王588块泥浆污染深穿透酸液研究与评价     

胡增国 《海洋地质译丛》2010,(2):58-62,71

王588块钻井泥浆污染主要是固相入侵和滤液与地层水的不配伍性。通过实验,优选出了具有高效深穿透能力以及固相溶解量大的表面活性剂DS-101酸液复配体系。实验表明,该体系耐温性强,对油泥具有极强的分散和溶解作用,对泥浆污染有明显的解堵效果,岩心渗透率恢复率可达127%。  相似文献   

河北保定岩溶地热结垢过程模拟及防垢对策     

何雨江  刘肖  邢林啸  谭现锋  卜宪标 《地学前缘》2022,29(4):430-437

我国的地热发电以及部分供暖工程出现了比较严重的结垢现象,阻碍了地热能的大规模开发利用,目前地热市场急需成熟的防垢理论和工艺。地热工程的结垢现象尤以碳酸钙结垢最为普遍,为解决碳酸钙结垢问题,本文以华北保定岩溶地热井结垢为研究对象,通过理论和实验相结合的手段研究分析了垢质成分,成垢机理,结垢位置和过程以及防垢措施。研究结果表明:(1)系统降压造成的闪蒸是碳酸钙结垢的主因,液相二氧化碳逸出到气相是碳酸钙结垢的主要驱动力;(2)根据井口参数,结合质量、动量和能量守恒以及两相流压降理论,可以模拟结垢过程,确定结垢位置以及不同深度处的压力、温度、干度和二氧化碳分压等参数;(3)闪蒸造成的碳酸钙结垢,确定了闪蒸位置和闪蒸压力后,可以通过加压和加注阻垢剂的方式进行阻垢。通过模拟计算,确定了加压防垢系统所需的最低压力,通过控制系统压力可防止闪蒸,抑制二氧化碳逸出造成的结垢。设计了阻垢工艺,研制了阻垢剂加注设备,开展了井下化学阻垢实验并评价了阻垢效果,通过加注阻垢剂可有效阻止90%以上的垢生成,论证了通过加注化学阻垢剂可以有效解决碳酸钙结垢。通过上述研究,积累了从结垢原因分析,结垢位置确定,结垢过程模拟,防垢工艺和设备研发,防垢实践到阻垢效果现场评价一整套经验,可为其他地热井碳酸钙结垢问题的解决提供参考依据。  相似文献   

Magnetic cleansing of weathered/tarry oiled feathers--the role of pre-conditioners     

Dao HV  Ngeh LN  Bigger SW  Orbell JD  Healy M  Jessop R  Dann P 《Marine pollution bulletin》2006,52(12):1591-1594

Iron powder has previously been demonstrated to be effective in the removal, via magnetic harvesting, of a wide variety of oil contaminants from feathers and plumage. This study investigates the efficacy of magnetic cleansing for the removal from feathers of tarry contamination that has been allowed to weather. Clusters of feathers from Mallard duck (Anas platyrhnchos) and Little Penguin (Eudyptula minor) were completely immersed in a tarry contaminant and allowed to weather from one to fourteen days. The contaminant was removed using a magnetic cleansing protocol and the removal efficacy assessed gravimetrically. For one, seven and fourteen days of weathering, a final removal (after fourteen treatments) of more than 99% and 97% was achieved for duck feathers and penguin feathers, respectively. Repeating the experiments (for a seven-day weathering period) for both duck and penguin feathers, with the judicious application of a pre-conditioner (olive oil), further improved removal efficacy. A convenient method to screen for improved pre-conditioning agents is suggested.  相似文献   

提高生态浮床系统脱氮除磷效率研究进展   总被引：3，自引：0，他引：3  

汪开英  郑水生  郭宗楼  徐文彬 《湿地科学》2012,10(1):116-120

生态浮床系统处理技术因具有投资少、易操作、无二次污染兼具良好景观性等优点而被广泛应用于各种类型污染水体的治理。生态浮床系统是一个复合生态工程系统,其对污染的去除机理是一个错综复杂的过程,填料、水生植物、水生动物和微生物共同发挥着重要作用。主要概述生态浮床系统的发展状况、脱氮除磷机理、限制因素及存在问题;重点概述以细菌固定化技术和曝气等方式的外在法和以改进生态浮床系统构造形式、筛选优势浮床植物等方式的内在法,来提高生态浮床系统脱氮除磷效率;展望了生态浮床污水处理系统未来的研究与应用前景。  相似文献   

