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1.
朱小宁 《中国煤田地质》2002,14(1):48-49,54
根据生产实践总结,对窑街三矿矿井危害最大的是位于煤二层上部的第四系砾石层潜水,其次是烧变岩孔隙水与地表塌陷区积水,经多年水文地质资料分析,认为砾石层与地表水大通河水力联系密切,如采用帷幕注浆,打放水孔或泄水巷都不会取得好的效果,切断大通河与砾石层的水力联系,是根治砾石层最有效的方法,故要在充分研究大通河补给范围的情况下有目的地修筑拦河提与地下挡水墙,烧变岩孔隙水已利用打泄水巷,放水孔的方式排完,目前主要是严防地表水重新灌入,对塌陷区复垦,修筑防洪渠是防止大气降水进入塌陷区及防止地表水溃入矿井的有效途径。  相似文献   

2.
Column leaching tests on black coal mine washery wastes were performed, to determine the chemistry of acid generation. Coal mine coarse rejects and tailings were subjected to wet and dry cycle dissolution and subsequently column leached. The rates of iron sulphide oxidation and carbonate mineral dissolution were determined based on the drainage chemistry. The kinetic data from column leach experiments are used to predict the time required to deplete the acid producing and acid consuming minerals in the mine wastes. The acid production in the mine rejects was found to depend upon iron chemistry, carbonate chemistry, diffusion of oxygen, and permeability. The chemistry of the drainage from two different coal mines is compared.  相似文献   

3.
川西高原砂金矿床形成规律   总被引:1,自引:0,他引:1       下载免费PDF全文
崔克倍 《地质科学》1989,(4):308-313
砂金富集规律可归纳为五条:(1)砂金比重大,体积小,一般下沉于砂砾层底部基岩之上,形成富矿带。(2)河流流速减缓处是砂金富集之场所,如河流内湾处;两河会流处;河谷由宽突变窄处;河谷由窄突变宽处。(3)河床起伏不平是砂金富集之主要条件。最理想的河床是软硬相间之岩层,如砂页岩互层,且走向横穿河谷,倾斜较陡,这样,便形成具有无数隔梁与隔槽的起伏不平的河床,砂金受阻,易于停积。(4)位于谷旁之古老河床沉积阶地是无水患的易采砂金矿床,不容忽视。(5)红黄杂色铁砂及石英碎屑常为砂金富集标志。  相似文献   

4.
砾钢渣抗液化特性试验研究   总被引:1,自引:0,他引:1  
陈化的钢渣作为土工回填材料是废弃钢渣循环利用的主要途径之一。按土的工程分类方法,将废弃钢渣划分为砾钢渣、粗钢渣和细钢渣。针对砾钢渣,考虑固结应力比、振动频率、围压和含砾量等影响因素开展动三轴试验研究。分析了砾钢渣的应力、应变和动孔隙水压力的特性,分析了砾钢渣试样的动强度与振动次数、动应变与振动次数、孔隙水压力与振动次数和动应力与动应变关系。采用Seed和Finn提出的饱和砂土动孔压计算模型分析砾钢渣的动孔压曲线类型,并与传统砂砾土的抗液化强度进行比较。得出砾钢渣的抗液化特性较好,工程中可以用砾钢渣替代传统的砂土、砂砾土、砂砾料和砂卵石作为回填料,解决砂砾资源日渐短缺的问题。  相似文献   

5.
The extraction of mineral resources requires access through underground workings, or open pit operations, or through drillholes for solution mining. Additionally, mineral processing can generate large quantities of waste, including mill tailings, waste rock and refinery wastes, heap leach pads, and slag. Thus, through mining and mineral processing activities, large surface areas of sulfide minerals can be exposed to oxygen, water, and microbes, resulting in accelerated oxidation of sulfide and other minerals and the potential for the generation of low-quality drainage. The oxidation of sulfide minerals in mine wastes is accelerated by microbial catalysis of the oxidation of aqueous ferrous iron and sulfide. These reactions, particularly when combined with evaporation, can lead to extremely acidic drainage and very high concentrations of dissolved constituents. Although acid mine drainage is the most prevalent and damaging environmental concern associated with mining activities, generation of saline, basic and neutral drainage containing elevated concentrations of dissolved metals, non-metals, and metalloids has recently been recognized as a potential environmental concern. Acid neutralization reactions through the dissolution of carbonate, hydroxide, and silicate minerals and formation of secondary aluminum and ferric hydroxide phases can moderate the effects of acid generation and enhance the formation of secondary hydrated iron and aluminum minerals which may lessen the concentration of dissolved metals. Numerical models provide powerful tools for assessing impacts of these reactions on water quality.  相似文献   

