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1.
苏北近海水动力场及污水稀释扩散的模拟   总被引:2,自引:0,他引:2  
针对苏北辐射沙洲海域,通过数值计算,模拟了其水动力场;并利用实测数据对模拟结果进行了验证,分别就大、小潮情况下的流速、潮位及潮流变化特征进行了分析研究.在潮流场基础上结合苏北辐射沙洲附近海域污水排放情况进一步模拟了陆源排放污水的稀释扩散场,分别就两种典型污水排放量下污染物的稀释扩散范围及污水扩散场作了比较分析.结果表明,正交曲线网格能较好地拟合岸线,利用ADI法离散求解正交曲线坐标系下的控制方程,能够有效地对苏北辐射沙洲水动力场进行模拟;受太平洋前进潮波与黄海驻潮波的影响,苏北辐射沙洲岸外南向近岸流和长江冲淡水入海后形成的北上近岸流在弶港交汇,其水动力场以弶港为中心辐聚辐散,形成向外逸散的放射状150°扇面;涨潮平均流速略大于落潮平均流速,落潮流历时略大于涨潮流历时,形成辐射状定向往复流.利用水动力场基础上建立的污染物输运模型模拟污水的稀释、扩散场等值线分布,并计算污染物的稀释情况.在规划的3 000 m3/h污水排放量下,涨潮阶段,排污口A附近污水沿大丰港附近的深槽稀释扩散,排污口C附近污水自N、NE、E和SE方向扩散,污水稀释度等值线向外海有一定的扩展,但相对不明显;落潮阶段,在苏北南向近岸流和长江冲淡水入海后形成的北上近岸流作用下,包络线向北及向东突起,污水稀释度等值线在落潮过程中达到最大.在规划的5 400 m3/h污水排放量下,排污口附近的稀释度等值线范围明显增大,其中排污口A和B附近稀释度等值线相互包络,落憩时刻污水稀释包络范围达到最大.在小潮过程,污水稀释扩散情况和大潮的潮周期过程较为相似,由于潮流较弱,稀释度范围相对小于大潮情况,各阶段的污水扩散范围变化较大潮时小.苏北近海海域内潮汐强、潮差大,潮间带广阔,排污口附近海域的水动力场对污水有较强的稀释、扩散作用.利用苏北海域的水动力条件及物质输运规律科学地排入污水,充分发挥其自净能力,既可改善海域内水污染状况,促进当地经济的发展,又可节省相应的污水治理费用.因此,探讨该海域的水动力变化特征及污水稀释扩散规律是必要的.  相似文献   

2.
采用二维平面潮流数值模拟的方法对董家口港区尾水排放口位置进行比选研究,预测4个拟选排污口分别在尾水正常排放和事故排放两种工况下各水质污染因子的环境影响范围,并结合水深、动力条件等因素最终选定最优排污口.结果表明:研究海区海流以潮流为主,潮流性质为半日潮流,潮流运动形式以往复流为主,旋转为辅,海域涨落急流向为SW—NE向,整体上西防波堤—LNG码头连线南侧海域的水动力条件较好.经数值模拟预测研究,位于西防波堤南侧的P4排污口所在海域水动力条件活跃,水深条件适宜,有利于物质扩散,且事故条件下对日照海域和日照西施舌种质资源保护区影响小,为较优尾水排放点.同时P4排污口所在海域执行三类水质标准,污水数值模拟结果显示该排污口各污染因子超三类水质标准的面积均小于0.742 km2,NS向扩散距离均小于0.34km,扩散趋势与潮流方向一致,有利于其污染物稀释扩散.本次模拟预测客观地反映了污染物排海后的浓度变化和运动规律,为尾水排海污染物进行总量控制及海洋环境开发管理规划提供了科学依据和技术保障.  相似文献   

3.
本文以渤海湾为例,运用MIKE3 FM数值模拟软件建立了渤海湾天津附近海域海水淡化浓海水与电厂温排水混合排放温盐扩散三维数值模型,开展了浓海水和温排水不同混合比例温盐扩散对比研究。研究结果表明:浓海水与温排水混合排放可以使受纳海域盐升范围显著减小,并且混合比例越高,效果越明显。在温升影响方面,与等量温排水单独排放相比,混合排放会使底层海域温升包络面积增大,表层减小,但当混合比例超过1:30(温排水量约为35 m³/s),表层和底层海域温升包络面积接近于等量温排水单独排放的温升包络面积;综合考虑温盐扩散,当海水淡化浓海水排放量在10×104 m³/d,盐升不超过20时,与温排水混合排放比例超过1:30(温排水量超过35 m³/s),盐度在排放口附近可稀释到背景值,由于混合排放密度变化引起的温度下沉影响几乎可以忽略不计。相关研究结论可为海水淡化浓海水科学排放/推动海水淡化和海洋环境和谐可持续发展提供技术支撑。  相似文献   

4.
长江口水动力及污水稀释扩散模拟   总被引:9,自引:0,他引:9       下载免费PDF全文
利用Delft3D数学模型对长江口水动力条件、上海市现有及拟建排放口污水排放的稀释扩散场进行了模拟。模型利用潮汐数据和排放口附近的现场实测数据进行了率定和验证,分别对丰水期、枯水期的大、小潮情况下的流速场、潮位场及污水扩散场进行了研究。结果表明:长江口的水动力条件有利于污水的稀释扩散;现状排放量对长江口水环境影响不大;但如果污水在排放前不进行一定的处理,规划排放量排人长江口将会严重恶化其水质,特别是枯水期小潮时最为严重。建议根据长江口和杭州湾的环境容量,结合排放口的稀释扩散能力,合理确定污水排放方案。  相似文献   

