Optimizing Artificial Lift Through Enhanced Control Systems

Canada is the world’s fifth largest oil producer. This is due in large part to the country’s vast reserves in and around Alberta, which contains the third-largest known oil reserves in the world.

Calgary-based ARC Resources Ltd. has called this oilrich region home for more than 20 years. The company has assets distributed across western Canada and operations that include E&P and development of conventional oil and natural gas.

Just across Alberta’s western border in northeast British Columbia, ARC Resources is one of the largest operators in the Montney region, which is considered one of the best tight gas plays in North America. And it was here that ARC Resources recently decided to begin optimizing the control systems it was using for its large multiwell natural gas production sites. The existing systems in place at these sites didn’t support artificial lift, which would soon be needed to maintain production levels. The systems also presented both expansion and safety challenges that the company wanted to address.

Operations at a crossroad

ARC Resources already had optimization programs at its smaller pads that contained only one to four wells. Control systems in place at these pads supported the use of artificial lift systems to help maintain or increase production as these wells depleted.

Larger pads of five or more wells, however, lacked control systems to support artificial lift systems. As some of these sites approached production milestones of 10 to 15 years, the company knew that it would need to make improvements in the near future.

“We were very successful with using assisted lift to keep production stable in the smaller fields,” said Charlie Kettner, programming specialist for ARC Resources. “We didn’t have the same optimization option in our bigger pads. So our production engineers wanted to find a control solution that would allow us to bring artificial lift to these fields as well.”

The existing controllers were not capable of handling the large amount of integrated operations required to run the entire well pad. As a result, the company had to use multiple controllers hardwired together along with remote terminal units (RTUs). This approach not only made the control infrastructure more complex and thus more prone to mistakes but also limited the amount of information available for control and monitoring.

The use of multiple hardwired controllers also presented safety challenges. ARC Resources relies on its control architecture to monitor toxic and explosive gases and to take actions such as turning on an exhaust fan or blocking wells as conditions dictate. But the controllers could lock up and freeze their outputs and give no indication that there was a fault. This forced the company to add “watch dog” timer hardware to monitor for such conditions.

A ‘canned package’

Kettner reached out to Rockwell Automation to begin discussions about optimization options that would support artificial lift systems at the large multiwell pads as well as simplify control and address safety concerns.

Their talks led them to the ConnectedProduction well manager system from Rockwell Automation, which includes an out-of-the-box Allen-Bradley ControlLogix programmable automation controller (PAC) and FactoryTalk View human-machine interface that requires no custom coding. The PAC gives ARC Resources single-platform control for large sites with up to 32 artificial lift wells and contextualized production information to help operators maintain optimal production levels and troubleshoot issues.

“It’s a canned package,” Kettner said. “You order it, install it and plug in your data to the points it’s looking for, and away you go.”

Kettner and his team decided to pilot the new technology at an eight-well production site named Sunrise near the town of Dawson Creek, British Columbia, before installing it at four other multiwell pad sites.

One of the benefits they first discovered during this trial run was the add-on instructions included in the ConnectedProduction, which helped them save about two days of programming during the installation process. Because the technology uses an open architecture, integration with other vendor hardware at the site was easy.

Enhanced visibility and safety

ConnectedProduction has eliminated the need for multiple controllers and RTUs that were previously in place at the Sunrise site. Now all well pad controls have been consolidated into a single control platform. In addition to simplifying the architecture, this will help lower hardware and software costs for the site.

The system also enables the use of artificial lift systems, including on/off timers and plunger lift systems, and provides visibility into those systems.

“Operators can track events in the Connected- Production solution to see what stage we’re in of the optimization cycle and make better decisions about what to do next,” Kettner said. “Operators can see, for example, that a timer well is not producing anymore and move to the next step of putting a plunger in the hole.”

The new system also is helping ARC Resources enhance safety by reducing the risk of faults going undetected at the Sunrise site.

“Now if something goes wrong with the processor, or if an I/O [input/output] rack comes undone, the ControlLogix platform can fault to a safe state where it shuts down all the processes,” Kettner said. “It takes all the power off the solenoids and essentially results in an emergency shutdown.”

Another benefit of the ConnectedProduction system is that it can support a flow-measurement card within the control panel. This has allowed Kettner to eliminate the use of a separate flow-measurement computer, which is saving his company tens of thousands of dollars at the site.

“We just plug the card into the rack, and it communicates on the backplane,” Kettner said. “It’s given us huge cost savings.”

