废水生物除磷技术综述

介绍和评述了生物除磷的两种机理,基于两种机理的除磷工艺,指出了它们的特点,探讨了今后除磷技术的发展方向.     

改良型透水铺装对弱透水土质地区的水质控制试验

为改善透水铺装在弱透水土质地区的应用,通过增加渗透导管的方式改良了常规透水铺装的土基层。通过人工降雨试验对改良型透水铺装及其不同结构层对弱透水土质地区典型雨水径流中COD、TN、TP和Cu~(2+)等污染物的去除效果进行了分析,并与相同条件下的常规透水铺装进行了对比。结果表明,改良型透水铺装对4种污染物的去除效果有明显增强,在60 min降雨历时条件下,降雨重现期为2 a时改良型透水铺装对4种污染物的去除能力分别提升了11.87%、27.61%、9.17%和29.02%,且降雨重现期越短越有利于透水铺装对COD、TN、TP和Cu~(2+)的去除。     

Population effect of a large‐scale stream restoration effort on Chinook salmon in the Pahsimeroi River,Idaho

Stream habitat restoration is an important tool for fisheries management in impaired lotic systems. Although small‐scale benefits of stream habitat restoration are commonly investigated, it is difficult to demonstrate population effects. The Pahsimeroi River Chinook salmon Oncorhynchus tshawytscha population was previously restricted to the lower portion of the river by multiple irrigation structures. To address fish passage issues, a combination of restoration projects was initiated including barrier removals, instream flow enhancements and installation of fish screens on diversions. The largest barrier was removed in 2009, more than doubling the amount of accessible linear habitat. We hypothesized restoration efforts would expand the distribution of spawning salmon in the Pahsimeroi River watershed, leading to a broader distribution of juveniles. We also hypothesized a broader juvenile distribution would have population effects by reducing the prevalence of density‐dependent growth and survival. Redds were documented in newly accessible habitat immediately following barrier removal and accounted for a median of 42% of all redds in the Pahsimeroi River watershed during 2009–2015. Snorkel surveys also documented juvenile rearing in newly accessible habitat. Juvenile productivity increased from a median of 64 smolts/female spawner for brood years 2002–2008 to 99 smolts/female spawner for brood years 2009–2014. Overall, results suggested increased habitat accessibility in the Pahsimeroi River broadened the distribution of spawning adult and rearing juvenile salmon and reduced the effects of density‐dependent survival. Large‐scale stream restoration efforts can have a population effect. Despite the large‐scale effort and response, habitat restoration alone is likely not sufficient to restore this population.     

浅谈房地产公司战略采购材料部品送认封管理

通过材料部品样品送样、认样、封样的全过程管理,实现材料部品的收集、分类、整理、入库、出库的过程跟踪控制,明确职责划分实施全过程可追溯的有效资源管理模式。     

硫酸盐还原菌分离及其处理煤矿酸性废水工艺的实验研究

针对煤矿酸性废水直接排放污染水资源的问题,试验选用污泥样作为筛选样品富集硫酸盐还原菌,采用稀释涂布-叠皿夹层厌氧培养法分离纯化SRB,研究了SRB对煤矿酸性废水中Fe2+和SO42-的去除效果。试验结果表明:分离纯化得到的SRB符合典型的"S"型生长曲线,SRB的最佳生长条件为34℃、p H为7、70%乳酸钠作为碳源。综合比较接种不同量SRB对煤矿酸性废水的处理效果可知,接种10%SRB的处理效果较好,接种时间为5d时对煤矿酸性废水中SO42-和Fe2+的去除率分别为74. 71%和99. 18%。     

龙潭水库除险加固工程主坝地质条件及评价

本文主要对龙潭水库主坝工程地质条件进行分析,并对其稳定性做出评价,为指导除险加固工程提供一定的依据。通过对坝基的分析与评价,认为大坝坝基及两坝肩基岩较完整,渗透性微弱,水库运行未发现有明显绕渗现象,判定坝基及坝肩渗漏微小,对水库安全运行无影响。     

浅谈如何对沥青拌合站除尘设备进行维护与改进

本文就沥青拌合站除尘设备的工作原理,及对沥青拌合站除尘设备进行维护与改进的办法进行探讨。     

含铁矿物吸附剂除磷机理研究及中试应用

研究了含铁矿物吸附剂吸附含磷废水的各项性能,通过静态试验得出此吸附剂的最佳吸附条件,并以此为依据进行了动态小试试验和中试试验。结果表明,含铁矿物吸附剂的吸附平衡时间为45h,吸附等温线较符合Freundlich方程,pH约为5时吸附量达到最大,除铁离子和铝离子外,水体中无机阴离子和阳离子对磷酸盐的吸附影响不大。用1mol/L的NaOH溶液对饱和吸附剂解吸再生,解吸率达到90%以上。在合适的填充体积和进水流速下,含铁矿物吸附剂连续吸附除磷可以达到良好的效果,中试试验装置连续运行了约105d,出水TP达到了《地表水环境质量标准》(GB3838—2002)(Ⅲ类湖、库)要求。     

中小跨径双曲拱桥拱上建筑最优拆除方案研究

本文以矿山桥(东)为例,综合考虑桥梁所处地理位置和经济成本并利用有限元软件对控制截面进行计算,介绍中小跨径双曲拱桥最优拆除方案,对今后类似桥梁的拆除工程具有借鉴意见。     

TNT炸药废水三维电解氧化实验研究

以不锈钢作为阳极的三维电解反应器对废水的实验研究表明:在最佳电解条件下(极板间距4 cm、电压15 V、pH为3,绝缘粒子与活性炭粒子质量比为0.3,电流强度0.15 A时),电解3 h后TNT和COD的去除率分别为93 %和78 %.并探讨了电化学氧化处理TNT废水的机理.