酸阻滞技术的研究与应用

本文提出酸阻滞法从废液中分离，回收重金属和酸的新技术工艺，从十多种国产树脂中成功地筛选出两种可作为酸阻滞剂，有较好的分离效果。但洗脱时酸脱尾严重，当选择穿透比在０．６左右时，可以解决酸脱尾现象，使脱尾酸损失由３０％降到７％，而酸的回收率由６０％提高到９０％，采用该工艺对几种废液进行处理，重金属回收液中酸去除率大于９５％，而回用酸中金属去除率大于７０％，该工艺既可回收重金属，同时也可回收酸。     

H型钢冷却过程的数值分析

此文根据非稳定热传导基本方程式积分得到离散化方程式,编写出计算程序.利用计算机求出H型钢内各点随时间变化的温度,绘出等温线,以研究H型钢理想的冷却方法.     

石墨炉原子吸收分光光度法测定城市交通干道空气中的铅

用超细玻璃纤维滤膜收集城市交通干道空气中的铅,硝化后使用石墨 炉原子吸收分光光度法测定。本方法具有灵敏度高,精密度和准确度较好等优点。铅平均浓度在10.57-69.67ug/L时,其相对偏差在0.47%-5.7%,标准差在0.185-0.33%之间,CV在0.47%-3.03%之间,标准曲线的相关系数为0.998.     

EFFECT OF A POINT SOURCE INPUT ON STREAM NUTRIENT RETENTION1

ABSTRACT: We examined the effect of a point source (PS) input on water chemistry and nutrient retention in Spavinaw Creek, Arkansas, during summer baseflows in 1998 and 1999. The nutrient uptake length (S_w) concept was used to quantify the impact of nutrient inputs in the receiving stream. We used an artificial injection upstream of the PS inputs to estimate background S and used the natural decline in nutrient concentrations below the PS to estimate the net nutrient uptake length (S_net). S_w for soluble reactive phosphorus (SRP) in the upstream reference section was O.75 km, but S_net ranged from 9.0 to 31 km for SRP and 3.1 to 12 km for NO₃‐N in the reach below the PS. S_net‐SRP was significantly correlated with discharge whereas S_net‐NO₃‐N was correlated with the amount of NO₃‐N enrichment from the PS. In order to examine specific mechanisms of P retention, loosely exchangeable P and P Sorption Index (PSI) of stream sediments were measured. Sediments exhibited little natural P buffering capacity (low PSI) above the PS, but P loading from the PS further reduced PSI. Loosely exchangeable P in the sediments also increased three fold below the PS, indicating sediments removed some water column P. The physical process of flow and sediment sorption apparently regulated P retention in Spavinaw Creek, whereas the level of N enrichment and possibly biotic uptake and denitrification influenced N retention. Regardless of the mechanism, Spavinaw Creek demonstrated little ability to retain PS‐added nutrients because net nutrient uptake lengths were in the km range.     

凡口铅锌矿主井(箕斗井)入风净化实践

介绍了凡口铅锌矿主井(箕斗井)入风净化方案和净化系统及使用情况.     

区域点源和非点源磷入河量计算的二元统计模型

基于流域或区域点源和非点源磷入河过程的水文学差异,以及影响河流持留作用的主要机制,建立了描述河流段末磷负荷量与流量和水温之间定量关系的二元统计模型;通过逐月的河流水文水质监测数据对模型中4个系数的有效校正和验证,实现了对点源和非点源磷入河过程的准确定量.与现行的水文估算法相比,该模型既考虑了河流磷的持留能力及其时间变异性,也考虑了上游水体输入的磷负荷量,推进了对磷污染过程的定量认识,满足了我国以行政区为主要水污染控制管理单元的现实需要.应用该模型,计算了浙江长乐江集水区2004～2009年的总磷(TP)入河量.结果表明,TP年入河总量为(54.6±11.9)t.a-1,其上游水体输入、点源和非点源的入河量贡献率分别为5%±1%、12%±3%和83%±3%.夏季5～6月和8～9月的非点源TP累计入河量占其全年的50%±9%,增加了引起下游水体藻类暴发的风险.河流TP持留量为(4.5±0.1)t.a-1,占年入河总量的9%±2%;5～9月的TP累计持留量占全年的55%±2%,表明河流持留能力对流域或区域磷素迁移转化过程的调控作用不容忽视.本研究建立的二元统计模型仅需常规的河流水文水质监测数据,无需专业软件知识,且计算结果直接来源于实际的河流水文水质测算值,为实施流域或区域磷污染总量控制策略提供了一种简便、实用、可靠的定量工具.     