Looking ahead, Kettner already has orders in to bring the ConnectedProduction system to at least four more large multiwell pads in the area.

“We’ve seen the value of the Rockwell Automation solution and want to bring it to our other sites where we need assisted lift,” he said. “On new pads we’ll implement this right from day one so it’s there and available when it’s needed. And we can just turn it on.”

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Reduced Tubing Wear with Coupling

The economic landscape of the oil and gas industry has shifted and, as a result, operators in U.S. shale plays are increasingly looking for ways to streamline their practices and boost profitability. Coming to grips with production costs is crucial in the $50/bbl environment, and every component used in production should be scrutinized to assess if changes and improvements can be made to reduce wastage, costs and time lost on the well.

For example, nearly all of the wells operating in U.S. shale fields require artificial lift, and nearly half of those wells experience failure as a result of couplings contacting the inner tube wall, which creates friction that leads to considerable wear and damage. These failures are both hazardous and costly, running into the tens of thousands of dollars per well per year. Across the industry workover costs account for hundreds of millions of dollars per year.

To come up with an efficient, more cost-effective solution for well workovers, Materion Corp. partnered with Hess Corp. to develop and field test stronger, more fatigue-resistant sucker rod couplings made of ToughMet 3 TS95 alloy.

Materion developed a new temper of its ToughMet 3 alloy specifically to address the challenges of coupling on tubing wear. This copper-nickel-tin spinodal alloy was originally engineered by Materion for use in drilling equipment. Offering high strength and low friction, this alloy demonstrates corrosion and corrosion-related stress cracking resistance in seawater, chlorides and sulfides.

With its combination of properties, this alloy resists mechanical wear, thread damage, corrosion and erosion. The couplings are non-galling, so they do not damage production tubing, and they retain their strength even at elevated temperatures.

Bakken-tested

Materion partnered with Hess, one of the largest producers in the Bakken, to qualify and pilot the ToughMet sucker rod couplings in deviated wells with higher than normal failure rates. Hess noted that the couplings more than tripled the mean time between failures associated with couplings made of alternative materials.

Encouraged by the results observed in the field tests, the company installed the couplings in more than 400 of its Bakken wells and now uses the couplings as part of its standard production practice.

Materion is expanding the deployment of its ToughMet couplings with additional operators in several different shale plays. Now about 20 operators are running the couplings in the Bakken and Permian and in the Elk Hills Field in California. To facilitate access to the couplings for operators, Materion is establishing distributors in each of these regions so that the couplings are available from local inventory.

Permian perspective

Discovery Natural Resources LLC is a private oil and gas company that operates more than 1,000 wells in the Permian Basin. To date, the company has used the ToughMet couplings in about 20 wells in the Permian and is seeing positive results.

Discovery owns some wells that were failing every 60 to 90 days, specifically due to rod-on-tubing wear as a result of extreme deviation. The company piloted the ToughMet couplings as a solution and as a result significantly increased the run time on those wells.

Discovery reported that its longest running well with these couplings is more than 385 days without a failure. The company has four additional wells with the couplings installed that are past the 300-day mark. In addition, Discovery has doubled or tripled its run times.

Discovery pulled the rods out of one of the ToughMet test wells after a pump failure and inspected the couplings after three months of the well running. It would typically see significant tubing or coupling wear after this period in the ground but saw that the original stencils from the manufacture were still visible on the coupling (see image above). There was minimal wear observed on the couplings. For Discovery that was an early indication that the couplings reduced rod-on-tubing wear.

Sucker rod pumping in long deviated unconventional wells is especially challenging because of side-loading of rods. Sucker rods can buckle due to forces acting in compression at the bottom of the rodstring on downstroke.

If rod side loads are calculated at more than 100 lb, Discovery considers running ToughMet couplings in that area to increase the run time on that particular well. The company reported that ToughMet is becoming increasingly well-established in its operations. Now that the test phase is completed, the company is using more ToughMet couplings.

By utilizing a sucker rod coupling that actively mitigates coupling-on-tubing wear, operators are helping reduce downtime and improve production efficiencies by eliminating the need for more frequent workovers.

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New drilling technologies could give us so much oil

New oil drilling technologies could increase the world’s petroleum supplies six-fold in the coming years to 10.2 trillion barrels, says a report released today by market research firm Lux Research.

