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1.
Abstract:
The water network of a coal mine was audited and simulated by an interactive steady state model and the results were used to optimise the mines water management strategy. Simulation of the interactions showed that calcium carbonate powder could be used as an alternative to lime for neutralization of acid water at a reagent cost saving of 56%. Gypsum crystallization would reduce sulphate concentrations in the neutralization plant by 30% and in the coal processing plant by 60%. The capital cost for a neutralization/gypsum crystallization plant for separate treatment of coal discard leachate and less polluted streams would cost 3.0 million Rand (R), compared to R10.3 million for combined treatment. Only slightly less (8.9 t/d vs. 9.5 t/d) sulphate removal would be achieved during separate treatment. The over-saturation index (OSI) value can be controlled effectively by removing sulphate from the feed water for coal processing. Sulphate has to be lowered to 350 mg/L in a flow of 222 m3/h to obtain an OSI value less than 1. The capital cost of a 222 m3/h biological sulphate removal plant was estimated at R21.8 million (R4.1 million/(ML/d)); the running cost was estimated at R13.7 million/a (R4.10/m3). Pre-washing of the coal would reduce capital and running costs. 相似文献
2.
Abstract. Helicopter-mounted electromagnetic (HEM) surveys have been
used to delimit conductive mine pools and groundwater features
at various areas in the eastern United States that contain
abandoned surface and underground coal mines. HEM was used to
delineate the source areas and flow paths for acidic,
metal-containing groundwater. This will aid remediation efforts.
A recent HEM survey of Kettle Creek Watershed, Clinton County,
Pennsylvania, using a 6-frequency electromagnetic data
acquisition system, is presented. The survey accurately located
conductive pools within underground mines, acidgenerating mine
spoil at surface mines, and areas of groundwater recharge and
discharge. 相似文献
3.
Abstract In many regions of the world, flooded mines are a potentially cost-effective option for heating and cooling using geothermal
heat pump systems. For example, a single coal seam in Pennsylvania, West Virginia, and Ohio contains 5.1 x 1012 L of water. The growing volume of water discharging from this one coal seam totals 380,000 L/min, which could theoretically
heat and cool 20,000 homes. Using the water stored in the mines would conservatively extend this option to an order of magnitude
more sites. Based on current energy prices, geothermal heat pump systems using mine water could reduce annual costs for heating
by 67% and cooling by 50% over conventional methods (natural gas or heating oil and standard air conditioning). 相似文献
4.
Abstract.
Scientists in most countries are assessed by the number of papers published in journals that are cited in the Science Citation index. This article reviews the mine water related entries in the Science Citation Index Expanded and discusses the results. Mine water relevant literature is spread over more than 900 journals, with 13 of them accounting for 25% of all relevant papers. No journal focused on mine water relevant issues can be found in the Index. 相似文献
5.
Sama Suresh Nirugatti Dinakar T. N. V. K. V. Prasad P. C. Nagajyothi Thoti Damodharam Arveti Nagaraju 《Mine Water and the Environment》2007,26(2):119-123
Abstract. An investigation was undertaken to determine the effects of a large barite mining operation on local ground water quality
near Mangampeta,Andhra Pradesh, India.Water samples were collected from drinking water wells in the mining and adjacent regions.
The drinking water in the mining region had sulphate concentrations that ranged from 211 to 589 mg/L, compared to sulphate
concentrations of 25 mg/L or less in the non-mined areas. The natural existence of barite and the widespread mine waste dumps
at Mangampeta are believed to be responsible for the higher levels of sulphate in the ground water. 相似文献
6.
Abstract.
The discharge of highly mineralised mine waters with
enhanced
226Ra and
228Ra activity concentrations has
affected creeks, rivers, sediments, soils, and plants along the
Lippe River and its tributaries.
