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Combined Water-Oxygen Pinch Analysis with Mathematical Programming for Wastewater Treatment
Water-oxygen pinch analysis is an effective method to decrease the wastewater quantity and improve the wastewater quality. But when multiple-contaminants are present, the method is difficult to be carried out. In this paper, the method that combines water-oxygen pinch analysis with mathematical programming is proposed. It obtains the general optimal solution and leads to the reuse stream that cannot be found only by pinch analysis. The new method is illustrated by an example, and the annual cost is reduced by 8.43% compared with the solution of literature....
2020-07-08 21:52:19浏览：48
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A method of automatic image segmentation for gas bubbles in water
This paper presents an algorithm of automatic bubble image segmentation using the improved ant colony optimization methodology.The ant colony optimization method is a metaheuristic algorithm,and has been applied in many fields.To reveal the versatility and appropriateness of automatic bubble image segmentation,the fuzzy clustering analysis method is employed in ant colony optimization algorithm.Compared with the wellknown image feature extraction operators such as SUSAN and Canny,the proposed method can comparatively suitable to extract the gas bubbles image edge features.The experimental results show that the proposed method is effective and reliable,and can achieve satisfactory image edge extraction effect....
2020-07-08 21:52:19浏览：33
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Sensitivity analysis of dimensionless parameters for physical simulation of water-flooding reservoir
A numerical approach to optimize dimensionless parameters of water-flooding porous media flows is proposed based on the analysis of the sensitivity factor defined as the variation ration of a target function with respect to the variation of dimensionless parameters. A complete set of scaling criteria for water-flooding reservoir of five-spot well pattern case is derived from the 3-D governing equations, involving the gravitational force,the capillary force and the compressibility of water, oil and rock. By using this approach,we have estimated the influences of each dimensionless parameter on experimental results, and thus sorting out the dominant ones with larger sensitivity factors ranging from 10-4 to 100....
2020-07-08 21:52:19浏览：44
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Application of Element-Free Method to water quality analysis of Miyun reservoir
This paper presents a 3D mathematical model for transfer and transform of water contaminants in reservoir, describes the discrete methods and the compute process of using an element-free collocation method. By these models and methods, the water quality conditions of Miyun reservoir area, the quantified description of three dimensions concerning the distribution and change of diversified contaminants are obtained within the assigned time. The distributions of total nitrogen and total phosphorus of the reservoir area in 2003, 2004 and 2005 are simulated and forecasted by the boundary conditions in 2003, so the main development trend is shown. It is found through calculation that: The contribution of the bed mud with regard to total phosphorus is comparatively marked. On the whole, the influence factor of the bed mud in the reservoir area and other comprehensive factors to total phosphorus are quite great. The influence of the living things or other function in the surface water of the Chaohe River valley in the east of the reservoir on the total phosphorus is comparatively conspicuous. Within the reservoir area in spring, summer and autumn, the concentration distribution of total nitrogen is basically in the trend of a slow progressive decrease, but the concentration of total phosphorus increases progressively. It is just contrary in autumn, winter and spring, the concentration of total nitrogen increases and the concentration of total phosphorus decreases. On the whole of the year's development, the total nitrogen is basically in a steady state, and the total phosphorus is in the increasing trend with years, but the kind of the trend is not conspicuous....
2020-07-08 21:52:19浏览：46
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Environmental Characteristics of Groundwater: an Application of PCA to Water Chemistry Analysis in Y
For our investigation into the water quality in Yulin city, we collected 76 typical water samples to be tested for particle quality. By applying a Romani type classification method the groundwater of Yulin city was classified into nine categories by type, i.e., Ca-HCO3, Na-HCO3, Na-HCO3-SO4-Cl, Na-HCO3-SO4, Na-Cl, Na-Cl-HCO3, Na-CaHCO3, Ca-Cl-HCO3 and Ca-HCO3-SO4-Cl. A principal component analysis was carried out in order to analyze the groundwater environment. From this analysis we considered that the information collected could be represented by 21 indices from which we extracted seven principal components, which, respectively, accounted for 37.4%, 13.0%, 8.1%,7.2%, 6.3%, 5.9% and 4.6% of the total variation. The results show that the groundwater environment of this region is largely determined by characteristic components of the natural groundwater background. One part of the water was polluted by leaching/eluviation of solid waste generated from coal mining. Another part of the ground water was contaminated by acid mine water from the coal layer and from improper irrigation. In addition, geological and hydrogeological conditions also cause changes in the water environment....