The most common and controversial technique is hydraulic fracturing, or fracking, in which chemical-laced water is injected to break up subterranean rock formations to extract oil and natural gas. But the Lux report details a host of exotic so-called Enhanced Oil Recovery (EOR) technologies—from solar-powered steam injection to microorganisms—that could be used to extend the life of old oil fields and gain access to so-called unconventional petroleum reserves like oil sands.

“In light of current oil prices, the peak oil hysteria and projection of $300 [a barrel] prices of a few years ago seem overblown – if not outright silly,” the report states. “But in a sense, they were accurate forecasts of what would have happened if EOR technologies had not come online and made unconventional oil reserves – which vastly exceed conventional ones – accessible.”

But don’t ditch your electric car just yet. The development of such technologies is predicated on high oil prices – at least $100 a barrel – to offset the costs and induce a conservative industry to invest in and deploy new methods. And many of the technologies are still young.

Moreover, as we’ve seen with fracking, political opposition to technologies that could pollute the environment and use lots of water could derail their use. And as climate change accelerates, opposition to carbon-intensive extraction of fossil fuels and their expanded use is sure to grow.

Still, here are some of the technologies startups and multinationals alike are pursuing:

Thermal intervention injects steam into wells to extract heavy oils or oil sands. The problem is, it takes a lot of energy to generate that steam, so some oil companies are turning to solar energy instead of natural gas or other fossil fuels. Chevron, for instance, has deployed solar fields built by BrightSource Energy and GlassPoint Solar at old oil fields in California to help recover heavy petroleum.

Chemical EOR injects polymers and alkaline compounds into oil fields to help loosen oil from rock formations and push it into production wells. The China National Petroleum Corporation is the leader in this method, which it is betting will be 20% more efficient than just flooding wells with water to bring oil to the surface. But in the US, expect opposition to introducing large volumes of chemical underground anywhere near water supplies. Some other drawbacks: Chemical EOR doesn’t work well in oil reservoirs where temperatures are high and there’s a lot of salt and sulfur.

Microbial EOR uses environmentally benign microorganisms to break down heavier oils and produce methane, which can be pumped into wells to push out lighter oil. The technology dates from the 1950s but only recently has it been put to limited use. An experiment with microbial EOR in Malaysia, for instance, increased oil production by 47% over five months. But oil and gas engineers are not biologists, the report notes, and may be reluctant to embrace the technology.

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New Oil Drilling Technology Will Soon Spark An Explosion Of Oil

Energy stocks have been tearing higher since the election on bets that the Trump administration will relax environmental restrictions and open more federal lands to oil and gas drilling. Crude oil’s staying north of $50 hasn’t hurt, either.

It is up there in part because OPEC threw in the towel and agreed to production limits. Unfortunately for OPEC, those limits don’t apply to US and Canadian shale producers. And the history of OPEC is that they all cheat like crazy, anyway.

There will be no end to oil production

I think it is entirely possible that we will see oil prices climb somewhat further by mid-year, possibly approaching $60, and then pull back as capped US production comes back online. Look at the chart below to see the wide variation among forecasts of major energy analysts working for the big banks.

I also think that this year, we’ll start to see a new pattern: Production could keep rising even as prices fall. Conventional wisdom says that producers stop pumping at some point when it becomes unprofitable, but I think that is about to change.

New technology will lead to greater production and higher profits

If you are an oil producer—or really, any commodity producer—two things can improve your profit margin: higher selling prices for the resource you produce or lower production costs. Some combination of both works as well.

Now, selling prices are mostly outside the producer’s control, though adept hedging can help. Cost reduction is, therefore, the place to concentrate your attention. Back in 2015, I wrote about new drilling techniques and other technology that promised to bring oil and gas production costs significantly lower.

Now, in the last few weeks, people in the business have told me these technologies are moving rapidly toward deployment. They foresee considerably lower drilling and production costs by the end of this year.

I had a confidential briefing recently about some new energy production processes that are coming online in the oil patch. Let me just say that production from an oil well drilled with these new techniques is getting ready to increase substantially.

In some cases, the amount of oil produced per dollar spent on drilling is going to more than double. There are significant chunks of the petroleum-producing parts of the United States where $40 oil will not be a barrier to drilling and new production.

Eventually—in a few years—these techniques will begin to show up in wells around the world, and there will be an explosion of oil. Even as many oilfields dry up, there will be new fields developed from previously unprofitable sources.

This will have massive economic and geopolitical implications

This technology trend means that the current oil price range may well break lower—perhaps this year, but certainly within this decade—without energy companies losing profits.

