INITIAL SEDIMENTATION OF WASTE PARTICLES DISCHARGED IN COASTAL WATERS     

王发君 《中国海洋湖沼学报》1992,10(1):84-91

Based on a puff model . and together with the consideration of convection , dispersion and descent of suspended waste particles in marine environment , a numerical model is presented to predict the initial sedimentation of waste particles discharged from ocean outfalls in coastal waters and to compute the stable sedimentation rate in homogeneous trde current fields with water depth constant . When the time step selected is small enough , the results from this model agree well with that from the semi-analytical solution , and have sufficient precision for evaluating the impact on the environment caused by sedimentation of waste particles discharged from ocean outfalls. A numerical example is given for predicting the sedimentation of waste particles discharged in Heishijiao , Dalian .  相似文献   

地下洞库勘察中的深斜孔钻探和压水试验技术          下载免费PDF全文

吉孟瑞  孙桂明  吴昌庆  原华山 《山东国土资源》2001,17(2):56-60

青岛市黄岛区拟建设海底地下油气储藏库,前期地质勘察工作要求施工倾角45°、深220m的取心钻孔4个,并在孔内分段进行压水试验.本文介绍了如何利用XY-4型金刚石小口径钻机施工基岩深斜孔及压水试验技术.  相似文献   

Prediction of lateral variability in fracture intensity using multicomponent shear-wave surface seismic as a precursor to horizontal drilling in the Austin Chalk   总被引：1，自引：0，他引：1  

Michael C. Mueller 《Geophysical Journal International》1991,107(3):409-415

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Optimization of grid-drilling using computer simulation     

J. William Miller Jr. 《Mathematical Geology》1991,23(2):201-218

A computer simulation method has been developed to find efficient drilling grids for mineral deposits. A well-known ore deposit is used as a model to develop an efficient pattern for undiscovered ore bodies in the same area or in other prospects where similar geometry is suspected. The model for this study is the Austinville, Virginia deposit, a Mississippi Valley-type deposit composed of 17 ore bodies totaling 34 million short tons (30 million metric tons). The method employs a computer program that simulates drilling the model deposit with different patterns, including various levels of follow-up drilling. Follow-up holes are drilled in fences at one half the original spacing around holes in the grid that show ore-grade mineralization. Each pattern is drilled 100 times from random starting locations to provide a range of outcomes of drilling, including the best, worst, and most likely. For this study, patterns of 100 drill holes were composed of 10 fences spaced 1000–5000 feet (305–1524 m) apart, each with 10 holes spaced 200–1000 feet (61–305 m) apart. In all, 25 grids were used with zero to three levels of follow-up drilling. The 600/2000 grid, with drill holes spaced 600 feet (183 m) apart in fences spaced 2000 feet (610 m) apart, was compared with the 200/5000 grid because they represented contrasting outcomes. The 600/2000 grid penetrated many ore bodies consistently but with few multiple hits to individual ore bodies; whereas the 200/5000 grid inconsistently penetrated few ore bodies with many multiple hits. The 600/2000 grid was more efficient than the 200/5000 grid at hitting large ore bodies of 1,000,000 short tons or greater (900,000 metric tons or greater) and was made more effective by adding one cycle of follow-up drilling. The 600/2000 grid had a 97% chance of hitting one or more large ore bodies with at least one drill hole per ore body, and the 200/5000 grid had a 64% chance. Once hit, there was an 82% chance that the largest ore body would be penetrated by three or more holes when using the 600/2000 grid and an 88% chance using the 200/5000 grid.  相似文献   

中国海洋倾废历史与管理现状     

张和庆 《广东海洋大学学报》2003,23(5):15-23

介绍了我国海洋倾废的历史、发展过程和管理现状 ,分析了海洋倾倒的现状和面临的困难。文章还提出通过高新技术把疏浚泥迅速转化为再生资源进行利用和污染土无害化处理技术 ,从根本上减少疏浚泥海洋倾倒的数量和缓减海洋倾倒区紧张的状况 ,减少对海洋环境的污染  相似文献   

Problems of soil and groundwater pollution in the disposal of “marble” slurries in NW Sicily     

G. Rizzo  F. D’Agostino  L. Ercoli 《Environmental Geology》2008,55(5):929-935

This work deals with disposal of slurries generated during the cutting and polishing processes of slabs of decorative sedimentary carbonate rocks in the north western Sicily. At present, they are used as fillers of dismantled quarries near the sawmills and, as a final step of reclamation, are covered with earth layers. In spite of such inexpensive solution, there is lack of knowledge about the composition of the waste. In order to assess if there is any threat for the environment and to suggest indications for alternative solutions, such as recycling or inactivation processes, the slurries were analysed by XR diffraction, simultaneous thermal analysis, ICP/MS, ionic chromatography, FTIR, UV-Vis, COD and TOC measurements, grain size analysis. Results indicate that the slurries can threaten the groundwater, because of the high chemical oxygen demand; furthermore they can modify the mechanism of groundwater recharge, because of their grain size distribution. Some laboratory tests show that, even in very aggressive conditions, the solid pollutants persist in the waste and slowly release into water the products of their degradation. The slurry therefore should be subjected to inactivation treatment before disposal or, alternatively, recycled as secondary raw material for a suitable process.  相似文献   

Anthropogenic influence on trace element geochemistry of healing mud (peloid) from Makirina Cove (Croatia)     

