Showing posts with label Mine Pollution. Show all posts
Showing posts with label Mine Pollution. Show all posts
Sunday, 29 July 2018
Environmental Engineering Questions and Answers
July 29, 2018Educational, Legislation, Mine Pollution, Mine Waste Management, Mine Waste Management Forum, Mineral Processing
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1. Define environment (in
terms of mining).
Environment
is Conditions that affect working atmosphere and development of mining. Or is
the physical condition that exists in mines.
2. What is mining?
It is the
extraction of minerals from the earth.
3. Why does environment become
a subject to mining?
Because serious mine closure issues remain
after mine is closed so by taking environment as a subject to mining, the mine
closure issues can be addressed and must be known to the local people of what
is going on and what preventive measures that can be taken to protect people
and the natural environment.
4. What are main sources of
physical impacts by mining operations?
They are:
exploration, development and extraction.
5. What are main sources of
chemical pollution due to mining?
Main sources
of chemical pollution are cyanide and sulfuric acid for (leaching) and organic
reagents (flotation agents) from ore separation processes. Others include
mercury, toxic blast chemicals and hydrocarbon products run – off.
6. What particular problem
exists with both ferrous and precious metallic ores?
Acid mine
drainage is a particular problem in many mines and both ferrous and precious
metallic ores are the main sources of ARD.
7. What is the main concern of
trace metal concentrations?
The main
concern of trace metal concentration is that, when they are leached into the
river systems and streams it cause bioaccumulation which is a concern to the
river systems.
8. State the magnitude of
mineral’s contributions to economic growth in developed and developing nations.
High
proportions of minerals are mined in developing countries and so the economy of
poor countries depends largely on minerals whereas minerals contribute a small
portion to the economy of developed countries like USA, Japan and Great
Britain.
9. What are the effects of
increased demand for minerals?
The demand
for minerals increased as there was an increased in technology, development and
human civilization. As a result, environmental impacts of earth based resource
extraction increases.
10. Why is every mine different
and related environmental effects?
Because every
mine has different characteristics with respect to environment. These characteristics
include;
11. Describe very briefly how
mineral is extracted by surface mining methods and underground methods.
In surface
mining method, the mineral is extracted by removing the overburden, drilled, blasted,
loaded and hauled to the processing plant.
In underground
mining methods, mineral deposits are extracted at certain depths. Ore is
drilled and blasted stopes, marked and hauled to the surface via hoisting
systems or diesel units.
12. What aspect of operation
distinguish surface from underground mining?
Underground
mine operations are complex compared to surface operations. Surface mining is
easy and cheap to operate because the ore deposit is near surface whereas underground
mining is hard and expensive to operate because mineral deposit is at certain
depth.
13. State the natures of environmental
impacts caused by mill operation, underground and surface mining respectively.
Riverine
Tailings from mill operation is dangerous as most mineral deposits are
associated with sulfur. In addition, smelting generate large amount of toxic
gas. Smelters cause regional pollutions where SO2 can travel considerable
distances and cause “acid rain” and climate change.
Potential
sources of water pollution include drainage from surface and underground mines,
waste water from beneficiation, and contaminated surface water from toxic blast
chemicals and hydrocarbon products run – off.
14. Why is chemical pollution
more serious than physical?
Because
chemical means are hard to reverse and these must be controlled at process
stage. But environmental impacts through physical impacts can be reclaimed
through rehabilitation during mining and post – mine period.
15. Differentiate tailings and
waste rock and describe respectively environmental impacts.
Tailings
compose mostly of mud and slurry containing high proportion of fine particles.
Mud and slurry tailings once exposed to air and rain cause oxidation, releasing
sulfuric acid, causing acid rock drainage. The suspended solids cause river bed
sedimentation, diversion of watercourses, flooding and destruction of aquatic
life.
Waste rock is
solid coarse materials from both surface and underground mines. Waste rock dump
occupy large portions of land, often outside the special mining lease under
lease for mining Purposes.
16. If Frieda Copper mine is
predicted to produce 1million/year ore at 0.45%Cu, what is the annual waste
material generated?
Data:
production = 1,000,000 tonness/year
grade = 0.45%
Annual waste
generated =????
Copper
concentrate = production x grade = 1,000,000 x 0.0045 = 4500 tonnes copper.
Annual wastes
= 1,000,000 – 4,500 = 995,500 tonnes of waste.
