1. Introduction
Tailings are a by-product of all mining operations. In oil sands operations, tailings are made up of natural materials including water, fine clays and silts, left-over bitumen, salts and soluble organic compounds. [1] They also include solvents added to bitumen during the separation process. Tailings are discharged and contained in large earthen structures / Dykes above ground, known as tailings ponds. The larger sand particles in the tailings settle to form a stable deposit quickly, while the finer clay particles take longer sometime decades to settle and are known as fluid fine tailings. Proper tailings management can help in the faster reclamation of tailing ponds.
The major accumulations of oil sands are distributed geographically in eight countries: Canada, Venezuela, USA, Trinidad, Madagascar, Albania, Russia and Romania. Over 95% of the known in-place oil volumes occur in Canada, specifically in Northern Alberta. There are currently more than 176 square kilometers of tailings ponds in the Alberta. [1], [2]
Based on the Alberta Energy Regulator’s requirements and mandates in ERCB Directive 74, operators are required to have a stricter tailings management strategy, which has augmented the need for further research on ways to treat fluid fine tailings, with goal of developing technologies that will help the fine clays settle quicker or eliminate the need for storage ponds altogether. There is also a push towards reduction of fresh water make-up needs in oil sand extraction and processing.
This study report has mainly concentrated on the following areas such as:
• Identify and evaluate current tailings management technologies
• Evaluate the various objectives of tailings management.
• Study the current issues an...
... middle of paper ...
...ged, the coarse sand particles segregate quickly and form a beach, the remaining fine tails of 6–10 wt% solids accumulate in the tailing ponds. Fine tails settle quickly to 20 wt% solids content and over a few years to 30 wt% solids (86% by volume water) with a stable slurry structure, which is called mature fine tails (MFT). [3] This MFT will remain in a fluid state for decades because of its very slow consolidation rate. It has been predicted that if the existing tailings management practice was continued, the accumulated volume of MFT would increase from the current level of 400 million cubic meters to over one billion cubic meters by the year 2020. The accumulation of large volumes of MFT with a very stable fluid structure creates environmental concerns and long-term environmental liability. Figure 2 shows a schematic cross section of an oil sands tailings pond.
The Alberta tar sands have the second largest oil reserves in the entire world, only smaller than Saudi Arabia’s oil reserves. This vast supply of oil has created a large interest in the extraction and then production of different types of oil in Canada. The tar sands are believed to hold around 174.5 billion barrels of oil. The estimates are across the board but if it is true, the oil industry in Canada would become its largest export and substantially boost the economy. The tar sands were producing 53% of Canada’s oil output, but by the end of this year it will be around 83%. This number could increase to 99%, if the tar sands are fully taken advantage of. The extraction of oil has already begun and covers around 602 square kilometers of land. The problem is that ...
purpose we use this for is to drill wells into so that we may obtain the water that
Hoffman, Joe. "Potential Health and Environmental Effects of Hydrofracking in the Williston Basin, Montana." Serc.carleton.edu. Carleton College, n.d. Web. 26 Mar. 2014. .
The issue here is that the industries, alongside with the government that is currently ruling, still continues to dig out from this Earth and extract oil from the sands, most especially in Alberta which is located in the North America or also known as Canada. The Fort McMurray, the biggest land for mining oil from its sands in the country, is the best candidate of examples of this current issue that the country is facing when it is concerned about public safety and also, the water pollution. Fort McMurray's temporary tailing lakes contain a great volume of water, sand, clay, hydrocarbons, naphthenic acids, salt and other byproducts of the bitumen extraction and upgrading process. Even in -30 degrees, the hot waste sends a great amount of steam
The greenhouse gas emissions from the Alberta oil sands are up to 15 per cent higher than the crude oil processed in the United States because oil is too deep within the ground to be removed using conventional ways. The Athabasca Delta, where the oil sands are located, is a nesting ground for hundreds of species of birds. For the production of oil the land is cleared which destroys the breeding grounds. In the next twenty years over thirty millions birds will be lost. Large amounts of water are required for the production of the oil. To make one barrel of oil it takes three barrels of water. There is not enough water available to meet the needs of all planned oil sands projects while maintaining the stream flows. The flow of the Athabasca River from the town of Fort McMurray has declined by one third. A level-drop of a few centimeters of the river can prevent spring flooding. This is very important to fill nearby streams and wetlands. Also it can have an effect on the 31 species of fish and other marine life due to the drying up spawning and nursery sites. It is expected that the company will withdraw 529 million cubic meters of water from the Athabasca annually. There are over seven hundred and twenty billion liters of poisonous materials on the landscape in the Athabasca oil sands area. These toxic ponds cover an area of over 130 square kilometers. It is estimated that by 2040 these toxic ponds will cover over 310 square kilometers, an area the size of Vancouver. Tar sands mining operations are considered a threat to the Peace-Athabasca Delta because of the volumes of water that is drawn from the Athabasca River. The water cannot be sent back to the rivers because it has become toxic in the withdrawal process. Oil sands development causes large-scale disturbances to Alberta’s northern boreal forest which is an important carbon sink because it holds 22 per cent of the total carbon stored on the earth’s
Oil Sands are a type of bitumen deposit, the sands are naturally occurring mixtures of sand, clay, water, and an extremely dense and viscous form of petroleum called bitumen. They are found in large amounts in many countries throughout the world, but are found in extremely large quantities in Canada and Venezuela. Along with the local environmental and human-health impacts have contributed to the debate surrounding the resource. While many welcome it because it benefits the Canadian economy, Canada became U.S. and a curial energy source. To start off, a pro is that the oil sands have spurred massive economic growth in Alberta. Oil sands continue to generate huge profits to Canada and provide thousands of jobs for the residents including mining, research and
...osition of sand on the up current side due to the jetty interrupting the movement of sand.