Not every company will reap the rewards equally, of course; but the industry as a whole is excited. Energy exploration and production is quickly becoming a technology-driven industry with the US as world leader.

If Trump permits construction of more pipelines and natural gas export terminals, we could see North American exports rise considerably in the next few years.

Obviously, over time, a falling energy price will not be good for OPEC or for Russia. Those lower prices will create geopolitical challenges as well as economic ones. I don’t know how it will all shake out. We will likely see some big, energy-driven changes in the world order in the coming decades.

But that is beyond the scope of my crystal ball.

Source: www,forbes.com

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Well’s Production prediction with Microseismic Technology

With efficiency being crucial when every dollar counts, operators in unconventional plays could add microseismic technology to fracture modeling methods to gain insight into permeability advances and better forecast production.

That’s according to Sudhendu Kashikar, vice president of completions evaluation for MicroSeismic Inc.

Understanding drainage volume and improved permeability of stimulated rock are essential to forecasting production, he said. Typically, several models are used to accomplish this, but the approach has its drawbacks.

A single frack model per stage ignores geological variations along the wellbore. Plus, a discrete fracture network (DFN) model is needed to determine how fracturing actually improves the permeability of stimulated rock, Kashikar said.

Microseismic techniques can simplify the workflow and help with production forecasting, Kashikar said during a webcast June 16.

“Technology and procedures were developed to discriminate the microseismic events and fractures described by these events, capturing propped versus unpropped fractures,” Kashikar said while describing Productive-stimulated rock volume (Productive-SRV) technology. “A rock volume capturing the proppant-filled refractures showed much better correlation to the cumulative production than the total stimulated rock volume.”

Productive-SRV technology estimates how much stimulated fracture remains open through proppant placement by using estimated target zone productivity, a DFN, propped fracture estimate and the Fat Fracture drainage estimate, according to MicroSeismic’s website.

Focus is usually on the location of the proppant, but focus should also be on the amount of improved permeability achieved within the SRV or the Productive-SRV, he said.

Understanding and measuring such improvements will lead to the next step in reservoir stimulation and production forecasting, he said.

Using microseismic data has proven beneficial in establishing a deterministic DFN, which shows fractures detected through seismic.

“For every microseismic event we describe a fracture plane. The size is guided by the magnitude, and the orientation comes from the focal mechanism,” he said. “This is much easier to do with surface microseismic.”

The model is calibrated to actual fluid volumes pumped for a well. A mass balance approach is used to fill the fractures with proppant starting from the wellbore moving outward until the proppant is consumed for that stage, Kashikar explained. Once the fracture network and the propped network have been established, a geocellular grid can be superimposed to obtain the SRV and productive SRV to capture the proppant-filled rock volume, he said.

“One advantage of this workflow is the ability to capture fracture intensity—the number of fractures, the orientation of these fractures—to quantify the permeability enhancement achieved,” Kashikar added.

Key steps for the production forecasting workflow are describing three reservoir volumes—the productive SRV (the propped fractures), total SRV (includes propped and unpropped fractures) and the permeability scalar for individual cells within each region to determine how permeability improved for neighboring cells.

This workflow, he said, captures not only the size and shape of the drainage volume but also permeability within the drainage volume.

The process is a big step forward, he said, in understanding and determining the effectiveness of hydraulic fracturing.

“Rather than relying on a single representative fracture model, we can fully and accurately capture the variable fracture geometry and fracture intensity for the entire length of the wellbore, providing a much better production forecast,” Kashikar said. “We can now use the productive stimulated rock volume and the stimulated rock volume with permeability scalars to directly and explicitly describe the reservoir volume in the reservoir simulator.”

Source: www.epmag.com

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Drilling Well Pacing

The pacing process and can be used to improve the flow of natural gas or crude oil into a well hole. This can be accomplished through a variety of intervention techniques, many of which are designed to increase permeability outside the hole. The two ways of increasing permeability are to clean the formation or increase drilling and fracture in the tank. Another technique that can be effectively used in pacing is good gas lifting, which can be useful to start a well or extract heavy compounds that are actually killed. All of these various stimulation techniques and can improve the output of a petroleum or gas reservoir, increasing the incoming hydrocarbon stream and hole.