17. If Hidden Valley mine has
minable ore of 5minllion tones grading 2.5g/t Au, for mine life of 10 years,
the tailings dam should be designed to what capacity?
Data:
mineable ore = 5 million
Ore grade =
2.5g/t mine life = 10 years.
/year x 2.5g/t = 12,500,000 grams/year.
Total value
mineral = 10 years x 12,500,000 gram/year = 125,000,000 grams
In terms of tonnes = 125 tonnes.
Waste and
value minerals = 5,000,000 tonnes /year x 10 years = 50,000,000 tonnes of ore.
Therefore;
total waste generated would be = 50,000,000 tonnes – 125 tonnes = 49,999,875
tonnes.
So the
tailings dam should be designed in such a way that will cater for 49,999,875
tonnes of waste over the ten year period. If tonnage factor was given then the
answer would be expressed in volume.
18. What is beneficiation?
Describe it?
Is the entire
process of crushing, grinding, sizing and separation of ore into valuable
mineral and waste
In other
words it is the process that liberates mineral grains locked in rock/ore which
can be separated physically and chemically.
19. State the two types of
mineral separation and examples of each.
Two basic
means of separation are physical and chemical.
·
Physical separation involves; - (a) magnetic and (b) gravity separation.
·
Chemical separation methods are: (a) floatation (b) cyanidation (c)
amalgamation and (d) heap leaching.
20. Briefly describe the
processes: (a) heap leaching (b) cyanidation & (c) amalgamation.
Wednesday, 14 February 2018
Environmental Impacts of Artisanal and Small Scale Gold Mining in Papua New Guinea
February 14, 2018Artisanal Small Scale Mining, Gold, Learning Material, Mine Pollution, Mining Technologies, Safe Handling of Mercury
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The small scale gold fields are mainly
riverine deposits where mining occurs along river banks, terraces and in active
river channels. Using poorly constructed sluice boxes, gold bearing material is
fed into the inclined sluice boxes. The box is constructed using plywood or
flattened roofing iron with wooden/metal ripples. These types of operations are
associated with low to very low recovery because of uncontrollable river flow
rates, incorrect inclination of the sluice boxes and inappropriate amounts of
feed material at any one time. It is extremely difficult to introduce
mechanised alluvial mining because of low skills and knowledge, isolation from
transport infrastructure and lack of basic infrastructure.
The
gold bearing gravels are concentrated by rippled sluice boxes. The fine gold is
not commonly trapped in the ripple compartments. The fine particles of sand
with gold in it are than poured into the panning dish for further panning. Mercury
is placed in into the panning dish to concentrate the fine gold particles.
Amalgamation is an efficient mean of extracting gold particles from
concentrates after panning or sluicing.
Health
and environmental impacts (Watch Video)
The
artisanal and small scale gold mining provides employment at local and national
levels, and the sector is an important source for the inflow of foreign
exchange into rural communities. However, small scale mining activities are
associated with sensitive health and environmental issues.
The
process of recovering gold by retorting and heating the amalgam over an open
fire is a dangerous practice. The open fire could be in houses or at river
banks and thus a whole family could be exposed to poisonous mercury fumes.
Concentrate from
sluicing near streams is usually mixed with mercury and a considerable amount
of mercury is lost to the streams. Apart from direct inhaling of mercury fumes
by miners, aquatic life also feeds on mercury lost into the river, which are
then eaten by the locals through the food chain. The Watut and Bulolo Rivers
has been subject to prolonged mercury contamination and discharges of
hydrocarbon wastes. The Watut people depend on the river for fishing, washing
and farming on the river banks.
Some miners in old
shafts and adits and they are consequently exposed to the trapped noxious gases
such H2S. Locals have been reported that they are buried alive when they burrow
through soft oxidized lodes or vein systems.
Some operators
locate their sluice boxes in streams, thus polluting the water. Silting and
stream discolouration are very common. Farmlands are usually destroyed by
mining activities. Locals even uproot big trees along structurally defined thin
gold deposits. Sometimes, the narrow gullies are not rehabilitated and are left
to be taken care of by nature.
Exposed and
disturbed lands are subject to soil creep widening the flow channels, and
debris avalanches are common along rivers at the active mining areas. The loss
of fertile land due to small scale mining puts socio-economic pressure on the
local society. Old gravel pits are usually abandoned without reafforestation.