226Ra activity concentrations were
elevated in all water samples receiving mine water, with
activity concentrations gradually decreasing with increased
distance from the colliery due to dilution and chemical
precipitation of radium with barium. Increased concentrations of
radium and radium decay products were also measured in sediments
and flood-affected soils. The sediments show an enrichment of
226Ra up to a factor of 750, while
the contaminated soils only reach a factor of 10. In aquatic
plants, a 4-fold increase in
226Ra activity concentrations was
measured downstream of the discharge points. The contamination
of the river banks and adjacent floodplain with radium is
responsible for enhanced gamma dose rates, which, along with the
incorporation of soil by playing children, provide potential
radiation exposure to the public. 相似文献
7.
Abstract A demonstration project was conducted to investigate treating acid mine water by alkaline injection technology (AIT). A total
of 379 t of alkaline coal combustion byproduct was injected into in an eastern Oklahoma drift coal mine. AIT increased the
pH and alkalinity, and reduced acidity and metal loading. Although large improvements in water quality were only observed
for 15 months before the effluent water chemistry appeared to approach pre-injection conditions, a review of the data four
years after injection identified statistically significant changes in the mine discharge compared to pre-injection conditions.
Decreases in acidity (23%), iron (18%), and aluminum (47%) were observed, while an increase in pH (0.35 units) was noted.
Presumably, the mine environment reached quasi-equilibrium with the alkalinity introduced to the system. 相似文献
8.
John J. Metesh 《Mine Water and the Environment》2006,25(2):108-113
Abstract. Nearly 10,000 miles (16,000 km) of underground mine workings began flooding on April 22, 1982 when the large pumps used to
dewater the mines of Butte, Montana were shut off. In the first few months, water levels in the workings rose hundreds of
meters. Flooding continues to this day at a slower rate, nearly 25 years later. An early evaluation of the water chemistry
in the flooding mines suggested that the initially poor water quality was the result of flushing of a reservoir of stored
acidity and metals. However, a detailed water balance for the Berkeley pit, underground workings, and associated mining features
suggests an alternative explanation. During the early period of mine flooding, acidic surface water from the deactivated heap
leach operations and nearby acid rock drainage were routed into the empty Berkeley Pit, and thence drained downward and outward
into the underground mine workings, causing widespread degradation of water quality in the underlying workings. After 21 months,
the hydraulic gradients in the system reversed, causing a change in the direction of ground water flow and a gradual improvement
in water quality of the mine shafts. 相似文献
9.
Abstract. In the Eastern Middle Anthracite field of Pennsylvania, a
formerly acidic (pH = 3.6) surface mine lake (initially
approximately 45,000m3 in volume) is
being reclaimed using fluidized bed combustor (FBC) ash. The pH
of the water in the pit dramatically increased when the alkaline
ash was added. The pH of the water is now well buffered, and has
not dropped below a value of 11.0 since March 2000. Analysis of
data from samples collected over the past six years indicate
that the lakes alkalinity is controlled by carbonate, silicate,
and hydroxide reactions. The relative importance of these
factors varies with ash input, and can be determined in a
predictable fashion. Laboratory tests determined that the mass
of CaO was more significant than the particle surface area on
the pH of the solution. Using only alkaline material, the
transition between caustic and carbonate alkalinity was
apparent, though this did not account for interaction with
silicate minerals, which should be considered when using
alkaline ash for reclamation. Field data indicate that with
time, the pH will again decrease but will be buffered by calcite
present on both the upper walls of the mine pool and within
pores of the FBC ash. Less than 1% of the ash is currently used
to increase the pH and alkalinity, so a large reserve exists for
long term buffering capacity. 相似文献
10.