When the oil or gas is in an easily removable form, it is usually found in a reservoir. These tanks are porous or fractured rock formations that the oil or gas is contained inside. To extract hydrocarbons, a well hole can be drilled in the formation. The oil or gas will then tend to penetrate through porous or fractured rock, into the hole, and up to the surface. A common form of intervention is the process of stimulation, which is designed to speed up the rate at which hydrocarbons move through the formation.

One of the common methods of stimulation is to increase the permeability of the oil or gas tank. The permeability of the formation is often reduced due to the drilling process, and chemicals can enter and block porous rock. Drilling can also force rock fragments into cracks and cracks, further blocking the reservoir. To clean the formation, the chemicals are often pumped along the hole to melt the blocks. Formic acid is often used in a process known as acidification, which can dissolve blocks and allow hydrocarbons to flow.

Another way that the permeability of a formation can be increased is to create additional crevices or fractures in the rock. Hollow loads are a type of shaft stimulation that can increase the number of fractures near the well hole. Another method is hydraulic fracturing, which can result in pumping high pressure fluids along the well hole. Other explosive materials can also be used to release high pressure propellants in the formation, creating additional cracks and fractures inside the tank.

Gas lifting is a pacing technique that can be used to get the flow started or to repair a well that has been killed. This technique generally involves the circulation of nitrogen or other substances with spiral tubes. Sometimes, this is only done to get the flow started, after which the nitrogen circulation has ceased. In other cases, the same technique can be used to lift heavy substances, such as chemical scale reducers or water, which have been established in the hole and blocked the flow of hydrocarbons.

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Countries with Large Crude Oil Reserves

Identifying countries with large crude oil reserves is important, but it's just a starting point, as you start investing in raw materials. To determine which countries are making good use of these reserves, one should look at another important metric: actual production. Having big reserves does not make sense if a country is not touching such reserves for oil production.

Rank country Daily production (millions of barrels)

1 Saudi Arabia 10.8

2 Russia 9.8

3 United States 8.5

4 Iran 4.2

5 Porcelain 4.0

6 Canada 3.4

7 Mexico 3.2

8 United Arab Emirates 3.0

9 Kuwait 2.8

10 Venezuela 2.6

Source: United States Department of Energy

A number of factors influence how many crude countries will be able to pump off day-to-day, including geopolitical stability and the application of technically advanced raw recovery techniques. It also recalls that daily production may change over the course of the year due to interruptions resulting from geopolitical events such as embargoes, sanctions and sabotage that end the daily production or other external factors such as the weather.

For example, consider Hurricane Katrina and its devastating effect on US oil supplies in the summer of 2005, as well as the Gulf BP oil spill in 2010.

You need to keep an eye close to the global daily supply because any problem in the production supply chain can have a big impact on the current crude price. Because there is a narrow supply and demand equation, any feed interruption that can send star prices to crude.

Merchant merchants follow the crude oil production numbers in the near future. Crude Benchmark Contracts, such as the West Texas Intermediate (WTI), traded on the Chicago Mercantile Exchange (CME), and North Sea Brent, traded on the Intercontinental Exchange (ICE) in London, are affected by supply numbers. As a result, the market looks carefully at every geopolitical event or natural disaster that can reduce production.

If you are an active oil merchant with a future account, following these daily production numbers - which are available through the Energy Information Administration (EIA) site - is paramount. Futures markets are particularly sensitive to crude oil production per day, and any unprocessed event may have a sudden impact on oil futures contracts.

If you are a long-term investor in the markets, monitoring this issue is also important because production data may have an impact on overall stock market performance as well. For example, if rebels seize a pipeline in Nigeria and 300,000 barrels of Nigerian crude oil are withdrawn from the market, this will result in higher crude prices, which will have an impact on the US stock market (which typically fall).

Thus, your equity investments in the portfolio may be at risk due to daily production of crude oil. Therefore, monitoring this statistic regularly is important for both short-term and long-term investors.

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Abandoned Well

An abandoned good is a well that has been perforated and then abandoned, for any number of reasons. Abandoned wells pose a health and safety risk around the world and are a cause of concern especially in suburban communities and formerly converting to the use of water wells for municipal water supply. Many regions have specific laws on abandoned wells and how they should be treated, with the aim of reducing the risk of pollution and damage to empty wells.

The risk of injury is clear: someone might fall into an abandoned pit and not be able to get out. The fall could injure or kill someone, and unless the help comes quickly, the victim of the fall could die in the pit. Especially if an abandoned person is in a remote area, it may take days to realize that someone has fallen into the pit. Abandoned water wells also pose a threat to wildlife for the same reason.

