海上油田含油污泥对污泥-聚合物混合液性能的影响

为了回注处理海上油田含油污泥,将其与聚合物溶液混合,制备聚合物驱调剖体系。系统评价了含油污泥对污泥-聚合物混合液的溶液性能、使用性能及驱油效果的影响。实验结果表明:当含油污泥浓度小于300 mg/L时,油泥颗粒的粒径范围为0.1~100μm,d_(90)为40~60μm,污泥-聚合物混合液的黏度、抗剪切及抗老化稳定性均得到增强,注入性不受显著影响,阻力系数及残余阻力系数略有增加;当采用油泥浓度为100 mg/L的污泥-聚合物混合液进行驱油实验时,聚驱采收率增幅为7.26百分比,然而含油污泥浓度的进一步升高对提高采收率并不利。     

Conceptual Framework for the National Flood Interoperability Experiment

The National Flood Interoperability Experiment is a research collaboration among academia, National Oceanic and Atmospheric Administration National Weather Service, and government and commercial partners to advance the application of the National Water Model for flood forecasting. In preparation for a Summer Institute at the National Water Center in June‐July 2015, a demonstration version of a near real‐time, high spatial resolution flood forecasting model was developed for the continental United States. The river and stream network was divided into 2.7 million reaches using the National Hydrography Dataset Plus geospatial dataset and it was demonstrated that the runoff into these stream reaches and the discharge within them could be computed in 10 min at the Texas Advanced Computing Center. This study presents a conceptual framework to connect information from high‐resolution flood forecasting with real‐time observations and flood inundation mapping and planning for local flood emergency response.     

Marshaling Adaptive Capacities within an Adaptive Management Framework to Enhance the Resiliency of Wastewater Systems

We assess adaptive capacity and adaptive management as measures of wastewater (WW) system resiliency using data from interviews with WW system managers (hereafter managers) impacted by past storms. Results suggest the most resilient WW systems are those with high adaptive capacities that employ an adaptive management approach to make ongoing adaptation investments over time. Greater amounts of generic adaptive capacities (i.e., skilled staff and good leadership) help smooth both day‐to‐day and emergency operations and provide a foundation for adaptive management. In turn, adaptive management helps managers both build more generic adaptive capacities, and develop and employ greater amounts and diversity of specific adaptive capacities (i.e., soft and/or hard adaptations) that are especially important for enhancing and sustaining resiliency. Adaptive management also enables managers to better understand their system's vulnerabilities, how those vulnerabilities change over time, and what specific actions may reduce those vulnerabilities. Finally, our work suggests WW system resilience critically depends on the capacities of the human systems for building resilience as much as or more so than relying only on physical infrastructure resilience. Our work contributes to filling an important gap in the literature by advancing our understanding of the human dimensions of infrastructure resilience and has practical implications for advancing resilience in the WW sector.     

蒸汽抑制熄灭酒精池火有效性的模拟实验研究

蒸汽灭火系统在酒类作业场所有着广阔的应用前景.通过全淹没和局部保护实验对蒸汽抑制熄灭酒精池火的有效性进行了研究.实验结果表明,全淹方式难以有效控火,但是布局合理的局部保护方式能够有效熄灭酒精池火.蒸汽灭火过程中稀释O2浓度的灭火机理起到的作用较小,蒸汽的火焰拉伸效果是其主导灭火机理.     