大落差原油管道投产充水过程研究

为了探究大落差管道充水投产过程中存在的不满流及低点超压问题,以中缅原油管道怒江跨越段为例（其最大高差达1 480 m）,基于OLGA多相流瞬态模拟方法,对大落差原油管道充水过程进行仿真研究,重点分析到达管道不同低点位置的最大速度、压力及相应持液率,得到不同输量条件下不同低点位置的水流速度、压力及持液率随时间变化规律。结果表明:当输量为900~2 000 m3/h时该管道中存在的段塞流概率降低57%,同时减少了管压波动以及对管道和设备的破坏,提高了管道输送效率。     

基于Monte Carlo的海洋平台圆柱落物落点分析及危险区快速评价*

为实现海洋平台落物风险快速精确评价,针对传统推荐性规范经验化、过于简化、平面化及未体现工程随机性等问题,以圆柱落物为研究对象开展先导研究,基于3D运动理论模型,提出1种采用Monte Carlo方法表征工程随机性以实现危险区快速精确评价的方法,自主开发形成海洋平台圆柱落物危险区快速评价工具（MREDP）,着重分析落点分布规律和危险区等级划分。结果表明:落点分布整体呈现“倒工字圆弧型”、两端“一密一疏”、关于X轴对称特点;MREDP快速评价结果可信,评价周期大幅降低;MREDP快速评价危险区相对较大、存在多峰值点,DNVGL-RP-F107推荐危险区相对保守、存在单峰值点。     

Image rotation method for identification of NPW signals in the localization of pipeline leakage

Gas and oil are mainly transported through long-distance pipelines on land. Pipeline leaks lead to severe hazards to the environment and economy and even imperil human lives. Negative pressure wave (NPW)-based methods are fast and effective for leak monitoring and localization. The key problem for an NPW-based method is to determine the NPW and its arrival time, which is characterized by the knee point in the time domain signal. In this paper, an image rotation method is proposed based on the shape characteristic of the time domain signal induced by an NPW. Through image rotation, the knee point turns into the highest point, which is easy to detect. To verify the performance of the proposed method, leakage experiments were conducted on liquid and gas pipeline models. Previously developed FBG pipe fixture sensors were used to detect an NPW. These sensors were equidistantly installed on the pipeline, forming a sensor array. Based on the sensing array, a novel leak localization algorithm was used to compute the leakage position. The experimental results indicated that the image rotation method has good performance for identifying an NPW, even though many noise- and pressure-induced fluctuations exist in the signals. This method enables automated real-time monitoring and has potential for practical application.     

Mixing Zone Characterization of Two Transition Terrain Streams With Tracers1

Abstract: For most wastewater discharges to streams, the effluent creates a plume that becomes less distinct as it mixes with the receiving water. Constant‐discharge tracer studies were used to characterize the plume or physical mixing zone (PMZ) at two similar transition terrain streams. At both sites, the laterally unmixed PMZs did not extend across the entire stream and mixing occurred relatively quickly. The observed plumes were significantly smaller than the regulatory mixing zone (RMZ) allowed by the State of Colorado. At Site 1 mixing occurred within a much shorter distance due to the presence of a riffle zone located a few meters downstream of the discharge point. Interpretation of field data with an analytical model suggests that the effective transverse dispersion coefficient (k_z) for the riffle zone at Site 1 (～1 m²/s) was significantly higher than the average value over the longer nonriffle section at Site 2 (～0.01 m²/s). These results imply that to achieve the fastest mixing in transition terrain streams, thereby minimizing the size of the PMZ, discharge outfalls should be located upstream and close to riffle zones.