Pits filled with stagnant water are common.
Education and training
Small-scale
mining technology in most developing countries is simple and attracts many
unskilled people. The desire for economic and social survival has attracted
many people to the industry. The law expects the licensed small-scale miner to
mine using effective and efficient methods, and observe good mining practices,
health and safety and protect the environment.
The Small Scale
Mining Branch of PNG Mineral Resources Authority (Formerly Department of
Mining) in Wau, Morobe Provine has created education and training materials for
the miners. The Department has produced seven booklets and DVDs on
•
Simple Gold Mining;
• Basic Mining Practice;
• Advanced Mining practice;
• Handling of Mercury;
• Occupational Health and Safety;
• Environmental Issues; and
• Economics of Mining.
The major focus
of the training resources is to ensure that small scale operations are safe,
environmentally friendly and economically viable.
Small-scale
mining operations in most developing countries have serious negative environmental
impacts. One of the major factors is the implementation of the associated
mining Acts which are lacking.
Donor agencies
like the World Bank, European Union and Japanese International Cooperation Agency
(JICA) have in recent times shown keen interest in the negative and positive
impacts of the PNG’s ASSM sector. AusAid and the World Bank have sponsored the
building of the ASSM sector capability in PNG through legislative framework and
training and awareness on the use of mercury.
Note: This article is a reproduction of a learning material with inclusion of up to date information.
Reference
[1] Ail, K. K. (2005. Kwoe River
Alluvial Gold Deposit Evaluation and Development Plan, PNG University of
Technology, Lae.
Sunday, 28 January 2018
Data Analysis of Rapid PACKTEST Results
January 28, 2018Learning Material, Mine Pollution, Mine Waste Management, Rapid PACKTEST, Water Quality Monitoring Technique
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Upon the completion of the setup and PACKTEST, you have the data
available at hand to record. In your note book you record the readings of pH,
Turbidity, Temperature, metal conductivity. Then you have the other sets of
data from the PACKTEST results. Each element tested has got a numbered color
range that corresponds to the concentration of that element/compound in the
water sample. You record every data for the elements that are tested.
![]() |
| Table 1 Rapid PACKTEST Results |
Be careful to graph the related data so that any conclusion drawn can
make sense with respect to particular information. i.e. if you plot all the
data into one graph then always take note of the legends so that your
interpretation is accurate in reporting.
It is also better to take readings at different weather patterns
i.e. during rainy seasons and dry seasons. Remember to keep the sample points
unchanged so that a good comparison is made.
From the data analysis, it is better to make few comments and off
course a recommendation is anticipated from the field investigation. Your
recommendation should provide a clear direction/ indication should there be precautions
taken within the vicinity of the impacted project area especially the mine
impacted communities. Your recommendation should also alert the local
government authorities regarding the findings and what to do in that part of the
area.
Characteristics of Zeolite Ore
January 28, 2018Learning Material, Mine Pollution, Mine Waste Management, Mine Waste Treatment, Zeolite Ore
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- Like any other matters, Zeolite has two major characteristics which are:
1. a chemical composition having
zeolitic water, and
2. An excellent ion exchange
capability.
Zeolitic water is unique in the composition
which is hardly observed in other minerals, as dehydration occurs without
changing the crystal structure under heating. This hydration behaviour enables
zeolite to be used as moisture absorbent.
In addition, the dehydrated
zeolite has a myriad of holes like a honeycomp and the holes have such small
sizes in the order of angstroms (Symbole:Ã…,
unit cm/100 million).
Accordingly a mixture of gasses with different molecular sizes, which are
chemically difficult to separate at the molecular level, can be sieved through
zeolite. This is called the “molecular sieve effect.”
The Cation exchange
capacity of zeolite is explained as follows:
The general chemical
composition of zeolite in general is indicated by
(M2+,M2+)O.Al2O3.mSiO2.nH2O.
The symbols
in the parentheses at the beginning of the formula indicate exchangeable
cations. Cations in zeolite are exchangeable with other cations in aqueous
solutions. In chemical terms, material with a positive charge is referred to as
a base. The ability to exchange bases is Base Exchange capability (or cation
exchange capability), while the capacity to exchange bases is base exchange
capacity (or cation exchange capacity) and is called C.E.C., the acronym for
“Cation Exchange Capacity.”