Abstract Lakes develop when pits from open cut mines are left to fill with groundwater. In recent years, mining companies, mining communities,
and regulatory agencies have begun to consider potential beneficial end uses for mine lakes. Beneficial end uses are unlikely
to be without environmental impacts, however, and a proper consideration of the total benefit to the community should consider
them. This paper briefly reviews potential beneficial end uses and possible environmental impacts that might arise with them
for mine lakes in the Collie Basin, a coal mining region in Western Australia. We identified eight distinct, but not necessarily
incompatible, end uses from a search of the literature on mine lakes throughout the world: recreation and tourism, wildlife
conservation, aquaculture, irrigation, livestock water, potable water, industrial water, and chemical extraction. Recreation,
conservation, and possibly aquaculture use the mine lake directly, whereas the other end uses utilise extracted water. All
end uses have the potential to have environmental effects, with the most common being an actual or perceived impact on human
health and safety. A semi-quantitative risk assessment, using published literature sources, identified wildlife conservation
as the end use with the least environmental risk, and irrigation as the end use with the greatest environmental risk. Such
risks need to be balanced against economic and social benefits. There is an urgent need for a regulatory framework to address
mine lake options. 相似文献
11.
Abstract.
An isotopic and geochemical study of surface water and groundwater was undertaken at the Sullivan Mine, a sediment-hosted Pb-Zn massive sulphide deposit with a well-defined homogeneous Pb isotopic composition. The Pb isotopic composition of surface water and groundwater samples from near the mine site define a mixing line between Sullivan Pb and at least one other end member. The 18O and D isotopic results fall along an evaporation line that shows mixing between water from evaporative sources with water from meteoric sources. 相似文献
12.
Christopher H. Gammons 《Mine Water and the Environment》2006,25(2):114-123
Abstract. The Lexington tunnel is the last accessible underground mine working in the Butte, Montana mining district. Used as recently
as 1993, the tunnel and adjacent workings have been abandoned for over 10 years. Although the Lexington tunnel is over 200
m above the regional water table, perched water is present over much of its extent. Mine water near the portal is moderately
acidic (pH 4 to 5), with extremely high concentrations of metals, including Cu (up to 1000 mg/L) and Zn (up to 1400 mg/L).
In the middle reaches of the tunnel, the quality of the water is much better, with near-neutral pH, high bicarbonate alkalinity,
and lower concentrations of heavy metals. The low acidity and metal content is attributed to a lack of pyrite and other sulfides
in this portion of the mine, as well as the presence of carbonate minerals, such as rhodochrosite (MnCO3), in exposed veins. Sulfide minerals are more widespread further back in the tunnel, and are now oxidizing rapidly, leading
to pockets of severe acid drainage (pH< 3, dissolved Zn up to 5000 mg/L).
Geochemical modeling suggests that the near-neutral waters—the most voluminous type encountered in the Lexington tunnel—are
close to equilibrium saturation with rhodochrosite and hydrous Zn-carbonate (ZnCO3•H2O). The Eh of these waters is most likely controlled by redox reactions involving dissolved Mn2+ and secondary, Zn-rich, hydrous Mn-oxides. In contrast, the Eh of the acidic waters appears to be controlled by reactions
involving Fe2+ and Fe3+. Most of the acidic waters are saturated with K-jarosite, which forms delicate, straw-like dripstones at several localities.
Decaying mine timbers could be an important renewable source of organic carbon for heterotrophic microorganisms, such as iron-
and sulfate-reducing bacteria, especially deeper in the mine workings where the ground is saturated with anoxic ground water. 相似文献
13.
G. J. Van Tonder B. H. Usher I. Dennis P. D. Vermeulen 《Mine Water and the Environment》2007,26(2):79-87
Abstract: The main challenge facing many of the coal mines in South Africa is the management of mine water following the closure of
mining operations. The Sigma Colliery is situated in the Free State Province, adjacent to the town of Sasolburg and bordering
the Vaal River, one of the country's largest rivers. The mining includes both opencast and underground operations; however,
this paper will only discuss the main underground operations. There are several aquifer systems overlying the deeper mining,
which was done by bord and pillar and high extraction mining. Detailed conceptual models of the interactions between several
aquifer systems and the rebounding mine voids were constructed using mining and monitoring data. From this, numerical flow
models were used to model the complex flow system where rebound of water levels is expected. The results have led to an accurate
understanding of the complex flow system and the important controls on the final water levels in the area. 相似文献
14.
Abstract.