Since the rise of the Alberta oil sands, the contribution of greenhouses gas emissions has been increasing dramatically. Alberta has only 10% of Canada’s population but emits the most greenhouse gases than any province. Also, the oil sands are the largest source of carbon dioxide emissions in Canada ("Oil Sands Truth." Para 4). Additionally, although it takes a lot of energy going into producing the bitumen from the oil sands, the energy output is relatively low. A about three times water is needed for one portion of bitumen when it is being processed after being accessed from the oil sands. Not only is water wasted, but the water supply n the area is heavily polluted. There is more than three million gallons of toxic run off from the plants every day. To contain this, majority of polluted water and tar is segregated and turned into toxic pools which are deposits of a combination of chemicals and polluted water. These pools now cover about fifty square miles in the oil sands location ("Tar Sands Oil: Pros and Cons." Para 1). To make room for the industry, the boreal forest is being cut down at a rapid pace. This not only depleted forest cover but the boreal forest counters the carbon emissions from the sands but with less forests, there will be an even greater rise in carbon emissions. The land is also being harmed due to the construction of large pipelines to access consumers far away. Not only do the oil sands harm the inorganic aspects of the environment in the location but animals are harmed due to their habitats being destroyed both on land and in the water ("Pros and Cons: Alberta Oil Sands." Para 4). The rivers and streams near the oil sands are being polluted and more fish and other aquatic animals are getting sick and dying. This in turn affects the individuals who fish for a living or acquire the fish as a main dietary source. With less fish to obtain,
In Somasundaran’s book, Oil Spill Remediation Colloid Chemistry-Based Principles and Solutions, he states, “[Lessons learned] have taught us that conventional mitigation techniques such as booming, skimming, and mechanical recovery cannot be fully relied upon to prevent oil from reaching shorelines and damaging sensitive ecosystems during a large-scale spill.” The most common oil spill cleanup methods involve trying to contain the spill with floating booms that prevent the spill from getting out of control. These are only possible if the spill is accessible within a few hours of happening, otherwise the area of the spill gets too large to contain with even the largest floating stoppers ("Oil Spill Cleanup Methods: How Do You Clean Up An Oil Spill? - Conservation Institute"). When the oil spill cannot be contained, the only options available require speeding up the natural breakdown of oil components. The first method for doing this is adding dispersal agents. These are chemicals that allow the oil to chemically bond with water. This prevents the slick from traveling over the water and increases the surface area of each oil molecule ("Oil Spill Cleanup Methods: How Do You Clean Up An Oil Spill? - Conservation Institute"). The cheapest way to clean oil spills is with biological agents that break down the oil into fatty acids and carbon
Fracking has become a highly controversial and publicized topic due to rising concerns and growing analysis into the mutual benefits of hydraulic fracturing to retrieve natural gas and oil reserves. With concerns of water pollution, mismanagement of toxic waste and irreversible
This paper describes equipment and techniques for responding to oil spills. Various techniques for the containment, cleanup and recovery of oil spills are examined; advantages and disadvantages of each are considered. Along with providing insight for oil spill response, this paper discusses environmental factors which can contribute to the success or failure of a cleanup operation.
Oil is a significant, non renewable resource that is found underground and extracted through technological processes (Grubb). Consumption rates of the substance have never been higher. Oil remains to this day a vital aspect of production in industries like plastics, fertilizers, and asphalt. World oil consumption presently rests around 83 million barrels per day (...
Acid Mine Drainage For hundreds, even thousands of years, human beings have mined for metals and stones, and with the advent of greater technology as well as greater needs, the demands for these resources continue to grow. While these resources benefit our lives in many ways, the effects of mining can be detrimental, and one such effect is the topic of this essay, acid mine drainage (A.M.D.). The Causes of A.M.D. will be discussed, along with some of the physical and biological problems associated with it. Some prevention and remediation treatments will also be considered.
chemicals. In order to avoid polluting the water we spread the manure and slurry when
Mine Tailings. (2008). The University of Arizona Superfund Research Program (SBRP). Retrieved February 12, 2011, from http://superfund.pharmacy.arizona.edu/Mine_Tailings.php