Ion exchangeability allows
silicon (Si) atoms located in the centre of the zeolite crystal lattice to be
partially replaced with aluminium (Al) atoms, resulting in the loss of cations.
Cations such as sodium (Na), Calcium (Ca) are captured in the crystal lattice
to compensate for the shortage.
The function of C.E.C. is
similar to that of the liver of an animal which stores nutrients. Zeolite
adsorbs and stores fertilizer components (bases) such as sodium, potassium and
calcium to supply the nutrients (fertilizer components) to crops in response to
request.
The unit of cation exchange
capacity is represented by mg equivalent (meq) per 100g of soils or zeolite
rocks.
The cation capacities of clay
minerals are different depending on the type of minerals. Montmorillonite is
the main mineral source for bentonite which exhibits the highest C.E.C. after
zeolite.
Reference:
Boiling
stone (zeolite), Zeolite Dynamics, Lecture Notes.
Roskill
Report (1990)
Annual
Reports of Various Companies.
Nouko
to Engei (Agriculture and Horticulture), September 1978.
JACT
News.
Tuesday, 16 January 2018
Data Collection of Rapid PACKTEST Results
January 16, 2018Learning Material, Mine Pollution, Mine Waste Management, Rapid PACKTEST, Water Quality Monitoring Technique
2 comments
Data collection is the recording and assembling of results obtained from the Rapid PACKTEST experiments at various locations.
Before you conduct the packtests, you need to have the required materials for preparation, experiment and recording of data. The materials and equipment you would require for testing include but not limited to:
Packtest Kits.
GPS
Note Book
Pencil/pen
3 x Half cut container
syringe
0.45µm filter
Camera/smart phone with camera.
turbidity meter
pH meter
Laptop/computer
Once you have the above equipment list, you are about to conduct the PACKTEST and other necessary measurements. But before that you must never forget to give a sample location name or sample code/ID and record the coordinates, location zone and offcourse altitude of the sample location. This will ease the management of various data of the same type.
Thereafter, you proceed with the PACKTEST procedures as outline below which is a global practice:
Sampling Procedure for PACKTEST
1. Fetch water in container and filter the water using syringe and 0.45µm filter to filter water sample and pour filtered water sample into a clear mini cylinder(half cut container).
2. Remove the colored line at the top of the tube to clear the aperture.
3. Press tube's sidewall to expel air, and hold the tube.
4. Immerse the aperture of the tube into the water sample in the mini cylinder and release to fill the tube halfway.
5. Shake the tube slowly for few seconds.
6. Wait for the reaction time as indicated in the instruction manual, and then compare the actual color in the tube with provided Standard Color. The nearest color indicates the concentration value (mg/L = ppm) of the analyte in your sample.
Concurrently set up the equipment for measuring the pH, temperature, metal conductivity and turbidity of the water sample at the same sample location for the packtest water sample taken. After the setup is complete, you take the reading carefully as the reading varies every second. It is recommended to take the best average reading.
Upon the completion of the setup and PACKTESTs, you have the data available at hand to record. In your note book you record the readings of pH, Turbidity, Temperature, metal conductivity. Then you have the other sets of data from the PACKTEST results. Each element tested has got a numbered colour range that corresponds to the concentration of that element/compound in the water sample. You record every data for the elements that are tested.
Finally you need to digitise the data and analyse the test results. To do that, you need to have a computer or a laptop. Create an excel spread sheet in your laptop or computer and enter the field data in a tabulated format. Your sample results look like the table below:
How to do data analysis from the PACKTEST results and other measurements is in a different article (Data Analysis of Rapid PACKTEST Results)
Related Articles:
Rapid PACKTEST
Data Collection of Rapid PACKTEST Results
Data Analysis of Rapid PACKTEST Results
How to Conduct Rapid PACKTEST in a Well
Before you conduct the packtests, you need to have the required materials for preparation, experiment and recording of data. The materials and equipment you would require for testing include but not limited to:
Packtest Kits.
GPS
Note Book
Pencil/pen
3 x Half cut container
syringe
0.45µm filter
Camera/smart phone with camera.
turbidity meter
pH meter
Laptop/computer
Once you have the above equipment list, you are about to conduct the PACKTEST and other necessary measurements. But before that you must never forget to give a sample location name or sample code/ID and record the coordinates, location zone and offcourse altitude of the sample location. This will ease the management of various data of the same type.