5.
大亚湾北部沿岸污水排海位置优化选择的研究   总被引:2,自引:0,他引:2  
阐述了大亚湾北部沿岸污水排海位置优选的方法。根据研究海区的水深条件,海岸地形特点,欧拉余流流场,海流流速,渔业水产,旅游等资源的分布特征和水质条件等,定性地确定6个预选排污海区。然后利用Roberts的近区初始稀释模型和二维水质模型,以南海石油化工项目的污水排海为例,定量地计算被确定的六个预选排污海区的稀释扩散输移能力。通过比较,认为大亚湾北部沿岸的污水不适宜就近排入靠岸海域。当污水量不大时,排污  相似文献   

6.
基于Mike21模型,建立了莱州湾附近海域的水动力计算模型,在对潍坊海化工业园区拟建排污口海域水动力计算结果验证正确的基础上,将水动力模型耦合物质输运模型,对工业园区拟建排污口排放污染物质的输移扩散进行数值模拟研究,研究结果显示:污水排海点拟建位置附近海域的水动力交换能力较差,在拟建污水排海点排放污水时,排放污染物的输移扩散造成较大面积的超标水域,影响的二类及三类海水水质功能区的最大面积分别为4.11km~2和2.36km~2,并影响附近3.07km~2水域底播养殖区。  相似文献   

7.
为科学选择海水淡化浓盐水排海方案,运用MIKE3数值模拟软件,选取福建晋江附近海域,建立了海水淡化浓盐水排海三维数值模型,模型水位振幅误差在10 cm以内,流速、流向计算结果与实测值变化规律一致,精度符合要求。考虑多端口、排放口间距、喷射速度等因素对浓盐水稀释的影响,选取了4种不同的浓盐水排放方案,开展了海水淡化浓盐水排放扩散模拟,计算了不同排海方案下盐升包络面积。结果表明,晋江海域浓盐水排放量为3.5万t/d的海水淡化工程采用扩散器后盐升分布面积显著减少,采用多个排放口且每个排放口多个端口喷射的排放方案,可明显增强浓盐水在受纳海域中的扩散稀释效果,盐升3的分布面积可减少近一半。建议加强我国海水淡化工程浓盐水排海扩散器的研究与应用,保护受纳海域海洋生态环境。  相似文献   

8.
南通污水排海工程排放点比选的数值模拟   总被引:3,自引:0,他引:3  
采用数值模拟的方法,计算和分析了南通污水排海工程排放点位于-4m、-7m和-9m三个水深位置的污染物扩散影响,结果表明,在海域水动力条件下,-4m点高质量浓度COD水体面积最大,排放口污染最重,又位于浅海区,对海洋养殖极为不利,不宜选择;-7m点排放口和-9m点排放口均没有出现超过三类水质标准的区域,-7m点排放口影响水域COD质量浓度大部分为二类水质标准区域,只有面积很小甚至可以忽略不计的小范围三类水质标准区域,满足排海要求;-9m点排放口虽然对海域影响最小,但因其离岸距离过远,将大幅增加工程的施工及运营难度,为此,在能够保障COD排海条件的情况下,同时结合各方案管线长度带来的施工难度以及造价费用,采取-7m点为最佳排海口方案。  相似文献   

9.
阐述了大亚湾北部沿岸污水排海位置优选的方法。根据研究海区的水深条件、海岸地形特点、欧拉余流流场、海流流速、渔业水产、旅游等资源的分布特征和水质条件等,定性地确定6个预选排污海区。然后利用Roberts的近区初始稀释模型和二维水质模型,以南海石油化工项目的污水排海为例,定量地计算被确定的六个预选排污海区的稀释扩散输移能力。通过比较,认为大亚湾北部沿岸的污水不适宜就近排入靠岸海域。当污水量不大时,排污位置选在距马鞭洲岛南端以东约4km处(即C海区),可达到环境、经济、社会三大效益协调统一的效果。但当污水量较大,排海污染物量大时,排污海域的位置应选择在赤洲岛与黄毛山岛之间,即E海区.或在C海区与E海区之间。  相似文献   

10.
本文采用 ADI 方法模拟了海西湾的潮流、水位场和 COD 扩散运动,所得结果与观测值符合较好。计算结果表明:海西湾自净稀释能力良好;扩建后的薛家岛码头,若以0.5t/d 的 COD 负荷量排放,整个海湾水均属一类水质;如果以二类水质标准来评价距离码头500m 以外的海域,薛家岛码头的最大 COD 负荷量可达2.3t/d.  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
双壳贝类血淋巴中儿茶酚胺的检测方法初步研究   总被引:1,自引:0,他引:1  
研究的目的是探索一种检测双壳贝类血淋巴中儿茶酚胺含量的方法。以栉孔扇贝(Chlamysfarreri)和长牡蛎(Crassostreagigas)为实验对象,研究了取样、抗氧化剂、氧化铝用量以及Tris缓冲液用量等对实验结果的影响。结果表明,高效液相色谱电化学检测器法(HPLC-ECD)可以灵敏高效地对双壳贝类血淋巴中儿茶酚胺进行定性、定量检测。实验表明,取样时间最长不超过1.5min;还原性谷胱甘肽作抗氧化剂效果较好;前处理各试剂与血样量的最适配比为血样量1.5mL,Tris缓冲液(1.5mol/L,pH8.6)1mL和氧化铝25mg;水洗后离心并尽可能吸干氧化铝中的水分。去甲肾上腺素、肾上腺素和多巴胺的回收率分别为53%~69%、47%~73%和48%~56%。  相似文献   

15.
为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明:黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。  相似文献   

16.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

17.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

18.
The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared.  相似文献   

19.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

20.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

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