In the case of an abandoned well, the well can serve as a pollutant storage site and release these pollutants into the natural environment. These pollutants may include materials leaked from septic tanks, which can pose a threat to human health if groundwater enters an abandoned well. Abandoned oil and gas wells can also serve as a source of pollution, and releases unexpected or rockets of material could pose a risk to safety and health.

If a well is temporarily put out of use, it may be simply limited. Capping involves covering the good so that content is not accessible. Ideally, the cap must be clearly labeled and regularly checked to detect any signs of intrusion or damage that could indicate that the cap is about to fail. Capping is also not intended to be a permanent measure, and people can be penalized for not having to deal with abandoned and adequately if they leave a well covered for too long.

If a well is really abandoned and will not be reused, it must be sealed. The sealing lens is to restore the conditions that were present in the soil before the well was perforated. The seal is run by a well-drilled drill, and typically requires permission from any local authority to handle excavation and sealing of wells. Sealing should be done with care to avoid injuries and to properly seal the good so that the problems with abandoned good will not emerge in the future.

• Pumpjacks are often used in wells that produce little oil. Once it is more expensive to remove the oil than it earns, a well is often abandoned.
• An abandoned well can serve as a storage site for pollutants, which includes laundered septic tanks.

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Fracking, thousands of spills and accidents in US oil and gas wells

Spills of polluted fluids and chemicals from 16% of unconventional hydrocarbon wells

According to the study of "Unconventional Oil and Gas Spills: Risks, Mitigation Priorities, and State Reporting Requirements" published by Environmental Science & Technology by a team of US researchers led by Laureen Patterson of the Harvard Law School's Environmental Policy Initiative, the situation of the pollution generated by the USA fracking wells is serious: every year, from 2 to 16% of oil and gas wells exploited by the fracking technique in Colorado, New Mexico, North Dakota and Pennsylvania there have been spills of hydrocarbons, water filled with chemicals, fluids of hydraulic fracturing and other substances. The largest spillage tested by the study resulted in the leak of 100,000 liters of polluting liquids.

The study dealt with unconventional oil and gas spills in 31,481 wells operated by fracking technique in the 4 US states between 2005 and 2014, identifying 6,648 spills over the past 10 years. In all states, the first three years of a well's life, during drilling and hydraulic fracturing, have had the highest production volumes but also the highest risk of spillage. A significant part of the spills (from 26% in Colorado to 53% in North Dakota) occur in wells that have suffered more than one spill, "Which suggests that wells in which spillages have already occurred deserve more attention," they say researchers.

Figures that worsen many of the previous study, "Environmental Impact Assessment of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources" of the Environmental Protection Agency (EPA) on fracking in 8 US states between 2006 and 2012, which had concluded that there were 457 spills.

Patterson, interviewed by BBC News, explains why this strong difference: "The EPA has only looked at spills during the same process of hydraulic fracturing, which take place only in a period ranging from a few days to a few weeks. We have investigated spills in unconventional wells from the time of perforation throughout the production, which could last decades. "

In North Dakota, there were 4.453 accidents 

recorded

 , much more than in Pennsylvania, Colorado and New Mexico, and this can be explained with the different types of reporting. In North Dakota there must be reported any spill over 42 gallons, while in Colorado and New Mexico starts from 210 gallons.

Most of the spills occur during the first three years of wells activity and about 50% of spills occur from the pipelines for the transport of polluted fluids.

"The causes are quite different," says Patterson. "Equipment failures are the major factor, loading and unloading of trucks with material is a far more common human error than in other places."

. Researchers are convinced that "making state data on spills more consistent and accessible could provide stakeholders with important information on where to target efforts to identify and prevent 

future

 losses. However, reporting obligations differ between states, which requires considerable effort to make the data usable in order to be able to analyze them. "

Another author of the study, Kate Konschnik, also of the Harvard Law School, concludes: "Analysis like this is really important to defining and reducing the risks for water supply and human health. Writing state regulations for reporting these factors in mind is crucial to ensuring that correct data is available in the industry, the states and the research community, and in an accessible form. "

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What is Blow Out Preventer - BOP

The blowout preventer or BOP is a particular device used during the drilling of a hydrocarbon well that has the task of securing the well during the drilling phase, in case the underground fluids accidentally migrate to the outside of the well , during drilling.