The effluent water produced by the washing process at the Al-Hisa and Al-Abyad phosphate mines in central Jordan was investigated in summer 2002. Twenty-four effluent and 10 ground water samples were collected and analyzed. There was a significant difference in water chemistry between input (groundwater) and output (effluent water) but, although the investigated area is highly fractured, the stable isotopic results indicated little or no mixing between the effluent water and groundwater in the area. This is attributed to the precipitation of clay-sized particles along the drainage channel. The quality of the effluent from the Al-Hisa mine was better than at the Al-Abyad mine, with electrical conductivity averaging 1474 µS/cm at Al-Hisa and 3250 µS/cm at Al-Abyad. The difference in effluent quality is attributed to slight lithological differences. At both mines, chloride was the predominant ion in the effluent water, with an average concentration of 669 ppm and 1299 ppm at the Al-Hisa and Al-Abyad mines respectively. The concentrations of heavy metals in the high-pH effluent water were very low, presumably due to precipitation and absorption onto suspended fine-grained particles. The effluent water from both mines was found to be relatively low in sodium and radiation, and suitable for the irrigation of salt tolerant plants. 相似文献
15.
Michael Royle 《Mine Water and the Environment》2007,26(2):102-109
Abstract: Between 1948 and 1999, gold ore containing high concentrations of arsenopyrite was mined at the Giant Mine near Yellowknife,
Canada. Processing resulted in 215,000 kg of gold and approximately 237,000 tonnes of highly soluble arsenic trioxide, a by-product
of the roasting process. The arsenic dust was collected and placed underground in 15 shallow chambers and stopes (within 75m
of the surface) with the understanding that the ground would revert to permafrost conditions once mining was completed. Subsequent
studies have shown that the ground is unlikely to refreeze naturally; therefore, it has been proposed to actively freeze the
arsenic trioxide storage areas to hydraulically isolate them from the post-closure ground water system. However, other arsenic
sources (backfilled tailings, etc.) exist deeper in the mine (600 m total depth), so there is a concern that arsenic will
leach into the minewater system and ultimately into the environment when the mine is allowed to flood. Therefore, the development
and implementation of a remediation plan for the site requires a good understanding of the arsenic distribution and expected
release to the mine water. To gain this understanding, a detailed program of surface and underground sampling was carried
out to identify or “type” the inflow sources to the mine, and their interaction with arsenic sources both on the surface and
within the mine workings. As of July 2005, the mine has been allowed to begin reflooding to reduce pumping costs and remove
the need for servicing pumps at the bottom of the mine, thus allowing the main shaft to be taken out of service. Prior to
starting reflooding, a multi-level monitoring system was installed in the main shaft and is currently being used to monitor
reflooding levels and water chemistry. Samples can be collected from each mine level intersecting the shaft. The system will
monitor reflooding rate and test how underground arsenic sources (backfilled tailings, etc.) are affecting water quality in
the mine. This geochemical information will be used to assess long-term arsenic loading from sources outside the frozen zone
and predict how long mine water treatment will be needed before natural ground water flow can be allowed. 相似文献
16.
Gammons Christopher H. Poulson Simon R. Metesh John J. Duaime Terence E. Henne Amber R. 《Mine Water and the Environment》2003,22(3):141-148
Abstract.
Groundwater being pumped from the flooded West Camp mine
workings of Butte, Montana, is elevated in hydrogen sulfide
(H2S), has a circum-neutral pH, and has
high arsenic but otherwise low metal concentrations. The daily
flux of H2S and As pumped from the
extraction well are each estimated at roughly 0.1 kg. Isotopic
analysis of coexisting aqueous sulfide and sulfate confirms that
the H2S was produced by bacterial sulfate
reduction. the mine waters are close to equilibrium saturation
with amorphous FeS, amorphous ZnS, siderite, rhodochrosite,
calcite, and goethite, but are undersaturated with orpiment
(As2S3). The
higher solubility of orpiment relative to other mental sulfides
allows concentrations of dissolved arsenic (~ 100 g/L) that are
well above human health standards. The West Camp waters differ
markedly from the acidic and heavy metal-rich mine waters of the
nearby Berkeley pit-lake. These differences are partly
attributed to geology, and partly to mining history. 相似文献
17.