S. Miko  G. Koch  S. Mesić  M. Šparica-Miko  M. Šparica  R. Čepelak  A. Bačani  P. Vreča  T. Dolenec  S. Bergant 《Environmental Geology》2008,55(3):517-537

Due to their balneotherapeutic features, the organic-rich sediments in Makirina Cove are an important source of healing mud. An environmental geochemistry approach using normalization techniques was applied to evaluate the anthropogenic contribution of trace metals to sediments used as healing mud. Sediment geochemistry was found to be associated with land-use change and storm events, as well as with proximity of a road with heavy traffic in the summer months. Local valley topography preferentially channels lithogenic and pollutant transport to the cove. Concentrations and distribution of trace metals indicate lithogenic (Ni, Cr, Co) and anthropogenic (Pb, Cu, Zn and Se) contributions to the sediments. The calculation of enrichment factors indicates a moderate (EFs between 2–3.5) input of anthropogenic Cu and Pb in surficial sediments to a depth of 10 cm. Patients using the Makirina Cove sediments as healing mud could be to some extent exposed to enhanced uptake of metals from anthropogenic sources via dermal contact.  相似文献   

Experimental study on the deterioration and natural remediation of the Ariake Sea tidal mud caused by the sea laver treatment acid practice and the upward seepage of pore water liquid     

Yan-Jun Du  Song-Yu Liu  Shigenori Hayashi 《Environmental Geology》2008,55(4):889-900

This study presents a laboratory study of the following two aspects: (1) the influence of sea laver treatment acid on the geoenvironmental properties of Ariake Sea tidal mud, and (2) the natural remediation effect on the sea laver treatment acid contaminated Ariake Sea tidal mud caused by the upward seepage of pore water liquid in the mud. Firstly, the mechanisms of the transport of sea laver treatment acid in the Ariake Sea tidal mud and the generation mechanisms of the upward seepage flow in the Ariake Sea tidal mud are discussed. Secondly, a series of one-dimensional laboratory infiltration tests were carried out to investigate the deterioration of the Ariake Sea tidal mud caused by the sea laver acid treatment practice. Test results reveal that the acid treatment practice caused considerable change in the geochemical properties of the mud in terms of increase in sulfide content and decrease in pH value. After the treatment by the sea laver treatment acid, the sulfide content of the mud even exceeded the safe limit value for the benthos, which represents undesirable living condition for benthos. Thirdly, series of laboratory fresh seawater infiltration tests for the deteriorated Iida site mud were conducted to illustrate this natural remediation efficiency. It is found that with the infiltration of the fresh seawater, the sulfide content of the Iida site mud was considerably reduced and pH value increased to an acceptable range for benthos living in the tidal flat mud. With the increase in the infiltration time and the hydraulic gradient, the remediation efficiency could be increased.  相似文献   

Effects of natural attenuation processes on groundwater contamination caused by abandoned waste sites in Berlin     

Helmut Kerndorff  Stephan Kühn  Thomas Minden  Dagmar Orlikowski  Thomas Struppe 《Environmental Geology》2008,55(2):291-301

The aim of this research project is to identify, characterize and quantify natural attenuation (NA) processes in groundwater affected by emissions of abandoned waste disposal sites in Berlin-Kladow/Gatow, Germany. It is part of the funding priority called KORA established by the Federal Ministry for Education and Research (BMBF) to explore the extent to which NA can be used for remedial purposes for varied forms of soil and groundwater contamination. Information on the emission behaviour of individual parameters is generated on the basis of hydrogeochemical comparison of 20 years old and new data. Using groundwater-modelling and CFC-analysis, information on the transport and retention of pollutants in groundwater is compiled. The microbial colonization of contaminated aquifers is characterized by molecular biological methods [polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE)] to differentiate between contaminated and not contaminated zones.  相似文献   

Shear strength characterization of municipal solid waste at the Suzhou landfill, China   总被引：5，自引：0，他引：5  

Tony L.T. Zhan  Y.M. Chen  W.A. Ling 《Engineering Geology》2008,97(3-4):97-111

The current practice of slope stability analysis for a municipal solid waste (MSW) landfill usually overlooks the dependence of waste properties on the fill age or embedment depth. Changes in shear strength of MSW as a function of fill age were investigated by performing field and laboratory studies on the Suzhou landfill in China. The field study included sampling from five boreholes advanced to the bottom of the landfill, cone penetration tests and monitoring of pore fluid pressures. Twenty-six borehole samples representative of different fill ages (0 to 13 years) were used to perform drained triaxial compression tests. The field and laboratory study showed that the waste body in the landfill can be sub-divided into several strata corresponding to different ranges of fill age. Each of the waste strata has individual composition and shear strength characteristics. The triaxial test results showed that the MSW samples exhibited a strain-hardening and contractive behavior. As the fill age of the waste increased from 1.7 years to 11 years, the cohesion mobilized at a strain level of 10% was found to decrease from 23.3 kPa to 0 kPa, and the mobilized friction angle at the same strain level increasing from 9.9° to 26°. For a confinement stress level greater than 50 kPa, the shear strength of the recently-placed MSW seemed to be lower than that of the older MSW. This behavior was consistent with the cone penetration test results. The field measurement of pore pressures revealed a perched leachate mound above an intermediate cover of soils and a substantial leachate mound near the bottom of the landfill. The measurements of shear strength properties and pore pressures were utilized to assess the slope stability of the Suzhou landfill.  相似文献