Thereafter, you proceed with the PACKTEST procedures as outline below which is a global practice:
Sampling Procedure for PACKTEST
1. Fetch water in container and filter the water using syringe and 0.45µm filter to filter water sample and pour filtered water sample into a clear mini cylinder(half cut container).
2. Remove the colored line at the top of the tube to clear the aperture.
3. Press tube's sidewall to expel air, and hold the tube.
4. Immerse the aperture of the tube into the water sample in the mini cylinder and release to fill the tube halfway.
5. Shake the tube slowly for few seconds.
6. Wait for the reaction time as indicated in the instruction manual, and then compare the actual color in the tube with provided Standard Color. The nearest color indicates the concentration value (mg/L = ppm) of the analyte in your sample.
Concurrently set up the equipment for measuring the pH, temperature, metal conductivity and turbidity of the water sample at the same sample location for the packtest water sample taken. After the setup is complete, you take the reading carefully as the reading varies every second. It is recommended to take the best average reading.
Upon the completion of the setup and PACKTESTs, you have the data available at hand to record. In your note book you record the readings of pH, Turbidity, Temperature, metal conductivity. Then you have the other sets of data from the PACKTEST results. Each element tested has got a numbered colour range that corresponds to the concentration of that element/compound in the water sample. You record every data for the elements that are tested.
Finally you need to digitise the data and analyse the test results. To do that, you need to have a computer or a laptop. Create an excel spread sheet in your laptop or computer and enter the field data in a tabulated format. Your sample results look like the table below:
![]() |
| Table 1: Rapid PACKTEST Results |
Related Articles:
Rapid PACKTEST
Data Collection of Rapid PACKTEST Results
Data Analysis of Rapid PACKTEST Results
How to Conduct Rapid PACKTEST in a Well
Saturday, 15 July 2017
Mine Waste Disposal in Papua New Guinea
Mine waste disposal is any waste related to mining is disposed into any environment. Environment could be land, river or deep sea or tailings dam. Waste can be either solid or slurry.
Most of the mining companies in PNG provide shallow reasons to government to allow them to dispose mine waste into river or deep sea tailing placements.
Most of the mining companies in PNG provide shallow reasons to government to allow them to dispose mine waste into river or deep sea tailing placements.
Some of these factors include but not limited to:
- Topography
- Climatic conditions.
-Geological structures with respect to seismic activities.
- Soil/rock competency etc..
- Topography
- Climatic conditions.
-Geological structures with respect to seismic activities.
- Soil/rock competency etc..
The above are the factors that pose threat to the tailings dam construction, thus developers propose to dump tailings into riverine and deep sea tailings placement.
Hidden Valley mine and K92 mine have built TSF and it is anticipated that other new mining projects could build TSF.
PNG should completely discourage riverine tailings and DSTP in PNG and encourage TSF to save PNG from mining waste management issues.
Hidden Valley Mine Tailings Storage Facility (TSF)
Tuesday, 27 June 2017
Relationship of pH and Conductivity of Heavy Metal Contents under Rainy Condition
pH increases as the conductivity is low in water. Heavy rain can increase the conductivity of heavy metals contents in water which reduce the pH of water.
During heavy rain you would expect a higher reading for conductivity and turbidity on the turbidity measuring equipment. at the same location and during dry days you would expect a different reading with low pH values.
During heavy rain you would expect a higher reading for conductivity and turbidity on the turbidity measuring equipment. at the same location and during dry days you would expect a different reading with low pH values.
Tuesday, 13 June 2017
Possible Mine Pollution in a Metal Mine
June 13, 2017Learning Material, Mine Pollution, Mine Waste Management, Mine Waste Treatment
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In an event when rain fall, water seepage cause subsidence of overburden materials. Rain water reacts with acid forming rocks and generate acid mine drainage (AMD). The ionized water flows with lose particles of materials known to be sediment runoff which eventually becomes the tributary of a nearby stream. Consequently the pH is reduced at the nearby stream.
Sometimes structures of facilities fail and waste water is released into the environment without proper treatment and this is a concern for environment pollution along the riverine inhabitants.
In sulfide mines the possible pollution are:
- Acid drainage from mine adit
- Surface exposure to atmosphere and moisture
- Tailing dam gradually eroded by river water
- Bursting of waste rock/tailing dam
- collapse of abandoned dressing plant.