2020-07-08 08:49:41浏览：60
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Combinatorial analysis on spatial information statistics for the karst water environment in Guiyang,
The karst groundwater system is extremely vulnerable and easily contaminated by human activities.To understand the spatial distribution of contaminants in the groundwater of karst urban areas and contributors to the contamination,this paper employs the spatial information statistics analysis theory and method to analyze the karst groundwater environment in Guiyang City,Based on the karst groundwater quality data detected in 61 detection points of the research area in the last three years,we made Kriging evaluation isoline map with some ions in the karst groundwater,such as SO42,Fe3+,Mn2+ and F,analyzed and evaluated the spatial distribution,extension and variation of four types of ions on the basis of this isoline map.The results of the analysis show that the anomaly areas of SO42-,Fe3+,Mn2+,F and other ions are mainly located in Baba'ao,Mawangmiao and Sanqiao in northwestern Guiyang City as well as in its downtown area by reasons of the original non-point source pollution and the contamination caused by human activities (industrial and domestic pollution)....
2020-07-08 08:49:41浏览：37
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Integrated Water and CGE Model of the Impacts of Water Policy on the Beijing's Economy and Outp
The article used general equilibrium model to analyze the change of gross domestic product and industry output affected by water resources policies in Beijing City by using GEMPACK soft tool.The article researches on rules of water supply and demand,evaluating water resources,building water resources input and output table,establishing water computable general equilibrium model and stimulating water policy.The stimulation gives a scenario that increases water price by 10%.The result shows the following aspects.First,water resources policy infects gross domestic product and industry output in different ways.There are different behaviors in different industries as to the water policy.Agriculture industry has the same tendency as water price change and it has more sensitive to water quantity than to water price.For basic energy industries such as oil and chemistry and gas,they show diversity tendency.As to some high water consumer industry such as paper and textile etc.,water resource economic policy can infect them greatly and can promote them to accomplish more water-saving technology.Waste water and construction and service industries show the same tendency as to water policy.Second,government should pay more attention to water resource policy by macro economic administration.The simulation also shows that the output and supply and consumer price change more than expect as to water policy in a free market economic in water industry.So as to a government policy maker,one should be more carefully and prepare suitable forecast and plan to water policy and its negative impact....
2020-07-08 08:49:41浏览：45
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Flow and cavitation characteristics of water hydraulic poppet valves
Two types of poppet valves were tested, one is a poppet with a sharp-edged seats, and the other is that with a chamfered seat. During the tests, the effects of backpressure and poppet lift on flow characteristics were considered. Cavitation inception was detected by the appearance and rapid growth of a particular low frequency component of the outlet pressure fluctuation of valve when cavitation occurs. Experimental results show cavitation, back pressure, valve opening and its geometrical shape have significant effects on the flow characteristics of valve. The flow coefficient of throttle with water used as working medium is 0. 85～0. 95 when there is no cavitation. The pressure drop of flow saturation decreases with the increasing of poppet lift. The sharp-edged throttle has stronger anti-cavitation ability than the chamfered one....
2020-07-08 08:49:41浏览：59
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Seismic Reliability and Rehabilitation Decision of Water Distribution System
In order to evaluate the seismic reliability of water distribution system and make rehabilitation decisions correspondingly, it is necessary to assess pipelines damage states and conduct functional analysis based on pipe leak-age model. When an earthquake occurred, the water distribution system kept serving with leakage. By adding a virtual node at the centre of the pipeline with leakage, an efficient approach to pressure-driven analysis was developed for simulating a variety of low relative scenarios, and a hydraulic leakage model was also built to perform hydraulic analy-sis of the water supply network with seismic damage. Then the mean-first-order-second-moment method was used to analyse the seismic serviceability of the water distribution system. According to the assessment analysis, pipes that were destroyed or in heavy leakage were isolated and repaired emergently, which improved the water supply capability of the network and would constitute the basis for enhancing seismic reliability of the system. The proposed approach to seismic reliability and rehabilitation decision analysis on water distribution system is demonstrated effective through a case study....