Hydrologic Modeling of an Extreme Flood in the Guadalupe River in Texas1

Sharif, Hatim O., Almoutaz A. Hassan, Sazzad Bin-Shafique, Hongjie Xie, and Jon Zeitler, 2010. Hydrologic Modeling of an Extreme Flood in the Guadalupe River in Texas. Journal of the American Water Resources Association (JAWRA) 1-11. DOI: 10.1111/j.1752-1688.2010.00459.x Abstract: Many of the storms creating the greatest rainfall depths in Texas, measured over durations ranging from one minute to 48 hours, have occurred in the Texas Hill Country area. The upstream portion of the Guadalupe River Basin, located in the Texas Hill Country, is susceptible to flooding and rapid runoff due to thin soils, exposed bedrock, and sparse vegetation, in addition to the Balcones Escarpment uplift contributing to precipitation enhancement. In November 2004, a moist air mass from the Gulf of Mexico combined with moist air from the Pacific Ocean resulted in the wettest November in Texas since 1895. Although the peak discharges were not the highest on record, the U.S. Geological Survey (USGS) stream gauge on the Guadalupe River at Gonzales, Texas reported a daily mean discharge of 2,304 m³/s on November 23, 2004 (average discharge is 53 m³/s). In this paper, we examine the meteorological conditions that led to this event and apply a two-dimensional, physically based, distributed-parameter hydrologic model to simulate the response of a portion of the basin during this event. The study results clearly demonstrate the ability of physically based, distributed-parameter simulations, driven by operational radar rainfall products, to adequately model the cumulative effect of two rainfall events and route inflows from three upstream watersheds without the need for significant calibration.     

Heterogeneity of Hydrologic Response in Urban Watersheds1

Meierdiercks, Katherine L., James A. Smith, Mary Lynn Baeck, and Andrew J. Miller, 2010. Heterogeneity of Hydrologic Response in Urban Watersheds. Journal of the American Water Resources Association (JAWRA) 46(6):1221–1237. DOI: 10.1111/j.1752-1688.2010.00487.x Abstract: The changing patterns of streamflow associated with urbanization are examined through analyses of discharge and rainfall records for the study watersheds of the Baltimore Ecosystem Study (BES). Analyses utilize a decade (1999-2008) of observations from a dense U.S. Geological Survey stream gaging network and Hydro-NEXRAD radar rainfall fields. The principal study watershed of the BES is Gwynns Falls (171 km²). Focus is given to two Gwynns Falls basins with contrasting patterns and histories of development, Dead Run and Upper Gwynns Falls. The sharp contrasts in streamflow properties between the basins reflect the differences in urban development prior to implementation of stormwater management regulations (much of Dead Run) and development for which stormwater management is an integral part of the hydrologic system (Upper Gwynns Falls). The mean annual runoff in Dead Run (558 mm) is 35% larger than that of Upper Gwynns Falls; larger contrasts in runoff properties typify the “warm season” and are linked to storm event hydrologic response. Spatial heterogeneities in storm event response are reflected in seasonal and diurnal properties of streamflow. Analyses of storm event response are presented for June 2006, during which monthly rainfall over the BES region ranged from less than 150 to more than 500 mm. Baisman Run, the BES forest reference watershed, and Moores Run, a highly urbanized watershed in Baltimore City, provide “end-member” representations of urban impacts on streamflow.     

二元驱污水配聚黏损影响因素分析及控制方法

含油污水中活泼金属离子会对聚合物产生不同程度的降解,导致注入液的黏度损失较大。室内试验表明:水中二价铁、二价硫及硫化亚铁在溶解氧存在的情况下,均会大幅降低聚合物溶液的黏度,0.5mg/L的二价铁或二价硫、1mg/L的硫化亚铁,黏度损失在15%左右。溶解氧为5.17mg/L时,加入9mg/L的二价铁,聚合物溶液的黏度仅为5.48mPa.s,黏度损失超过95%。为减少上述因素对聚合物黏度的影响,利用陈化法、曝气法及化学氧化法等方法均能有效降低含油污水配聚过程中的黏度损失率。     

A Decade of Geomorphic and Hydraulic Response to the La Valle Dam Project,Baraboo River,Wisconsin