6.
Acid mine drainage (AMD) is treated at several points in the Lausitz lignite mine district (Saxony, Germany) in treatment plants. The remaining alkaline low density sludge (LDS) was deposited in acidic mining lakes without having an impact on the lake water quality. Batch experiments show that alkalinity can be raised using LDS from acid mine drainage treatment plants together with CO2. Batch experiments were conducted using lake water and deposited LDS from the mining lake Spreetal-Nordost with varying concentrations of CO2. Also the duration of gas contact as well as the LDS–water ratio was changed in the batch experiments. The gas contact time and the partial pressure of CO2 are the relevant parameters controlling the alkalinity in the lake water at the end of the experiments. The Ca and Mg concentrations of the pore water are relevant for higher pH values. Therefore, dissolved CO2 can form bicarbonate or carbonate complexes, thus alkalinity rises. A second factor for alkalinity gain is the calcite content of the sludge, because CO2 triggers the dissolution of carbonates. Therefore, unused calcite in the sludge can raise the alkalinity more effectively by the application of carbon dioxide. Furthermore, it was shown that remobilization of trace elements will not affect the water quality.  相似文献   

7.
云南三江一河典型地区河谷第四系发育特征   总被引:6,自引:1,他引:6  
程捷  罗绍峰 《现代地质》1994,8(1):11-19
三江一河(金沙江、怒江、澜沧江、红河是流经云南境内的4条主体水系,将上述4条河流河谷第四系的野外观察加以总结得出;金沙江河谷局部发育早一中更新世的湖相层和河湖相层,常形成晚期阶地的基座,晚更新世至全新世冲积层构成四级阶地;怒江河谷第四系发育较差,在六库的上游河谷中冲积层极不发育,只有局部地方有少量的河漫滩砂砾层(全新世),在六库至过街河段中,尤其是过街盆地,发育有中更新世至全新世的冲积层和洪积层,前者构成五级阶地,后者形成巨大的洪积扇分布在河流右岸的谷底或苍坡上;澜沧江除景洪、勐罕(橄榄坝)盆地外,其它河段主要为峡谷,第四系很少,在景洪盆地中发育有第二、第一级阶地和河漫滩冲积层;红河的第四系有中更新世至全新世的冲积层,并构成五级阶地。基于上述第四系特点,简要地讨论了这4条河流的形成时代。  相似文献   

8.
Surface water samples were collected from Langtang Lirung glacier outlet point to the Narayani river system in central Nepal in order to investigate the role of elevation in the variation of chemistry along the drainage networks. The chemistry of Langtang–Narayani river system was dominated by sulfide oxidation coupled with carbonate dissolution and weathering of silicate minerals. Calcium and magnesium concentrations were relatively higher than other cations and the sum of both species strongly correlated with alkalinity, supporting the dissolution of carbonate and dolomite as the dominant source for these ions. Aluminosilicate minerals primarily as albite and anorthite appeared as dominant silicate minerals within the drainage basin. Bisiallitization was the dominant type of weathering within the entire drainage system. Hydrogen ion concentration was lower in the low elevation sites than in high elevation sites reflecting the more consumption of carbon dioxide in the low elevation sites due to enhanced chemical weathering rates. Furthermore, major solutes like sum of base cations, silicon as well as alkalinity increased in concentration in the lower elevation sites. All regulating factors appeared to be directly related to elevation and hence elevation appeared to be the prime factor for the variation in chemical species along the Langtang–Narayani river system. Toshiyuki Masuzawa: deceased.  相似文献   