The well can be assimilated to a circular section duct, therefore substantially to a long pipe . The hydrocarbon is contained in the porous ground pores, subjected to the formation pressure and maintained in the rock by the counter pressure exerted on the hole walls of the drilling mud .

If for any reason, these fluids, coming from the well, toward the surface, would reach the perforation plant , which is on the surface of the well mouth. In this way the plant would be seriously threatened by the risk of fires and explosions , just because the gas is easily flammable . Among other things, such gases, rising upwards, expand because it decreases the hydrostatic pressure to which they are subjected. This would mean that the whole plant would be wrapped in flammable gas, ready to light up to the minimum spark or hot surface contact. Even if the gases do not get burned, they would cause respiratory or asphyxiating problems as wellpersonal poisoning .

The BOP is therefore used to close the shaft in emergency situations, ie blocking its section in case of blowout , that is, the shaft eruption (so is called the hydrocarbon spill from it).

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Oil Extraction Process

After completion of a drilling step, a series of geoelectric surveys ( logs ) are generally carried out , dropping into the well of the probes. Once this phase has been completed, the well can be intubated by dropping various sections of steel tubes as a hole coating. Coating tubes are cemented to the rock to prevent hydrocarbon leaks or other fluids in the tubular-rock gap.

Finally, the well is completed internally by installing a series of small diameter tubes (7 to 12 cm, tubing ) that have the function of driving oil outside. The well's mouth is equipped with a safety valve system (oil spout called "Christmas Tree") that allows controlled oil delivery in temporary storage tanks or its direct injection into a pipeline .

If the pressure of the oil is not enough to make it trace inside the pipes to the surface or if you want to speed up the mining activity, you can mount the pumps on both the surface and the bottom well. 

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Drilling Rig

A drilling rig is a machine that creates holes in the earth sub-surface. Drilling rigs can be massive structures housing equipment used to drill water wells, oil wells, or natural gas extraction wells, or they can be small enough to be moved manually by one person and are called augers. Drilling rigs can sample sub-surface mineral deposits, test rock, soil and groundwater physical properties, and also can be used to install sub-surface fabrications, such as underground utilities, instrumentation, tunnels or wells. Drilling rigs can be mobile equipment mounted on trucks, tracks or trailers, or more permanent land or marine-based structures (such as oil platforms, commonly called 'offshore oil rigs' even if they don't contain a drilling rig). The term "rig" therefore generally refers to the complex of equipment that is used to penetrate the surface of the Earth's crust.

Small to medium-sized drilling rigs are mobile, such as those used in mineral exploration drilling, blast-hole, water wells and environmental investigations. Larger rigs are capable of drilling through thousands of metres of the Earth's crust, using large "mud pumps" to circulate drilling mud (slurry) through the drill bit and up the casing annulus, for cooling and removing the "cuttings" while a well is drilled. Hoists in the rig can lift hundreds of tons of pipe. Other equipment can force acid or sand into reservoirs to facilitate extraction of the oil or natural gas; and in remote locations there can be permanent living accommodation and catering for crews (which may be more than a hundred). Marine rigs may operate thousands of miles distant from the supply base with infrequent crew rotation or cycle.

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Maritime transport on oil tankers

The shipping of oil on board tankers (tankers and super tankers carrying up to 400,000 tons of crude oil), represents more than half of world maritime trade. One can imagine the consequences of oil shortage on commercial! (On others for that matter ...).

Initially the oil was transported aboard wooden casks (barrels). The barrel has remained the unit of exchange used. It is 159 L. Now tankers are designed as huge reservoirs, sometimes divided into several compartments to store oil of different characteristics (including density). So we can better manage the weight distribution on the ship.

Over the past 30 years, many maritime disasters involving super-tankers have been held. They have caused ecological and economic disasters along the coast affected by oil spills. Most of the cleanup costs and compensation were supported by local e local governments. The Coastal Cleanup is in turn often provided by volunteers.

Since then, new oil transport ships are equipped with double hulls, which are supposed to reduce disaster risks. But they do not prevent the practice of degassing, responsible for oil spill at sea ... The single-hulled tankers still represent the vast majority of the park. 

The gigantic size of the super-tankers creates monstrous consumption of fuel, but which are reasonable compared to their carrying capacity. Currently, more than 600 tankers with a tonnage greater than 200,000 tonnes in circulation.

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Cracking and reforming

Cracking is to break the long hydrocarbon molecules into smaller molecules. This can be done by thermal process under high pressure, or catalytic (under high temperatures and in the presence of a compound that facilitates the chemical reaction). When hydrogen is involved, it is called hydrocracking, is when water is called steam cracking. 