We investigate stream response to the La Valle Dam removal and channel reconstruction by estimating channel hydraulic parameter values and changes in sedimentation within the reservoir. The designed channel reconstruction after the dam removal included placement of a riffle structure at the former dam site. Stream surveys undertaken in 1984 by Federal Emergency Management Agency and in 2001 by Doyle et al. were supplemented with surveys in 2009 and 2011 to study the effects of the instream structure. We created a model in HEC‐RAS IV and surface maps in Surfer© using the 1984, 2009, and 2011 surveys. The HEC‐RAS IV model for 2009 channel conditions indicates that the riffle structure decreases upstream channel shear stress and velocity, causing renewed deposition of sediment within the former reservoir. We estimate by 2009, 61% of former reservoir sediments were removed during dam removal and channel reconstruction. Between 2009 and 2011 renewed sedimentation within the former reservoir represented approximately 7.85% of the original reservoir volume. The HEC‐RAS IV models show the largest impacts of the dam and riffle structure occur at flood magnitudes at or below bankfull. Thus, the riffle and the dam similarly alter channel hydraulics and sediment transport. As such, our models indicate that the La Valle Dam project was a dam replacement rather than a removal. Our results confirm that channel reconstruction method can alter channel hydraulics, geomorphology, and sediment mobility.     

A Framework to Develop Nationwide Flooding Extents Using Climate Models and Assess Forecast Potential for Flood Resilience

The methods used to simulate flood inundation extents can be significantly improved by high‐resolution spatial data captured over a large area. This paper presents a hydraulic analysis methodology and framework to estimate national‐level floodplain changes likely to be generated by climate change. The hydraulic analysis was performed using existing published Federal Emergency Management Agency 100‐year floodplains and estimated 100‐ and 10‐year return period peak flow discharges. The discharges were estimated using climate variables from global climate models for two future growth scenarios: Representative Concentration Pathways 2.6 and 8.5. River channel dimensions were developed based on existing regional United States Geological Survey publications relating bankfull discharges with channel characteristics. Mathematic relationships for channel bankfull topwidth, depth, and side slope to contributing drainage area measured at model cross sections were developed. The proposed framework can be utilized at a national level to identify critical areas for flood risk assessment. Existing hydraulic models at these “hot spots” could be repurposed for near–real‐time flood forecasting operations. Revitalizing these models for use in simulating flood scenarios in near–real time through the use of meteorological forecasts could provide useful information for first responders of flood emergencies.     

A HYDROCLIMATOLOGICAL ANALYSIS OF THE RED RWER OF THE NORTH SNOWMELT FLOOD CATASTROPHE OF 19971

ABSTRACT: The flood hydroclimatology of the Grand Forks flood of April 1997, the most costly flood on a per capita basis for a major metropolitan area in United States history, is analyzed in terms of the natural processes that control spring snowmelt flooding in the region. The geomorphological characteristics of the basin are reviewed, and an integrated assessment of the hydroclimatological conditions during the winter of 1996 to 1997 is presented to gain a real‐world understanding of the physical basis of this catastrophic flood event. The Grand Forks flood resulted from the principal flood‐producing factors occurring at either historic or extreme levels, or at levels conducive to severe flooding. Above normal fall precipitation increased the fall soil moisture storage and reduced the spring soil moisture storage potential. A concrete frost layer developed that effectively reduced the soil infiltration capacity to zero. Record snowfall totals and snow cover depths occurred across the basin because of the unusual persistence of a blocking high circulation pattern throughout the winter. A severe, late spring blizzard delayed the snowmelt season and replenished the snow cover to record levels for early April. This blizzard was followed by a sudden transition to an extreme late season thaw due to the abrupt breakdown of the blocking circulation pattern. The presence of river ice contributed to backwater effects and affected the timing of tributary inflows to the main stem of the Red River. Only the absence of spring rains prevented an even more catastrophic flood disaster from taking place. This paper contributes to our understanding of the flood hydroclimatology of catastrophic flood events in an unusual flood hazard region that possesses relatively flat terrain, a north‐flowing river, and an annual peak discharge time series dominated by spring snowmelt floods.