Abstract.
This paper describes pilot scale tests of a novel process for the neutralisation of acidic mine water. Leachate from a waste coal dump was neutralised with limestone, and iron, aluminium, and sulphate were removed. Specific aspects studied were: the process configuration; the rates of iron oxidation, limestone neutralisation, and gypsum crystallisation; the chemical composition of the effluents before and after treatment; the efficiency of limestone utilisation; and the sludge solids content. The acidity was decreased from 12,000 to 300 mg/L (as CaCO3), sulphate from 15,000 to 2,600 mg/L, iron from 5,000 to 10 mg/L, aluminium from 100 to 5 mg/L, while the pH increased from 2.2 to 7.0. Reaction times of 2.0 and 4.5 h were required under continuous and batch operations respectively for the removal of 4 g/L Fe (II). The iron oxidation rate was found to be a function of the Fe (II), hydroxide, oxygen, and suspended solids (SS) concentrations. The optimum SS concentration for iron oxidation in a fluidised-bed reactor was 190 g/L. Up-flow velocity had no influence on the rate of iron oxidation in the range 5 to 45 m/h. Sludge with a high solids content of 55% (m/v) was produced. This is high compared to the typical 20% achieved with the high density sludge process using lime. It was determined that neutralisation costs could be reduced significantly with an integrated iron oxidation and limestone neutralisation process because limestone is less expensive than lime, and a high-solids-content sludge is produced. Full scale implementation followed this study. 相似文献
18.
Jae E. Yang Jeffrey G. Skousen Yong-Sik Ok Kyung-Yoal Yoo Hee-Joung Kim 《Mine Water and the Environment》2006,25(4):227-232
Abstract. There are hundreds of abandoned coal mines in Korea's steep mountain valleys. Enormous amounts of coal waste from these mines
were dumped on the slopes, contaminating streams with sediment and acid mine drainage. A limestone slurry by-product (lime
cake), which is produced during the manufacture of soda ash, was investigated for its potential use in reclaiming the coal
waste. The lime cake is fine grained, has low hydraulic conductivities (10-8 to 10-9 cm sec-1), high pH, high electrical conductivity, and trace amounts of heavy metals. A field experiment was conducted; each plot was
20 x 5 m in size on a 56% slope. Treatments included a control (waste only), lime (CaCO3), and lime cake. The lime requirement (LR) of the coal waste to pH 7.0 was determined; treatments consisted of adding 25,
50, and 100% of the LR. The lime cake and lime were applied either as a layer between the coal waste and topsoil or mixed
into the topsoil and waste. Each plot was hydroseeded with grasses, and planted with trees. In each plot, soils, surface runoff,
and subsurface water were collected and analyzed, and plant cover was measured. Lime cake treatments increased the pH of the
coal waste from 3.5 to 6, and neutralized the pH of the runoff and leachate of the coal waste from 4.3 to 6.7. Moreover, the
surface cover of seeded species was significantly increased; sufficient acidity in the coal waste was neutralized in the 25%
LR plots to allow seed germination. 相似文献
19.
Using the DRASTIC System to Assess the Vulnerability of Ground Water to Pollution in Mined Areas of the Upper Silesian Coal Basin 总被引:2,自引:1,他引:1
Abstract An attempt was made to use the U.S. EPA DRASTIC ranking system to assess the vulnerability of ground water in the Upper Silesian
Coal Basin. Analysis of the various system components indicate that several DRASTIC factors would have to be modified to consider
the effects of mining, subsidence, and ground water rebound. 相似文献
20.
Abstract.
This paper summarizes the dynamics and causes of the Stava disaster, and highlights some risky design procedures that led to the 19 July 1985 tailings dam failure. It then presents the Stava 1985 Foundation, which was formed to focus attention on such risks and to strengthen the culture of respect for human lives and safety. 相似文献