9.
李燚  韦正彬  施洪明 《云南地质》2011,30(3):362-365
石槽河煤矿位于断陷盆地中,可采煤层M3位于最低排泄基准面之下,无法自流排水,矿坑水主要来自煤层顶板、河水渗流及降水渗入。计算获得矿井漏水量为4472m3/d(正常)和6411m3/d雨季。  相似文献   

10.
One of the most famous blue sapphire deposits in Thailand and SE Asia is from the Bo Phloi District, Kanchanaburi Province, Western Thailand. This paper presents the results of our gemstone investigation as well as establishing the Bo Phloi depositional sequence as one of the Quaternary Type Sections in the region. Relationships among the sedimentology, depositional sequences and geomorphology were investigated in order to understand the gemstone depositional features. Sedimentary structures and textures of the sequences show that the deposition of gemstones is related genetically to fluvial processes. Gemstones are recognized in floodplain and low terrace deposits where gemstone paystreaks concentrate mostly inside layers of gravel beds and foreset-bedded gravels lithofacies. C-14 dating of wood and peat within gemstone-bearing layers indicated that the deposit formed during the middle to late Pleistocene. The gemstone-bearing gravel bed defines a north–south trend along the incised palaeo-channel of an ancient braided river system in the middle part of the basin.  相似文献   

11.
在中国北部边疆西起天山东端的北山,东至大兴安岭北段的4200km地域内,气候干旱少雨,水资源贫乏,第四系地下水是主要供水源之一。本文首次比较系统地研究了该区第四纪堆积物的分布和地下水的赋存规律。文中依据不同地貌单元、地层岩性及气候条件诸因素将本区第四系地下水划分为枝状沟谷砂砾石层孔隙水、河谷冲积平原砂砾石层孔隙水两种主要类型,并着重对有重要供水意义的河谷冲积平原砂砾石层孔隙水的分布、埋藏条件、富水性及水化学特征进行了论述。  相似文献   

12.
普阳煤矿位于一断陷盆地的浅部新近系地层中,矿区被3种类型的水文地质边界圈闭.煤层分布标高低于暗河出口100~230 m,煤田四周及盆地基底均为岩溶含水层,其承压水头高于煤层底板67~268 m,预计最低开采标高的平均承压水头约206 m.为解决矿区地下水突水威胁,监测普阳河水流入和流出的水量,根据水均衡原理及矿坑充水要...  相似文献   

13.
滇西沘江流域水体中重金属元素的地球化学特征   总被引:6,自引:1,他引:5  
通过测定流经兰坪金顸铅锌矿区的沘江水体中Pb、Zn、Cd、As的含量和底泥中重金属元素的化学形态的含量,分析了重金属元素的分布和化学形态的变化。结果表明,沘江水遭到了Cd污染,底泥已经成为重金属元素的蓄积库,以国家土壤环境质量标准(Ⅲ级)衡量,Pb、Zn、Cd和舡分别超标3.4倍、15.8倍、106倍和2.6倍。沘江水中重金属元素含量的峰值在矿山附近的下游,而底泥中重金属元素的峰值在矿山下游30-50km的地方,矿业活动、水流变缓、pH等水体环境条件的变化都能影响水和底泥中重金属元素的含量。底泥中的Pb以碳酸盐结合态为主,Zn和Cd以铁锰氧化物结合态为主,而As以残渣态为主。Pb、Cd、Zn三种元素的环境有效态含量比较高,对沘江流域生态环境具有潜在的巨大的危害。  相似文献   