2020-07-08 08:49:41浏览：53
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The effect of water spreading system on the functionality of rangeland ecosystems
In recent decades,the control of floods is an efficient management practice for the rehabilitation of rangelands in most arid and semiarid areas.To evaluate the benefits,we used the Landscape Function Analysis (LFA) method to assess the function of patches and qualitative capability of a rangeland ecosystem in Gareh Bygone region,Fars province,southwestern Iran.Landscape functionality depends on soil,water and nutrient (collectively called "resources") conservation and use within a given ecosystem.Many landscapes are naturally heterogeneous in terms of resource control and possess patches,where resources tend to accumulate,and inter-patches.Assessing rangeland health and function of landscape patches in response to environment and management can give rise to correct management decisions for qualitative improvement of the ecosystem.Therefore,our study area was divided into two parts,i.e.water spreading and control parts,and sampling was done using LFA method in each part separately.Structural parameters,including the number,length and width of patches,and the mean length of inter-patches,were determined by the method to characterize the functional status of the monitoring sites.For each patch/inter-patch type identified in the transect organization log,we recorded its soil surface properties classified according to the Soil Surface Assessment Method.The density,canopy cover and composition of plants were then assessed.The results showed that the number of ecological patches and their dimensions were significantly increased in the water spreading site.Soil stability and the values of nutrient cycling indices were increased but the infiltration values were decreased in the water spreading site.It could be related to the effect of suspended materials transported by floods to the soils in the study area.The improvement of ecological patches and rangeland ecosystem was achieved where water spreading systems were practiced.Therefore it can be concluded that water spreading as a management plan plays an important role in arid land ecosystem functionality....
2020-07-08 08:49:41浏览：69
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近似空间的合成及其应用
讨论了粗糙集理论中近似空间的合成及其在智能信息系统中的应用.证明了随着可利用信息的不断增加,上下近似对概念的描述也更精确.从而为粗糙集理论的应用提供了更为广阔的前景....
2020-07-07 22:08:29浏览：55
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HYGAS 气化技术及应用分析
介绍了HYGAS气化技术的工艺流程、技术特点和性能指标等，并对其工业应用领域进行分析。分析表明，其煤种适应性宽，碳转化效率高，物耗能耗低，较适用于以煤制合成气和IGCC的方式，可对包括褐煤在内的低阶煤进行处理利用。...
2020-06-12 16:20:36浏览：1447
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GC/MS Analysis of Organic Compounds in Hot Water-Extractable Fraction from Shenfu Coal
Shenfu Coal was extracted with hot pure water and slurry was isolated. The concentrated benzene-soluble fraction (CBSF) was analyzed with GC/MS and four types of organic compounds (OCs) were detected: HACOCs, DTEs, DMDT and LCAs. The amount of benzyl benzoate which is the most abundant OC was calculated by an internal standard method with an indicated amount of BP. The broken hydrogen bonds and ether bonds were responsible for the extraction of OCs from the coal .DTEs, DMDT and LCAs are essentially insoluble in water, whereas they are soluble, probably owing to intermolecular interaction of OCs with HACOCs....
2020-06-12 16:19:44浏览：1425
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Solid superacid-catalyzed hydroconversion of an extraction residue from Lingwu bituminous coal
A solid superacid was prepared as a catalyst.The catalyst was characterized by ammonia temperatureprogrammed desorption,surface property measurement,and analyses with scanning electron microscopy and Fourier transform infrared spectrometry.A extraction residue from Lingwu subbituminous coal was subject to non-catalytic and catalytic hydroconversion using cyclohexane as the solvent under pressurized hydrogen at 300 ℃ for 3h.The results show that the total yield of petroleum ether-extractable arenes from catalytic hydroconversion is much higher than that from non-catalytic hydroconversion.The cleavage of Car-Calk bonds in the residue could significantly proceed during catalytic hydroconversion....
2020-06-12 16:19:17浏览：1431
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An analytic solution describing the visco-elastic deformation of coal pillars in room and pillar min
Coal pillar deformation is typically nonlinear and time-dependent.The accurate prediction of this deformation has a vital importance for the successful implementation of mining techniques.These methods have proven very important as a way to excavate coal resources from under buildings,railways,or water bodies.Elastic and visco-elastic theory are employed with a Maxwell model to formulate an analytic solution for displacement of coal pillars in room and pillar mine.These results show that the visco-elastic solution adequately predicts the coal pillar deformation over time.We conclude that the visco-elastic solution can predict the coal pillar and roadway displacement from the measured geological parameters of the conditions in situ.Furthermore,this method would be useful for mine design,coal pillar support optimization,ground subsidence prediction,and coal pillar stability analysis....
2020-06-12 16:18:52浏览：1437
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