Tuesday, 2 May 2017
Mining and Natural Environment
May 02, 2017Landholder Grievances, Learning Material, Mine Pollution, Mine Waste Management, Mine Waste Treatment
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Mining is one of the old human activities just like agriculture, fishery, forestry, manufacturing etc. Human lives are supported by obtaining and utilizing mineral resources from the earth's crust.
The Distinctive Features of Mines and Mining include but not limited to the following:
The Distinctive Features of Mines and Mining include but not limited to the following:
- Non-renewable assets - Mining Industry is based on non-reproducible and depleting assets.
- Location - Mining takes places where the ore body is reachable at economic value.
- Environment Impacts - Mining may disturb and contaminate the surrounding environments.
- Local Community Relations - Usually mines are located in the remote areas, thus close relationship with local communities is strongly encouraged.
- Working Condition - Occupational Health and Safety are the first priorities of mining.
- High Risk and Vulnerability - Mining Projects are susceptible to a variety of risks.
- Long Leading Time - Engineering works and permission to open a new mine need a longer term.
- Required Engineering Ability - Stable and successful mining is likely dependent on a combination of widely used practical technologies.
- Capital Advantage - Intense capital is required for continuous prospect or explore new deposits and endure risky business.
Out of the distinctive features of mines and mining, one of the most critical agenda around the globe is the Environment Impacts related to mining.
Environment Impact in mining is unavoidable but can be controlled to minimize the aftermaths. Mining is a backbone of a country's economic growth. In Papua New Guinea(PNG), the country's economy is mostly dependent on the extractive Industry which include Mining and Petroleum.
Some people in PNG speak negative about mining and encourage the protection of the natural environment. It should be understood that, before gardening, it must be cultivation of the land for farming. Then sacrifice the vegetation to farm the land. Similarly, the forest and the surrounding environment is sacrificed to mine out what is on/beneath the earth's crust including ocean floor.
There are legislations, prevention and treatment techniques available to safeguard and protect the environment from the waste generated from the mines.
Monday, 1 May 2017
Mercury Pollution and Prevention Measures In Papua New Guinea
May 01, 2017Learning Material, Mine Pollution, Mine Waste Management, Mining Regulators, Safe Handling of Mercury, Training
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Mercury is a heavy silvery-white liquid metal used in some thermometers and barometers. (Symbol: Hg). It is also used to extract fine gold from the mixture of fine sand. Dispose of mercury into the environment is harmful.
Mercury is used in many ways and people do not realize when it gets released into the environment which in turn causes mercury pollution.
In Papua New Guinea almost all Small Scale Miners use mercury in the amalgamation process during gold recovery from the fine sands. Mercury is used in different ways to recover gold. some pour in between the riffles on the sluice boxes in an attempt to capture fine-grained gold.
The contact time between the gold and mercury is not effective for the amalgamation to occur. Often fine gold remains suspended in the flow of particles above the riffles and does not settle to contact the mercury. Thus, about 30 percent (%) of the mercury used in sluice boxes in PNG is released into the river systems. This is actually a treat to the environment.
The Mineral Resources Authority's Small Scale Mining Branch in Wau- Morobe Province try its best to train local miners, especially small-scale miners, on the Safe Use and Handling Of Mercury in the process of amalgamation. The Training Center also trains the miners on other alternatives to be used in the gold recovery process to avoid the use of mercury.
Other alternative methods of gold recovery techniques the small scale miners should be looking at would be Gravity Separation methods in the recovery of fine gold.
Gravity separation methods are vital and the best alternatives to engaged instead of Mercury. Such methods include, but are not limited to:
Mercury is used in many ways and people do not realize when it gets released into the environment which in turn causes mercury pollution.
In Papua New Guinea almost all Small Scale Miners use mercury in the amalgamation process during gold recovery from the fine sands. Mercury is used in different ways to recover gold. some pour in between the riffles on the sluice boxes in an attempt to capture fine-grained gold.
The contact time between the gold and mercury is not effective for the amalgamation to occur. Often fine gold remains suspended in the flow of particles above the riffles and does not settle to contact the mercury. Thus, about 30 percent (%) of the mercury used in sluice boxes in PNG is released into the river systems. This is actually a treat to the environment.
The Mineral Resources Authority's Small Scale Mining Branch in Wau- Morobe Province try its best to train local miners, especially small-scale miners, on the Safe Use and Handling Of Mercury in the process of amalgamation. The Training Center also trains the miners on other alternatives to be used in the gold recovery process to avoid the use of mercury.
