Hydraulic Fracturing 101
Hydraulic Fracturing Process
Hydraulic fracturing has been a topic of interest lately and yet it is still not widely understood. Natural gas plays a large part in the future of the United States’ clean energy, and hydraulic fracturing has become a great option to obtain it. Hydraulic fracturing is a complex process in which natural gas or oil is obtained.Wells are commonly drilled hundreds or thousands of feet into the ground, and while it may reach the larger quantities of gas or oil, there are small pockets that are not being reached.The process of hydraulic fracturing allows the smaller pockets to be reached and used, which can actually increase the yield by hundreds of percentages. It also allows older fields of natural gas and oil to be used even after regular drilling no longer yields any product.
Fractures are created by pumping large amounts of liquid at high pressures down into wells. The liquid usually consists of water, proppant, and chemical additives which helps to hold open the newly created fractures. Water and sand make up about 98 to 99 percent of the fluid that is injected. After this part of the process is completed, fluid will surface from the well. This is called “flowback,” it may contain a variety of materials such as brines, metals, radionuclides, and hydrocarbons. This liquid is stored on site and usually treated and recycled. Natural gas and oil are then extracted from the fractures.
Sources for Hydraulic Fracturing
There are few different sources of natural gas and oil that can be obtained through hydraulic fracturing such as in shale rock formations, coalbed methane, and tight sands. Shale rock formations are the most common source for hydraulic fracturing. These formations occur throughout the United States in many different locations, and in some cases in places where natural gas or oil had not been available for extraction.
Coalbed methane (CBM) was first produced in coal mines as a safety measure to decrease the chances of dangerous explosions due to methane gas. Today it is produced and used as a source of energy. Some deeper coal formations may require hydraulic fracturing in order to obtain this natural gas.
Tight sands are gas-bearing, fine-grained sandstones or carbonates with a low permeability. Unless natural fractures are already present, hydraulic fracturing is almost always needed to release the natural gas.
Before hydraulic fracturing many of these sources were unreachable and unable to produce natural gas or oil. It will allow us to reach new sources as well as allow us to keep using older wells. Experts believe that 60 to 80 percent of the current wells drilled in the United States will require hydraulic fracturing to keep functioning within the next ten years. Hydraulic fracturing is a great way to obtain and produce natural gas and oil that could not have been reached before.