The Hydraulic Fracking Process Explained Step by Step: How Does It Work?
Gold, oil, iron, coal are just some of the Earth’s resources that make us feel lucky for living on a planet filled with underground riches. However, many of them have made it on Earth’s endangered list and oil causes most concern. Is hydraulic fracking the answer to that?
Also called liquid gold, oil is the fuel that keeps a billion cars running, as well as millions of home heating systems, and thousands of power plants. For about half a century, economists and geologists have all been warning us about the end of cheap oil. On the other hand, environmentalists have been concerned about our overdependence on fossil fuels (coal, oil, and gas). So what is there to be done?
Fossil Fuel Dependency
What will the world’s planet do when the oil deposits are depleted? In an ideal scenario, we will have already swapped our gas guzzlers for electric cars and the dirty coal power plants will be rendered useless by green solar and wind energy. But that transition could take decades, so what is the solution in the meantime?
What if there was a way to squeeze a little bit more fuel from our planet’s rocks to keep us going? That’s what fracking (scientifically called “hydraulic fracturing”) proposes. Gas and oil companies believe that hydraulic fracking could be the economic lifeline that keeps them in profit for a few more decades.
On the other hand, environmentalists consider it an environmental catastrophe. Fracking could be the last straw that breaks the camel back, a.k.a. tips the planet over the edge into disastrous climate change. So can we really afford fracking for oil? Or can we afford not to?
What is Hydraulic Fracking?
In simpler terms, fracking is a process that involves blasting high-pressure jets of water into underground oil and gas deposits so we can flush out more of Earth’s resources located in hard to reach places.
When you think about it a little bit, hydraulic fracturing is actually a self-explanatory term. In engineering and science, “hydraulics” refers to using pressurized water to power all sorts of machines. If you shoot water down an oil or gas well, the sheer pressure will fracture (crack apart) the rocks inside, allowing the trapped gas and oil to flow to the surface and be collected.
Some of these tricky deposits are buried deep down so we have trouble drilling down to them. That’s why we use fracking in combination with another oil exploration technique – horizontal drilling (a.k.a. directional drilling).
In a traditional oil well, the drill string (the spinning pipe that carries the drill underground) goes straight down. With horizontal drilling, the entire string can bend through sharp angles so oil and gas sites located to the side can also be accessed. This allows a single drilling rig on the surface to be used for a number of different horizontal wells in various directions.
Using this combination of hydraulic fracking and horizontal drilling has made it possible to exploit three hard-to-reach types of geological deposits: coalbed methane (CBM) deposits (the methane gas that occurs naturally in coalfields); shale gas (natural gas trapped in shale formations); and tight sands (limestone and sandstone rocks in which natural gas is tightly locked).
Hydraulic fracturing is not a complicated process, once you’ve been walked through each of the components of a drilling rig. Fracking begins with a well bored several thousand meters vertically through groundwater rocks (aquifers) and then horizontally into a gas or oil deposit.
After the drilling, the resulting hole is cased with a long steel pipe sunk down its entire length. Cement is used to keep it in place as a giant “drinking straw.” This pipe allows us to extract the gas and oil in that deposit.
A specialized perforation gun is dropped down through the pipe. At the same time, several small explosive charges create holes at various points of the pipe for the fracking fluid to be pumped in at high pressure. Trucks on the surface are responsible with delivering the fracking fluid underground. The result of this action is many small cracks in the rocks, which allow the trapped gas or oil to escape.
Fracking Fluid & Flowback
The name “hydraulic fracturing” suggests the involvement of water in the drilling process, but fracking fluid actually contains more equally important ingredients:
- Water – This is the most important element. Up to millions of gallons are sunk in each well, as the water is responsible with the actual fracturing.
- Proppant – A collective term used for small ceramic balls and gritty sand used to lodge in the fractured rock. Basically, proppant is supposed to hold the cracks open so gas or oil can flow through. The water and proppant together make up approximately 99 percent of the fracking fluid.
- Fracking Chemicals – The last percent is made up of gelling and lubricating agents and antimicrobial chemicals. Not only do they help to carry the proppant, but also improve the quality and quantity of oil or gas collected from one well.
After the rock has been fractured, the pumping stops. As a result, the pressure is released, so the gas or oil that’s been previously trapped underground now flows freely to the surface with some of the water and chemicals in the fracking fluid. Due to the fact that other deposits are also flushed up, all of the ingredients surfacing are technically called flowback.
Hydraulic fracking also releases what’s called produced water. This is naturally occurring water that’s trapped in something similar to a shale formation. Produced water (or released water) is also a carrier for naturally radioactive materials, trapped minerals, and so on.
Economy vs. Environment
Ask most environmentalists and they’ll tell you fracking is a dangerous distraction from the urgent need to reduce our “addiction” to fossil fuels. But the issue is rarely so black and white. All of us rely on fossil fuels for transportation and home heating; they provide about 80 percent of our total energy.
And when all is said and done, everything has an energy impact. However hard we might try, it’s next to impossible to not consume energy every day of our lives. We live in a world that uses fossil fuels for everything it does. In short, we have very compelling economic reasons to try and boost supplies of gas and oil.