Other alternative methods of gold recovery techniques the small scale miners should be looking at would be Gravity Separation methods in the recovery of fine gold.
Gravity separation methods are vital and the best alternatives to engaged instead of Mercury. Such methods include, but are not limited to:
- Recovery of Fined Size of gold grain should use Shaking table, Humphreys spiral, Pinced sluices, Reichert cone, etc..
- Recovery of more finer gold particle should use Nelson concentrator, Falcon concentrator.
The mercury released into the environment is unaccounted for and undetected. Mercury can be detected by a Rapid Pack-test by use of Rapid pack test kits. However, rapid pack test is not available in the country and it is anticipated that pack-test kits will be imported from overseas to use for training and study purposes.
The next strategy is to ban import of mercury and introduce the alternative gold recovery methods and draft a treatment strategy through research and training.
Friday, 28 April 2017
Abandoned Mines and Possible Issues
Acid Mine Drainage (AMD) is a common issue in abandoned mines. AMD is produced by oxidation of pyrite (FeS2) and AMD also contains heavy metals.
After the exploitation of sulfide minerals in the metals mines, heavy metals such as pyrite, chalcopyrite, sphalerite, galena and other minerals that are not mined during the mining operation. The remaining minerals react over time with groundwater and oxygen and produce acid mine drainage that heavy metals are contained in it.
Tailings dam where tailings of mine related waste are dumped into the tailings dam or Tailings Storage Facility (TSF) become a source of mine pollution as seepage. Metals in the seepage water from the tailings dam dissolve out with rain and surface water which eventually contribute to the issues.
The content of heavy metals reduces the pH level of Water and reduces the quality of water which people commonly refer to as mine pollution.
After the exploitation of sulfide minerals in the metals mines, heavy metals such as pyrite, chalcopyrite, sphalerite, galena and other minerals that are not mined during the mining operation. The remaining minerals react over time with groundwater and oxygen and produce acid mine drainage that heavy metals are contained in it.
Tailings dam where tailings of mine related waste are dumped into the tailings dam or Tailings Storage Facility (TSF) become a source of mine pollution as seepage. Metals in the seepage water from the tailings dam dissolve out with rain and surface water which eventually contribute to the issues.
The content of heavy metals reduces the pH level of Water and reduces the quality of water which people commonly refer to as mine pollution.
| Photo: Example of Abandoned Mine - Mt.Sinivit Gold Mine, PNG. |
Wednesday, 19 April 2017
Water Pollution
April 19, 2017Learning Material, Mine Pollution, Mine Waste Management, Mine Waste Treatment
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Water Pollution is of two types. Waste Water Pollution and Mine Water Pollution. Mine water pollution is induce when water from the mine or rain water passes through exposed acid forming rocks/minerals. Waste water pollution is when the miner/operator of the mining project discharges the waste water containing heavy metals into the environment. Both of them causes the pH of the water/creeks/rivers to be lower than 7.
Some mines treat the waste water and raise the pH level up to 10 at the water treatment plants before discharging into the environment.
Waste water can be treat and controlled by active treatment and mine water can be actively treated or passively treated. Active treatment of mine water is an expensive exercise.
Mine Water pollution and its treatment is a challenge for all the Mining Regulators in the world today. Most tributary creeks/rivers of the polluted creeks/rivers have higher pH which can dilute the polluted creek/river and raise pH level.
One of the challenges face by the riverine communities is turbidity which affects the drinking water quality and also the diversion of river course which affects the riverine communities as well.
Tuesday, 18 April 2017
Mine Waste Management
April 18, 2017Learning Material, Mine Pollution, Mine Waste Management, Mine Waste Management Forum, Mining Regulators
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Mine Waste refers to the waste related to mining activities such as tailings, waste rock, sediment, chemical residues, etc . Management refer to how the mine derived waste is managed by the operator and or the Regulatory Bodies.
This site welcomes critics and comments and suggestions related to the Mine Waste Management to improve the lives of people living within the vicinity of mine impact areas.
Subscribe for latest updates and comment for discussions and questions on our Forum Page
This site welcomes critics and comments and suggestions related to the Mine Waste Management to improve the lives of people living within the vicinity of mine impact areas.
Subscribe for latest updates and comment for discussions and questions on our Forum Page