“麦莎”远距离台风暴雨的排熵指数分析   总被引：5，自引：0，他引：5  

李春虎  罗哲贤  张颖娴  王咏青  崔粉娥 《南京气象学院学报》2008,31(3):381-388

对2005年8月5日山东省一次远距离台风暴雨过程进行了诊断分析。从引起远距离台风暴雨的几个因素,分析此次山东地区强降水过程与台风“麦莎”及中纬度西风带系统的关系,判别台风暴雨的类型;应用耗散结构理论,分析了排熵指数与远距离台风暴雨区的关系。结果表明：该次暴雨过程是在远距离台风（0509号“麦莎”台风）和西风槽相互作用下产生的;非纬向的高、低空急流对本次暴雨过程起着重要作用;负熵变区（IRE〈0）对应着暴雨区,负熵变区的汇合反映远距离台风暴雨的落区,排熵指数对远距离台风暴雨分析预报有一定的指示作用。  相似文献   

纳米铁去除饮用水中As(Ⅲ)和As(Ⅴ)   总被引：3，自引：1，他引：2  

黄园英  秦臻  刘菲 《岩矿测试》2009,28(6):529-534

在好氧水体中,As(Ⅲ)比As(Ⅴ)更易迁移,而且在水处理过程中去除效率更低。在实验室合成制得BET比表面积为49.16 m2/g,直径范围为20~40 nm的纳米铁。通过批试验考察纳米铁对As(Ⅲ)和As(Ⅴ)去除能力及其反应动力学情况。结果表明,在pH为7,温度20℃时纳米铁能够快速地去除As(Ⅲ)和As(Ⅴ),在60 m in内,0.25 g纳米铁对起始浓度为968.6μg/L As(Ⅲ)和828.9μg/L As(Ⅴ)的去除率大于99.5%。反应遵循准一级反应动力学方程,标准化后的As(Ⅲ)和As(Ⅴ)比表面积速率常数kSA分别为1.30 mL/(m2.m in)和1.64 mL/(m2.m in)。由实验结果可知,具有高反应活性的纳米铁是用于含砷饮用水处理非常有效的吸附材料。  相似文献   

11 Å tobermorite from cement bypass dust and waste container glass: A feasibility study     

N.J. Coleman  C.J. Trice  J.W. Nicholson 《International Journal of Mineral Processing》2009,93(1):73-78

A novel one-step hydrothermal synthesis of 11 Å tobermorite, a cation exchanger, from a unique combination of waste materials is reported. 11 Å tobermorite was prepared from stoicheiometric quantities of cement bypass dust and waste container glass at 100 °C in water. The product also comprised 10 wt.% calcite and trace quartz as residual parent phases from the cement bypass dust. In a batch sorption study at 20 °C the uptakes of Cd²⁺ and Pb²⁺ by the waste-derived tobermorite product were found to be 171 mg g^− 1 and 467 mg g^− 1, respectively, and in both cases the removal process could be described using a simple pseudo-second-order rate model (k₂ = 2.30 × 10^− 5 g mg^− 1 min^− 1 and 5.09 × 10^− 5 g mg^− 1 min^− 1, respectively). The sorption characteristics of the 11 Å tobermorite are compared with those of other waste-derived sorbents and potential applications are discussed.  相似文献   