The reforming to convert naphtha to produce gasoline or premium. 

There are other processes refining as isomerization, alkylation, etc. ... We can thus influence the characteristics of the products obtained (octane, color, odor, volatility ...).

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Distillation

Crude oil is first heated to 370 ° C. It then partially vaporizes and is carried out in a fractionating column (a kind of distillation tower). 

At the top of the column is recovered refinery gas used as fuel on site. It also recovers other petroleum gas such as butane and propane, gasoline and naphtha. The latter is the base compound of the petrochemical industry. Then recovered kerosene (used iFn aviation, the jet engines), diesel and heating oil. Further down the column is recovered residues, which are re-distilled under vacuum to provide heavy fuel oil, lubricants and bitumen. 

In order to obtain specific grades of gasoline (high octane) and reduce the content sulfur diesel fuels, we must also deal with products of distillation.

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Drilling for oil

After the drilling of one exploration well, designed to confirm the presence of oil and other wells are drilled to delineate the deposit. Most wells are drilled using a drill bit, a cutting tool on the end of a set of drill pipe supported by a metal tower called derrick. The drill bit is rotated. The drilling speed varies greatly depending on the nature of the rocks traversed. Of the "drilling mud" (a mixture of clay with water and chemicals) is continuously injected inside the stems. It goes back into the space between the rods and the walls of the well. The mud serves to cool the drill bit and remove the cuttings. Back on the surface, the slurry is filtered and reinjected into the well. Analysis of the debris can qualify the rocks traversed. 

Advances in drilling techniques now allow the completion of drilling small diameter boreholes deviated (obliques), horizontal multidrains, etc ... This progress has allowed the exploitation of deposits that were previously unprofitable, for technical reasons and / or economic. 

For offshore deposits (offshore), is generally used for pumping platform independent. Special ships can be used to exploit deposits of lower capacity.

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Autonomy of oil reserves

Considering that between 850 and 950 have been consumed Gbl today.

Often given an estimate of oil reserves equivalent to 40 to 60 years of world consumption today is to say slightly less in reality if we take into account the steady rise in consumption, mainly due to the emergence of newly industrialized countries such as China and India. However, the thin oil should lead to an increase in prices, which in turn should limit consumption to the profits of alternative energy sources, fossil fuels (coal, etc.), or renewable. All things considered, it is reasonable to think that we have about 50 years of oil. Remains to be seen at what price ...

It took a century for humanity to consume half of the oil, it will take more than a half to fully deplete the reserves.

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State of the World's Oil Reserves

A simplified figure and relatively speaking: a cube of 7 kilometers from the side, half empty (or half full, it depends), with a leak rate equivalent to the Rhone is the current state of reserves and world oil consumption.

Proven reserves are generally estimated at between 140 and 160 Gt, or 1,050 to 1,200 Gbl. But taking into account technological advances and a recovery rate above 30%, the reserves could reach 266 Gt (or 1'996 GBL). The truth is that the reserves are not well known, and that in addition to proven reserves, it is quite inappropriate to make hypothetical assumptions about the probable reserves and ultimate.

Fairly coarse (and varies according to findings nouvaux oilfields), proven reserves are geographically distributed as follows:

• 55-60% in the Middle East;
• 15-18% in North America;
• 7-8% in Central and South America;
• 6-7% in Eastern Europe and Former Soviet Union;
• 6-8% in Africa;
• 3-5% in Asia and Oceania;
• 1-2% (!) In Western Europe;

I'll let you calculate how many tons or barrels this is by geographic area.

The countries of OPEC account for approximately 75-80% of total world proven reserves. Several sources say, however, that the state reserves of many countries been an overestimate: these optimistic data are primarily used to sit supremacy and economic influence of the major producing countries.

The rise in oil prices led to interest in deposits unconventional oil , such as oil sands, whose operation is known as energy-intensive, highly polluting, and catastrophic for the environment (despite some methods that allow to avoid the creation of open pits).

Global warming also affects some plan to use: the melting of arctic ice led some companies (such as Arctic Oil & Gas Corp) interest in the exploitation of hitherto inaccessible deposits.

Finally, the exploitation of new (types of) deposits appears to be the preferred track to generate more wealth to the detriment of the fight against global warming and more generally the protection of the environment. Or how to cut ever more ardently the branch on which we sit ...

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