14.
长江中游阳逻砾石层沉积环境分析   总被引:1,自引:0,他引:1       下载免费PDF全文
本文在野外调查的基础上,选择典型剖面,通过剖面沉积学、岩相划分和粒度分析研究,对长江中游“阳逻砾石层”沉积环境进行了讨论。研究表明,阳逻砾石层的岩性主要砾石层夹砂层,由Gm,Sh和Sp沉积相类型组成;   大多数频率曲线图形态为双峰,且以不对称曲线为主;   概率累积曲线大都为上三段式,以滚动总体为主,约占50%~60%,斜率较大,在35°~45°;   悬浮总体约占20%~30%,斜率在 40°以上;   跳跃总体约占20%~30%,斜率较小,多在 10°~20°。跳跃总体和滚动总体之间均存在有混合带,分选性较差。综合分析认为,阳逻砾石层沉积环境为具有辫状河特点的河流沉积。根据电子自旋共振测年(ESR)得到阳逻砾石层的形成年龄为1.12~1.56MaB.P.,表明阳逻砾石层形成于第四纪早更新世。
  相似文献   

15.
Passive treatment systems are widely used for remediation of acid mine drainage (AMD), but existing designs are prone to clogging or loss of reactivity due to Al- and Fe-precipitates when treating water with high Al and heavy metal concentrations. Dispersed alkaline substrate (DAS) mixed from a fine-grained alkaline reagent (e.g. calcite sand) and a coarse inert matrix (e.g. wood chips) had shown high reactivity and good hydraulic properties in previous laboratory column tests. In the present study, DAS was tested at pilot field scale in the Iberian Pyrite Belt (SW Spain) on metal mine drainage with pH near 3.3, net acidity 1400–1650 mg/L as CaCO3, and mean concentrations of 317 mg/L Fe (95% Fe(II)), 311 mg/L Zn, 74 mg/L Al, 20 mg/L Mn, and 1.5–0.1 mg/L Cu, Co, Ni, Cd, As and Pb. The DAS-tank removed an average of 870 mg/L net acidity as CaCO3 (56% of inflow), 25% Fe, 93% Al, 5% Zn, 95% Cu, 99% As, 98% Pb, and 14% Cd, but no Mn, Ni or Co. Average gross drain pipe alkalinity was 181 mg/L as CaCO3, which increased total Fe removal to 153 mg/L (48%) in subsequent sedimentation ponds. Unfortunately, the tank suffered clogging problems due to the formation of a hardpan of Al-rich precipitates. DAS lifetime could probably be increased by lowering Al-loads.  相似文献   

16.
本文通过对砂金矿床形成过程的分析认为:在地壳局部下沉过程中,砂金在水等强应力作用下,与砾石、砂一起进入沉积盆地,形成砂金的中间储存体;随着地壳的间歇性上升,在蛇曲河流的作用下由于砂金与砾石的运动规律相仿,故和砾面一起被保留在河流冲刷面上的河床滞留砾石沉积中。当地壳多次间歇性上升后,使砂金中间储存体中分散的砂金集中富集在河床滞留砾石层中,从而形成砂金矿床。  相似文献   

17.
郭福生 《沉积学报》2004,22(1):136-141
浙江江山藕塘底组是晚石炭世威宁期陆源碎屑与碳酸盐的混合沉积,包括两种组分在同一岩层内相互混杂形成混积岩和陆源碎屑岩与碳酸盐岩互层形成混积层系。藕塘底组是海陆交互环境的沉积产物,剖面结构具有下细上粗的岸进序列。混积岩形成于滨岸浅滩环境,由沿岸流和回流将河口或滨岸海滩的石英砂带到滨岸浅滩和潮坪相碳酸盐沉积区混杂而成。具两种混积层系类型,即浅海滨岸环境中砂岩与碳酸盐岩互层、河流相碎屑岩与海相碳酸盐岩互层。研究表明,混合沉积成因属“相混合”,主要受区域构造隆升、全球海平面上升和盆地水介质条件特性控制。区域海平面周期性变化和岸进序列可能是华夏古陆强烈隆起的结果。作者还讨论了混合沉积的分类和命名,将陆源碎屑与碳酸盐层相互交替构成的互层和夹层组合称为“混积层系”,并建议将“混积岩”一词用来表征两种组分相互混杂这种特殊沉积事件,而不用作具体岩石名称.  相似文献   