Rejection of arsenic minerals in sulfide flotation — A literature review     

X. Ma  W.J. Bruckard 《International Journal of Mineral Processing》2009

Arsenic is one of the most dangerous inorganic pollutants and thus a penalty element in many base metal concentrates. Arsenic removal in sulphide flotation has been studied extensively with various approaches, including pre-oxidation of flotation pulp, E_h control during flotation and the use of selective depressants/collectors. Pre-oxidation of flotation pulp using oxidizing agents or aeration conditioning represents a simple approach in arsenic removal and was found effective in many cases. Selective flotation of arsenic minerals through E_h control has made significant advances in recent years with promising results achieved. In addition, various depressants and collectors have also been studied in arsenic removal. In this communication, the various approaches used in selective flotation of arsenic minerals are reviewed with emphasis on the development in recent years.  相似文献   

Channel response to a dam-removal sediment pulse captured at high-temporal resolution using routine gage data     

Matthew J. Cashman  Allen C. Gellis  Eric Boyd  Mathias J. Collins  Scott W. Anderson  Brett D. McFarland  Ashley M. Ryan 《地球表面变化过程与地形》2021,46(6):1145-1159

In this study, we captured how a river channel responds to a sediment pulse originating from a dam removal using multiple lines of evidence derived from streamflow gages along the Patapsco River, Maryland, USA. Gages captured characteristics of the sediment pulse, including travel times of its leading edge (~7.8 km yr⁻¹) and peak (~2.6 km yr⁻¹) and suggest both translation and increasing dispersion. The pulse also changed local hydraulics and energy conditions, increasing flow velocities and Froude number, due to bed fining, homogenization and/or slope adjustment. Immediately downstream of the dam, recovery to pre-pulse conditions occurred within the year, but farther downstream recovery was slower, with the tail of the sediment pulse working through the lower river by the end of the study 7 years later. The patterns and timing of channel change associated with the sediment pulse were not driven by large flow or suspended sediment-transporting events, with change mostly occurring during lower flows. This suggests pulse mobility was controlled by process-factors largely independent of high flow. In contrast, persistent changes occurred to out-of-channel flooding dynamics. Stage associated with flooding increased during the arrival of the sediment pulse, 1 to 2 years after dam removal, suggesting persistent sediment deposition at the channel margins and nearby floodplain. This resulted in National Weather Service-indicated flood stages being attained by 3–43% smaller discharges compared to earlier in the study period. This study captured a two-signal response from the sediment pulse: (1) short- to medium-term (weeks to months) translation and dispersion within the channel, resulting in aggradation and recovery of bed elevations and changing local hydraulics; and (2) dispersion and persistent longer-term (years) effects of sediment deposition on overbank surfaces. This study further demonstrated the utility of US Geological Survey gage data to quantify geomorphic change, increase temporal resolution, and provide insights into trajectories of change over varying spatial and temporal scales.  相似文献   

Experimental study on the effect of bottomless structure in front of a bottom outlet on a sediment flushing cone     

Hadi Haghjouei  Majid Rahimpour  Kourosh Qaderi  Sameh AKantoush 《国际泥沙研究》2021,36(3):335-347

One of the main problems in reservoirs is sedimentation which reduces the operating life of dams if a proper plan and analysis method are not in place.The techniques to manage sediment in reservoirs include several sustainable management techniques that route sediment through or around the reservoir.One of the main economical methods in arid and semi-arid regions is pressurized flushing using moderate drawdown of the water level of the reservoir to evacuate sediment deposited behind dams.In the current study,the effect of a new structure called a dendritic bottomless extended(DBE)outlet structure at three angles of 30°,45°,and 60°
on pressurized flushing efficiency was investigated.Consequently,45 experiments were designed for three discharge rates (Qo),three sediment levels(Hs),four types of structure,and a no-structure condition(reference test).The results indicated that the DBE structure with a 30°angle between the branches,a sedimentary dimensionless index of Hs/Do=4.59,and a flow dimensionless index of Qo=/√gD05=1:43(where g is the acceleration of gravity and Do is the diameter of the bottom outlet)lead to 10-fold increase in the sediment flushing cone dimensions and sediment removal efficiency compared to the results of the reference test.Finally,according to a statistical analysis of the results,a dimensionless equation for calculating the sediment flushing cone dimensions was developed for the tested sediment characteristics.  相似文献