷载效应均对渔业资源带来影响.本文以LNG接收站工程为例,依据2004年5、8、11月和2005年5月评价水域渔业调查资料,采用渔业资源尾数密度(包括鱼卵、仔鱼生长形成的部分)、受影响的面积和鱼类商品体重的乘积作为计算模式,评估机械卷载和余氯对渔业资源的损失量.结果表明,LNG接收站余氯和机械卷载引起的渔业资源损失量为176.0t/a.本文所采用的评估方法,有助于解决海洋工程影响渔业资源数量评估的实践问题,对渔业资源物损评价标准的制定有一定的参考价值.     

收获后不同小麦品种土壤硝态氮残留量的差异研究

研究不同小麦品种收获后土壤中硝态氮残留量的差异，及其影响因素，对１２个冬小麦品种的研究证明，在低氮和高氮两个施氮处理中，硝态氮残留量均表现明显的品种间差异。     

Effects of advanced oxidation pretreatment on residual aluminum control in high humic acid water purification

Due to the formation of disinfection by-products and high concentrations of Al residue in drinking water purification, humic substances are a major component of organic matter in natural waters and have therefore received a great deal of attention in recent years. We investigated the effects of advanced oxidation pretreatment methods usually applied for removing dissolved organic matters on residual Al control. Results showed that the presence of humic acid increased residual Al concentration notably. With 15 mg/L of humic acid in raw water, the concentrations of soluble aluminum and total aluminum in the treated water were close to the quantity of Al addition. After increasing coagulant dosage from 12 to 120 mg/L, the total-Al in the treated water was controlled to below 0.2 mg/L. Purification systems with ozonation, chlorination, or potassium permanganate oxidation pretreatment units had little effects on residual Al control; while UV radiation decreased Al concentration notably. Combined with ozonation, the effects of UV radiation were enhanced. Optimal dosages were 0.5 mg O3/mg C and 3 hr for raw water with 15 mg/L of humic acid. Under UV light radiation, the combined forces or bonds that existed among humic acid molecules were destroyed; adsorption sites increased positively with radiation time, which promoted adsorption of humic acid onto polymeric aluminum and Al(OH)3(s). This work provides a new solution for humic acid coagulation and residual Al control for raw water with humic acid purification.     

关于氮肥利用率的思考

应用作者近10年在华北地区冬小麦／夏玉米中氮肥转化与去向的研究资料，对施氮量、产量、氮肥利用、残留、损失关系进行分析；认为简单的氮肥利用率很难反映不同农业生产水平条件下的氮肥利用状况；要准确反映氮肥利用状况，应综合考虑产量水平、氮肥利用、残留及损失的情况。论证了我国氮肥利用率具有很大的变幅，平常所说的30％-35％只是一个整体概念，不能以此来说明我国氮肥损失量大，对环境的污染严重。在我国农业生产中，必须研究解决既能获得尽可能高的产量，又能最大限度地减轻对环境压力的氮肥施用技术及其理论基础，而不应该一味追求多么高的氮肥利用率。     

高氯离子废水COD的吸收测定方法研究

本法基于可定星测定Ｋ２Ｃｒ２Ｏ７和Ｃｌ－的反应产物Ｃｌ２这一原理，在用吸收装置吸收Ｃｌ２后．用碘量法测定余氯，从而消除氯离子的干扰。本法具有较高的准确度和精密度。     

典型农药生产场地DDTs和HCHs残留水平及垂直分布特征

采集我国西南某农药厂场地内不同深度的土壤样品,使用GC-MS分析了土壤中六六六(HCHs)和滴滴涕(DDTs)的残留水平和垂直分布特征。结果表明,土壤HCHs浓度变化范围为nd~90.80mg/kg之间(平均值为3.65mg/kg),土壤的DDTs含量介于nd~465.00mg/kg之间(平均值为11.22mg/kg)。垂向土壤样品分析结果显示,HCHs和DDTs的检出率普遍偏高,检出有机氯农药的最深土层达到了1100cm;虽然HCHs和DDTs在不同采样点的剖面变化规律差异明显,但均表现出较强的垂直迁移能力,这可能与本场地企业生产过程中的车间建设改造有关。总体看来,本研究场地土壤环境遭受了明显的HCHs和DDTs污染,在后续的再开发利用中必须采取相应的控制措施或者治理修复,从而保障环境安全。     

新型复合无机高分子混凝剂——聚硅氯化铝(PASC)的净水效果研究

采用共聚方法制备了系列具有不同碱化度（B）和Al/Si摩尔比的聚硅氯化铝（PASC），比较了它们与聚合氯化铝（PAC）的混凝效果及在处理后水中的残留铝含量，研究了B值和pH值对其残留铝含量的影响情况。探讨了PASC的混凝效果和残留铝含量与Al/Si摩尔比之间的关系。结果表明，PASC较PAC具有更好的混凝效果和较低的残留铝含量。对于高浊度水而言，具有适宜Al/Si摩尔比的PASC才具有良好的混凝效果，但对中、低浊度的地表水和含油废水而言，在实验的Al/Si摩尔比范围内，其值越小，混凝效果就越好。PASC在水体中的残留铝含量随着Al/Si摩尔比的降低和B值的升高而下降。PASC和PAC在中性pH条件下具有最低的残留铝含量。