18.
Acid mine drainage is an environmental problem produced when sulphide in mine tailings dams comes in contact with O2, bacteria and water. Oxidation occurs and a succession of reactions is responsible for producing acid and metals in the environment. One solution proposed is to use red mud bauxite (RMB) that is very alkaline to neutralise acidic tailings. Previous experiments showed that RMB has a good neutralisation capacity for a short time, but the long-term neutralisation potential is uncertain. So brine was added to RMB to verify if it can improve long-term alkalinity retention of RMB. Some authors have presented results where seawater or other natural or artificial Ca- and Mg-rich brines were used with RMB to convert the basicity (mainly NaOH) and other soluble alkalinity into low solubility hydroxide, carbonate and hydroxycarbonate minerals. Results showed that neutral pH conditions were maintained over the entire test for RMB and a mixture of RMB with brine. Addition of brine to RMB slightly lowered the pH compared to RMB alone. RMB alone lost a lot of dissolved alkalinity at the beginning of the test. Most of the alkalinity was lost in water after a few flushes for RMB samples. The addition of brine helped to keep neutralisation potential over more cycles of leaching.  相似文献   

19.
The use of scrap-tire-shreds as leachate collection layer in landfills would reduce the magnitude of the current tire disposal problem by converting a waste into a beneficial material. Laboratory studies were conducted to investigate scrap-tire-shreds as an attractive potential alternative to conventional gravel in the drainage layer of leachate collection system by comparative analysis of various physico-chemical parameters. Gravel and scrap-tire-shreds in combination were used as leachate collection layer. Laboratory Test Cells consisting of different combinations of scrap-tire-shreds (size range length = 25.4 mm to 76.1 mm and width = 5 mm) and gravel (size range 10 mm to 20 mm) beds as leachate collection layer with total bed thickness of 500 mm were constructed. Performance study of Test Cells- 1 to 7, having different combinations of scrap-tire-shreds and gravel bed thickness, were studied to work out the best combination. Combined beds of scrap-tire-shreds and gravel gave better results as compared to conventional gravel or scrap- tire- shreds bed when used singly. Test Cell -3 having scrap-tire-shreds layer (200 mm) and gravel layer (300 mm) gave the best results in terms of percentage reduction in various physico-chemical parameters of leachate. The reduction was as high as 68.8 and 79.6% in case of Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) values respectively. Further, three more laboratory Test Cells-8, 9 and 10 were constructed having scrap-tire-shreds and gravel layer ratio same as that of Test Cell- 3 (best combination) but having scrap-tire-shreds of different widths 10 mm, 15 mm and 20 mm to find out the most suitable size. Bed of smaller size scrap-tire-shreds (5 mm) gave better results in comparison to bigger sizes. Leachate sample after passing through combined beds of scrap-tire-shreds and gravel gave better results in percentage reduction in various physico-chemical parameters of leachate as compared to conventional gravel or scrap-tire-shreds bed when used singly.  相似文献   

20.
The paper suggests an accurate approach to studying carbonate equilibrium in the water of the Razdol’naya River. The approach involves measuring pH by Pitzer’s scale, using a cell without liquid junction; measuring the total alkalinity by Bruevich’s technique; and using apparent constants of carbonate equilibrium with regard for the organic alkalinity. The Pitzer technique was employed to calculate the apparent constants of carbonate equilibrium in solution that models the riverine water: Ca(HCO3)2–NaCl–H2O within the range of alkalinity of 0–0.005 mol/kg and temperatures of 0–25°C. Carbonate equilibrium in the water of the Razdol’naya River was sampled for studying at eight sites during all four seasons. Although the contents of biogenic compounds in the water are high, they can merely insignificantly affect the acid–base equilibrium, which is controlled in the riverine water by carbonate equilibrium and the concentrations of humic substances, which play the greater role, the greater the discharge of the river. In addition to the production and destruction of organic matter, carbonate equilibrium in the river is also affected by the supply of humic substances with soil waters and total alkalinity with groundwaters. The fluxes of alkalinity and humic substances annually brought by the Razdol’naya River to Amur Bay are evaluated at 1.33 × 109 mol and 9.9 × 106 kgC, respectively. The carbon dioxide export with the Razdol’naya River is equal to the alkalinity flux and does not depend on the weathering mechanisms.  相似文献   

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